Bump version to 3.8.4

isTooDivergent will be true or false if a definitive decision has been made, or missing from the response if not yet known. Therefore it should be safe to treat `"isTooDivergent": false` as a peer that is on the same chain.

TestNets.md

@@ -52,14 +52,13 @@
 
 ## Single-node testnet
 
-A single-node testnet is possible with code modifications, for basic testing, or to more easily start a new testnet.
-To do so, follow these steps:
-- Comment out the `if (mintedLastBlock) { }` conditional in BlockMinter.java
-- Comment out the `minBlockchainPeers` validation in Settings.validate()
-- Set `minBlockchainPeers` to 0 in settings.json
-- Set `Synchronizer.RECOVERY_MODE_TIMEOUT` to `0`
-- All other steps should remain the same. Only a single reward share key is needed.
-- Remember to put these values back after introducing other nodes
+A single-node testnet is possible with an additional settings, or to more easily start a new testnet.
+Just add this setting:
+```
+"singleNodeTestnet": true
+```
+This will automatically allow multiple consecutive blocks to be minted, as well as setting minBlockchainPeers to 0.
+Remember to put these values back after introducing other nodes
 
 ## Fixed network
 
@@ -93,3 +92,32 @@ Your options are:
 - `qort` tool, but prepend with one-time shell variable: `BASE_URL=some-node-hostname-or-ip:port qort ......`
 - `peer-heights`, but use `-t` option, or `BASE_URL` shell variable as above
 
+## Example settings-test.json
+```
+{
+  "isTestNet": true,
+  "bitcoinNet": "TEST3",
+  "repositoryPath": "db-testnet",
+  "blockchainConfig": "testchain.json",
+  "minBlockchainPeers": 1,
+  "apiDocumentationEnabled": true,
+  "apiRestricted": false,
+  "bootstrap": false,
+  "maxPeerConnectionTime": 999999999,
+  "localAuthBypassEnabled": true,
+  "singleNodeTestnet": true,
+  "recoveryModeTimeout": 0
+}
+```
+
+## Quick start
+Here are some steps to quickly get a single node testnet up and running with a generic minting account:
+1. Start with template `settings-test.json`, and create a `testchain.json` based on mainnet's blockchain.json (or obtain one from Qortal developers). These should be in the same directory as the jar.
+2. Make sure feature triggers and other timestamp/height activations are correctly set. Generally these would be `0` so that they are enabled from the start.
+3. Set a recent genesis `timestamp` in testchain.json, and add this reward share entry:
+`{ "type": "REWARD_SHARE", "minterPublicKey": "DwcUnhxjamqppgfXCLgbYRx8H9XFPUc2qYRy3CEvQWEw", "recipient": "QbTDMss7NtRxxQaSqBZtSLSNdSYgvGaqFf", "rewardSharePublicKey": "CRvQXxFfUMfr4q3o1PcUZPA4aPCiubBsXkk47GzRo754", "sharePercent": 0 },`
+4. Start the node, passing in settings-test.json, e.g: `java -jar qortal.jar settings-test.json`
+5. Once started, add the corresponding minting key to the node:
+`curl -X POST "http://localhost:62391/admin/mintingaccounts" -d "F48mYJycFgRdqtc58kiovwbcJgVukjzRE4qRRtRsK9ix"`
+6. Alternatively you can use your own minting account instead of the generic one above.
+7. After a short while, blocks should be minted from the genesis timestamp until the current time.

WindowsInstaller/Qortal.aip

@@ -17,10 +17,10 @@
     <ROW Property="Manufacturer" Value="Qortal"/>
     <ROW Property="MsiLogging" MultiBuildValue="DefaultBuild:vp"/>
     <ROW Property="NTP_GOOD" Value="false"/>
-    <ROW Property="ProductCode" Value="1033:{E5597539-098E-4BA6-99DF-4D22018BC0D3} 1049:{2B5E55A2-142A-4BED-B3B9-5657162282B7} 2052:{6F19171F-4743-4127-B191-AAFA3FA885D2} 2057:{A1B3108D-EC5D-47A1-AEE4-DBD956E682FB} " Type="16"/>
+    <ROW Property="ProductCode" Value="1033:{6C93A96C-E3AF-42FD-BE11-7EC3734905C6} 1049:{754F5347-82E5-4251-AED0-F4141CDD11F5} 2052:{413BD7B3-A3F8-47D0-BCA4-5C7694A40936} 2057:{71450AC8-1E6F-4469-852D-0591FA693680} " Type="16"/>
     <ROW Property="ProductLanguage" Value="2057"/>
     <ROW Property="ProductName" Value="Qortal"/>
-    <ROW Property="ProductVersion" Value="3.4.3" Type="32"/>
+    <ROW Property="ProductVersion" Value="3.8.3" Type="32"/>
     <ROW Property="RECONFIG_NTP" Value="true"/>
     <ROW Property="REMOVE_BLOCKCHAIN" Value="YES" Type="4"/>
     <ROW Property="REPAIR_BLOCKCHAIN" Value="YES" Type="4"/>
@@ -212,7 +212,7 @@
     <ROW Component="ADDITIONAL_LICENSE_INFO_71" ComponentId="{12A3ADBE-BB7A-496C-8869-410681E6232F}" Directory_="jdk.zipfs_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_71" Type="0"/>
     <ROW Component="ADDITIONAL_LICENSE_INFO_8" ComponentId="{D53AD95E-CF96-4999-80FC-5812277A7456}" Directory_="java.naming_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_8" Type="0"/>
     <ROW Component="ADDITIONAL_LICENSE_INFO_9" ComponentId="{6B7EA9B0-5D17-47A8-B78C-FACE86D15E01}" Directory_="java.net.http_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_9" Type="0"/>
-    <ROW Component="AI_CustomARPName" ComponentId="{F17029E8-CCC4-456D-B4AC-1854C81C46B6}" Directory_="APPDIR" Attributes="260" KeyPath="DisplayName" Options="1"/>
+    <ROW Component="AI_CustomARPName" ComponentId="{EC7B4AD9-F2D9-48C4-A586-C4697D9C380C}" Directory_="APPDIR" Attributes="260" KeyPath="DisplayName" Options="1"/>
     <ROW Component="AI_ExePath" ComponentId="{3644948D-AE0B-41BB-9FAF-A79E70490A08}" Directory_="APPDIR" Attributes="260" KeyPath="AI_ExePath"/>
     <ROW Component="APPDIR" ComponentId="{680DFDDE-3FB4-47A5-8FF5-934F576C6F91}" Directory_="APPDIR" Attributes="0"/>
     <ROW Component="AccessBridgeCallbacks.h" ComponentId="{288055D1-1062-47A3-AA44-5601B4E38AED}" Directory_="bridge_Dir" Attributes="0" KeyPath="AccessBridgeCallbacks.h" Type="0"/>
@@ -1173,7 +1173,7 @@
     <ROW Action="AI_STORE_LOCATION" Type="51" Source="ARPINSTALLLOCATION" Target="[APPDIR]"/>
     <ROW Action="AI_SetPermissions" Type="11265" Source="userAccounts.dll" Target="OnSetPermissions" WithoutSeq="true"/>
     <ROW Action="CustomizeLog4j2PropertiesScript" Type="3109" Target="Script Text" TargetUnformatted="var actionData = Session.Property(&quot;CustomActionData&quot;);&#13;&#10;var actionDataArray = actionData.split(&quot;|&quot;);&#13;&#10;var appDir = actionDataArray[0];&#13;&#10;var dataFolder = actionDataArray[1] + actionDataArray[2] + &quot;\\&quot;;&#13;&#10;&#13;&#10;var ForReading = 1, ForWriting = 2, ForAppending = 8;&#13;&#10;var fso = new ActiveXObject(&quot;Scripting.FileSystemObject&quot;);&#13;&#10;&#13;&#10;// Make copy&#13;&#10;fso.CopyFile(appDir + &quot;log4j2.properties&quot;, appDir + &quot;log4j2-orig.properties&quot;, true); // overwrite&#13;&#10;&#13;&#10;// Rewrite %AppDir%\log4j2.properties to update logfile storage path&#13;&#10;var fin = fso.OpenTextFile(appDir + &quot;log4j2-orig.properties&quot;, ForReading, false); // no create&#13;&#10;var fout = fso.OpenTextFile(appDir + &quot;log4j2.properties&quot;, ForWriting, true); // can create&#13;&#10;&#13;&#10;// Copy lines with rewriting where necessary&#13;&#10;while( !fin.AtEndOfStream ) {&#13;&#10;&#9;var line = fin.ReadLine();&#13;&#10;&#13;&#10;&#9;var start = line.indexOf(&quot;property.dirname&quot;);&#13;&#10;&#9;if (start &gt; 0) {&#13;&#10;&#9;&#9;// line: # property.dirname = ...appdata...&#13;&#10;&#9;&#9;// uncomment/replace this line for Windows&#13;&#10;&#9;&#9;fout.WriteLine( &quot;property.dirname = &quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) );&#13;&#10;&#9;} else {&#13;&#10;&#9;&#9;// not found - output verbatim&#13;&#10;&#9;&#9;fout.WriteLine( line );&#13;&#10;&#9;}&#13;&#10;}&#13;&#10;&#13;&#10;fin.Close();&#13;&#10;fout.Close();&#13;&#10;" AdditionalSeq="AI_DATA_SETTER_4"/>
-    <ROW Action="CustomizeSettingsJsonScript" Type="3109" Target="Script Text" TargetUnformatted="var actionData = Session.Property(&quot;CustomActionData&quot;);&#13;&#10;var actionDataArray = actionData.split(&quot;|&quot;);&#13;&#10;var appDir = actionDataArray[0];&#13;&#10;var dataFolder = actionDataArray[1] + actionDataArray[2] + &quot;\\&quot;;&#13;&#10;&#13;&#10;var ForReading = 1, ForWriting = 2, ForAppending = 8;&#13;&#10;var fso = new ActiveXObject(&quot;Scripting.FileSystemObject&quot;);&#13;&#10;&#13;&#10;// Create basic %APPDIR%\settings.json with path to real settings.json in dataFolder&#13;&#10;var fts = fso.OpenTextFile(appDir + &quot;settings.json&quot;, ForWriting, true);&#13;&#10;&#13;&#10;fts.WriteLine( &quot;{&quot; );&#13;&#10;// We need to escape Windows path backslashes to keep JSON valid&#13;&#10;fts.WriteLine( &quot;  \&quot;userPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;\&quot;&quot; );&#13;&#10;fts.WriteLine( &quot;}&quot; );&#13;&#10;&#13;&#10;fts.Close();&#13;&#10;&#13;&#10;// Make copy&#13;&#10;fso.CopyFile(dataFolder + &quot;settings.json&quot;, dataFolder + &quot;settings-orig.json&quot;, true); // overwrite&#13;&#10;&#13;&#10;// Rewrite settings.json to update repository path&#13;&#10;var fin = fso.OpenTextFile(dataFolder + &quot;settings-orig.json&quot;, ForReading, false);&#13;&#10;var fout = fso.OpenTextFile(dataFolder + &quot;settings.json&quot;, ForWriting, true);&#13;&#10;&#13;&#10;// First line should contain opening brace&#13;&#10;fout.WriteLine( fin.ReadLine() );&#13;&#10;&#13;&#10;// Append our entries&#13;&#10;fout.WriteLine( &quot;  \&quot;repositoryPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;db\&quot;,&quot; );&#13;&#10;fout.WriteLine( &quot;  \&quot;dataPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;data\&quot;,&quot; );&#13;&#10;&#13;&#10;// copy rest of settings&#13;&#10;while( !fin.AtEndOfStream ) {&#13;&#10;&#9;fout.WriteLine( fin.ReadLine() );&#13;&#10;}&#13;&#10;&#13;&#10;fin.Close();&#13;&#10;fout.Close();&#13;&#10;" AdditionalSeq="AI_DATA_SETTER_3"/>
+    <ROW Action="CustomizeSettingsJsonScript" Type="3109" Target="Script Text" TargetUnformatted="var actionData = Session.Property(&quot;CustomActionData&quot;);&#13;&#10;var actionDataArray = actionData.split(&quot;|&quot;);&#13;&#10;var appDir = actionDataArray[0];&#13;&#10;var dataFolder = actionDataArray[1] + actionDataArray[2] + &quot;\\&quot;;&#13;&#10;&#13;&#10;var ForReading = 1, ForWriting = 2, ForAppending = 8;&#13;&#10;var fso = new ActiveXObject(&quot;Scripting.FileSystemObject&quot;);&#13;&#10;&#13;&#10;// Create basic %APPDIR%\settings.json with path to real settings.json in dataFolder&#13;&#10;var fts = fso.OpenTextFile(appDir + &quot;settings.json&quot;, ForWriting, true);&#13;&#10;&#13;&#10;fts.WriteLine( &quot;{&quot; );&#13;&#10;// We need to escape Windows path backslashes to keep JSON valid&#13;&#10;fts.WriteLine( &quot;  \&quot;userPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;\&quot;&quot; );&#13;&#10;fts.WriteLine( &quot;}&quot; );&#13;&#10;&#13;&#10;fts.Close();&#13;&#10;&#13;&#10;// Make copy&#13;&#10;fso.CopyFile(dataFolder + &quot;settings.json&quot;, dataFolder + &quot;settings-orig.json&quot;, true); // overwrite&#13;&#10;&#13;&#10;// Rewrite settings.json to update repository path&#13;&#10;var fin = fso.OpenTextFile(dataFolder + &quot;settings-orig.json&quot;, ForReading, false);&#13;&#10;var fout = fso.OpenTextFile(dataFolder + &quot;settings.json&quot;, ForWriting, true);&#13;&#10;&#13;&#10;// First line should contain opening brace&#13;&#10;fout.WriteLine( fin.ReadLine() );&#13;&#10;&#13;&#10;// Append our entries&#13;&#10;fout.WriteLine( &quot;  \&quot;repositoryPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;db\&quot;,&quot; );&#13;&#10;fout.WriteLine( &quot;  \&quot;dataPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;data\&quot;,&quot; );&#13;&#10;fout.WriteLine( &quot;  \&quot;walletsPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;wallets\&quot;,&quot; );&#13;&#10;fout.WriteLine( &quot;  \&quot;listsPath\&quot;: \&quot;&quot; + dataFolder.split(&apos;\\&apos;).join(&apos;\\\\&apos;) + &quot;lists\&quot;,&quot; );&#13;&#10;&#13;&#10;// copy rest of settings&#13;&#10;while( !fin.AtEndOfStream ) {&#13;&#10;&#9;fout.WriteLine( fin.ReadLine() );&#13;&#10;}&#13;&#10;&#13;&#10;fin.Close();&#13;&#10;fout.Close();&#13;&#10;" AdditionalSeq="AI_DATA_SETTER_3"/>
     <ROW Action="DetectRunningProcess" Type="1" Source="aicustact.dll" Target="DetectProcess" Options="3" AdditionalSeq="AI_DATA_SETTER_8"/>
     <ROW Action="DetectW32Time" Type="1" Source="aicustact.dll" Target="DetectService" Options="3" AdditionalSeq="AI_DATA_SETTER_11"/>
     <ROW Action="NTP_config" Type="3090" Source="ntpcfg.bat"/>

lib/org/ciyam/AT/1.4.0/AT-1.4.0.pom

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>org.ciyam</groupId>
+  <artifactId>AT</artifactId>
+  <version>1.4.0</version>
+  <description>POM was created from install:install-file</description>
+</project>

lib/org/ciyam/AT/maven-metadata-local.xml

@@ -3,14 +3,15 @@
   <groupId>org.ciyam</groupId>
   <artifactId>AT</artifactId>
   <versioning>
-    <release>1.3.8</release>
+    <release>1.4.0</release>
     <versions>
       <version>1.3.4</version>
       <version>1.3.5</version>
       <version>1.3.6</version>
       <version>1.3.7</version>
       <version>1.3.8</version>
+      <version>1.4.0</version>
     </versions>
-    <lastUpdated>20200925114415</lastUpdated>
+    <lastUpdated>20221105114346</lastUpdated>
   </versioning>
 </metadata>

pom.xml

@@ -3,7 +3,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>org.qortal</groupId>
 	<artifactId>qortal</artifactId>
-	<version>3.5.0</version>
+	<version>3.8.4</version>
 	<packaging>jar</packaging>
 	<properties>
 		<skipTests>true</skipTests>
@@ -11,7 +11,7 @@
 		<bitcoinj.version>0.15.10</bitcoinj.version>
 		<bouncycastle.version>1.69</bouncycastle.version>
 		<build.timestamp>${maven.build.timestamp}</build.timestamp>
-		<ciyam-at.version>1.3.8</ciyam-at.version>
+		<ciyam-at.version>1.4.0</ciyam-at.version>
 		<commons-net.version>3.6</commons-net.version>
 		<commons-text.version>1.8</commons-text.version>
 		<commons-io.version>2.6</commons-io.version>

src/main/java/org/qortal/account/Account.java

@@ -211,7 +211,8 @@ public class Account {
 		if (level != null && level >= BlockChain.getInstance().getMinAccountLevelToMint())
 			return true;
 
-		if (Account.isFounder(accountData.getFlags()))
+		// Founders can always mint, unless they have a penalty
+		if (Account.isFounder(accountData.getFlags()) && accountData.getBlocksMintedPenalty() == 0)
 			return true;
 
 		return false;
@@ -222,6 +223,11 @@ public class Account {
 		return this.repository.getAccountRepository().getMintedBlockCount(this.address);
 	}
 
+	/** Returns account's blockMintedPenalty or null if account not found in repository. */
+	public Integer getBlocksMintedPenalty() throws DataException {
+		return this.repository.getAccountRepository().getBlocksMintedPenaltyCount(this.address);
+	}
+
 
 	/** Returns whether account can build reward-shares.
 	 * <p>
@@ -243,7 +249,7 @@ public class Account {
 		if (level != null && level >= BlockChain.getInstance().getMinAccountLevelToRewardShare())
 			return true;
 
-		if (Account.isFounder(accountData.getFlags()))
+		if (Account.isFounder(accountData.getFlags()) && accountData.getBlocksMintedPenalty() == 0)
 			return true;
 
 		return false;
@@ -271,7 +277,7 @@ public class Account {
 	/**
 	 * Returns 'effective' minting level, or zero if account does not exist/cannot mint.
 	 * <p>
-	 * For founder accounts, this returns "founderEffectiveMintingLevel" from blockchain config.
+	 * For founder accounts with no penalty, this returns "founderEffectiveMintingLevel" from blockchain config.
 	 * 
 	 * @return 0+
 	 * @throws DataException
@@ -281,7 +287,8 @@ public class Account {
 		if (accountData == null)
 			return 0;
 
-		if (Account.isFounder(accountData.getFlags()))
+		// Founders are assigned a different effective minting level, as long as they have no penalty
+		if (Account.isFounder(accountData.getFlags()) && accountData.getBlocksMintedPenalty() == 0)
 			return BlockChain.getInstance().getFounderEffectiveMintingLevel();
 
 		return accountData.getLevel();
@@ -289,8 +296,6 @@ public class Account {
 
 	/**
 	 * Returns 'effective' minting level, or zero if reward-share does not exist.
-	 * <p>
-	 * this is being used on src/main/java/org/qortal/api/resource/AddressesResource.java to fulfil the online accounts api call
 	 * 
 	 * @param repository
 	 * @param rewardSharePublicKey
@@ -309,7 +314,7 @@ public class Account {
 	/**
 	 * Returns 'effective' minting level, with a fix for the zero level.
 	 * <p>
-	 * For founder accounts, this returns "founderEffectiveMintingLevel" from blockchain config.
+	 * For founder accounts with no penalty, this returns "founderEffectiveMintingLevel" from blockchain config.
 	 *
 	 * @param repository
 	 * @param rewardSharePublicKey
@@ -322,7 +327,7 @@ public class Account {
 		if (rewardShareData == null)
 			return 0;
 
-		else if(!rewardShareData.getMinter().equals(rewardShareData.getRecipient()))//the minter is different than the recipient this means sponsorship
+		else if (!rewardShareData.getMinter().equals(rewardShareData.getRecipient())) // Sponsorship reward share
 			return 0;
 
 		Account rewardShareMinter = new Account(repository, rewardShareData.getMinter());

src/main/java/org/qortal/account/SelfSponsorshipAlgoV1.java

@@ -0,0 +1,367 @@
+package org.qortal.account;
+
+import org.qortal.api.resource.TransactionsResource;
+import org.qortal.asset.Asset;
+import org.qortal.data.account.AccountData;
+import org.qortal.data.naming.NameData;
+import org.qortal.data.transaction.*;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.transaction.Transaction.TransactionType;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+public class SelfSponsorshipAlgoV1 {
+
+    private final Repository repository;
+    private final String address;
+    private final AccountData accountData;
+    private final long snapshotTimestamp;
+    private final boolean override;
+
+    private int registeredNameCount = 0;
+    private int suspiciousCount = 0;
+    private int suspiciousPercent = 0;
+    private int consolidationCount = 0;
+    private int bulkIssuanceCount = 0;
+    private int recentSponsorshipCount = 0;
+
+    private List<RewardShareTransactionData> sponsorshipRewardShares = new ArrayList<>();
+    private final Map<String, List<TransactionData>> paymentsByAddress = new HashMap<>();
+    private final Set<String> sponsees = new LinkedHashSet<>();
+    private Set<String> consolidatedAddresses = new LinkedHashSet<>();
+    private final Set<String> zeroTransactionAddreses = new LinkedHashSet<>();
+    private final Set<String> penaltyAddresses = new LinkedHashSet<>();
+
+    public SelfSponsorshipAlgoV1(Repository repository, String address, long snapshotTimestamp, boolean override) throws DataException {
+        this.repository = repository;
+        this.address = address;
+        this.accountData = this.repository.getAccountRepository().getAccount(this.address);
+        this.snapshotTimestamp = snapshotTimestamp;
+        this.override = override;
+    }
+
+    public String getAddress() {
+        return this.address;
+    }
+
+    public Set<String> getPenaltyAddresses() {
+        return this.penaltyAddresses;
+    }
+
+
+    public void run() throws DataException {
+        if (this.accountData == null) {
+            // Nothing to do
+            return;
+        }
+
+        this.fetchSponsorshipRewardShares();
+        if (this.sponsorshipRewardShares.isEmpty()) {
+            // Nothing to do
+            return;
+        }
+
+        this.findConsolidatedRewards();
+        this.findBulkIssuance();
+        this.findRegisteredNameCount();
+        this.findRecentSponsorshipCount();
+
+        int score = this.calculateScore();
+        if (score <= 0 && !override) {
+            return;
+        }
+
+        String newAddress = this.getDestinationAccount(this.address);
+        while (newAddress != null) {
+            // Found destination account
+            this.penaltyAddresses.add(newAddress);
+
+            // Run algo for this address, but in "override" mode because it has already been flagged
+            SelfSponsorshipAlgoV1 algoV1 = new SelfSponsorshipAlgoV1(this.repository, newAddress, this.snapshotTimestamp, true);
+            algoV1.run();
+            this.penaltyAddresses.addAll(algoV1.getPenaltyAddresses());
+
+            newAddress = this.getDestinationAccount(newAddress);
+        }
+
+        this.penaltyAddresses.add(this.address);
+
+        if (this.override || this.recentSponsorshipCount < 20) {
+            this.penaltyAddresses.addAll(this.consolidatedAddresses);
+            this.penaltyAddresses.addAll(this.zeroTransactionAddreses);
+        }
+        else {
+            this.penaltyAddresses.addAll(this.sponsees);
+        }
+    }
+
+    private String getDestinationAccount(String address) throws DataException {
+        List<TransactionData> transferPrivsTransactions = fetchTransferPrivsForAddress(address);
+        if (transferPrivsTransactions.isEmpty()) {
+            // No TRANSFER_PRIVS transactions for this address
+            return null;
+        }
+
+        AccountData accountData = this.repository.getAccountRepository().getAccount(address);
+        if (accountData == null) {
+            return null;
+        }
+
+        for (TransactionData transactionData : transferPrivsTransactions) {
+            TransferPrivsTransactionData transferPrivsTransactionData = (TransferPrivsTransactionData) transactionData;
+            if (Arrays.equals(transferPrivsTransactionData.getSenderPublicKey(), accountData.getPublicKey())) {
+                return transferPrivsTransactionData.getRecipient();
+            }
+        }
+
+        return null;
+    }
+
+    private void findConsolidatedRewards() throws DataException {
+        List<String> sponseesThatSentRewards = new ArrayList<>();
+        Map<String, Integer> paymentRecipients = new HashMap<>();
+
+        // Collect outgoing payments of each sponsee
+        for (String sponseeAddress : this.sponsees) {
+
+            // Firstly fetch all payments for address, since the functions below depend on this data
+            this.fetchPaymentsForAddress(sponseeAddress);
+
+            // Check if the address has zero relevant transactions
+            if (this.hasZeroTransactions(sponseeAddress)) {
+                this.zeroTransactionAddreses.add(sponseeAddress);
+            }
+
+            // Get payment recipients
+            List<String> allPaymentRecipients = this.fetchOutgoingPaymentRecipientsForAddress(sponseeAddress);
+            if (allPaymentRecipients.isEmpty()) {
+                continue;
+            }
+            sponseesThatSentRewards.add(sponseeAddress);
+
+            List<String> addressesPaidByThisSponsee = new ArrayList<>();
+            for (String paymentRecipient : allPaymentRecipients) {
+                if (addressesPaidByThisSponsee.contains(paymentRecipient)) {
+                    // We already tracked this association - don't allow multiple to stack up
+                    continue;
+                }
+                addressesPaidByThisSponsee.add(paymentRecipient);
+
+                // Increment count for this recipient, or initialize to 1 if not present
+                if (paymentRecipients.computeIfPresent(paymentRecipient, (k, v) -> v + 1) == null) {
+                    paymentRecipients.put(paymentRecipient, 1);
+                }
+            }
+
+        }
+
+        // Exclude addresses with a low number of payments
+        Map<String, Integer> filteredPaymentRecipients = paymentRecipients.entrySet().stream()
+                .filter(p -> p.getValue() != null && p.getValue() >= 10)
+                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+
+        // Now check how many sponsees have sent to this subset of addresses
+        Map<String, Integer> sponseesThatConsolidatedRewards = new HashMap<>();
+        for (String sponseeAddress : sponseesThatSentRewards) {
+            List<String> allPaymentRecipients = this.fetchOutgoingPaymentRecipientsForAddress(sponseeAddress);
+            // Remove any that aren't to one of the flagged recipients (i.e. consolidation)
+            allPaymentRecipients.removeIf(r -> !filteredPaymentRecipients.containsKey(r));
+
+            int count = allPaymentRecipients.size();
+            if (count == 0) {
+                continue;
+            }
+            if (sponseesThatConsolidatedRewards.computeIfPresent(sponseeAddress, (k, v) -> v + count) == null) {
+                sponseesThatConsolidatedRewards.put(sponseeAddress, count);
+            }
+        }
+
+        // Remove sponsees that have only sent a low number of payments to the filtered addresses
+        Map<String, Integer> filteredSponseesThatConsolidatedRewards = sponseesThatConsolidatedRewards.entrySet().stream()
+                .filter(p -> p.getValue() != null && p.getValue() >= 2)
+                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+
+        this.consolidationCount = sponseesThatConsolidatedRewards.size();
+        this.consolidatedAddresses = new LinkedHashSet<>(filteredSponseesThatConsolidatedRewards.keySet());
+        this.suspiciousCount = this.consolidationCount + this.zeroTransactionAddreses.size();
+        this.suspiciousPercent = (int)(this.suspiciousCount / (float) this.sponsees.size() * 100);
+    }
+
+    private void findBulkIssuance() {
+        Long lastTimestamp = null;
+        for (RewardShareTransactionData rewardShareTransactionData : sponsorshipRewardShares) {
+            long timestamp = rewardShareTransactionData.getTimestamp();
+            if (timestamp >= this.snapshotTimestamp) {
+                continue;
+            }
+
+            if (lastTimestamp != null) {
+                if (timestamp - lastTimestamp < 3*60*1000L) {
+                    this.bulkIssuanceCount++;
+                }
+            }
+            lastTimestamp = timestamp;
+        }
+    }
+
+    private void findRegisteredNameCount() throws DataException {
+        int registeredNameCount = 0;
+        for (String sponseeAddress : sponsees) {
+            List<NameData> names = repository.getNameRepository().getNamesByOwner(sponseeAddress);
+            for (NameData name : names) {
+                if (name.getRegistered() < this.snapshotTimestamp) {
+                    registeredNameCount++;
+                    break;
+                }
+            }
+        }
+        this.registeredNameCount = registeredNameCount;
+    }
+
+    private void findRecentSponsorshipCount() {
+        final long referenceTimestamp = this.snapshotTimestamp - (365 * 24 * 60 * 60 * 1000L);
+        int recentSponsorshipCount = 0;
+        for (RewardShareTransactionData rewardShare : sponsorshipRewardShares) {
+            if (rewardShare.getTimestamp() >= referenceTimestamp) {
+                recentSponsorshipCount++;
+            }
+        }
+        this.recentSponsorshipCount = recentSponsorshipCount;
+    }
+
+    private int calculateScore() {
+        final int suspiciousMultiplier = (this.suspiciousCount >= 100) ? this.suspiciousPercent : 1;
+        final int nameMultiplier = (this.sponsees.size() >= 50 && this.registeredNameCount == 0) ? 2 : 1;
+        final int consolidationMultiplier = Math.max(this.consolidationCount, 1);
+        final int bulkIssuanceMultiplier = Math.max(this.bulkIssuanceCount / 2, 1);
+        final int offset = 9;
+        return suspiciousMultiplier * nameMultiplier * consolidationMultiplier * bulkIssuanceMultiplier - offset;
+    }
+
+    private void fetchSponsorshipRewardShares() throws DataException {
+        List<RewardShareTransactionData> sponsorshipRewardShares = new ArrayList<>();
+
+        // Define relevant transactions
+        List<TransactionType> txTypes = List.of(TransactionType.REWARD_SHARE);
+        List<TransactionData> transactionDataList = fetchTransactions(repository, txTypes, this.address, false);
+
+        for (TransactionData transactionData : transactionDataList) {
+            if (transactionData.getType() != TransactionType.REWARD_SHARE) {
+                continue;
+            }
+
+            RewardShareTransactionData rewardShareTransactionData = (RewardShareTransactionData) transactionData;
+
+            // Skip removals
+            if (rewardShareTransactionData.getSharePercent() < 0) {
+                continue;
+            }
+
+            // Skip if not sponsored by this account
+            if (!Arrays.equals(rewardShareTransactionData.getCreatorPublicKey(), accountData.getPublicKey())) {
+                continue;
+            }
+
+            // Skip self shares
+            if (Objects.equals(rewardShareTransactionData.getRecipient(), this.address)) {
+                continue;
+            }
+
+            boolean duplicateFound = false;
+            for (RewardShareTransactionData existingRewardShare : sponsorshipRewardShares) {
+                if (Objects.equals(existingRewardShare.getRecipient(), rewardShareTransactionData.getRecipient())) {
+                    // Duplicate
+                    duplicateFound = true;
+                    break;
+                }
+            }
+            if (!duplicateFound) {
+                sponsorshipRewardShares.add(rewardShareTransactionData);
+                this.sponsees.add(rewardShareTransactionData.getRecipient());
+            }
+        }
+
+        this.sponsorshipRewardShares = sponsorshipRewardShares;
+    }
+
+    private List<TransactionData> fetchTransferPrivsForAddress(String address) throws DataException {
+        return fetchTransactions(repository,
+                List.of(TransactionType.TRANSFER_PRIVS),
+                address, true);
+    }
+
+    private void fetchPaymentsForAddress(String address) throws DataException {
+        List<TransactionData> payments = fetchTransactions(repository,
+                Arrays.asList(TransactionType.PAYMENT, TransactionType.TRANSFER_ASSET),
+                address, false);
+        this.paymentsByAddress.put(address, payments);
+    }
+
+    private List<String> fetchOutgoingPaymentRecipientsForAddress(String address) {
+        List<String> outgoingPaymentRecipients = new ArrayList<>();
+
+        List<TransactionData> transactionDataList = this.paymentsByAddress.get(address);
+        if (transactionDataList == null) transactionDataList = new ArrayList<>();
+        transactionDataList.removeIf(t -> t.getTimestamp() >= this.snapshotTimestamp);
+        for (TransactionData transactionData : transactionDataList) {
+            switch (transactionData.getType()) {
+
+                case PAYMENT:
+                    PaymentTransactionData paymentTransactionData = (PaymentTransactionData) transactionData;
+                    if (!Objects.equals(paymentTransactionData.getRecipient(), address)) {
+                        // Outgoing payment from this account
+                        outgoingPaymentRecipients.add(paymentTransactionData.getRecipient());
+                    }
+                    break;
+
+                case TRANSFER_ASSET:
+                    TransferAssetTransactionData transferAssetTransactionData = (TransferAssetTransactionData) transactionData;
+                    if (transferAssetTransactionData.getAssetId() == Asset.QORT) {
+                        if (!Objects.equals(transferAssetTransactionData.getRecipient(), address)) {
+                            // Outgoing payment from this account
+                            outgoingPaymentRecipients.add(transferAssetTransactionData.getRecipient());
+                        }
+                    }
+                    break;
+
+                default:
+                    break;
+            }
+        }
+
+        return outgoingPaymentRecipients;
+    }
+
+    private boolean hasZeroTransactions(String address) {
+        List<TransactionData> transactionDataList = this.paymentsByAddress.get(address);
+        if (transactionDataList == null) {
+            return true;
+        }
+        transactionDataList.removeIf(t -> t.getTimestamp() >= this.snapshotTimestamp);
+        return transactionDataList.size() == 0;
+    }
+
+    private static List<TransactionData> fetchTransactions(Repository repository, List<TransactionType> txTypes, String address, boolean reverse) throws DataException {
+        // Fetch all relevant transactions for this account
+        List<byte[]> signatures = repository.getTransactionRepository()
+                .getSignaturesMatchingCriteria(null, null, null, txTypes,
+                        null, null, address, TransactionsResource.ConfirmationStatus.CONFIRMED,
+                        null, null, reverse);
+
+        List<TransactionData> transactionDataList = new ArrayList<>();
+
+        for (byte[] signature : signatures) {
+            // Fetch transaction data
+            TransactionData transactionData = repository.getTransactionRepository().fromSignature(signature);
+            if (transactionData == null) {
+                continue;
+            }
+            transactionDataList.add(transactionData);
+        }
+
+        return transactionDataList;
+    }
+
+}

src/main/java/org/qortal/api/model/AccountPenaltyStats.java

@@ -0,0 +1,56 @@
+package org.qortal.api.model;
+
+import org.qortal.block.SelfSponsorshipAlgoV1Block;
+import org.qortal.data.account.AccountData;
+import org.qortal.data.naming.NameData;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlElement;
+import java.util.ArrayList;
+import java.util.List;
+
+@XmlAccessorType(XmlAccessType.FIELD)
+public class AccountPenaltyStats {
+
+	public Integer totalPenalties;
+	public Integer maxPenalty;
+	public Integer minPenalty;
+	public String penaltyHash;
+
+	protected AccountPenaltyStats() {
+	}
+
+	public AccountPenaltyStats(Integer totalPenalties, Integer maxPenalty, Integer minPenalty, String penaltyHash) {
+		this.totalPenalties = totalPenalties;
+		this.maxPenalty = maxPenalty;
+		this.minPenalty = minPenalty;
+		this.penaltyHash = penaltyHash;
+	}
+
+	public static AccountPenaltyStats fromAccounts(List<AccountData> accounts) {
+		int totalPenalties = 0;
+		Integer maxPenalty = null;
+		Integer minPenalty = null;
+
+		List<String> addresses = new ArrayList<>();
+		for (AccountData accountData : accounts) {
+			int penalty = accountData.getBlocksMintedPenalty();
+			addresses.add(accountData.getAddress());
+			totalPenalties++;
+
+			// Penalties are expressed as a negative number, so the min and the max are reversed here
+			if (maxPenalty == null || penalty < maxPenalty) maxPenalty = penalty;
+			if (minPenalty == null || penalty > minPenalty) minPenalty = penalty;
+		}
+
+		String penaltyHash = SelfSponsorshipAlgoV1Block.getHash(addresses);
+		return new AccountPenaltyStats(totalPenalties, maxPenalty, minPenalty, penaltyHash);
+	}
+
+
+	@Override
+	public String toString() {
+		return String.format("totalPenalties: %d, maxPenalty: %d, minPenalty: %d, penaltyHash: %s", totalPenalties, maxPenalty, minPenalty, penaltyHash == null ? "null" : penaltyHash);
+	}
+}

src/main/java/org/qortal/api/model/ConnectedPeer.java

@@ -1,7 +1,8 @@
 package org.qortal.api.model;
 
 import io.swagger.v3.oas.annotations.media.Schema;
-import org.qortal.data.network.PeerChainTipData;
+import org.qortal.controller.Controller;
+import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.network.PeerData;
 import org.qortal.network.Handshake;
 import org.qortal.network.Peer;
@@ -36,6 +37,7 @@ public class ConnectedPeer {
     public Long lastBlockTimestamp;
     public UUID connectionId;
     public String age;
+    public Boolean isTooDivergent;
 
     protected ConnectedPeer() {
     }
@@ -63,11 +65,16 @@ public class ConnectedPeer {
             this.age = "connecting...";
         }
 
-        PeerChainTipData peerChainTipData = peer.getChainTipData();
+        BlockSummaryData peerChainTipData = peer.getChainTipData();
         if (peerChainTipData != null) {
-            this.lastHeight = peerChainTipData.getLastHeight();
-            this.lastBlockSignature = peerChainTipData.getLastBlockSignature();
-            this.lastBlockTimestamp = peerChainTipData.getLastBlockTimestamp();
+            this.lastHeight = peerChainTipData.getHeight();
+            this.lastBlockSignature = peerChainTipData.getSignature();
+            this.lastBlockTimestamp = peerChainTipData.getTimestamp();
+        }
+
+        // Only include isTooDivergent decision if we've had the opportunity to request block summaries this peer
+        if (peer.getLastTooDivergentTime() != null) {
+            this.isTooDivergent = Controller.wasRecentlyTooDivergent.test(peer);
         }
     }
 

src/main/java/org/qortal/api/resource/AddressesResource.java

@@ -14,6 +14,7 @@ import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
+import java.util.stream.Collectors;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.*;
@@ -27,6 +28,7 @@ import org.qortal.api.ApiErrors;
 import org.qortal.api.ApiException;
 import org.qortal.api.ApiExceptionFactory;
 import org.qortal.api.Security;
+import org.qortal.api.model.AccountPenaltyStats;
 import org.qortal.api.model.ApiOnlineAccount;
 import org.qortal.api.model.RewardShareKeyRequest;
 import org.qortal.asset.Asset;
@@ -34,6 +36,7 @@ import org.qortal.controller.LiteNode;
 import org.qortal.controller.OnlineAccountsManager;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.account.AccountData;
+import org.qortal.data.account.AccountPenaltyData;
 import org.qortal.data.account.RewardShareData;
 import org.qortal.data.network.OnlineAccountData;
 import org.qortal.data.network.OnlineAccountLevel;
@@ -205,6 +208,10 @@ public class AddressesResource {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			List<OnlineAccountLevel> onlineAccountLevels = new ArrayList<>();
 
+			// Prepopulate all levels
+			for (int i=0; i<=10; i++)
+				onlineAccountLevels.add(new OnlineAccountLevel(i, 0));
+
 			for (OnlineAccountData onlineAccountData : onlineAccounts) {
 				try {
 					final int minterLevel = Account.getRewardShareEffectiveMintingLevelIncludingLevelZero(repository, onlineAccountData.getPublicKey());
@@ -467,6 +474,54 @@ public class AddressesResource {
 		}
 	}
 
+	@GET
+	@Path("/penalties")
+	@Operation(
+			summary = "Get addresses with penalties",
+			description = "Returns a list of accounts with a blocksMintedPenalty",
+			responses = {
+					@ApiResponse(
+							description = "accounts with penalties",
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, array = @ArraySchema(schema = @Schema(implementation = AccountPenaltyData.class)))
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public List<AccountPenaltyData> getAccountsWithPenalties() {
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<AccountData> accounts = repository.getAccountRepository().getPenaltyAccounts();
+			List<AccountPenaltyData> penalties = accounts.stream().map(a -> new AccountPenaltyData(a.getAddress(), a.getBlocksMintedPenalty())).collect(Collectors.toList());
+
+			return penalties;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
+	@GET
+	@Path("/penalties/stats")
+	@Operation(
+			summary = "Get stats about current penalties",
+			responses = {
+					@ApiResponse(
+							description = "aggregated stats about accounts with penalties",
+							content = @Content(mediaType = MediaType.APPLICATION_JSON, array = @ArraySchema(schema = @Schema(implementation = AccountPenaltyStats.class)))
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public AccountPenaltyStats getPenaltyStats() {
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<AccountData> accounts = repository.getAccountRepository().getPenaltyAccounts();
+			return AccountPenaltyStats.fromAccounts(accounts);
+
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@POST
 	@Path("/publicize")
 	@Operation(

src/main/java/org/qortal/api/resource/AdminResource.java

@@ -728,6 +728,49 @@ public class AdminResource {
 		}
 	}
 
+	@POST
+	@Path("/repository/importarchivedtrades")
+	@Operation(
+			summary = "Imports archived trades from TradeBotStatesArchive.json",
+			description = "This can be used to recover trades that exist in the archive only, which may be needed if a<br />" +
+					"problem occurred during the proof-of-work computation stage of a buy request.",
+			responses = {
+					@ApiResponse(
+							content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "boolean"))
+					)
+			}
+	)
+	@ApiErrors({ApiError.REPOSITORY_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public boolean importArchivedTrades(@HeaderParam(Security.API_KEY_HEADER) String apiKey) {
+		Security.checkApiCallAllowed(request);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
+
+			blockchainLock.lockInterruptibly();
+
+			try {
+				repository.importDataFromFile("qortal-backup/TradeBotStatesArchive.json");
+				repository.saveChanges();
+
+				return true;
+
+			} catch (IOException e) {
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA, e);
+
+			} finally {
+				blockchainLock.unlock();
+			}
+		} catch (InterruptedException e) {
+			// We couldn't lock blockchain to perform import
+			return false;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
+
 
 	@POST
 	@Path("/apikey/generate")

src/main/java/org/qortal/api/resource/ArbitraryResource.java

@@ -15,6 +15,7 @@ import java.io.*;
 import java.nio.file.Files;
 import java.nio.file.Paths;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 
 import javax.servlet.ServletContext;
@@ -44,6 +45,7 @@ import org.qortal.data.arbitrary.*;
 import org.qortal.data.naming.NameData;
 import org.qortal.data.transaction.ArbitraryTransactionData;
 import org.qortal.data.transaction.TransactionData;
+import org.qortal.list.ResourceListManager;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
@@ -91,6 +93,7 @@ public class ArbitraryResource {
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
 			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse,
+			@Parameter(description = "Filter names by list") @QueryParam("namefilter") String nameFilter,
 			@Parameter(description = "Include status") @QueryParam("includestatus") Boolean includeStatus,
 			@Parameter(description = "Include metadata") @QueryParam("includemetadata") Boolean includeMetadata) {
 
@@ -107,8 +110,18 @@ public class ArbitraryResource {
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "identifier cannot be specified when requesting a default resource");
 			}
 
+			// Load filter from list if needed
+			List<String> names = null;
+			if (nameFilter != null) {
+				names = ResourceListManager.getInstance().getStringsInList(nameFilter);
+				if (names.isEmpty()) {
+					// List doesn't exist or is empty - so there will be no matches
+					return new ArrayList<>();
+				}
+			}
+
 			List<ArbitraryResourceInfo> resources = repository.getArbitraryRepository()
-					.getArbitraryResources(service, identifier, null, defaultRes, limit, offset, reverse);
+					.getArbitraryResources(service, identifier, names, defaultRes, limit, offset, reverse);
 
 			if (resources == null) {
 				return new ArrayList<>();
@@ -216,7 +229,7 @@ public class ArbitraryResource {
 				String name = creatorName.name;
 				if (name != null) {
 					List<ArbitraryResourceInfo> resources = repository.getArbitraryRepository()
-							.getArbitraryResources(service, identifier, name, defaultRes, null, null, reverse);
+							.getArbitraryResources(service, identifier, Arrays.asList(name), defaultRes, null, null, reverse);
 
 					if (includeStatus != null && includeStatus) {
 						resources = this.addStatusToResources(resources);

src/main/java/org/qortal/api/resource/ChatResource.java

@@ -69,6 +69,9 @@ public class ChatResource {
 	public List<ChatMessage> searchChat(@QueryParam("before") Long before, @QueryParam("after") Long after,
 			@QueryParam("txGroupId") Integer txGroupId,
 			@QueryParam("involving") List<String> involvingAddresses,
+			@QueryParam("reference") String reference,
+			@QueryParam("chatreference") String chatReference,
+			@QueryParam("haschatreference") Boolean hasChatReference,
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
 			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse) {
@@ -87,11 +90,22 @@ public class ChatResource {
 		if (after != null && after < 1500000000000L)
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
+		byte[] referenceBytes = null;
+		if (reference != null)
+			referenceBytes = Base58.decode(reference);
+
+		byte[] chatReferenceBytes = null;
+		if (chatReference != null)
+			chatReferenceBytes = Base58.decode(chatReference);
+
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			return repository.getChatRepository().getMessagesMatchingCriteria(
 					before,
 					after,
 					txGroupId,
+					referenceBytes,
+					chatReferenceBytes,
+					hasChatReference,
 					involvingAddresses,
 					limit, offset, reverse);
 		} catch (DataException e) {
@@ -99,6 +113,38 @@ public class ChatResource {
 		}
 	}
 
+	@GET
+	@Path("/message/{signature}")
+	@Operation(
+			summary = "Find chat message by signature",
+			responses = {
+					@ApiResponse(
+							description = "CHAT message",
+							content = @Content(
+										schema = @Schema(
+												implementation = ChatMessage.class
+										)
+							)
+					)
+			}
+	)
+	@ApiErrors({ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public ChatMessage getMessageBySignature(@PathParam("signature") String signature58) {
+		byte[] signature = Base58.decode(signature58);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			ChatTransactionData chatTransactionData = (ChatTransactionData) repository.getTransactionRepository().fromSignature(signature);
+			if (chatTransactionData == null) {
+				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Message not found");
+			}
+
+			return repository.getChatRepository().toChatMessage(chatTransactionData);
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@GET
 	@Path("/active/{address}")
 	@Operation(

src/main/java/org/qortal/api/resource/CrossChainHtlcResource.java

@@ -1,5 +1,6 @@
 package org.qortal.api.resource;
 
+import com.google.common.hash.HashCode;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.media.Content;
 import io.swagger.v3.oas.annotations.media.Schema;
@@ -9,6 +10,8 @@ import io.swagger.v3.oas.annotations.tags.Tag;
 
 import java.math.BigDecimal;
 import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.*;
@@ -284,6 +287,12 @@ public class CrossChainHtlcResource {
 					continue;
 				}
 
+				Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
+				if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+					LOGGER.info("Skipping AT {} because ARRR is currently unsupported", atAddress);
+					continue;
+				}
+
 				CrossChainTradeData crossChainTradeData = acct.populateTradeData(repository, atData);
 				if (crossChainTradeData == null) {
 					LOGGER.info("Couldn't find crosschain trade data for AT {}", atAddress);
@@ -363,10 +372,6 @@ public class CrossChainHtlcResource {
 			// Use secret-A to redeem P2SH-A
 
 			Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
-			if (bitcoiny.getClass() == Bitcoin.class) {
-				LOGGER.info("Redeeming a Bitcoin HTLC is not yet supported");
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
-			}
 
 			int lockTime = crossChainTradeData.lockTimeA;
 			byte[] redeemScriptA = BitcoinyHTLC.buildScript(crossChainTradeData.partnerForeignPKH, lockTime, crossChainTradeData.creatorForeignPKH, crossChainTradeData.hashOfSecretA);
@@ -574,70 +579,108 @@ public class CrossChainHtlcResource {
 			// If the AT is "finished" then it will have a zero balance
 			// In these cases we should avoid HTLC refunds if tbe QORT haven't been returned to the seller
 			if (atData.getIsFinished() && crossChainTradeData.mode != AcctMode.REFUNDED && crossChainTradeData.mode != AcctMode.CANCELLED) {
-				LOGGER.info(String.format("Skipping AT %s because the QORT has already been redemed", atAddress));
+				LOGGER.info(String.format("Skipping AT %s because the QORT has already been redeemed by the buyer", atAddress));
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 			}
 
 			List<TradeBotData> allTradeBotData = repository.getCrossChainRepository().getAllTradeBotData();
-			TradeBotData tradeBotData = allTradeBotData.stream().filter(tradeBotDataItem -> tradeBotDataItem.getAtAddress().equals(atAddress)).findFirst().orElse(null);
-			if (tradeBotData == null)
+			List<TradeBotData> tradeBotDataList = allTradeBotData.stream().filter(tradeBotDataItem -> tradeBotDataItem.getAtAddress().equals(atAddress)).collect(Collectors.toList());
+			if (tradeBotDataList == null || tradeBotDataList.isEmpty())
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
-			Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
-			if (bitcoiny.getClass() == Bitcoin.class) {
-				LOGGER.info("Refunding a Bitcoin HTLC is not yet supported");
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
-			}
+			// Loop through all matching entries for this AT address, as there might be more than one
+			for (TradeBotData tradeBotData : tradeBotDataList) {
 
-			int lockTime = tradeBotData.getLockTimeA();
+				if (tradeBotData == null)
+					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
-			// We can't refund P2SH-A until lockTime-A has passed
-			if (NTP.getTime() <= lockTime * 1000L)
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
+				int lockTime = tradeBotData.getLockTimeA();
 
-			// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
-			int medianBlockTime = bitcoiny.getMedianBlockTime();
-			if (medianBlockTime <= lockTime)
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				// We can't refund P2SH-A until lockTime-A has passed
+				if (NTP.getTime() <= lockTime * 1000L)
+					continue;
 
-			byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-			String p2shAddressA = bitcoiny.deriveP2shAddress(redeemScriptA);
-			LOGGER.info(String.format("Refunding P2SH address: %s", p2shAddressA));
+				// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
+				int medianBlockTime = bitcoiny.getMedianBlockTime();
+				if (medianBlockTime <= lockTime)
+					continue;
 
-			// Fee for redeem/refund is subtracted from P2SH-A balance.
-			long feeTimestamp = calcFeeTimestamp(lockTime, crossChainTradeData.tradeTimeout);
-			long p2shFee = bitcoiny.getP2shFee(feeTimestamp);
-			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+				// Fee for redeem/refund is subtracted from P2SH-A balance.
+				long feeTimestamp = calcFeeTimestamp(lockTime, crossChainTradeData.tradeTimeout);
+				long p2shFee = bitcoiny.getP2shFee(feeTimestamp);
+				long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
 
-			switch (htlcStatusA) {
-				case UNFUNDED:
-				case FUNDING_IN_PROGRESS:
-					// Still waiting for P2SH-A to be funded...
-					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				// Create redeem script based on destination chain
+				byte[] redeemScriptA;
+				String p2shAddressA;
+				BitcoinyHTLC.Status htlcStatusA;
+				if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+					redeemScriptA = PirateChainHTLC.buildScript(tradeBotData.getTradeForeignPublicKey(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
+					p2shAddressA = PirateChain.getInstance().deriveP2shAddressBPrefix(redeemScriptA);
+					htlcStatusA = PirateChainHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+				} else {
+					redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
+					p2shAddressA = bitcoiny.deriveP2shAddress(redeemScriptA);
+					htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+				}
+				LOGGER.info(String.format("Refunding P2SH address: %s", p2shAddressA));
 
-				case REDEEM_IN_PROGRESS:
-				case REDEEMED:
-				case REFUND_IN_PROGRESS:
-				case REFUNDED:
-					// Too late!
-					return false;
+				switch (htlcStatusA) {
+					case UNFUNDED:
+					case FUNDING_IN_PROGRESS:
+						// Still waiting for P2SH-A to be funded...
+						continue;
 
-				case FUNDED:{
-					Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
-					ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-					List<TransactionOutput> fundingOutputs = bitcoiny.getUnspentOutputs(p2shAddressA);
+					case REDEEM_IN_PROGRESS:
+					case REDEEMED:
+					case REFUND_IN_PROGRESS:
+					case REFUNDED:
+						// Too late!
+						continue;
 
-					// Validate the destination foreign blockchain address
-					Address receiving = Address.fromString(bitcoiny.getNetworkParameters(), receiveAddress);
-					if (receiving.getOutputScriptType() != Script.ScriptType.P2PKH)
-						throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+					case FUNDED: {
+						Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
 
-					Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(bitcoiny.getNetworkParameters(), refundAmount, refundKey,
-							fundingOutputs, redeemScriptA, lockTime, receiving.getHash());
+						if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+							// Pirate Chain custom integration
 
-					bitcoiny.broadcastTransaction(p2shRefundTransaction);
-					return true;
+							PirateChain pirateChain = PirateChain.getInstance();
+							String p2shAddressT3 = pirateChain.deriveP2shAddress(redeemScriptA);
+
+							// Get funding txid
+							String fundingTxidHex = PirateChainHTLC.getUnspentFundingTxid(pirateChain.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+							if (fundingTxidHex == null) {
+								throw new ForeignBlockchainException("Missing funding txid when refunding P2SH");
+							}
+							String fundingTxid58 = Base58.encode(HashCode.fromString(fundingTxidHex).asBytes());
+
+							byte[] privateKey = tradeBotData.getTradePrivateKey();
+							String privateKey58 = Base58.encode(privateKey);
+							String redeemScript58 = Base58.encode(redeemScriptA);
+
+							String txid = PirateChain.getInstance().refundP2sh(p2shAddressT3,
+									receiveAddress, refundAmount.value, redeemScript58, fundingTxid58, lockTime, privateKey58);
+							LOGGER.info("Refund txid: {}", txid);
+						} else {
+							// ElectrumX coins
+
+							ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
+							List<TransactionOutput> fundingOutputs = bitcoiny.getUnspentOutputs(p2shAddressA);
+
+							// Validate the destination foreign blockchain address
+							Address receiving = Address.fromString(bitcoiny.getNetworkParameters(), receiveAddress);
+							if (receiving.getOutputScriptType() != Script.ScriptType.P2PKH)
+								throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+							Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(bitcoiny.getNetworkParameters(), refundAmount, refundKey,
+									fundingOutputs, redeemScriptA, lockTime, receiving.getHash());
+
+							bitcoiny.broadcastTransaction(p2shRefundTransaction);
+						}
+
+						return true;
+					}
 				}
 			}
 

src/main/java/org/qortal/api/websocket/ChatMessagesWebSocket.java

@@ -46,6 +46,9 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 						null,
 						txGroupId,
 						null,
+						null,
+						null,
+						null,
 						null, null, null);
 
 				sendMessages(session, chatMessages);
@@ -69,6 +72,9 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			List<ChatMessage> chatMessages = repository.getChatRepository().getMessagesMatchingCriteria(
+					null,
+					null,
+					null,
 					null,
 					null,
 					null,

src/main/java/org/qortal/api/websocket/TradeBotWebSocket.java

@@ -2,10 +2,7 @@ package org.qortal.api.websocket;
 
 import java.io.IOException;
 import java.io.StringWriter;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 import java.util.stream.Collectors;
 
 import org.eclipse.jetty.websocket.api.Session;
@@ -85,6 +82,7 @@ public class TradeBotWebSocket extends ApiWebSocket implements Listener {
 	@Override
 	public void onWebSocketConnect(Session session) {
 		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		final boolean excludeInitialData = queryParams.get("excludeInitialData") != null;
 
 		List<String> foreignBlockchains = queryParams.get("foreignBlockchain");
 		final String foreignBlockchain = foreignBlockchains == null ? null : foreignBlockchains.get(0);
@@ -98,15 +96,22 @@ public class TradeBotWebSocket extends ApiWebSocket implements Listener {
 		// save session's preferred blockchain (if any)
 		sessionBlockchain.put(session, foreignBlockchain);
 
-		// Send all known trade-bot entries
-		try (final Repository repository = RepositoryManager.getRepository()) {
-			List<TradeBotData> tradeBotEntries = repository.getCrossChainRepository().getAllTradeBotData();
 
-			// Optional filtering
-			if (foreignBlockchain != null)
-				tradeBotEntries = tradeBotEntries.stream()
-						.filter(tradeBotData -> tradeBotData.getForeignBlockchain().equals(foreignBlockchain))
-						.collect(Collectors.toList());
+
+		// Maybe send all known trade-bot entries
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			List<TradeBotData> tradeBotEntries = new ArrayList<>();
+
+			// We might need to exclude the initial data from the response
+			if (!excludeInitialData) {
+				tradeBotEntries = repository.getCrossChainRepository().getAllTradeBotData();
+
+				// Optional filtering
+				if (foreignBlockchain != null)
+					tradeBotEntries = tradeBotEntries.stream()
+							.filter(tradeBotData -> tradeBotData.getForeignBlockchain().equals(foreignBlockchain))
+							.collect(Collectors.toList());
+			}
 
 			if (!sendEntries(session, tradeBotEntries)) {
 				session.close(4002, "websocket issue");

src/main/java/org/qortal/api/websocket/TradeOffersWebSocket.java

@@ -173,6 +173,7 @@ public class TradeOffersWebSocket extends ApiWebSocket implements Listener {
 	public void onWebSocketConnect(Session session) {
 		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
 		final boolean includeHistoric = queryParams.get("includeHistoric") != null;
+		final boolean excludeInitialData = queryParams.get("excludeInitialData") != null;
 
 		List<String> foreignBlockchains = queryParams.get("foreignBlockchain");
 		final String foreignBlockchain = foreignBlockchains == null ? null : foreignBlockchains.get(0);
@@ -189,20 +190,23 @@ public class TradeOffersWebSocket extends ApiWebSocket implements Listener {
 
 		List<CrossChainOfferSummary> crossChainOfferSummaries = new ArrayList<>();
 
-		synchronized (cachedInfoByBlockchain) {
-			Collection<CachedOfferInfo> cachedInfos;
+		// We might need to exclude the initial data from the response
+		if (!excludeInitialData) {
+			synchronized (cachedInfoByBlockchain) {
+				Collection<CachedOfferInfo> cachedInfos;
 
-			if (foreignBlockchain == null)
-				// No preferred blockchain, so iterate through all of them
-				cachedInfos = cachedInfoByBlockchain.values();
-			else
-				cachedInfos = Collections.singleton(cachedInfoByBlockchain.computeIfAbsent(foreignBlockchain, k -> new CachedOfferInfo()));
+				if (foreignBlockchain == null)
+					// No preferred blockchain, so iterate through all of them
+					cachedInfos = cachedInfoByBlockchain.values();
+				else
+					cachedInfos = Collections.singleton(cachedInfoByBlockchain.computeIfAbsent(foreignBlockchain, k -> new CachedOfferInfo()));
 
-			for (CachedOfferInfo cachedInfo : cachedInfos) {
-				crossChainOfferSummaries.addAll(cachedInfo.currentSummaries.values());
+				for (CachedOfferInfo cachedInfo : cachedInfos) {
+					crossChainOfferSummaries.addAll(cachedInfo.currentSummaries.values());
 
-				if (includeHistoric)
-					crossChainOfferSummaries.addAll(cachedInfo.historicSummaries.values());
+					if (includeHistoric)
+						crossChainOfferSummaries.addAll(cachedInfo.historicSummaries.values());
+				}
 			}
 		}
 

src/main/java/org/qortal/api/websocket/TradePresenceWebSocket.java

@@ -65,11 +65,15 @@ public class TradePresenceWebSocket extends ApiWebSocket implements Listener {
 	@Override
 	public void onWebSocketConnect(Session session) {
 		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		final boolean excludeInitialData = queryParams.get("excludeInitialData") != null;
 
-		List<TradePresenceData> tradePresences;
+		List<TradePresenceData> tradePresences = new ArrayList<>();
 
-		synchronized (currentEntries) {
-			tradePresences = List.copyOf(currentEntries.values());
+		// We might need to exclude the initial data from the response
+		if (!excludeInitialData) {
+			synchronized (currentEntries) {
+				tradePresences = List.copyOf(currentEntries.values());
+			}
 		}
 
 		if (!sendTradePresences(session, tradePresences)) {

src/main/java/org/qortal/arbitrary/ArbitraryDataBuilder.java

@@ -2,6 +2,7 @@ package org.qortal.arbitrary;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.arbitrary.metadata.ArbitraryDataMetadataCache;
 import org.qortal.arbitrary.misc.Service;
@@ -88,7 +89,7 @@ public class ArbitraryDataBuilder {
             if (latestPut == null) {
                 String message = String.format("Couldn't find PUT transaction for name %s, service %s and identifier %s",
                         this.name, this.service, this.identifierString());
-                throw new DataException(message);
+                throw new DataNotPublishedException(message);
             }
             this.latestPutTransaction = latestPut;
 

src/main/java/org/qortal/arbitrary/ArbitraryDataReader.java

@@ -4,6 +4,7 @@ import org.apache.commons.io.FileUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.arbitrary.ArbitraryDataBuildManager;
@@ -169,10 +170,18 @@ public class ArbitraryDataReader {
             this.uncompress();
             this.validate();
 
+        } catch (DataNotPublishedException e) {
+            if (e.getMessage() != null) {
+                // Log the message only, to avoid spamming the logs with a full stack trace
+                LOGGER.debug("DataNotPublishedException when trying to load QDN resource: {}", e.getMessage());
+            }
+            this.deleteWorkingDirectory();
+            throw e;
+
         } catch (DataException e) {
             LOGGER.info("DataException when trying to load QDN resource", e);
             this.deleteWorkingDirectory();
-            throw new DataException(e.getMessage());
+            throw e;
 
         } finally {
             this.postExecute();

src/main/java/org/qortal/arbitrary/ArbitraryDataResource.java

@@ -3,6 +3,7 @@ package org.qortal.arbitrary;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.arbitrary.ArbitraryDataFile.ResourceIdType;
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.arbitrary.ArbitraryDataBuildManager;
@@ -325,7 +326,7 @@ public class ArbitraryDataResource {
             if (latestPut == null) {
                 String message = String.format("Couldn't find PUT transaction for name %s, service %s and identifier %s",
                         this.resourceId, this.service, this.identifierString());
-                throw new DataException(message);
+                throw new DataNotPublishedException(message);
             }
             this.latestPutTransaction = latestPut;
 

src/main/java/org/qortal/arbitrary/exception/DataNotPublishedException.java

@@ -0,0 +1,22 @@
+package org.qortal.arbitrary.exception;
+
+import org.qortal.repository.DataException;
+
+public class DataNotPublishedException extends DataException {
+
+	public DataNotPublishedException() {
+	}
+
+	public DataNotPublishedException(String message) {
+		super(message);
+	}
+
+	public DataNotPublishedException(String message, Throwable cause) {
+		super(message, cause);
+	}
+
+	public DataNotPublishedException(Throwable cause) {
+		super(cause);
+	}
+
+}

src/main/java/org/qortal/arbitrary/misc/Service.java

@@ -1,16 +1,16 @@
 package org.qortal.arbitrary.misc;
 
+import org.apache.commons.io.FilenameUtils;
 import org.json.JSONObject;
 import org.qortal.arbitrary.ArbitraryDataRenderer;
 import org.qortal.transaction.Transaction;
 import org.qortal.utils.FilesystemUtils;
 
+import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.util.Arrays;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 import static java.util.Arrays.stream;
 import static java.util.stream.Collectors.toMap;
@@ -18,6 +18,31 @@ import static java.util.stream.Collectors.toMap;
 public enum Service {
     AUTO_UPDATE(1, false, null, null),
     ARBITRARY_DATA(100, false, null, null),
+    QCHAT_ATTACHMENT(120, true, 1024*1024L, null) {
+        @Override
+        public ValidationResult validate(Path path) {
+            // Custom validation function to require a single file, with a whitelisted extension
+            int fileCount = 0;
+            File[] files = path.toFile().listFiles();
+            if (files != null) {
+                for (File file : files) {
+                    if (file.isDirectory()) {
+                        return ValidationResult.DIRECTORIES_NOT_ALLOWED;
+                    }
+                    final String extension = FilenameUtils.getExtension(file.getName()).toLowerCase();
+                    final List<String> allowedExtensions = Arrays.asList("zip", "pdf", "txt", "odt", "ods", "doc", "docx", "xls", "xlsx", "ppt", "pptx");
+                    if (extension == null || !allowedExtensions.contains(extension)) {
+                        return ValidationResult.INVALID_FILE_EXTENSION;
+                    }
+                    fileCount++;
+                }
+            }
+            if (fileCount != 1) {
+                return ValidationResult.INVALID_FILE_COUNT;
+            }
+            return ValidationResult.OK;
+        }
+    },
     WEBSITE(200, true, null, null) {
         @Override
         public ValidationResult validate(Path path) {
@@ -38,6 +63,7 @@ public enum Service {
     GIT_REPOSITORY(300, false, null, null),
     IMAGE(400, true, 10*1024*1024L, null),
     THUMBNAIL(410, true, 500*1024L, null),
+    QCHAT_IMAGE(420, true, 500*1024L, null),
     VIDEO(500, false, null, null),
     AUDIO(600, false, null, null),
     BLOG(700, false, null, null),
@@ -48,7 +74,30 @@ public enum Service {
     PLAYLIST(910, true, null, null),
     APP(1000, false, null, null),
     METADATA(1100, false, null, null),
-    QORTAL_METADATA(1111, true, 10*1024L, Arrays.asList("title", "description", "tags"));
+    GIF_REPOSITORY(1200, true, 25*1024*1024L, null) {
+        @Override
+        public ValidationResult validate(Path path) {
+            // Custom validation function to require .gif files only, and at least 1
+            int gifCount = 0;
+            File[] files = path.toFile().listFiles();
+            if (files != null) {
+                for (File file : files) {
+                    if (file.isDirectory()) {
+                        return ValidationResult.DIRECTORIES_NOT_ALLOWED;
+                    }
+                    String extension = FilenameUtils.getExtension(file.getName()).toLowerCase();
+                    if (!Objects.equals(extension, "gif")) {
+                        return ValidationResult.INVALID_FILE_EXTENSION;
+                    }
+                    gifCount++;
+                }
+            }
+            if (gifCount == 0) {
+                return ValidationResult.MISSING_DATA;
+            }
+            return ValidationResult.OK;
+        }
+    };
 
     public final int value;
     private final boolean requiresValidation;
@@ -114,7 +163,11 @@ public enum Service {
         OK(1),
         MISSING_KEYS(2),
         EXCEEDS_SIZE_LIMIT(3),
-        MISSING_INDEX_FILE(4);
+        MISSING_INDEX_FILE(4),
+        DIRECTORIES_NOT_ALLOWED(5),
+        INVALID_FILE_EXTENSION(6),
+        MISSING_DATA(7),
+        INVALID_FILE_COUNT(8);
 
         public final int value;
 

src/main/java/org/qortal/block/Block.java

@@ -89,7 +89,8 @@ public class Block {
 		ONLINE_ACCOUNT_UNKNOWN(71),
 		ONLINE_ACCOUNT_SIGNATURES_MISSING(72),
 		ONLINE_ACCOUNT_SIGNATURES_MALFORMED(73),
-		ONLINE_ACCOUNT_SIGNATURE_INCORRECT(74);
+		ONLINE_ACCOUNT_SIGNATURE_INCORRECT(74),
+		ONLINE_ACCOUNT_NONCE_INCORRECT(75);
 
 		public final int value;
 
@@ -135,7 +136,7 @@ public class Block {
 	}
 
 	/** Lazy-instantiated expanded info on block's online accounts. */
-	private static class ExpandedAccount {
+	public static class ExpandedAccount {
 		private final RewardShareData rewardShareData;
 		private final int sharePercent;
 		private final boolean isRecipientAlsoMinter;
@@ -168,6 +169,13 @@ public class Block {
 			}
 		}
 
+		public Account getMintingAccount() {
+			return this.mintingAccount;
+		}
+		public Account getRecipientAccount() {
+			return this.recipientAccount;
+		}
+
 		/**
 		 * Returns share bin for expanded account.
 		 * <p>
@@ -362,13 +370,28 @@ public class Block {
 			return null;
 		}
 
+		int height = parentBlockData.getHeight() + 1;
 		long timestamp = calcTimestamp(parentBlockData, minter.getPublicKey(), minterLevel);
 		long onlineAccountsTimestamp = OnlineAccountsManager.getCurrentOnlineAccountTimestamp();
 
-		// Fetch our list of online accounts
+		// Fetch our list of online accounts, removing any that are missing a nonce
 		List<OnlineAccountData> onlineAccounts = OnlineAccountsManager.getInstance().getOnlineAccounts(onlineAccountsTimestamp);
+		onlineAccounts.removeIf(a -> a.getNonce() == null || a.getNonce() < 0);
+
+		// After feature trigger, remove any online accounts that are level 0
+		if (height >= BlockChain.getInstance().getOnlineAccountMinterLevelValidationHeight()) {
+			onlineAccounts.removeIf(a -> {
+				try {
+					return Account.getRewardShareEffectiveMintingLevel(repository, a.getPublicKey()) == 0;
+				} catch (DataException e) {
+					// Something went wrong, so remove the account
+					return true;
+				}
+			});
+		}
+
 		if (onlineAccounts.isEmpty()) {
-			LOGGER.error("No online accounts - not even our own?");
+			LOGGER.debug("No online accounts - not even our own?");
 			return null;
 		}
 
@@ -396,24 +419,36 @@ public class Block {
 		byte[] encodedOnlineAccounts = BlockTransformer.encodeOnlineAccounts(onlineAccountsSet);
 		int onlineAccountsCount = onlineAccountsSet.size();
 
-		byte[] onlineAccountsSignatures;
-		if (timestamp >= BlockChain.getInstance().getAggregateSignatureTimestamp()) {
-			// Collate all signatures
-			Collection<byte[]> signaturesToAggregate = indexedOnlineAccounts.values()
-					.stream()
-					.map(OnlineAccountData::getSignature)
-					.collect(Collectors.toList());
+		// Collate all signatures
+		Collection<byte[]> signaturesToAggregate = indexedOnlineAccounts.values()
+				.stream()
+				.map(OnlineAccountData::getSignature)
+				.collect(Collectors.toList());
 
-			// Aggregated, single signature
-			onlineAccountsSignatures = Qortal25519Extras.aggregateSignatures(signaturesToAggregate);
-		} else {
-			// Concatenate online account timestamp signatures (in correct order)
-			onlineAccountsSignatures = new byte[onlineAccountsCount * Transformer.SIGNATURE_LENGTH];
+		// Aggregated, single signature
+		byte[] onlineAccountsSignatures = Qortal25519Extras.aggregateSignatures(signaturesToAggregate);
+
+		// Add nonces to the end of the online accounts signatures
+		try {
+			// Create ordered list of nonce values
+			List<Integer> nonces = new ArrayList<>();
 			for (int i = 0; i < onlineAccountsCount; ++i) {
 				Integer accountIndex = accountIndexes.get(i);
 				OnlineAccountData onlineAccountData = indexedOnlineAccounts.get(accountIndex);
-				System.arraycopy(onlineAccountData.getSignature(), 0, onlineAccountsSignatures, i * Transformer.SIGNATURE_LENGTH, Transformer.SIGNATURE_LENGTH);
+				nonces.add(onlineAccountData.getNonce());
 			}
+
+			// Encode the nonces to a byte array
+			byte[] encodedNonces = BlockTransformer.encodeOnlineAccountNonces(nonces);
+
+			// Append the encoded nonces to the encoded online account signatures
+			ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+			outputStream.write(onlineAccountsSignatures);
+			outputStream.write(encodedNonces);
+			onlineAccountsSignatures = outputStream.toByteArray();
+		}
+		catch (TransformationException | IOException e) {
+			return null;
 		}
 
 		byte[] minterSignature = minter.sign(BlockTransformer.getBytesForMinterSignature(parentBlockData,
@@ -421,7 +456,6 @@ public class Block {
 
 		int transactionCount = 0;
 		byte[] transactionsSignature = null;
-		int height = parentBlockData.getHeight() + 1;
 
 		int atCount = 0;
 		long atFees = 0;
@@ -1015,6 +1049,15 @@ public class Block {
 		if (onlineRewardShares == null)
 			return ValidationResult.ONLINE_ACCOUNT_UNKNOWN;
 
+		// After feature trigger, require all online account minters to be greater than level 0
+		if (this.getBlockData().getHeight() >= BlockChain.getInstance().getOnlineAccountMinterLevelValidationHeight()) {
+			List<ExpandedAccount> expandedAccounts = this.getExpandedAccounts();
+			for (ExpandedAccount account : expandedAccounts) {
+				if (account.getMintingAccount().getEffectiveMintingLevel() == 0)
+					return ValidationResult.ONLINE_ACCOUNTS_INVALID;
+			}
+		}
+
 		// If block is past a certain age then we simply assume the signatures were correct
 		long signatureRequirementThreshold = NTP.getTime() - BlockChain.getInstance().getOnlineAccountSignaturesMinLifetime();
 		if (this.blockData.getTimestamp() < signatureRequirementThreshold)
@@ -1023,58 +1066,63 @@ public class Block {
 		if (this.blockData.getOnlineAccountsSignatures() == null || this.blockData.getOnlineAccountsSignatures().length == 0)
 			return ValidationResult.ONLINE_ACCOUNT_SIGNATURES_MISSING;
 
-		if (this.blockData.getTimestamp() >= BlockChain.getInstance().getAggregateSignatureTimestamp()) {
-			// We expect just the one, aggregated signature
-			if (this.blockData.getOnlineAccountsSignatures().length != Transformer.SIGNATURE_LENGTH)
-				return ValidationResult.ONLINE_ACCOUNT_SIGNATURES_MALFORMED;
-		} else {
-			if (this.blockData.getOnlineAccountsSignatures().length != onlineRewardShares.size() * Transformer.SIGNATURE_LENGTH)
-				return ValidationResult.ONLINE_ACCOUNT_SIGNATURES_MALFORMED;
-		}
+		final int signaturesLength = Transformer.SIGNATURE_LENGTH;
+		final int noncesLength = onlineRewardShares.size() * Transformer.INT_LENGTH;
+
+		// We expect nonces to be appended to the online accounts signatures
+		if (this.blockData.getOnlineAccountsSignatures().length != signaturesLength + noncesLength)
+			return ValidationResult.ONLINE_ACCOUNT_SIGNATURES_MALFORMED;
 
 		// Check signatures
 		long onlineTimestamp = this.blockData.getOnlineAccountsTimestamp();
 		byte[] onlineTimestampBytes = Longs.toByteArray(onlineTimestamp);
 
-		// Extract online accounts' timestamp signatures from block data. Only one signature if aggregated.
-		List<byte[]> onlineAccountsSignatures = BlockTransformer.decodeTimestampSignatures(this.blockData.getOnlineAccountsSignatures());
+		byte[] encodedOnlineAccountSignatures = this.blockData.getOnlineAccountsSignatures();
 
-		if (this.blockData.getTimestamp() >= BlockChain.getInstance().getAggregateSignatureTimestamp()) {
-			// Aggregate all public keys
-			Collection<byte[]> publicKeys = onlineRewardShares.stream()
-					.map(RewardShareData::getRewardSharePublicKey)
-					.collect(Collectors.toList());
+		// Split online account signatures into signature(s) + nonces, then validate the nonces
+		byte[] extractedSignatures = BlockTransformer.extract(encodedOnlineAccountSignatures, 0, signaturesLength);
+		byte[] extractedNonces = BlockTransformer.extract(encodedOnlineAccountSignatures, signaturesLength, onlineRewardShares.size() * Transformer.INT_LENGTH);
+		encodedOnlineAccountSignatures = extractedSignatures;
 
-			byte[] aggregatePublicKey = Qortal25519Extras.aggregatePublicKeys(publicKeys);
+		List<Integer> nonces = BlockTransformer.decodeOnlineAccountNonces(extractedNonces);
 
-			byte[] aggregateSignature = onlineAccountsSignatures.get(0);
+		// Build block's view of online accounts (without signatures, as we don't need them here)
+		Set<OnlineAccountData> onlineAccounts = new HashSet<>();
+		for (int i = 0; i < onlineRewardShares.size(); ++i) {
+			Integer nonce = nonces.get(i);
+			byte[] publicKey = onlineRewardShares.get(i).getRewardSharePublicKey();
 
-			// One-step verification of aggregate signature using aggregate public key
-			if (!Qortal25519Extras.verifyAggregated(aggregatePublicKey, aggregateSignature, onlineTimestampBytes))
-				return ValidationResult.ONLINE_ACCOUNT_SIGNATURE_INCORRECT;
-		} else {
-			// Build block's view of online accounts
-			Set<OnlineAccountData> onlineAccounts = new HashSet<>();
-			for (int i = 0; i < onlineAccountsSignatures.size(); ++i) {
-				byte[] signature = onlineAccountsSignatures.get(i);
-				byte[] publicKey = onlineRewardShares.get(i).getRewardSharePublicKey();
-
-				OnlineAccountData onlineAccountData = new OnlineAccountData(onlineTimestamp, signature, publicKey);
-				onlineAccounts.add(onlineAccountData);
-			}
-
-			// Remove those already validated & cached by online accounts manager - no need to re-validate them
-			OnlineAccountsManager.getInstance().removeKnown(onlineAccounts, onlineTimestamp);
-
-			// Validate the rest
-			for (OnlineAccountData onlineAccount : onlineAccounts)
-				if (!Crypto.verify(onlineAccount.getPublicKey(), onlineAccount.getSignature(), onlineTimestampBytes))
-					return ValidationResult.ONLINE_ACCOUNT_SIGNATURE_INCORRECT;
-
-			// We've validated these, so allow online accounts manager to cache
-			OnlineAccountsManager.getInstance().addBlocksOnlineAccounts(onlineAccounts, onlineTimestamp);
+			OnlineAccountData onlineAccountData = new OnlineAccountData(onlineTimestamp, null, publicKey, nonce);
+			onlineAccounts.add(onlineAccountData);
 		}
 
+		// Remove those already validated & cached by online accounts manager - no need to re-validate them
+		OnlineAccountsManager.getInstance().removeKnown(onlineAccounts, onlineTimestamp);
+
+		// Validate the rest
+		for (OnlineAccountData onlineAccount : onlineAccounts)
+			if (!OnlineAccountsManager.getInstance().verifyMemoryPoW(onlineAccount, null))
+				return ValidationResult.ONLINE_ACCOUNT_NONCE_INCORRECT;
+
+		// Cache the valid online accounts as they will likely be needed for the next block
+		OnlineAccountsManager.getInstance().addBlocksOnlineAccounts(onlineAccounts, onlineTimestamp);
+
+		// Extract online accounts' timestamp signatures from block data. Only one signature if aggregated.
+		List<byte[]> onlineAccountsSignatures = BlockTransformer.decodeTimestampSignatures(encodedOnlineAccountSignatures);
+
+		// Aggregate all public keys
+		Collection<byte[]> publicKeys = onlineRewardShares.stream()
+				.map(RewardShareData::getRewardSharePublicKey)
+				.collect(Collectors.toList());
+
+		byte[] aggregatePublicKey = Qortal25519Extras.aggregatePublicKeys(publicKeys);
+
+		byte[] aggregateSignature = onlineAccountsSignatures.get(0);
+
+		// One-step verification of aggregate signature using aggregate public key
+		if (!Qortal25519Extras.verifyAggregated(aggregatePublicKey, aggregateSignature, onlineTimestampBytes))
+			return ValidationResult.ONLINE_ACCOUNT_SIGNATURE_INCORRECT;
+
 		// All online accounts valid, so save our list of online accounts for potential later use
 		this.cachedOnlineRewardShares = onlineRewardShares;
 
@@ -1415,6 +1463,9 @@ public class Block {
 			if (this.blockData.getHeight() == 212937)
 				// Apply fix for block 212937
 				Block212937.processFix(this);
+
+			else if (this.blockData.getHeight() == BlockChain.getInstance().getSelfSponsorshipAlgoV1Height())
+				SelfSponsorshipAlgoV1Block.processAccountPenalties(this);
 		}
 
 		// We're about to (test-)process a batch of transactions,
@@ -1471,19 +1522,23 @@ public class Block {
 		// Batch update in repository
 		repository.getAccountRepository().modifyMintedBlockCounts(allUniqueExpandedAccounts.stream().map(AccountData::getAddress).collect(Collectors.toList()), +1);
 
+		// Keep track of level bumps in case we need to apply to other entries
+		Map<String, Integer> bumpedAccounts = new HashMap<>();
+
 		// Local changes and also checks for level bump
 		for (AccountData accountData : allUniqueExpandedAccounts) {
 			// Adjust count locally (in Java)
 			accountData.setBlocksMinted(accountData.getBlocksMinted() + 1);
 			LOGGER.trace(() -> String.format("Block minter %s up to %d minted block%s", accountData.getAddress(), accountData.getBlocksMinted(), (accountData.getBlocksMinted() != 1 ? "s" : "")));
 
-			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment();
+			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment() + accountData.getBlocksMintedPenalty();
 
 			for (int newLevel = maximumLevel; newLevel >= 0; --newLevel)
 				if (effectiveBlocksMinted >= cumulativeBlocksByLevel.get(newLevel)) {
 					if (newLevel > accountData.getLevel()) {
 						// Account has increased in level!
 						accountData.setLevel(newLevel);
+						bumpedAccounts.put(accountData.getAddress(), newLevel);
 						repository.getAccountRepository().setLevel(accountData);
 						LOGGER.trace(() -> String.format("Block minter %s bumped to level %d", accountData.getAddress(), accountData.getLevel()));
 					}
@@ -1491,6 +1546,25 @@ public class Block {
 					break;
 				}
 		}
+
+		// Also bump other entries if need be
+		if (!bumpedAccounts.isEmpty()) {
+			for (ExpandedAccount expandedAccount : expandedAccounts) {
+				Integer newLevel = bumpedAccounts.get(expandedAccount.mintingAccountData.getAddress());
+				if (newLevel != null && expandedAccount.mintingAccountData.getLevel() != newLevel) {
+					expandedAccount.mintingAccountData.setLevel(newLevel);
+					LOGGER.trace("Also bumped {} to level {}", expandedAccount.mintingAccountData.getAddress(), newLevel);
+				}
+
+				if (!expandedAccount.isRecipientAlsoMinter) {
+					newLevel = bumpedAccounts.get(expandedAccount.recipientAccountData.getAddress());
+					if (newLevel != null && expandedAccount.recipientAccountData.getLevel() != newLevel) {
+						expandedAccount.recipientAccountData.setLevel(newLevel);
+						LOGGER.trace("Also bumped {} to level {}", expandedAccount.recipientAccountData.getAddress(), newLevel);
+					}
+				}
+			}
+		}
 	}
 
 	protected void processBlockRewards() throws DataException {
@@ -1650,6 +1724,9 @@ public class Block {
 				// Revert fix for block 212937
 				Block212937.orphanFix(this);
 
+			else if (this.blockData.getHeight() == BlockChain.getInstance().getSelfSponsorshipAlgoV1Height())
+				SelfSponsorshipAlgoV1Block.orphanAccountPenalties(this);
+
 			// Block rewards, including transaction fees, removed after transactions undone
 			orphanBlockRewards();
 
@@ -1778,7 +1855,7 @@ public class Block {
 			accountData.setBlocksMinted(accountData.getBlocksMinted() - 1);
 			LOGGER.trace(() -> String.format("Block minter %s down to %d minted block%s", accountData.getAddress(), accountData.getBlocksMinted(), (accountData.getBlocksMinted() != 1 ? "s" : "")));
 
-			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment();
+			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment() + accountData.getBlocksMintedPenalty();
 
 			for (int newLevel = maximumLevel; newLevel >= 0; --newLevel)
 				if (effectiveBlocksMinted >= cumulativeBlocksByLevel.get(newLevel)) {

src/main/java/org/qortal/block/BlockChain.java

@@ -74,7 +74,11 @@ public class BlockChain {
 		transactionV5Timestamp,
 		transactionV6Timestamp,
 		disableReferenceTimestamp,
-		aggregateSignatureTimestamp;
+		increaseOnlineAccountsDifficultyTimestamp,
+		onlineAccountMinterLevelValidationHeight,
+		selfSponsorshipAlgoV1Height,
+		feeValidationFixTimestamp,
+		chatReferenceTimestamp;
 	}
 
 	// Custom transaction fees
@@ -96,6 +100,13 @@ public class BlockChain {
 	/** Whether only one registered name is allowed per account. */
 	private boolean oneNamePerAccount = false;
 
+	/** Checkpoints */
+	public static class Checkpoint {
+		public int height;
+		public String signature;
+	}
+	private List<Checkpoint> checkpoints;
+
 	/** Block rewards by block height */
 	public static class RewardByHeight {
 		public int height;
@@ -196,6 +207,9 @@ public class BlockChain {
 	 * featureTriggers because unit tests need to set this value via Reflection. */
 	private long onlineAccountsModulusV2Timestamp;
 
+	/** Snapshot timestamp for self sponsorship algo V1 */
+	private long selfSponsorshipAlgoV1SnapshotTimestamp;
+
 	/** Max reward shares by block height */
 	public static class MaxRewardSharesByTimestamp {
 		public long timestamp;
@@ -356,6 +370,11 @@ public class BlockChain {
 		return this.onlineAccountsModulusV2Timestamp;
 	}
 
+	// Self sponsorship algo
+	public long getSelfSponsorshipAlgoV1SnapshotTimestamp() {
+		return this.selfSponsorshipAlgoV1SnapshotTimestamp;
+	}
+
 	/** Returns true if approval-needing transaction types require a txGroupId other than NO_GROUP. */
 	public boolean getRequireGroupForApproval() {
 		return this.requireGroupForApproval;
@@ -369,6 +388,10 @@ public class BlockChain {
 		return this.oneNamePerAccount;
 	}
 
+	public List<Checkpoint> getCheckpoints() {
+		return this.checkpoints;
+	}
+
 	public List<RewardByHeight> getBlockRewardsByHeight() {
 		return this.rewardsByHeight;
 	}
@@ -479,10 +502,27 @@ public class BlockChain {
 		return this.featureTriggers.get(FeatureTrigger.disableReferenceTimestamp.name()).longValue();
 	}
 
-	public long getAggregateSignatureTimestamp() {
-		return this.featureTriggers.get(FeatureTrigger.aggregateSignatureTimestamp.name()).longValue();
+	public long getIncreaseOnlineAccountsDifficultyTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.increaseOnlineAccountsDifficultyTimestamp.name()).longValue();
 	}
 
+	public int getSelfSponsorshipAlgoV1Height() {
+		return this.featureTriggers.get(FeatureTrigger.selfSponsorshipAlgoV1Height.name()).intValue();
+	}
+
+	public long getOnlineAccountMinterLevelValidationHeight() {
+		return this.featureTriggers.get(FeatureTrigger.onlineAccountMinterLevelValidationHeight.name()).intValue();
+	}
+
+	public long getFeeValidationFixTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.feeValidationFixTimestamp.name()).longValue();
+	}
+
+	public long getChatReferenceTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.chatReferenceTimestamp.name()).longValue();
+	}
+
+
 	// More complex getters for aspects that change by height or timestamp
 
 	public long getRewardAtHeight(int ourHeight) {
@@ -650,6 +690,7 @@ public class BlockChain {
 
 		boolean isTopOnly = Settings.getInstance().isTopOnly();
 		boolean archiveEnabled = Settings.getInstance().isArchiveEnabled();
+		boolean isLite = Settings.getInstance().isLite();
 		boolean canBootstrap = Settings.getInstance().getBootstrap();
 		boolean needsArchiveRebuild = false;
 		BlockData chainTip;
@@ -670,22 +711,44 @@ public class BlockChain {
 					}
 				}
 			}
+
+			// Validate checkpoints
+			// Limited to topOnly nodes for now, in order to reduce risk, and to solve a real-world problem with divergent topOnly nodes
+			// TODO: remove the isTopOnly conditional below once this feature has had more testing time
+			if (isTopOnly && !isLite) {
+				List<Checkpoint> checkpoints = BlockChain.getInstance().getCheckpoints();
+				for (Checkpoint checkpoint : checkpoints) {
+					BlockData blockData = repository.getBlockRepository().fromHeight(checkpoint.height);
+					if (blockData == null) {
+						// Try the archive
+						blockData = repository.getBlockArchiveRepository().fromHeight(checkpoint.height);
+					}
+					if (blockData == null) {
+						LOGGER.trace("Couldn't find block for height {}", checkpoint.height);
+						// This is likely due to the block being pruned, so is safe to ignore.
+						// Continue, as there might be other blocks we can check more definitively.
+						continue;
+					}
+
+					byte[] signature = Base58.decode(checkpoint.signature);
+					if (!Arrays.equals(signature, blockData.getSignature())) {
+						LOGGER.info("Error: block at height {} with signature {} doesn't match checkpoint sig: {}. Bootstrapping...", checkpoint.height, Base58.encode(blockData.getSignature()), checkpoint.signature);
+						needsArchiveRebuild = true;
+						break;
+					}
+					LOGGER.info("Block at height {} matches checkpoint signature", blockData.getHeight());
+				}
+			}
+
 		}
 
-		boolean hasBlocks = (chainTip != null && chainTip.getHeight() > 1);
+		// Check first block is Genesis Block
+		if (!isGenesisBlockValid() || needsArchiveRebuild) {
+			try {
+				rebuildBlockchain();
 
-		if (isTopOnly && hasBlocks) {
-			// Top-only mode is enabled and we have blocks, so it's possible that the genesis block has been pruned
-			// It's best not to validate it, and there's no real need to
-		} else {
-			// Check first block is Genesis Block
-			if (!isGenesisBlockValid() || needsArchiveRebuild) {
-				try {
-					rebuildBlockchain();
-
-				} catch (InterruptedException e) {
-					throw new DataException(String.format("Interrupted when trying to rebuild blockchain: %s", e.getMessage()));
-				}
+			} catch (InterruptedException e) {
+				throw new DataException(String.format("Interrupted when trying to rebuild blockchain: %s", e.getMessage()));
 			}
 		}
 
@@ -694,9 +757,7 @@ public class BlockChain {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			repository.checkConsistency();
 
-			// Set the number of blocks to validate based on the pruned state of the chain
-			// If pruned, subtract an extra 10 to allow room for error
-			int blocksToValidate = (isTopOnly || archiveEnabled) ? Settings.getInstance().getPruneBlockLimit() - 10 : 1440;
+			int blocksToValidate = Math.min(Settings.getInstance().getPruneBlockLimit() - 10, 1440);
 
 			int startHeight = Math.max(repository.getBlockRepository().getBlockchainHeight() - blocksToValidate, 1);
 			BlockData detachedBlockData = repository.getBlockRepository().getDetachedBlockSignature(startHeight);

src/main/java/org/qortal/block/SelfSponsorshipAlgoV1Block.java

@@ -0,0 +1,133 @@
+package org.qortal.block;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.qortal.account.SelfSponsorshipAlgoV1;
+import org.qortal.api.model.AccountPenaltyStats;
+import org.qortal.crypto.Crypto;
+import org.qortal.data.account.AccountData;
+import org.qortal.data.account.AccountPenaltyData;
+import org.qortal.repository.DataException;
+import org.qortal.repository.Repository;
+import org.qortal.utils.Base58;
+
+import java.nio.charset.StandardCharsets;
+import java.util.*;
+import java.util.stream.Collectors;
+
+/**
+ * Self Sponsorship AlgoV1 Block
+ * <p>
+ * Selected block for the initial run on the "self sponsorship detection algorithm"
+ */
+public final class SelfSponsorshipAlgoV1Block {
+
+	private static final Logger LOGGER = LogManager.getLogger(SelfSponsorshipAlgoV1Block.class);
+
+
+	private SelfSponsorshipAlgoV1Block() {
+		/* Do not instantiate */
+	}
+
+	public static void processAccountPenalties(Block block) throws DataException {
+		LOGGER.info("Running algo for block processing - this will take a while...");
+		logPenaltyStats(block.repository);
+		long startTime = System.currentTimeMillis();
+		Set<AccountPenaltyData> penalties = getAccountPenalties(block.repository, -5000000);
+		block.repository.getAccountRepository().updateBlocksMintedPenalties(penalties);
+		long totalTime = System.currentTimeMillis() - startTime;
+		String hash = getHash(penalties.stream().map(p -> p.getAddress()).collect(Collectors.toList()));
+		LOGGER.info("{} penalty addresses processed (hash: {}). Total time taken: {} seconds", penalties.size(), hash, (int)(totalTime / 1000.0f));
+		logPenaltyStats(block.repository);
+
+		int updatedCount = updateAccountLevels(block.repository, penalties);
+		LOGGER.info("Account levels updated for {} penalty addresses", updatedCount);
+	}
+
+	public static void orphanAccountPenalties(Block block) throws DataException {
+		LOGGER.info("Running algo for block orphaning - this will take a while...");
+		logPenaltyStats(block.repository);
+		long startTime = System.currentTimeMillis();
+		Set<AccountPenaltyData> penalties = getAccountPenalties(block.repository, 5000000);
+		block.repository.getAccountRepository().updateBlocksMintedPenalties(penalties);
+		long totalTime = System.currentTimeMillis() - startTime;
+		String hash = getHash(penalties.stream().map(p -> p.getAddress()).collect(Collectors.toList()));
+		LOGGER.info("{} penalty addresses orphaned (hash: {}). Total time taken: {} seconds", penalties.size(), hash, (int)(totalTime / 1000.0f));
+		logPenaltyStats(block.repository);
+
+		int updatedCount = updateAccountLevels(block.repository, penalties);
+		LOGGER.info("Account levels updated for {} penalty addresses", updatedCount);
+	}
+
+	public static Set<AccountPenaltyData> getAccountPenalties(Repository repository, int penalty) throws DataException {
+		final long snapshotTimestamp = BlockChain.getInstance().getSelfSponsorshipAlgoV1SnapshotTimestamp();
+		Set<AccountPenaltyData> penalties = new LinkedHashSet<>();
+		List<String> addresses = repository.getTransactionRepository().getConfirmedRewardShareCreatorsExcludingSelfShares();
+		for (String address : addresses) {
+			//System.out.println(String.format("address: %s", address));
+			SelfSponsorshipAlgoV1 selfSponsorshipAlgoV1 = new SelfSponsorshipAlgoV1(repository, address, snapshotTimestamp, false);
+			selfSponsorshipAlgoV1.run();
+			//System.out.println(String.format("Penalty addresses: %d", selfSponsorshipAlgoV1.getPenaltyAddresses().size()));
+
+			for (String penaltyAddress : selfSponsorshipAlgoV1.getPenaltyAddresses()) {
+				penalties.add(new AccountPenaltyData(penaltyAddress, penalty));
+			}
+		}
+		return penalties;
+	}
+
+	private static int updateAccountLevels(Repository repository, Set<AccountPenaltyData> accountPenalties) throws DataException {
+		final List<Integer> cumulativeBlocksByLevel = BlockChain.getInstance().getCumulativeBlocksByLevel();
+		final int maximumLevel = cumulativeBlocksByLevel.size() - 1;
+
+		int updatedCount = 0;
+
+		for (AccountPenaltyData penaltyData : accountPenalties) {
+			AccountData accountData = repository.getAccountRepository().getAccount(penaltyData.getAddress());
+			final int effectiveBlocksMinted = accountData.getBlocksMinted() + accountData.getBlocksMintedAdjustment() + accountData.getBlocksMintedPenalty();
+
+			// Shortcut for penalties
+			if (effectiveBlocksMinted < 0) {
+				accountData.setLevel(0);
+				repository.getAccountRepository().setLevel(accountData);
+				updatedCount++;
+				LOGGER.trace(() -> String.format("Block minter %s dropped to level %d", accountData.getAddress(), accountData.getLevel()));
+				continue;
+			}
+
+			for (int newLevel = maximumLevel; newLevel >= 0; --newLevel) {
+				if (effectiveBlocksMinted >= cumulativeBlocksByLevel.get(newLevel)) {
+					accountData.setLevel(newLevel);
+					repository.getAccountRepository().setLevel(accountData);
+					updatedCount++;
+					LOGGER.trace(() -> String.format("Block minter %s increased to level %d", accountData.getAddress(), accountData.getLevel()));
+					break;
+				}
+			}
+		}
+
+		return updatedCount;
+	}
+
+	private static void logPenaltyStats(Repository repository) {
+		try {
+			LOGGER.info(getPenaltyStats(repository));
+
+		} catch (DataException e) {}
+	}
+
+	private static AccountPenaltyStats getPenaltyStats(Repository repository) throws DataException {
+		List<AccountData> accounts = repository.getAccountRepository().getPenaltyAccounts();
+		return AccountPenaltyStats.fromAccounts(accounts);
+	}
+
+	public static String getHash(List<String> penaltyAddresses) {
+		if (penaltyAddresses == null || penaltyAddresses.isEmpty()) {
+			return null;
+		}
+		Collections.sort(penaltyAddresses);
+		return Base58.encode(Crypto.digest(StringUtils.join(penaltyAddresses).getBytes(StandardCharsets.UTF_8)));
+	}
+
+}

src/main/java/org/qortal/controller/BlockMinter.java

@@ -35,6 +35,8 @@ import org.qortal.transaction.Transaction;
 import org.qortal.utils.Base58;
 import org.qortal.utils.NTP;
 
+import static org.junit.Assert.assertNotNull;
+
 // Minting new blocks
 
 public class BlockMinter extends Thread {
@@ -61,8 +63,8 @@ public class BlockMinter extends Thread {
 	public void run() {
 		Thread.currentThread().setName("BlockMinter");
 
-		if (Settings.getInstance().isLite()) {
-			// Lite nodes do not mint
+		if (Settings.getInstance().isTopOnly() || Settings.getInstance().isLite()) {
+			// Top only and lite nodes do not sign blocks
 			return;
 		}
 		if (Settings.getInstance().getWipeUnconfirmedOnStart()) {
@@ -90,6 +92,8 @@ public class BlockMinter extends Thread {
 
 		List<Block> newBlocks = new ArrayList<>();
 
+		final boolean isSingleNodeTestnet = Settings.getInstance().isSingleNodeTestnet();
+
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			// Going to need this a lot...
 			BlockRepository blockRepository = repository.getBlockRepository();
@@ -108,8 +112,9 @@ public class BlockMinter extends Thread {
 					// Free up any repository locks
 					repository.discardChanges();
 
-					// Sleep for a while
-					Thread.sleep(1000);
+					// Sleep for a while.
+					// It's faster on single node testnets, to allow lots of blocks to be minted quickly.
+					Thread.sleep(isSingleNodeTestnet ? 50 : 1000);
 
 					isMintingPossible = false;
 
@@ -220,9 +225,10 @@ public class BlockMinter extends Thread {
 					List<PrivateKeyAccount> newBlocksMintingAccounts = mintingAccountsData.stream().map(accountData -> new PrivateKeyAccount(repository, accountData.getPrivateKey())).collect(Collectors.toList());
 
 					// We might need to sit the next block out, if one of our minting accounts signed the previous one
+					// Skip this check for single node testnets, since they definitely need to mint every block
 					byte[] previousBlockMinter = previousBlockData.getMinterPublicKey();
 					boolean mintedLastBlock = mintingAccountsData.stream().anyMatch(mintingAccount -> Arrays.equals(mintingAccount.getPublicKey(), previousBlockMinter));
-					if (mintedLastBlock) {
+					if (mintedLastBlock && !isSingleNodeTestnet) {
 						LOGGER.trace(String.format("One of our keys signed the last block, so we won't sign the next one"));
 						continue;
 					}
@@ -241,7 +247,7 @@ public class BlockMinter extends Thread {
 							Block newBlock = Block.mint(repository, previousBlockData, mintingAccount);
 							if (newBlock == null) {
 								// For some reason we can't mint right now
-								moderatedLog(() -> LOGGER.error("Couldn't build a to-be-minted block"));
+								moderatedLog(() -> LOGGER.info("Couldn't build a to-be-minted block"));
 								continue;
 							}
 
@@ -433,11 +439,9 @@ public class BlockMinter extends Thread {
 
 					if (newBlockMinted) {
 						// Broadcast our new chain to network
-						BlockData newBlockData = newBlock.getBlockData();
-
-						Network network = Network.getInstance();
-						network.broadcast(broadcastPeer -> network.buildHeightMessage(broadcastPeer, newBlockData));
+						Network.getInstance().broadcastOurChain();
 					}
+
 				} catch (InterruptedException e) {
 					// We've been interrupted - time to exit
 					return;
@@ -506,6 +510,21 @@ public class BlockMinter extends Thread {
 
 		PrivateKeyAccount mintingAccount = mintingAndOnlineAccounts[0];
 
+		Block block = mintTestingBlockRetainingTimestamps(repository, mintingAccount);
+		assertNotNull("Minted block must not be null", block);
+
+		return block;
+	}
+
+	public static Block mintTestingBlockUnvalidated(Repository repository, PrivateKeyAccount... mintingAndOnlineAccounts) throws DataException {
+		if (!BlockChain.getInstance().isTestChain())
+			throw new DataException("Ignoring attempt to mint testing block for non-test chain!");
+
+		// Ensure mintingAccount is 'online' so blocks can be minted
+		OnlineAccountsManager.getInstance().ensureTestingAccountsOnline(mintingAndOnlineAccounts);
+
+		PrivateKeyAccount mintingAccount = mintingAndOnlineAccounts[0];
+
 		return mintTestingBlockRetainingTimestamps(repository, mintingAccount);
 	}
 
@@ -513,6 +532,8 @@ public class BlockMinter extends Thread {
 		BlockData previousBlockData = repository.getBlockRepository().getLastBlock();
 
 		Block newBlock = Block.mint(repository, previousBlockData, mintingAccount);
+		if (newBlock == null)
+			return null;
 
 		// Make sure we're the only thread modifying the blockchain
 		ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();

src/main/java/org/qortal/controller/Controller.java

@@ -29,6 +29,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.bouncycastle.jce.provider.BouncyCastleProvider;
 import org.bouncycastle.jsse.provider.BouncyCastleJsseProvider;
+import org.qortal.account.Account;
 import org.qortal.api.ApiService;
 import org.qortal.api.DomainMapService;
 import org.qortal.api.GatewayService;
@@ -45,7 +46,6 @@ import org.qortal.data.account.AccountData;
 import org.qortal.data.block.BlockData;
 import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.naming.NameData;
-import org.qortal.data.network.PeerChainTipData;
 import org.qortal.data.network.PeerData;
 import org.qortal.data.transaction.ChatTransactionData;
 import org.qortal.data.transaction.TransactionData;
@@ -317,6 +317,10 @@ public class Controller extends Thread {
 		}
 	}
 
+	public static long uptime() {
+		return System.currentTimeMillis() - Controller.startTime;
+	}
+
 	/** Returns highest block, or null if it's not available. */
 	public BlockData getChainTip() {
 		synchronized (this.latestBlocks) {
@@ -727,25 +731,25 @@ public class Controller extends Thread {
 
 	public static final Predicate<Peer> hasNoRecentBlock = peer -> {
 		final Long minLatestBlockTimestamp = getMinimumLatestBlockTimestamp();
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
-		return peerChainTipData == null || peerChainTipData.getLastBlockTimestamp() == null || peerChainTipData.getLastBlockTimestamp() < minLatestBlockTimestamp;
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
+		return peerChainTipData == null || peerChainTipData.getTimestamp() == null || peerChainTipData.getTimestamp() < minLatestBlockTimestamp;
 	};
 
 	public static final Predicate<Peer> hasNoOrSameBlock = peer -> {
 		final BlockData latestBlockData = getInstance().getChainTip();
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
-		return peerChainTipData == null || peerChainTipData.getLastBlockSignature() == null || Arrays.equals(latestBlockData.getSignature(), peerChainTipData.getLastBlockSignature());
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
+		return peerChainTipData == null || peerChainTipData.getSignature() == null || Arrays.equals(latestBlockData.getSignature(), peerChainTipData.getSignature());
 	};
 
 	public static final Predicate<Peer> hasOnlyGenesisBlock = peer -> {
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
-		return peerChainTipData == null || peerChainTipData.getLastHeight() == null || peerChainTipData.getLastHeight() == 1;
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
+		return peerChainTipData == null || peerChainTipData.getHeight() == 1;
 	};
 
 	public static final Predicate<Peer> hasInferiorChainTip = peer -> {
-		final PeerChainTipData peerChainTipData = peer.getChainTipData();
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
 		final List<ByteArray> inferiorChainTips = Synchronizer.getInstance().inferiorChainSignatures;
-		return peerChainTipData == null || peerChainTipData.getLastBlockSignature() == null || inferiorChainTips.contains(ByteArray.wrap(peerChainTipData.getLastBlockSignature()));
+		return peerChainTipData == null || peerChainTipData.getSignature() == null || inferiorChainTips.contains(ByteArray.wrap(peerChainTipData.getSignature()));
 	};
 
 	public static final Predicate<Peer> hasOldVersion = peer -> {
@@ -753,6 +757,28 @@ public class Controller extends Thread {
 		return peer.isAtLeastVersion(minPeerVersion) == false;
 	};
 
+	public static final Predicate<Peer> hasInvalidSigner = peer -> {
+		final BlockSummaryData peerChainTipData = peer.getChainTipData();
+		if (peerChainTipData == null)
+			return true;
+
+		try (Repository repository = RepositoryManager.getRepository()) {
+			return Account.getRewardShareEffectiveMintingLevel(repository, peerChainTipData.getMinterPublicKey()) == 0;
+		} catch (DataException e) {
+			return true;
+		}
+	};
+
+	public static final Predicate<Peer> wasRecentlyTooDivergent = peer -> {
+		Long now = NTP.getTime();
+		Long peerLastTooDivergentTime = peer.getLastTooDivergentTime();
+		if (now == null || peerLastTooDivergentTime == null)
+			return false;
+
+		// Exclude any peers that were TOO_DIVERGENT in the last 5 mins
+		return (now - peerLastTooDivergentTime < 5 * 60 * 1000L);
+	};
+
 	private long getRandomRepositoryMaintenanceInterval() {
 		final long minInterval = Settings.getInstance().getRepositoryMaintenanceMinInterval();
 		final long maxInterval = Settings.getInstance().getRepositoryMaintenanceMaxInterval();
@@ -835,6 +861,12 @@ public class Controller extends Thread {
 		String tooltip = String.format("%s - %d %s", actionText, numberOfPeers, connectionsText);
 		if (!Settings.getInstance().isLite()) {
 			tooltip = tooltip.concat(String.format(" - %s %d", heightText, height));
+
+			final Integer blocksRemaining = Synchronizer.getInstance().getBlocksRemaining();
+			if (blocksRemaining != null && blocksRemaining > 0) {
+				String blocksRemainingText = Translator.INSTANCE.translate("SysTray", "BLOCKS_REMAINING");
+				tooltip = tooltip.concat(String.format(" - %d %s", blocksRemaining, blocksRemainingText));
+			}
 		}
 		tooltip = tooltip.concat(String.format("\n%s: %s", Translator.INSTANCE.translate("SysTray", "BUILD_VERSION"), this.buildVersion));
 		SysTray.getInstance().setToolTipText(tooltip);
@@ -1007,8 +1039,7 @@ public class Controller extends Thread {
 		network.broadcast(peer -> peer.isOutbound() ? network.buildPeersMessage(peer) : new GetPeersMessage());
 
 		// Send our current height
-		BlockData latestBlockData = getChainTip();
-		network.broadcast(peer -> network.buildHeightMessage(peer, latestBlockData));
+		network.broadcastOurChain();
 
 		// Request unconfirmed transaction signatures, but only if we're up-to-date.
 		// If we're NOT up-to-date then priority is synchronizing first
@@ -1215,6 +1246,10 @@ public class Controller extends Thread {
 				onNetworkHeightV2Message(peer, message);
 				break;
 
+			case BLOCK_SUMMARIES_V2:
+				onNetworkBlockSummariesV2Message(peer, message);
+				break;
+
 			case GET_TRANSACTION:
 				TransactionImporter.getInstance().onNetworkGetTransactionMessage(peer, message);
 				break;
@@ -1232,25 +1267,20 @@ public class Controller extends Thread {
 				break;
 
 			case GET_ONLINE_ACCOUNTS:
-				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsMessage(peer, message);
-				break;
-
 			case ONLINE_ACCOUNTS:
-				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsMessage(peer, message);
-				break;
-
 			case GET_ONLINE_ACCOUNTS_V2:
-				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsV2Message(peer, message);
-				break;
-
 			case ONLINE_ACCOUNTS_V2:
-				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsV2Message(peer, message);
+				// No longer supported - to be eventually removed
 				break;
 
 			case GET_ONLINE_ACCOUNTS_V3:
 				OnlineAccountsManager.getInstance().onNetworkGetOnlineAccountsV3Message(peer, message);
 				break;
 
+			case ONLINE_ACCOUNTS_V3:
+				OnlineAccountsManager.getInstance().onNetworkOnlineAccountsV3Message(peer, message);
+				break;
+
 			case GET_ARBITRARY_DATA:
 				// Not currently supported
 				break;
@@ -1374,8 +1404,10 @@ public class Controller extends Thread {
 				// Send valid, yet unexpected message type in response, so peer's synchronizer doesn't have to wait for timeout
 				LOGGER.debug(() -> String.format("Sending 'block unknown' response to peer %s for GET_BLOCK request for unknown block %s", peer, Base58.encode(signature)));
 
-				// We'll send empty block summaries message as it's very short
-				Message blockUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// Send generic 'unknown' message as it's very short
+				Message blockUnknownMessage = peer.getPeersVersion() >= GenericUnknownMessage.MINIMUM_PEER_VERSION
+						? new GenericUnknownMessage()
+						: new BlockSummariesMessage(Collections.emptyList());
 				blockUnknownMessage.setId(message.getId());
 				if (!peer.sendMessage(blockUnknownMessage))
 					peer.disconnect("failed to send block-unknown response");
@@ -1424,11 +1456,15 @@ public class Controller extends Thread {
 		this.stats.getBlockSummariesStats.requests.incrementAndGet();
 
 		// If peer's parent signature matches our latest block signature
-		// then we can short-circuit with an empty response
+		// then we have no blocks after that and can short-circuit with an empty response
 		BlockData chainTip = getChainTip();
 		if (chainTip != null && Arrays.equals(parentSignature, chainTip.getSignature())) {
-			Message blockSummariesMessage = new BlockSummariesMessage(Collections.emptyList());
+			Message blockSummariesMessage = peer.getPeersVersion() >= BlockSummariesV2Message.MINIMUM_PEER_VERSION
+					? new BlockSummariesV2Message(Collections.emptyList())
+					: new BlockSummariesMessage(Collections.emptyList());
+
 			blockSummariesMessage.setId(message.getId());
+
 			if (!peer.sendMessage(blockSummariesMessage))
 				peer.disconnect("failed to send block summaries");
 
@@ -1484,7 +1520,9 @@ public class Controller extends Thread {
 				this.stats.getBlockSummariesStats.fullyFromCache.incrementAndGet();
 		}
 
-		Message blockSummariesMessage = new BlockSummariesMessage(blockSummaries);
+		Message blockSummariesMessage = peer.getPeersVersion() >= BlockSummariesV2Message.MINIMUM_PEER_VERSION
+				? new BlockSummariesV2Message(blockSummaries)
+				: new BlockSummariesMessage(blockSummaries);
 		blockSummariesMessage.setId(message.getId());
 		if (!peer.sendMessage(blockSummariesMessage))
 			peer.disconnect("failed to send block summaries");
@@ -1559,18 +1597,59 @@ public class Controller extends Thread {
 			// If peer is inbound and we've not updated their height
 			// then this is probably their initial HEIGHT_V2 message
 			// so they need a corresponding HEIGHT_V2 message from us
-			if (!peer.isOutbound() && (peer.getChainTipData() == null || peer.getChainTipData().getLastHeight() == null))
-				peer.sendMessage(Network.getInstance().buildHeightMessage(peer, getChainTip()));
+			if (!peer.isOutbound() && peer.getChainTipData() == null) {
+				Message responseMessage = Network.getInstance().buildHeightOrChainTipInfo(peer);
+
+				if (responseMessage == null || !peer.sendMessage(responseMessage)) {
+					peer.disconnect("failed to send our chain tip info");
+					return;
+				}
+			}
 		}
 
 		// Update peer chain tip data
-		PeerChainTipData newChainTipData = new PeerChainTipData(heightV2Message.getHeight(), heightV2Message.getSignature(), heightV2Message.getTimestamp(), heightV2Message.getMinterPublicKey());
+		BlockSummaryData newChainTipData = new BlockSummaryData(heightV2Message.getHeight(), heightV2Message.getSignature(), heightV2Message.getMinterPublicKey(), heightV2Message.getTimestamp());
 		peer.setChainTipData(newChainTipData);
 
 		// Potentially synchronize
 		Synchronizer.getInstance().requestSync();
 	}
 
+	private void onNetworkBlockSummariesV2Message(Peer peer, Message message) {
+		BlockSummariesV2Message blockSummariesV2Message = (BlockSummariesV2Message) message;
+
+		if (!Settings.getInstance().isLite()) {
+			// If peer is inbound and we've not updated their height
+			// then this is probably their initial BLOCK_SUMMARIES_V2 message
+			// so they need a corresponding BLOCK_SUMMARIES_V2 message from us
+			if (!peer.isOutbound() && peer.getChainTipData() == null) {
+				Message responseMessage = Network.getInstance().buildHeightOrChainTipInfo(peer);
+
+				if (responseMessage == null || !peer.sendMessage(responseMessage)) {
+					peer.disconnect("failed to send our chain tip info");
+					return;
+				}
+			}
+		}
+
+		if (message.hasId()) {
+			/*
+			 * Experimental proof-of-concept: discard messages with ID
+			 * These are 'late' reply messages received after timeout has expired,
+			 * having been passed upwards from Peer to Network to Controller.
+			 * Hence, these are NOT simple "here's my chain tip" broadcasts from other peers.
+			 */
+			LOGGER.debug("Discarding late {} message with ID {} from {}", message.getType().name(), message.getId(), peer);
+			return;
+		}
+
+		// Update peer chain tip data
+		peer.setChainTipSummaries(blockSummariesV2Message.getBlockSummaries());
+
+		// Potentially synchronize
+		Synchronizer.getInstance().requestSync();
+	}
+
 	private void onNetworkGetAccountMessage(Peer peer, Message message) {
 		GetAccountMessage getAccountMessage = (GetAccountMessage) message;
 		String address = getAccountMessage.getAddress();
@@ -1586,8 +1665,8 @@ public class Controller extends Thread {
 				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
 				LOGGER.debug(() -> String.format("Sending 'account unknown' response to peer %s for GET_ACCOUNT request for unknown account %s", peer, address));
 
-				// We'll send empty block summaries message as it's very short
-				Message accountUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// Send generic 'unknown' message as it's very short
+				Message accountUnknownMessage = new GenericUnknownMessage();
 				accountUnknownMessage.setId(message.getId());
 				if (!peer.sendMessage(accountUnknownMessage))
 					peer.disconnect("failed to send account-unknown response");
@@ -1622,8 +1701,8 @@ public class Controller extends Thread {
 				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
 				LOGGER.debug(() -> String.format("Sending 'account unknown' response to peer %s for GET_ACCOUNT_BALANCE request for unknown account %s and asset ID %d", peer, address, assetId));
 
-				// We'll send empty block summaries message as it's very short
-				Message accountUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// Send generic 'unknown' message as it's very short
+				Message accountUnknownMessage = new GenericUnknownMessage();
 				accountUnknownMessage.setId(message.getId());
 				if (!peer.sendMessage(accountUnknownMessage))
 					peer.disconnect("failed to send account-unknown response");
@@ -1666,8 +1745,8 @@ public class Controller extends Thread {
 				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
 				LOGGER.debug(() -> String.format("Sending 'account unknown' response to peer %s for GET_ACCOUNT_TRANSACTIONS request for unknown account %s", peer, address));
 
-				// We'll send empty block summaries message as it's very short
-				Message accountUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// Send generic 'unknown' message as it's very short
+				Message accountUnknownMessage = new GenericUnknownMessage();
 				accountUnknownMessage.setId(message.getId());
 				if (!peer.sendMessage(accountUnknownMessage))
 					peer.disconnect("failed to send account-unknown response");
@@ -1703,8 +1782,8 @@ public class Controller extends Thread {
 				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
 				LOGGER.debug(() -> String.format("Sending 'account unknown' response to peer %s for GET_ACCOUNT_NAMES request for unknown account %s", peer, address));
 
-				// We'll send empty block summaries message as it's very short
-				Message accountUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// Send generic 'unknown' message as it's very short
+				Message accountUnknownMessage = new GenericUnknownMessage();
 				accountUnknownMessage.setId(message.getId());
 				if (!peer.sendMessage(accountUnknownMessage))
 					peer.disconnect("failed to send account-unknown response");
@@ -1738,8 +1817,8 @@ public class Controller extends Thread {
 				// Send valid, yet unexpected message type in response, so peer doesn't have to wait for timeout
 				LOGGER.debug(() -> String.format("Sending 'name unknown' response to peer %s for GET_NAME request for unknown name %s", peer, name));
 
-				// We'll send empty block summaries message as it's very short
-				Message nameUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+				// Send generic 'unknown' message as it's very short
+				Message nameUnknownMessage = new GenericUnknownMessage();
 				nameUnknownMessage.setId(message.getId());
 				if (!peer.sendMessage(nameUnknownMessage))
 					peer.disconnect("failed to send name-unknown response");
@@ -1787,14 +1866,14 @@ public class Controller extends Thread {
 				continue;
 			}
 
-			final PeerChainTipData peerChainTipData = peer.getChainTipData();
+			BlockSummaryData peerChainTipData = peer.getChainTipData();
 			if (peerChainTipData == null) {
 				iterator.remove();
 				continue;
 			}
 
 			// Disregard peers that don't have a recent block
-			if (peerChainTipData.getLastBlockTimestamp() == null || peerChainTipData.getLastBlockTimestamp() < minLatestBlockTimestamp) {
+			if (peerChainTipData.getTimestamp() == null || peerChainTipData.getTimestamp() < minLatestBlockTimestamp) {
 				iterator.remove();
 				continue;
 			}
@@ -1822,6 +1901,10 @@ public class Controller extends Thread {
 		if (latestBlockData == null || latestBlockData.getTimestamp() < minLatestBlockTimestamp)
 			return false;
 
+		if (Settings.getInstance().isSingleNodeTestnet())
+			// Single node testnets won't have peers, so we can assume up to date from this point
+			return true;
+
 		// Needs a mutable copy of the unmodifiableList
 		List<Peer> peers = new ArrayList<>(Network.getInstance().getImmutableHandshakedPeers());
 		if (peers == null)

src/main/java/org/qortal/controller/OnlineAccountsManager.java

@@ -9,6 +9,7 @@ import org.qortal.account.PrivateKeyAccount;
 import org.qortal.block.Block;
 import org.qortal.block.BlockChain;
 import org.qortal.crypto.Crypto;
+import org.qortal.crypto.MemoryPoW;
 import org.qortal.crypto.Qortal25519Extras;
 import org.qortal.data.account.MintingAccountData;
 import org.qortal.data.account.RewardShareData;
@@ -19,10 +20,13 @@ import org.qortal.network.message.*;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
+import org.qortal.settings.Settings;
 import org.qortal.utils.Base58;
 import org.qortal.utils.NTP;
 import org.qortal.utils.NamedThreadFactory;
 
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
 import java.util.*;
 import java.util.concurrent.*;
 import java.util.stream.Collectors;
@@ -49,13 +53,30 @@ public class OnlineAccountsManager {
      */
     private static final int MAX_BLOCKS_CACHED_ONLINE_ACCOUNTS = 3;
 
-    private static final long ONLINE_ACCOUNTS_QUEUE_INTERVAL = 100L; //ms
+    private static final long ONLINE_ACCOUNTS_QUEUE_INTERVAL = 100L; // ms
     private static final long ONLINE_ACCOUNTS_TASKS_INTERVAL = 10 * 1000L; // ms
-    private static final long ONLINE_ACCOUNTS_LEGACY_BROADCAST_INTERVAL = 60 * 1000L; // ms
-    private static final long ONLINE_ACCOUNTS_BROADCAST_INTERVAL = 15 * 1000L; // ms
+    private static final long ONLINE_ACCOUNTS_COMPUTE_INTERVAL = 5 * 1000L; // ms
+    private static final long ONLINE_ACCOUNTS_BROADCAST_INTERVAL = 60 * 1000L; // ms
+    // After switching to a new online timestamp, we "burst" the online accounts requests
+    // at an increased interval for a specified amount of time
+    private static final long ONLINE_ACCOUNTS_BROADCAST_BURST_INTERVAL = 5 * 1000L; // ms
+    private static final long ONLINE_ACCOUNTS_BROADCAST_BURST_LENGTH = 5 * 60 * 1000L; // ms
 
-    private static final long ONLINE_ACCOUNTS_V2_PEER_VERSION = 0x0300020000L; // v3.2.0
-    private static final long ONLINE_ACCOUNTS_V3_PEER_VERSION = 0x0300040000L; // v3.4.0
+    private static final long ONLINE_ACCOUNTS_COMPUTE_INITIAL_SLEEP_INTERVAL = 30 * 1000L; // ms
+
+    // MemoryPoW - mainnet
+    public static final int POW_BUFFER_SIZE = 1 * 1024 * 1024; // bytes
+    public static final int POW_DIFFICULTY_V1 = 18; // leading zero bits
+    public static final int POW_DIFFICULTY_V2 = 19; // leading zero bits
+
+    // MemoryPoW - testnet
+    public static final int POW_BUFFER_SIZE_TESTNET = 1 * 1024 * 1024; // bytes
+    public static final int POW_DIFFICULTY_TESTNET = 5; // leading zero bits
+
+    // IMPORTANT: if we ever need to dynamically modify the buffer size using a feature trigger, the
+    // pre-allocated buffer below will NOT work, and we should instead use a dynamically allocated
+    // one for the transition period.
+    private static long[] POW_VERIFY_WORK_BUFFER = new long[getPoWBufferSize() / 8];
 
     private final ScheduledExecutorService executor = Executors.newScheduledThreadPool(4, new NamedThreadFactory("OnlineAccounts"));
     private volatile boolean isStopping = false;
@@ -77,6 +98,8 @@ public class OnlineAccountsManager {
      */
     private final SortedMap<Long, Set<OnlineAccountData>> latestBlocksOnlineAccounts = new ConcurrentSkipListMap<>();
 
+    private long lastOnlineAccountsRequest = 0;
+
     private boolean hasOurOnlineAccounts = false;
 
     public static long getOnlineTimestampModulus() {
@@ -95,6 +118,27 @@ public class OnlineAccountsManager {
         return (now / onlineTimestampModulus) * onlineTimestampModulus;
     }
 
+    public static long toOnlineAccountTimestamp(long timestamp) {
+        return (timestamp / getOnlineTimestampModulus()) * getOnlineTimestampModulus();
+    }
+
+    private static int getPoWBufferSize() {
+        if (Settings.getInstance().isTestNet())
+            return POW_BUFFER_SIZE_TESTNET;
+
+        return POW_BUFFER_SIZE;
+    }
+
+    private static int getPoWDifficulty(long timestamp) {
+        if (Settings.getInstance().isTestNet())
+            return POW_DIFFICULTY_TESTNET;
+
+        if (timestamp >= BlockChain.getInstance().getIncreaseOnlineAccountsDifficultyTimestamp())
+            return POW_DIFFICULTY_V2;
+
+        return POW_DIFFICULTY_V1;
+    }
+
     private OnlineAccountsManager() {
     }
 
@@ -110,16 +154,16 @@ public class OnlineAccountsManager {
         // Expire old online accounts signatures
         executor.scheduleAtFixedRate(this::expireOldOnlineAccounts, ONLINE_ACCOUNTS_TASKS_INTERVAL, ONLINE_ACCOUNTS_TASKS_INTERVAL, TimeUnit.MILLISECONDS);
 
-        // Send our online accounts
-        executor.scheduleAtFixedRate(this::sendOurOnlineAccountsInfo, ONLINE_ACCOUNTS_BROADCAST_INTERVAL, ONLINE_ACCOUNTS_BROADCAST_INTERVAL, TimeUnit.MILLISECONDS);
-
-        // Request online accounts from peers (legacy)
-        executor.scheduleAtFixedRate(this::requestLegacyRemoteOnlineAccounts, ONLINE_ACCOUNTS_LEGACY_BROADCAST_INTERVAL, ONLINE_ACCOUNTS_LEGACY_BROADCAST_INTERVAL, TimeUnit.MILLISECONDS);
-        // Request online accounts from peers (V3+)
-        executor.scheduleAtFixedRate(this::requestRemoteOnlineAccounts, ONLINE_ACCOUNTS_BROADCAST_INTERVAL, ONLINE_ACCOUNTS_BROADCAST_INTERVAL, TimeUnit.MILLISECONDS);
+        // Request online accounts from peers
+        executor.scheduleAtFixedRate(this::requestRemoteOnlineAccounts, ONLINE_ACCOUNTS_BROADCAST_BURST_INTERVAL, ONLINE_ACCOUNTS_BROADCAST_BURST_INTERVAL, TimeUnit.MILLISECONDS);
 
         // Process import queue
         executor.scheduleWithFixedDelay(this::processOnlineAccountsImportQueue, ONLINE_ACCOUNTS_QUEUE_INTERVAL, ONLINE_ACCOUNTS_QUEUE_INTERVAL, TimeUnit.MILLISECONDS);
+
+        // Send our online accounts (using increased initial delay)
+        // This allows some time for initial online account lists to be retrieved, and
+        // reduces the chances of the same nonce being computed twice
+        executor.scheduleAtFixedRate(this::sendOurOnlineAccountsInfo, ONLINE_ACCOUNTS_COMPUTE_INITIAL_SLEEP_INTERVAL, ONLINE_ACCOUNTS_COMPUTE_INTERVAL, TimeUnit.MILLISECONDS);
     }
 
     public void shutdown() {
@@ -139,18 +183,17 @@ public class OnlineAccountsManager {
             return;
 
         byte[] timestampBytes = Longs.toByteArray(onlineAccountsTimestamp);
-        final boolean useAggregateCompatibleSignature = onlineAccountsTimestamp >= BlockChain.getInstance().getAggregateSignatureTimestamp();
 
         Set<OnlineAccountData> replacementAccounts = new HashSet<>();
         for (PrivateKeyAccount onlineAccount : onlineAccounts) {
             // Check mintingAccount is actually reward-share?
 
-            byte[] signature = useAggregateCompatibleSignature
-                    ? Qortal25519Extras.signForAggregation(onlineAccount.getPrivateKey(), timestampBytes)
-                    : onlineAccount.sign(timestampBytes);
+            byte[] signature = Qortal25519Extras.signForAggregation(onlineAccount.getPrivateKey(), timestampBytes);
             byte[] publicKey = onlineAccount.getPublicKey();
 
-            OnlineAccountData ourOnlineAccountData = new OnlineAccountData(onlineAccountsTimestamp, signature, publicKey);
+            Integer nonce = new Random().nextInt(500000);
+
+            OnlineAccountData ourOnlineAccountData = new OnlineAccountData(onlineAccountsTimestamp, signature, publicKey, nonce);
             replacementAccounts.add(ourOnlineAccountData);
         }
 
@@ -168,28 +211,86 @@ public class OnlineAccountsManager {
         LOGGER.debug("Processing online accounts import queue (size: {})", this.onlineAccountsImportQueue.size());
 
         Set<OnlineAccountData> onlineAccountsToAdd = new HashSet<>();
+        Set<OnlineAccountData> onlineAccountsToRemove = new HashSet<>();
         try (final Repository repository = RepositoryManager.getRepository()) {
             for (OnlineAccountData onlineAccountData : this.onlineAccountsImportQueue) {
                 if (isStopping)
                     return;
 
+                // Skip this account if it's already validated
+                Set<OnlineAccountData> onlineAccounts = this.currentOnlineAccounts.get(onlineAccountData.getTimestamp());
+                if (onlineAccounts != null && onlineAccounts.contains(onlineAccountData)) {
+                    // We have already validated this online account
+                    onlineAccountsImportQueue.remove(onlineAccountData);
+                    continue;
+                }
+
                 boolean isValid = this.isValidCurrentAccount(repository, onlineAccountData);
                 if (isValid)
                     onlineAccountsToAdd.add(onlineAccountData);
 
-                // Remove from queue
-                onlineAccountsImportQueue.remove(onlineAccountData);
+                // Don't remove from the queue yet - we'll do this at the end of the process
+                // This prevents duplicates being added to the queue whilst it's being processed
+                onlineAccountsToRemove.add(onlineAccountData);
             }
         } catch (DataException e) {
             LOGGER.error("Repository issue while verifying online accounts", e);
-        }
 
-        if (!onlineAccountsToAdd.isEmpty()) {
-            LOGGER.debug("Merging {} validated online accounts from import queue", onlineAccountsToAdd.size());
-            addAccounts(onlineAccountsToAdd);
+        } finally {
+            if (!onlineAccountsToAdd.isEmpty()) {
+                LOGGER.debug("Merging {} validated online accounts from import queue", onlineAccountsToAdd.size());
+                addAccounts(onlineAccountsToAdd);
+            }
+            onlineAccountsImportQueue.removeAll(onlineAccountsToRemove);
         }
     }
 
+    /**
+     * Check if supplied onlineAccountData is superior (i.e. has a nonce value) than existing record.
+     * Two entries are considered equal even if the nonce differs, to prevent multiple variations
+     * co-existing. For this reason, we need to be able to check if a new OnlineAccountData entry should
+     * replace the existing one, which may be missing the nonce.
+     * @param onlineAccountData
+     * @return true if supplied data is superior to existing entry
+     */
+    private boolean isOnlineAccountsDataSuperior(OnlineAccountData onlineAccountData) {
+        if (onlineAccountData.getNonce() == null || onlineAccountData.getNonce() < 0) {
+            // New online account data has no usable nonce value, so it won't be better than anything we already have
+            return false;
+        }
+
+        // New online account data has a nonce value, so check if there is any existing data to compare against
+        Set<OnlineAccountData> existingOnlineAccountsForTimestamp = this.currentOnlineAccounts.get(onlineAccountData.getTimestamp());
+        if (existingOnlineAccountsForTimestamp == null) {
+            // No existing online accounts data with this timestamp yet
+            return false;
+        }
+
+        // Check if a duplicate entry exists
+        OnlineAccountData existingOnlineAccountData = null;
+        for (OnlineAccountData existingAccount : existingOnlineAccountsForTimestamp) {
+            if (existingAccount.equals(onlineAccountData)) {
+                // Found existing online account data
+                existingOnlineAccountData = existingAccount;
+                break;
+            }
+        }
+
+        if (existingOnlineAccountData == null) {
+            // No existing online accounts data, so nothing to compare
+            return false;
+        }
+
+        if (existingOnlineAccountData.getNonce() == null || existingOnlineAccountData.getNonce() < 0) {
+            // Existing data has no usable nonce value(s) so we want to replace it with the new one
+            return true;
+        }
+
+        // Both new and old data have nonce values so the new data isn't considered superior
+        return false;
+    }
+
+
     // Utilities
 
     public static byte[] xorByteArrayInPlace(byte[] inplaceArray, byte[] otherArray) {
@@ -225,9 +326,7 @@ public class OnlineAccountsManager {
 
         // Verify signature
         byte[] data = Longs.toByteArray(onlineAccountData.getTimestamp());
-        boolean isSignatureValid = onlineAccountTimestamp >= BlockChain.getInstance().getAggregateSignatureTimestamp()
-                ? Qortal25519Extras.verifyAggregated(rewardSharePublicKey, onlineAccountData.getSignature(), data)
-                : Crypto.verify(rewardSharePublicKey, onlineAccountData.getSignature(), data);
+        boolean isSignatureValid = Qortal25519Extras.verifyAggregated(rewardSharePublicKey, onlineAccountData.getSignature(), data);
         if (!isSignatureValid) {
             LOGGER.trace(() -> String.format("Rejecting invalid online account %s", Base58.encode(rewardSharePublicKey)));
             return false;
@@ -248,6 +347,12 @@ public class OnlineAccountsManager {
             return false;
         }
 
+        // Validate mempow
+        if (!getInstance().verifyMemoryPoW(onlineAccountData, POW_VERIFY_WORK_BUFFER)) {
+            LOGGER.trace(() -> String.format("Rejecting online reward-share for account %s due to invalid PoW nonce", mintingAccount.getAddress()));
+            return false;
+        }
+
         return true;
     }
 
@@ -269,7 +374,7 @@ public class OnlineAccountsManager {
         for (var entry : hashesToRebuild.entrySet()) {
             Long timestamp = entry.getKey();
 
-            LOGGER.debug(() -> String.format("Rehashing for timestamp %d and leading bytes %s",
+            LOGGER.trace(() -> String.format("Rehashing for timestamp %d and leading bytes %s",
                             timestamp,
                             entry.getValue().stream().sorted(Byte::compareUnsigned).map(leadingByte -> String.format("%02x", leadingByte)).collect(Collectors.joining(", "))
                     )
@@ -295,7 +400,7 @@ public class OnlineAccountsManager {
             }
         }
 
-        LOGGER.debug(String.format("we have online accounts for timestamps: %s", String.join(", ", this.currentOnlineAccounts.keySet().stream().map(l -> Long.toString(l)).collect(Collectors.joining(", ")))));
+        LOGGER.trace(String.format("we have online accounts for timestamps: %s", String.join(", ", this.currentOnlineAccounts.keySet().stream().map(l -> Long.toString(l)).collect(Collectors.joining(", ")))));
 
         return true;
     }
@@ -305,6 +410,12 @@ public class OnlineAccountsManager {
         long onlineAccountTimestamp = onlineAccountData.getTimestamp();
 
         Set<OnlineAccountData> onlineAccounts = this.currentOnlineAccounts.computeIfAbsent(onlineAccountTimestamp, k -> ConcurrentHashMap.newKeySet());
+
+        boolean isSuperiorEntry = isOnlineAccountsDataSuperior(onlineAccountData);
+        if (isSuperiorEntry)
+            // Remove existing inferior entry so it can be re-added below (it's likely the existing copy is missing a nonce value)
+            onlineAccounts.remove(onlineAccountData);
+
         boolean isNewEntry = onlineAccounts.add(onlineAccountData);
 
         if (isNewEntry)
@@ -329,30 +440,7 @@ public class OnlineAccountsManager {
     }
 
     /**
-     * Request data from other peers. (Pre-V3)
-     */
-    private void requestLegacyRemoteOnlineAccounts() {
-        final Long now = NTP.getTime();
-        if (now == null)
-            return;
-
-        // Don't bother if we're not up to date
-        if (!Controller.getInstance().isUpToDate())
-            return;
-
-        List<OnlineAccountData> mergedOnlineAccounts = Set.copyOf(this.currentOnlineAccounts.values()).stream().flatMap(Set::stream).collect(Collectors.toList());
-
-        Message messageV2 = new GetOnlineAccountsV2Message(mergedOnlineAccounts);
-
-        Network.getInstance().broadcast(peer ->
-                peer.getPeersVersion() < ONLINE_ACCOUNTS_V3_PEER_VERSION
-                        ? messageV2
-                        : null
-        );
-    }
-
-    /**
-     * Request data from other peers. V3+
+     * Request data from other peers
      */
     private void requestRemoteOnlineAccounts() {
         final Long now = NTP.getTime();
@@ -363,13 +451,25 @@ public class OnlineAccountsManager {
         if (!Controller.getInstance().isUpToDate())
             return;
 
-        Message messageV3 = new GetOnlineAccountsV3Message(currentOnlineAccountsHashes);
+        long onlineAccountsTimestamp = getCurrentOnlineAccountTimestamp();
+        if (now - onlineAccountsTimestamp >= ONLINE_ACCOUNTS_BROADCAST_BURST_LENGTH) {
+            // New online timestamp started more than 5 mins ago - we probably don't need to request so frequently
 
-        Network.getInstance().broadcast(peer ->
-                peer.getPeersVersion() >= ONLINE_ACCOUNTS_V3_PEER_VERSION
-                        ? messageV3
-                        : null
-        );
+            if (Controller.uptime() < ONLINE_ACCOUNTS_BROADCAST_BURST_LENGTH) {
+                // The node recently started up, so we should request at the burst interval
+                // This could allow accounts to move around the network more easily when an auto update is occurring
+            }
+            else if (now - lastOnlineAccountsRequest < ONLINE_ACCOUNTS_BROADCAST_INTERVAL) {
+                // We already requested online accounts in the last minute, so no need to request again
+                return;
+            }
+        }
+
+        LOGGER.debug("Requesting online accounts via broadcast...");
+
+        lastOnlineAccountsRequest = now;
+        Message messageV3 = new GetOnlineAccountsV3Message(currentOnlineAccountsHashes);
+        Network.getInstance().broadcast(peer -> messageV3);
     }
 
     /**
@@ -392,13 +492,26 @@ public class OnlineAccountsManager {
             return;
         }
 
+        // 'next' timestamp (prioritize this as it's the most important, if mempow active)
+        final long nextOnlineAccountsTimestamp = toOnlineAccountTimestamp(now) + getOnlineTimestampModulus();
+        boolean success = computeOurAccountsForTimestamp(nextOnlineAccountsTimestamp);
+        if (!success) {
+            // We didn't compute the required nonce value(s), and so can't proceed until they have been retried
+            return;
+        }
+
+        // 'current' timestamp
+        computeOurAccountsForTimestamp(onlineAccountsTimestamp);
+    }
+
+    private boolean computeOurAccountsForTimestamp(long onlineAccountsTimestamp) {
         List<MintingAccountData> mintingAccounts;
         try (final Repository repository = RepositoryManager.getRepository()) {
             mintingAccounts = repository.getAccountRepository().getMintingAccounts();
 
             // We have no accounts to send
             if (mintingAccounts.isEmpty())
-                return;
+                return false;
 
             // Only active reward-shares allowed
             Iterator<MintingAccountData> iterator = mintingAccounts.iterator();
@@ -421,25 +534,66 @@ public class OnlineAccountsManager {
             }
         } catch (DataException e) {
             LOGGER.warn(String.format("Repository issue trying to fetch minting accounts: %s", e.getMessage()));
-            return;
+            return false;
         }
 
-        final boolean useAggregateCompatibleSignature = onlineAccountsTimestamp >= BlockChain.getInstance().getAggregateSignatureTimestamp();
-
         byte[] timestampBytes = Longs.toByteArray(onlineAccountsTimestamp);
         List<OnlineAccountData> ourOnlineAccounts = new ArrayList<>();
 
+        int remaining = mintingAccounts.size();
         for (MintingAccountData mintingAccountData : mintingAccounts) {
+            remaining--;
             byte[] privateKey = mintingAccountData.getPrivateKey();
             byte[] publicKey = Crypto.toPublicKey(privateKey);
 
-            byte[] signature = useAggregateCompatibleSignature
-                    ? Qortal25519Extras.signForAggregation(privateKey, timestampBytes)
-                    : Crypto.sign(privateKey, timestampBytes);
+            // We don't want to compute the online account nonce and signature again if it already exists
+            Set<OnlineAccountData> onlineAccounts = this.currentOnlineAccounts.computeIfAbsent(onlineAccountsTimestamp, k -> ConcurrentHashMap.newKeySet());
+            boolean alreadyExists = onlineAccounts.stream().anyMatch(a -> Arrays.equals(a.getPublicKey(), publicKey));
+            if (alreadyExists) {
+                this.hasOurOnlineAccounts = true;
+
+                if (remaining > 0) {
+                    // Move on to next account
+                    continue;
+                }
+                else {
+                    // Everything exists, so return true
+                    return true;
+                }
+            }
+
+            // Generate bytes for mempow
+            byte[] mempowBytes;
+            try {
+                mempowBytes = this.getMemoryPoWBytes(publicKey, onlineAccountsTimestamp);
+            }
+            catch (IOException e) {
+                LOGGER.info("Unable to create bytes for MemoryPoW. Moving on to next account...");
+                continue;
+            }
+
+            // Compute nonce
+            Integer nonce;
+            try {
+                nonce = this.computeMemoryPoW(mempowBytes, publicKey, onlineAccountsTimestamp);
+                if (nonce == null) {
+                    // A nonce is required
+                    return false;
+                }
+            } catch (TimeoutException e) {
+                LOGGER.info(String.format("Timed out computing nonce for account %.8s", Base58.encode(publicKey)));
+                return false;
+            }
+
+            byte[] signature = Qortal25519Extras.signForAggregation(privateKey, timestampBytes);
 
             // Our account is online
-            OnlineAccountData ourOnlineAccountData = new OnlineAccountData(onlineAccountsTimestamp, signature, publicKey);
-            ourOnlineAccounts.add(ourOnlineAccountData);
+            OnlineAccountData ourOnlineAccountData = new OnlineAccountData(onlineAccountsTimestamp, signature, publicKey, nonce);
+
+            // Make sure to verify before adding
+            if (verifyMemoryPoW(ourOnlineAccountData, null)) {
+                ourOnlineAccounts.add(ourOnlineAccountData);
+            }
         }
 
         this.hasOurOnlineAccounts = !ourOnlineAccounts.isEmpty();
@@ -447,23 +601,72 @@ public class OnlineAccountsManager {
         boolean hasInfoChanged = addAccounts(ourOnlineAccounts);
 
         if (!hasInfoChanged)
-            return;
+            return false;
 
-        Message messageV1 = new OnlineAccountsMessage(ourOnlineAccounts);
-        Message messageV2 = new OnlineAccountsV2Message(ourOnlineAccounts);
-        Message messageV3 = new OnlineAccountsV2Message(ourOnlineAccounts); // TODO: V3 message
-
-        Network.getInstance().broadcast(peer ->
-                peer.getPeersVersion() >= ONLINE_ACCOUNTS_V3_PEER_VERSION
-                        ? messageV3
-                        : peer.getPeersVersion() >= ONLINE_ACCOUNTS_V2_PEER_VERSION
-                        ? messageV2
-                        : messageV1
-        );
+        Network.getInstance().broadcast(peer -> new OnlineAccountsV3Message(ourOnlineAccounts));
 
         LOGGER.debug("Broadcasted {} online account{} with timestamp {}", ourOnlineAccounts.size(), (ourOnlineAccounts.size() != 1 ? "s" : ""), onlineAccountsTimestamp);
+
+        return true;
     }
 
+
+
+    // MemoryPoW
+
+    private byte[] getMemoryPoWBytes(byte[] publicKey, long onlineAccountsTimestamp) throws IOException {
+        byte[] timestampBytes = Longs.toByteArray(onlineAccountsTimestamp);
+
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        outputStream.write(publicKey);
+        outputStream.write(timestampBytes);
+
+        return outputStream.toByteArray();
+    }
+
+    private Integer computeMemoryPoW(byte[] bytes, byte[] publicKey, long onlineAccountsTimestamp) throws TimeoutException {
+        LOGGER.info(String.format("Computing nonce for account %.8s and timestamp %d...", Base58.encode(publicKey), onlineAccountsTimestamp));
+
+        // Calculate the time until the next online timestamp and use it as a timeout when computing the nonce
+        Long startTime = NTP.getTime();
+        final long nextOnlineAccountsTimestamp = toOnlineAccountTimestamp(startTime) + getOnlineTimestampModulus();
+        long timeUntilNextTimestamp = nextOnlineAccountsTimestamp - startTime;
+
+        int difficulty = getPoWDifficulty(onlineAccountsTimestamp);
+        Integer nonce = MemoryPoW.compute2(bytes, getPoWBufferSize(), difficulty, timeUntilNextTimestamp);
+
+        double totalSeconds = (NTP.getTime() - startTime) / 1000.0f;
+        int minutes = (int) ((totalSeconds % 3600) / 60);
+        int seconds = (int) (totalSeconds % 60);
+        double hashRate = nonce / totalSeconds;
+
+        LOGGER.info(String.format("Computed nonce for timestamp %d and account %.8s: %d. Buffer size: %d. Difficulty: %d. " +
+                        "Time taken: %02d:%02d. Hashrate: %f", onlineAccountsTimestamp, Base58.encode(publicKey),
+                nonce, getPoWBufferSize(), difficulty, minutes, seconds, hashRate));
+
+        return nonce;
+    }
+
+    public boolean verifyMemoryPoW(OnlineAccountData onlineAccountData, long[] workBuffer) {
+        // Require a valid nonce value
+        if (onlineAccountData.getNonce() == null || onlineAccountData.getNonce() < 0) {
+            return false;
+        }
+
+        int nonce = onlineAccountData.getNonce();
+
+        byte[] mempowBytes;
+        try {
+            mempowBytes = this.getMemoryPoWBytes(onlineAccountData.getPublicKey(), onlineAccountData.getTimestamp());
+        } catch (IOException e) {
+            return false;
+        }
+
+        // Verify the nonce
+        return MemoryPoW.verify2(mempowBytes, workBuffer, getPoWBufferSize(), getPoWDifficulty(onlineAccountData.getTimestamp()), nonce);
+    }
+
+
     /**
      * Returns whether online accounts manager has any online accounts with timestamp recent enough to be considered currently online.
      */
@@ -498,7 +701,7 @@ public class OnlineAccountsManager {
      */
     // Block::mint() - only wants online accounts with (online) timestamp that matches block's (online) timestamp so they can be added to new block
     public List<OnlineAccountData> getOnlineAccounts(long onlineTimestamp) {
-        LOGGER.info(String.format("caller's timestamp: %d, our timestamps: %s", onlineTimestamp, String.join(", ", this.currentOnlineAccounts.keySet().stream().map(l -> Long.toString(l)).collect(Collectors.joining(", ")))));
+        LOGGER.debug(String.format("caller's timestamp: %d, our timestamps: %s", onlineTimestamp, String.join(", ", this.currentOnlineAccounts.keySet().stream().map(l -> Long.toString(l)).collect(Collectors.joining(", ")))));
 
         return new ArrayList<>(Set.copyOf(this.currentOnlineAccounts.getOrDefault(onlineTimestamp, Collections.emptySet())));
     }
@@ -544,11 +747,12 @@ public class OnlineAccountsManager {
      * Typically called by {@link Block#areOnlineAccountsValid()}
      */
     public void addBlocksOnlineAccounts(Set<OnlineAccountData> blocksOnlineAccounts, Long timestamp) {
-        // We want to add to 'current' in preference if possible
-        if (this.currentOnlineAccounts.containsKey(timestamp)) {
-            addAccounts(blocksOnlineAccounts);
+        // If these are current accounts, then there is no need to cache them, and should instead rely
+        // on the more complete entries we already have in self.currentOnlineAccounts.
+        // Note: since sig-agg, we no longer have individual signatures included in blocks, so we
+        // mustn't add anything to currentOnlineAccounts from here.
+        if (this.currentOnlineAccounts.containsKey(timestamp))
             return;
-        }
 
         // Add to block cache instead
         this.latestBlocksOnlineAccounts.computeIfAbsent(timestamp, k -> ConcurrentHashMap.newKeySet())
@@ -568,106 +772,6 @@ public class OnlineAccountsManager {
 
     // Network handlers
 
-    public void onNetworkGetOnlineAccountsMessage(Peer peer, Message message) {
-        GetOnlineAccountsMessage getOnlineAccountsMessage = (GetOnlineAccountsMessage) message;
-
-        List<OnlineAccountData> excludeAccounts = getOnlineAccountsMessage.getOnlineAccounts();
-
-        // Send online accounts info, excluding entries with matching timestamp & public key from excludeAccounts
-        List<OnlineAccountData> accountsToSend = Set.copyOf(this.currentOnlineAccounts.values()).stream().flatMap(Set::stream).collect(Collectors.toList());
-        int prefilterSize = accountsToSend.size();
-
-        Iterator<OnlineAccountData> iterator = accountsToSend.iterator();
-        while (iterator.hasNext()) {
-            OnlineAccountData onlineAccountData = iterator.next();
-
-            for (OnlineAccountData excludeAccountData : excludeAccounts) {
-                if (onlineAccountData.getTimestamp() == excludeAccountData.getTimestamp() && Arrays.equals(onlineAccountData.getPublicKey(), excludeAccountData.getPublicKey())) {
-                    iterator.remove();
-                    break;
-                }
-            }
-        }
-
-        if (accountsToSend.isEmpty())
-            return;
-
-        Message onlineAccountsMessage = new OnlineAccountsMessage(accountsToSend);
-        peer.sendMessage(onlineAccountsMessage);
-
-        LOGGER.debug("Sent {} of our {} online accounts to {}", accountsToSend.size(), prefilterSize, peer);
-    }
-
-    public void onNetworkOnlineAccountsMessage(Peer peer, Message message) {
-        OnlineAccountsMessage onlineAccountsMessage = (OnlineAccountsMessage) message;
-
-        List<OnlineAccountData> peersOnlineAccounts = onlineAccountsMessage.getOnlineAccounts();
-        LOGGER.debug("Received {} online accounts from {}", peersOnlineAccounts.size(), peer);
-
-        int importCount = 0;
-
-        // Add any online accounts to the queue that aren't already present
-        for (OnlineAccountData onlineAccountData : peersOnlineAccounts) {
-            boolean isNewEntry = onlineAccountsImportQueue.add(onlineAccountData);
-
-            if (isNewEntry)
-                importCount++;
-        }
-
-        if (importCount > 0)
-            LOGGER.debug("Added {} online accounts to queue", importCount);
-    }
-
-    public void onNetworkGetOnlineAccountsV2Message(Peer peer, Message message) {
-        GetOnlineAccountsV2Message getOnlineAccountsMessage = (GetOnlineAccountsV2Message) message;
-
-        List<OnlineAccountData> excludeAccounts = getOnlineAccountsMessage.getOnlineAccounts();
-
-        // Send online accounts info, excluding entries with matching timestamp & public key from excludeAccounts
-        List<OnlineAccountData> accountsToSend = Set.copyOf(this.currentOnlineAccounts.values()).stream().flatMap(Set::stream).collect(Collectors.toList());
-        int prefilterSize = accountsToSend.size();
-
-        Iterator<OnlineAccountData> iterator = accountsToSend.iterator();
-        while (iterator.hasNext()) {
-            OnlineAccountData onlineAccountData = iterator.next();
-
-            for (OnlineAccountData excludeAccountData : excludeAccounts) {
-                if (onlineAccountData.getTimestamp() == excludeAccountData.getTimestamp() && Arrays.equals(onlineAccountData.getPublicKey(), excludeAccountData.getPublicKey())) {
-                    iterator.remove();
-                    break;
-                }
-            }
-        }
-
-        if (accountsToSend.isEmpty())
-            return;
-
-        Message onlineAccountsMessage = new OnlineAccountsV2Message(accountsToSend);
-        peer.sendMessage(onlineAccountsMessage);
-
-        LOGGER.debug("Sent {} of our {} online accounts to {}", accountsToSend.size(), prefilterSize, peer);
-    }
-
-    public void onNetworkOnlineAccountsV2Message(Peer peer, Message message) {
-        OnlineAccountsV2Message onlineAccountsMessage = (OnlineAccountsV2Message) message;
-
-        List<OnlineAccountData> peersOnlineAccounts = onlineAccountsMessage.getOnlineAccounts();
-        LOGGER.debug("Received {} online accounts from {}", peersOnlineAccounts.size(), peer);
-
-        int importCount = 0;
-
-        // Add any online accounts to the queue that aren't already present
-        for (OnlineAccountData onlineAccountData : peersOnlineAccounts) {
-            boolean isNewEntry = onlineAccountsImportQueue.add(onlineAccountData);
-
-            if (isNewEntry)
-                importCount++;
-        }
-
-        if (importCount > 0)
-            LOGGER.debug("Added {} online accounts to queue", importCount);
-    }
-
     public void onNetworkGetOnlineAccountsV3Message(Peer peer, Message message) {
         GetOnlineAccountsV3Message getOnlineAccountsMessage = (GetOnlineAccountsV3Message) message;
 
@@ -688,7 +792,7 @@ public class OnlineAccountsManager {
                 Set<OnlineAccountData> timestampsOnlineAccounts = this.currentOnlineAccounts.getOrDefault(timestamp, Collections.emptySet());
                 outgoingOnlineAccounts.addAll(timestampsOnlineAccounts);
 
-                LOGGER.debug(() -> String.format("Going to send all %d online accounts for timestamp %d", timestampsOnlineAccounts.size(), timestamp));
+                LOGGER.trace(() -> String.format("Going to send all %d online accounts for timestamp %d", timestampsOnlineAccounts.size(), timestamp));
             } else {
                 // Quick cache of which leading bytes to send so we only have to filter once
                 Set<Byte> outgoingLeadingBytes = new HashSet<>();
@@ -712,7 +816,7 @@ public class OnlineAccountsManager {
                         .forEach(outgoingOnlineAccounts::add);
 
                 if (outgoingOnlineAccounts.size() > beforeAddSize)
-                    LOGGER.debug(String.format("Going to send %d online accounts for timestamp %d and leading bytes %s",
+                    LOGGER.trace(String.format("Going to send %d online accounts for timestamp %d and leading bytes %s",
                             outgoingOnlineAccounts.size() - beforeAddSize,
                             timestamp,
                             outgoingLeadingBytes.stream().sorted(Byte::compareUnsigned).map(leadingByte -> String.format("%02x", leadingByte)).collect(Collectors.joining(", "))
@@ -721,9 +825,34 @@ public class OnlineAccountsManager {
             }
         }
 
-        Message onlineAccountsMessage = new OnlineAccountsV2Message(outgoingOnlineAccounts); // TODO: V3 message
-        peer.sendMessage(onlineAccountsMessage);
+        peer.sendMessage(new OnlineAccountsV3Message(outgoingOnlineAccounts));
 
-        LOGGER.debug("Sent {} online accounts to {}", outgoingOnlineAccounts.size(), peer);
+        LOGGER.trace("Sent {} online accounts to {}", outgoingOnlineAccounts.size(), peer);
+    }
+
+    public void onNetworkOnlineAccountsV3Message(Peer peer, Message message) {
+        OnlineAccountsV3Message onlineAccountsMessage = (OnlineAccountsV3Message) message;
+
+        List<OnlineAccountData> peersOnlineAccounts = onlineAccountsMessage.getOnlineAccounts();
+        LOGGER.trace("Received {} online accounts from {}", peersOnlineAccounts.size(), peer);
+
+        int importCount = 0;
+
+        // Add any online accounts to the queue that aren't already present
+        for (OnlineAccountData onlineAccountData : peersOnlineAccounts) {
+
+            Set<OnlineAccountData> onlineAccounts = this.currentOnlineAccounts.computeIfAbsent(onlineAccountData.getTimestamp(), k -> ConcurrentHashMap.newKeySet());
+            if (onlineAccounts.contains(onlineAccountData))
+                // We have already validated this online account
+                continue;
+
+            boolean isNewEntry = onlineAccountsImportQueue.add(onlineAccountData);
+
+            if (isNewEntry)
+                importCount++;
+        }
+
+        if (importCount > 0)
+            LOGGER.debug("Added {} online accounts to queue", importCount);
     }
 }

src/main/java/org/qortal/controller/PirateChainWalletController.java

@@ -4,6 +4,7 @@ import com.rust.litewalletjni.LiteWalletJni;
 import org.apache.commons.io.FileUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.json.JSONException;
 import org.json.JSONObject;
 import org.qortal.arbitrary.ArbitraryDataFile;
 import org.qortal.arbitrary.ArbitraryDataReader;
@@ -99,14 +100,19 @@ public class PirateChainWalletController extends Thread {
                 LOGGER.debug("Syncing Pirate Chain wallet...");
                 String response = LiteWalletJni.execute("sync", "");
                 LOGGER.debug("sync response: {}", response);
-                JSONObject json = new JSONObject(response);
-                if (json.has("result")) {
-                    String result = json.getString("result");
 
-                    // We may have to set wallet to ready if this is the first ever successful sync
-                    if (Objects.equals(result, "success")) {
-                        this.currentWallet.setReady(true);
+                try {
+                    JSONObject json = new JSONObject(response);
+                    if (json.has("result")) {
+                        String result = json.getString("result");
+
+                        // We may have to set wallet to ready if this is the first ever successful sync
+                        if (Objects.equals(result, "success")) {
+                            this.currentWallet.setReady(true);
+                        }
                     }
+                } catch (JSONException e) {
+                    LOGGER.info("Unable to interpret JSON", e);
                 }
 
                 // Rate limit sync attempts
@@ -238,10 +244,10 @@ public class PirateChainWalletController extends Thread {
         if (osName.equals("Mac OS X") && osArchitecture.equals("x86_64")) {
             return "librust-macos-x86_64.dylib";
         }
-        else if (osName.equals("Linux") && osArchitecture.equals("aarch64")) {
+        else if ((osName.equals("Linux") || osName.equals("FreeBSD")) && osArchitecture.equals("aarch64")) {
             return "librust-linux-aarch64.so";
         }
-        else if (osName.equals("Linux") && osArchitecture.equals("amd64")) {
+        else if ((osName.equals("Linux") || osName.equals("FreeBSD")) && osArchitecture.equals("amd64")) {
             return "librust-linux-x86_64.so";
         }
         else if (osName.contains("Windows") && osArchitecture.equals("amd64")) {

src/main/java/org/qortal/controller/Synchronizer.java

@@ -19,7 +19,6 @@ import org.qortal.block.BlockChain;
 import org.qortal.data.block.BlockData;
 import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.block.CommonBlockData;
-import org.qortal.data.network.PeerChainTipData;
 import org.qortal.data.transaction.RewardShareTransactionData;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.event.Event;
@@ -54,7 +53,8 @@ public class Synchronizer extends Thread {
 	/** Maximum number of block signatures we ask from peer in one go */
 	private static final int MAXIMUM_REQUEST_SIZE = 200; // XXX move to Settings?
 
-	private static final long RECOVERY_MODE_TIMEOUT = 10 * 60 * 1000L; // ms
+	/** Maximum number of consecutive failed sync attempts before marking peer as misbehaved */
+	private static final int MAX_CONSECUTIVE_FAILED_SYNC_ATTEMPTS = 3;
 
 
 	private boolean running;
@@ -76,6 +76,8 @@ public class Synchronizer extends Thread {
 	private volatile boolean isSynchronizing = false;
 	/** Temporary estimate of synchronization progress for SysTray use. */
 	private volatile int syncPercent = 0;
+	/** Temporary estimate of blocks remaining for SysTray use. */
+	private volatile int blocksRemaining = 0;
 
 	private static volatile boolean requestSync = false;
 	private boolean syncRequestPending = false;
@@ -181,6 +183,18 @@ public class Synchronizer extends Thread {
 		}
 	}
 
+	public Integer getBlocksRemaining() {
+		synchronized (this.syncLock) {
+			// Report as 0 blocks remaining if the latest block is within the last 60 mins
+			final Long minLatestBlockTimestamp = NTP.getTime() - (60 * 60 * 1000L);
+			if (Controller.getInstance().isUpToDate(minLatestBlockTimestamp)) {
+				return 0;
+			}
+
+			return this.isSynchronizing ? this.blocksRemaining : null;
+		}
+	}
+
 	public void requestSync() {
 		requestSync = true;
 	}
@@ -233,6 +247,9 @@ public class Synchronizer extends Thread {
 		// Disregard peers that are on the same block as last sync attempt and we didn't like their chain
 		peers.removeIf(Controller.hasInferiorChainTip);
 
+		// Disregard peers that have a block with an invalid signer
+		peers.removeIf(Controller.hasInvalidSigner);
+
 		final int peersBeforeComparison = peers.size();
 
 		// Request recent block summaries from the remaining peers, and locate our common block with each
@@ -282,7 +299,7 @@ public class Synchronizer extends Thread {
 		BlockData priorChainTip = Controller.getInstance().getChainTip();
 
 		synchronized (this.syncLock) {
-			this.syncPercent = (priorChainTip.getHeight() * 100) / peer.getChainTipData().getLastHeight();
+			this.syncPercent = (priorChainTip.getHeight() * 100) / peer.getChainTipData().getHeight();
 
 			// Only update SysTray if we're potentially changing height
 			if (this.syncPercent < 100) {
@@ -312,7 +329,7 @@ public class Synchronizer extends Thread {
 
 				case INFERIOR_CHAIN: {
 					// Update our list of inferior chain tips
-					ByteArray inferiorChainSignature = ByteArray.wrap(peer.getChainTipData().getLastBlockSignature());
+					ByteArray inferiorChainSignature = ByteArray.wrap(peer.getChainTipData().getSignature());
 					if (!inferiorChainSignatures.contains(inferiorChainSignature))
 						inferiorChainSignatures.add(inferiorChainSignature);
 
@@ -320,7 +337,8 @@ public class Synchronizer extends Thread {
 					LOGGER.debug(() -> String.format("Refused to synchronize with peer %s (%s)", peer, syncResult.name()));
 
 					// Notify peer of our superior chain
-					if (!peer.sendMessage(Network.getInstance().buildHeightMessage(peer, priorChainTip)))
+					Message message = Network.getInstance().buildHeightOrChainTipInfo(peer);
+					if (message == null || !peer.sendMessage(message))
 						peer.disconnect("failed to notify peer of our superior chain");
 					break;
 				}
@@ -341,7 +359,7 @@ public class Synchronizer extends Thread {
 					// fall-through...
 				case NOTHING_TO_DO: {
 					// Update our list of inferior chain tips
-					ByteArray inferiorChainSignature = ByteArray.wrap(peer.getChainTipData().getLastBlockSignature());
+					ByteArray inferiorChainSignature = ByteArray.wrap(peer.getChainTipData().getSignature());
 					if (!inferiorChainSignatures.contains(inferiorChainSignature))
 						inferiorChainSignatures.add(inferiorChainSignature);
 
@@ -369,8 +387,7 @@ public class Synchronizer extends Thread {
 				// Reset our cache of inferior chains
 				inferiorChainSignatures.clear();
 
-				Network network = Network.getInstance();
-				network.broadcast(broadcastPeer -> network.buildHeightMessage(broadcastPeer, newChainTip));
+				Network.getInstance().broadcastOurChain();
 
 				EventBus.INSTANCE.notify(new NewChainTipEvent(priorChainTip, newChainTip));
 			}
@@ -397,9 +414,10 @@ public class Synchronizer extends Thread {
 					timePeersLastAvailable = NTP.getTime();
 
 				// If enough time has passed, enter recovery mode, which lifts some restrictions on who we can sync with and when we can mint
-				if (NTP.getTime() - timePeersLastAvailable > RECOVERY_MODE_TIMEOUT) {
+				long recoveryModeTimeout = Settings.getInstance().getRecoveryModeTimeout();
+				if (NTP.getTime() - timePeersLastAvailable > recoveryModeTimeout) {
 					if (recoveryMode == false) {
-						LOGGER.info(String.format("Peers have been unavailable for %d minutes. Entering recovery mode...", RECOVERY_MODE_TIMEOUT/60/1000));
+						LOGGER.info(String.format("Peers have been unavailable for %d minutes. Entering recovery mode...", recoveryModeTimeout/60/1000));
 						recoveryMode = true;
 					}
 				}
@@ -513,13 +531,13 @@ public class Synchronizer extends Thread {
 			final BlockData ourLatestBlockData = repository.getBlockRepository().getLastBlock();
 			final int ourInitialHeight = ourLatestBlockData.getHeight();
 
-			PeerChainTipData peerChainTipData = peer.getChainTipData();
-			int peerHeight = peerChainTipData.getLastHeight();
-			byte[] peersLastBlockSignature = peerChainTipData.getLastBlockSignature();
+			BlockSummaryData peerChainTipData = peer.getChainTipData();
+			int peerHeight = peerChainTipData.getHeight();
+			byte[] peersLastBlockSignature = peerChainTipData.getSignature();
 
 			byte[] ourLastBlockSignature = ourLatestBlockData.getSignature();
 			LOGGER.debug(String.format("Fetching summaries from peer %s at height %d, sig %.8s, ts %d; our height %d, sig %.8s, ts %d", peer,
-					peerHeight, Base58.encode(peersLastBlockSignature), peer.getChainTipData().getLastBlockTimestamp(),
+					peerHeight, Base58.encode(peersLastBlockSignature), peerChainTipData.getTimestamp(),
 					ourInitialHeight, Base58.encode(ourLastBlockSignature), ourLatestBlockData.getTimestamp()));
 
 			List<BlockSummaryData> peerBlockSummaries = new ArrayList<>();
@@ -637,9 +655,9 @@ public class Synchronizer extends Thread {
 							return peers;
 
 						// Count the number of blocks this peer has beyond our common block
-						final PeerChainTipData peerChainTipData = peer.getChainTipData();
-						final int peerHeight = peerChainTipData.getLastHeight();
-						final byte[] peerLastBlockSignature = peerChainTipData.getLastBlockSignature();
+						final BlockSummaryData peerChainTipData = peer.getChainTipData();
+						final int peerHeight = peerChainTipData.getHeight();
+						final byte[] peerLastBlockSignature = peerChainTipData.getSignature();
 						final int peerAdditionalBlocksAfterCommonBlock = peerHeight - commonBlockSummary.getHeight();
 						// Limit the number of blocks we are comparing. FUTURE: we could request more in batches, but there may not be a case when this is needed
 						int summariesRequired = Math.min(peerAdditionalBlocksAfterCommonBlock, MAXIMUM_REQUEST_SIZE);
@@ -727,8 +745,9 @@ public class Synchronizer extends Thread {
 
 					LOGGER.debug(String.format("Listing peers with common block %.8s...", Base58.encode(commonBlockSummary.getSignature())));
 					for (Peer peer : peersSharingCommonBlock) {
-						final int peerHeight = peer.getChainTipData().getLastHeight();
-						final Long peerLastBlockTimestamp = peer.getChainTipData().getLastBlockTimestamp();
+						BlockSummaryData peerChainTipData = peer.getChainTipData();
+						final int peerHeight = peerChainTipData.getHeight();
+						final Long peerLastBlockTimestamp = peerChainTipData.getTimestamp();
 						final int peerAdditionalBlocksAfterCommonBlock = peerHeight - commonBlockSummary.getHeight();
 						final CommonBlockData peerCommonBlockData = peer.getCommonBlockData();
 
@@ -825,7 +844,7 @@ public class Synchronizer extends Thread {
 		// Calculate the length of the shortest peer chain sharing this common block
 		int minChainLength = 0;
 		for (Peer peer : peersSharingCommonBlock) {
-			final int peerHeight = peer.getChainTipData().getLastHeight();
+			final int peerHeight = peer.getChainTipData().getHeight();
 			final int peerAdditionalBlocksAfterCommonBlock = peerHeight - commonBlockSummary.getHeight();
 
 			if (peerAdditionalBlocksAfterCommonBlock < minChainLength || minChainLength == 0)
@@ -933,13 +952,13 @@ public class Synchronizer extends Thread {
 					final BlockData ourLatestBlockData = repository.getBlockRepository().getLastBlock();
 					final int ourInitialHeight = ourLatestBlockData.getHeight();
 
-					PeerChainTipData peerChainTipData = peer.getChainTipData();
-					int peerHeight = peerChainTipData.getLastHeight();
-					byte[] peersLastBlockSignature = peerChainTipData.getLastBlockSignature();
+					BlockSummaryData peerChainTipData = peer.getChainTipData();
+					int peerHeight = peerChainTipData.getHeight();
+					byte[] peersLastBlockSignature = peerChainTipData.getSignature();
 
 					byte[] ourLastBlockSignature = ourLatestBlockData.getSignature();
 					String syncString = String.format("Synchronizing with peer %s at height %d, sig %.8s, ts %d; our height %d, sig %.8s, ts %d", peer,
-							peerHeight, Base58.encode(peersLastBlockSignature), peer.getChainTipData().getLastBlockTimestamp(),
+							peerHeight, Base58.encode(peersLastBlockSignature), peerChainTipData.getTimestamp(),
 							ourInitialHeight, Base58.encode(ourLastBlockSignature), ourLatestBlockData.getTimestamp());
 					LOGGER.info(syncString);
 
@@ -1102,6 +1121,7 @@ public class Synchronizer extends Thread {
 			// If common block is too far behind us then we're on massively different forks so give up.
 			if (!force && testHeight < ourHeight - MAXIMUM_COMMON_DELTA) {
 				LOGGER.info(String.format("Blockchain too divergent with peer %s", peer));
+				peer.setLastTooDivergentTime(NTP.getTime());
 				return SynchronizationResult.TOO_DIVERGENT;
 			}
 
@@ -1111,6 +1131,9 @@ public class Synchronizer extends Thread {
 			testHeight = Math.max(testHeight - step, 1);
 		}
 
+		// Peer not considered too divergent
+		peer.setLastTooDivergentTime(0L);
+
 		// Prepend test block's summary as first block summary, as summaries returned are *after* test block
 		BlockSummaryData testBlockSummary = new BlockSummaryData(testBlockData);
 		blockSummariesFromCommon.add(0, testBlockSummary);
@@ -1246,7 +1269,14 @@ public class Synchronizer extends Thread {
 		int numberSignaturesRequired = additionalPeerBlocksAfterCommonBlock - peerBlockSignatures.size();
 
 		int retryCount = 0;
-		while (height < peerHeight) {
+
+		// Keep fetching blocks from peer until we reach their tip, or reach a count of MAXIMUM_COMMON_DELTA blocks.
+		// We need to limit the total number, otherwise too much can be loaded into memory, causing an
+		// OutOfMemoryException. This is common when syncing from 1000+ blocks behind the chain tip, after starting
+		// from a small fork that didn't become part of the main chain. This causes the entire sync process to
+		// use syncToPeerChain(), resulting in potentially thousands of blocks being held in memory if the limit
+		// below isn't applied.
+		while (height < peerHeight && peerBlocks.size() <= MAXIMUM_COMMON_DELTA) {
 			if (Controller.isStopping())
 				return SynchronizationResult.SHUTTING_DOWN;
 
@@ -1313,7 +1343,7 @@ public class Synchronizer extends Thread {
 			// Final check to make sure the peer isn't out of date (except for when we're in recovery mode)
 			if (!recoveryMode && peer.getChainTipData() != null) {
 				final Long minLatestBlockTimestamp = Controller.getMinimumLatestBlockTimestamp();
-				final Long peerLastBlockTimestamp = peer.getChainTipData().getLastBlockTimestamp();
+				final Long peerLastBlockTimestamp = peer.getChainTipData().getTimestamp();
 				if (peerLastBlockTimestamp == null || peerLastBlockTimestamp < minLatestBlockTimestamp) {
 					LOGGER.info(String.format("Peer %s is out of date, so abandoning sync attempt", peer));
 					return SynchronizationResult.CHAIN_TIP_TOO_OLD;
@@ -1448,6 +1478,12 @@ public class Synchronizer extends Thread {
 
 			repository.saveChanges();
 
+			synchronized (this.syncLock) {
+				if (peer.getChainTipData() != null) {
+					this.blocksRemaining = peer.getChainTipData().getHeight() - newBlock.getBlockData().getHeight();
+				}
+			}
+
 			Controller.getInstance().onNewBlock(newBlock.getBlockData());
 		}
 
@@ -1543,6 +1579,12 @@ public class Synchronizer extends Thread {
 
 			repository.saveChanges();
 
+			synchronized (this.syncLock) {
+				if (peer.getChainTipData() != null) {
+					this.blocksRemaining = peer.getChainTipData().getHeight() - newBlock.getBlockData().getHeight();
+				}
+			}
+
 			Controller.getInstance().onNewBlock(newBlock.getBlockData());
 		}
 
@@ -1553,12 +1595,19 @@ public class Synchronizer extends Thread {
 		Message getBlockSummariesMessage = new GetBlockSummariesMessage(parentSignature, numberRequested);
 
 		Message message = peer.getResponse(getBlockSummariesMessage);
-		if (message == null || message.getType() != MessageType.BLOCK_SUMMARIES)
+		if (message == null)
 			return null;
 
-		BlockSummariesMessage blockSummariesMessage = (BlockSummariesMessage) message;
+		if (message.getType() == MessageType.BLOCK_SUMMARIES) {
+			BlockSummariesMessage blockSummariesMessage = (BlockSummariesMessage) message;
+			return blockSummariesMessage.getBlockSummaries();
+		}
+		else if (message.getType() == MessageType.BLOCK_SUMMARIES_V2) {
+			BlockSummariesV2Message blockSummariesMessage = (BlockSummariesV2Message) message;
+			return blockSummariesMessage.getBlockSummaries();
+		}
 
-		return blockSummariesMessage.getBlockSummaries();
+		return null;
 	}
 
 	private List<byte[]> getBlockSignatures(Peer peer, byte[] parentSignature, int numberRequested) throws InterruptedException {
@@ -1577,8 +1626,20 @@ public class Synchronizer extends Thread {
 		Message getBlockMessage = new GetBlockMessage(signature);
 
 		Message message = peer.getResponse(getBlockMessage);
-		if (message == null)
+		if (message == null) {
+			peer.getPeerData().incrementFailedSyncCount();
+			if (peer.getPeerData().getFailedSyncCount() >= MAX_CONSECUTIVE_FAILED_SYNC_ATTEMPTS) {
+				// Several failed attempts, so mark peer as misbehaved
+				LOGGER.info("Marking peer {} as misbehaved due to {} failed sync attempts", peer, peer.getPeerData().getFailedSyncCount());
+				Network.getInstance().peerMisbehaved(peer);
+			}
 			return null;
+		}
+
+		// Reset failed sync count now that we have a block response
+		// FUTURE: we could move this to the end of the sync process, but to reduce risk this can be done
+		// at a later stage. For now we are only defending against serialization errors or no responses.
+		peer.getPeerData().setFailedSyncCount(0);
 
 		switch (message.getType()) {
 			case BLOCK: {

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataFileManager.java

@@ -82,7 +82,7 @@ public class ArbitraryDataFileManager extends Thread {
 
         try {
             // Use a fixed thread pool to execute the arbitrary data file requests
-            int threadCount = 10;
+            int threadCount = 5;
             ExecutorService arbitraryDataFileRequestExecutor = Executors.newFixedThreadPool(threadCount);
             for (int i = 0; i < threadCount; i++) {
                 arbitraryDataFileRequestExecutor.execute(new ArbitraryDataFileRequestThread());
@@ -288,7 +288,7 @@ public class ArbitraryDataFileManager extends Thread {
         // The ID needs to match that of the original request
         message.setId(originalMessage.getId());
 
-        if (!requestingPeer.sendMessage(message)) {
+        if (!requestingPeer.sendMessageWithTimeout(message, (int) ArbitraryDataManager.ARBITRARY_REQUEST_TIMEOUT)) {
             LOGGER.debug("Failed to forward arbitrary data file to peer {}", requestingPeer);
             requestingPeer.disconnect("failed to forward arbitrary data file");
         }
@@ -564,13 +564,16 @@ public class ArbitraryDataFileManager extends Thread {
                 LOGGER.trace("Hash {} exists", hash58);
 
                 // We can serve the file directly as we already have it
+                LOGGER.debug("Sending file {}...", arbitraryDataFile);
                 ArbitraryDataFileMessage arbitraryDataFileMessage = new ArbitraryDataFileMessage(signature, arbitraryDataFile);
                 arbitraryDataFileMessage.setId(message.getId());
-                if (!peer.sendMessage(arbitraryDataFileMessage)) {
-                    LOGGER.debug("Couldn't sent file");
+                if (!peer.sendMessageWithTimeout(arbitraryDataFileMessage, (int) ArbitraryDataManager.ARBITRARY_REQUEST_TIMEOUT)) {
+                    LOGGER.debug("Couldn't send file {}", arbitraryDataFile);
                     peer.disconnect("failed to send file");
                 }
-                LOGGER.debug("Sent file {}", arbitraryDataFile);
+                else {
+                    LOGGER.debug("Sent file {}", arbitraryDataFile);
+                }
             }
             else if (relayInfo != null) {
                 LOGGER.debug("We have relay info for hash {}", Base58.encode(hash));
@@ -595,9 +598,10 @@ public class ArbitraryDataFileManager extends Thread {
                 // Send valid, yet unexpected message type in response, so peer's synchronizer doesn't have to wait for timeout
                 LOGGER.debug(String.format("Sending 'file unknown' response to peer %s for GET_FILE request for unknown file %s", peer, arbitraryDataFile));
 
-                // We'll send empty block summaries message as it's very short
-                // TODO: use a different message type here
-                Message fileUnknownMessage = new BlockSummariesMessage(Collections.emptyList());
+                // Send generic 'unknown' message as it's very short
+                Message fileUnknownMessage = peer.getPeersVersion() >= GenericUnknownMessage.MINIMUM_PEER_VERSION
+                        ? new GenericUnknownMessage()
+                        : new BlockSummariesMessage(Collections.emptyList());
                 fileUnknownMessage.setId(message.getId());
                 if (!peer.sendMessage(fileUnknownMessage)) {
                     LOGGER.debug("Couldn't sent file-unknown response");

src/main/java/org/qortal/controller/repository/AtStatesPruner.java

@@ -42,6 +42,7 @@ public class AtStatesPruner implements Runnable {
 
 			repository.discardChanges();
 			repository.getATRepository().rebuildLatestAtStates();
+			repository.saveChanges();
 
 			while (!Controller.isStopping()) {
 				repository.discardChanges();

src/main/java/org/qortal/controller/repository/AtStatesTrimmer.java

@@ -29,6 +29,7 @@ public class AtStatesTrimmer implements Runnable {
 
 			repository.discardChanges();
 			repository.getATRepository().rebuildLatestAtStates();
+			repository.saveChanges();
 
 			while (!Controller.isStopping()) {
 				repository.discardChanges();

src/main/java/org/qortal/controller/repository/BlockArchiver.java

@@ -16,7 +16,7 @@ public class BlockArchiver implements Runnable {
 
 	private static final Logger LOGGER = LogManager.getLogger(BlockArchiver.class);
 
-	private static final long INITIAL_SLEEP_PERIOD = 0L; // TODO: 5 * 60 * 1000L + 1234L; // ms
+	private static final long INITIAL_SLEEP_PERIOD = 5 * 60 * 1000L + 1234L; // ms
 
 	public void run() {
 		Thread.currentThread().setName("Block archiver");

src/main/java/org/qortal/controller/tradebot/DogecoinACCTv2TradeBot.java

@@ -1,884 +0,0 @@
-package org.qortal.controller.tradebot;
-
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
-import org.bitcoinj.core.*;
-import org.bitcoinj.script.Script.ScriptType;
-import org.qortal.account.PrivateKeyAccount;
-import org.qortal.account.PublicKeyAccount;
-import org.qortal.api.model.crosschain.TradeBotCreateRequest;
-import org.qortal.asset.Asset;
-import org.qortal.crosschain.*;
-import org.qortal.crypto.Crypto;
-import org.qortal.data.at.ATData;
-import org.qortal.data.crosschain.CrossChainTradeData;
-import org.qortal.data.crosschain.TradeBotData;
-import org.qortal.data.transaction.BaseTransactionData;
-import org.qortal.data.transaction.DeployAtTransactionData;
-import org.qortal.data.transaction.MessageTransactionData;
-import org.qortal.group.Group;
-import org.qortal.repository.DataException;
-import org.qortal.repository.Repository;
-import org.qortal.transaction.DeployAtTransaction;
-import org.qortal.transaction.MessageTransaction;
-import org.qortal.transaction.Transaction.ValidationResult;
-import org.qortal.transform.TransformationException;
-import org.qortal.transform.transaction.DeployAtTransactionTransformer;
-import org.qortal.utils.Base58;
-import org.qortal.utils.NTP;
-
-import java.util.Arrays;
-import java.util.List;
-import java.util.Map;
-import java.util.stream.Collectors;
-
-import static java.util.Arrays.stream;
-import static java.util.stream.Collectors.toMap;
-
-/**
- * Performing cross-chain trading steps on behalf of user.
- * <p>
- * We deal with three different independent state-spaces here:
- * <ul>
- * 	<li>Qortal blockchain</li>
- * 	<li>Foreign blockchain</li>
- * 	<li>Trade-bot entries</li>
- * </ul>
- */
-public class DogecoinACCTv2TradeBot implements AcctTradeBot {
-
-	private static final Logger LOGGER = LogManager.getLogger(DogecoinACCTv2TradeBot.class);
-
-	public enum State implements TradeBot.StateNameAndValueSupplier {
-		BOB_WAITING_FOR_AT_CONFIRM(10, false, false),
-		BOB_WAITING_FOR_MESSAGE(15, true, true),
-		BOB_WAITING_FOR_AT_REDEEM(25, true, true),
-		BOB_DONE(30, false, false),
-		BOB_REFUNDED(35, false, false),
-
-		ALICE_WAITING_FOR_AT_LOCK(85, true, true),
-		ALICE_DONE(95, false, false),
-		ALICE_REFUNDING_A(105, true, true),
-		ALICE_REFUNDED(110, false, false);
-
-		private static final Map<Integer, State> map = stream(State.values()).collect(toMap(state -> state.value, state -> state));
-
-		public final int value;
-		public final boolean requiresAtData;
-		public final boolean requiresTradeData;
-
-		State(int value, boolean requiresAtData, boolean requiresTradeData) {
-			this.value = value;
-			this.requiresAtData = requiresAtData;
-			this.requiresTradeData = requiresTradeData;
-		}
-
-		public static State valueOf(int value) {
-			return map.get(value);
-		}
-
-		@Override
-		public String getState() {
-			return this.name();
-		}
-
-		@Override
-		public int getStateValue() {
-			return this.value;
-		}
-	}
-
-	/** Maximum time Bob waits for his AT creation transaction to be confirmed into a block. (milliseconds) */
-	private static final long MAX_AT_CONFIRMATION_PERIOD = 24 * 60 * 60 * 1000L; // ms
-
-	private static DogecoinACCTv2TradeBot instance;
-
-	private final List<String> endStates = Arrays.asList(State.BOB_DONE, State.BOB_REFUNDED, State.ALICE_DONE, State.ALICE_REFUNDING_A, State.ALICE_REFUNDED).stream()
-			.map(State::name)
-			.collect(Collectors.toUnmodifiableList());
-
-	private DogecoinACCTv2TradeBot() {
-	}
-
-	public static synchronized DogecoinACCTv2TradeBot getInstance() {
-		if (instance == null)
-			instance = new DogecoinACCTv2TradeBot();
-
-		return instance;
-	}
-
-	@Override
-	public List<String> getEndStates() {
-		return this.endStates;
-	}
-
-	/**
-	 * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for DOGE.
-	 * <p>
-	 * Generates:
-	 * <ul>
-	 * 	<li>new 'trade' private key</li>
-	 * </ul>
-	 * Derives:
-	 * <ul>
-	 * 	<li>'native' (as in Qortal) public key, public key hash, address (starting with Q)</li>
-	 * 	<li>'foreign' (as in Dogecoin) public key, public key hash</li>
-	 * </ul>
-	 * A Qortal AT is then constructed including the following as constants in the 'data segment':
-	 * <ul>
-	 * 	<li>'native'/Qortal 'trade' address - used as a MESSAGE contact</li>
-	 * 	<li>'foreign'/Dogecoin public key hash - used by Alice's P2SH scripts to allow redeem</li>
-	 * 	<li>QORT amount on offer by Bob</li>
-	 * 	<li>DOGE amount expected in return by Bob (from Alice)</li>
-	 * 	<li>trading timeout, in case things go wrong and everyone needs to refund</li>
-	 * </ul>
-	 * Returns a DEPLOY_AT transaction that needs to be signed and broadcast to the Qortal network.
-	 * <p>
-	 * Trade-bot will wait for Bob's AT to be deployed before taking next step.
-	 * <p>
-	 * @param repository
-	 * @param tradeBotCreateRequest
-	 * @return raw, unsigned DEPLOY_AT transaction
-	 * @throws DataException
-	 */
-	public byte[] createTrade(Repository repository, TradeBotCreateRequest tradeBotCreateRequest) throws DataException {
-		byte[] tradePrivateKey = TradeBot.generateTradePrivateKey();
-
-		byte[] tradeNativePublicKey = TradeBot.deriveTradeNativePublicKey(tradePrivateKey);
-		byte[] tradeNativePublicKeyHash = Crypto.hash160(tradeNativePublicKey);
-		String tradeNativeAddress = Crypto.toAddress(tradeNativePublicKey);
-
-		byte[] tradeForeignPublicKey = TradeBot.deriveTradeForeignPublicKey(tradePrivateKey);
-		byte[] tradeForeignPublicKeyHash = Crypto.hash160(tradeForeignPublicKey);
-
-		// Convert Dogecoin receiving address into public key hash (we only support P2PKH at this time)
-		Address dogecoinReceivingAddress;
-		try {
-			dogecoinReceivingAddress = Address.fromString(Dogecoin.getInstance().getNetworkParameters(), tradeBotCreateRequest.receivingAddress);
-		} catch (AddressFormatException e) {
-			throw new DataException("Unsupported Dogecoin receiving address: " + tradeBotCreateRequest.receivingAddress);
-		}
-		if (dogecoinReceivingAddress.getOutputScriptType() != ScriptType.P2PKH)
-			throw new DataException("Unsupported Dogecoin receiving address: " + tradeBotCreateRequest.receivingAddress);
-
-		byte[] dogecoinReceivingAccountInfo = dogecoinReceivingAddress.getHash();
-
-		PublicKeyAccount creator = new PublicKeyAccount(repository, tradeBotCreateRequest.creatorPublicKey);
-
-		// Deploy AT
-		long timestamp = NTP.getTime();
-		byte[] reference = creator.getLastReference();
-		long fee = 0L;
-		byte[] signature = null;
-		BaseTransactionData baseTransactionData = new BaseTransactionData(timestamp, Group.NO_GROUP, reference, creator.getPublicKey(), fee, signature);
-
-		String name = "QORT/DOGE ACCT";
-		String description = "QORT/DOGE cross-chain trade";
-		String aTType = "ACCT";
-		String tags = "ACCT QORT DOGE";
-		byte[] creationBytes = DogecoinACCTv2.buildQortalAT(tradeNativeAddress, tradeForeignPublicKeyHash, tradeBotCreateRequest.qortAmount,
-				tradeBotCreateRequest.foreignAmount, tradeBotCreateRequest.tradeTimeout);
-		long amount = tradeBotCreateRequest.fundingQortAmount;
-
-		DeployAtTransactionData deployAtTransactionData = new DeployAtTransactionData(baseTransactionData, name, description, aTType, tags, creationBytes, amount, Asset.QORT);
-
-		DeployAtTransaction deployAtTransaction = new DeployAtTransaction(repository, deployAtTransactionData);
-		fee = deployAtTransaction.calcRecommendedFee();
-		deployAtTransactionData.setFee(fee);
-
-		DeployAtTransaction.ensureATAddress(deployAtTransactionData);
-		String atAddress = deployAtTransactionData.getAtAddress();
-
-		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, DogecoinACCTv2.NAME,
-				State.BOB_WAITING_FOR_AT_CONFIRM.name(), State.BOB_WAITING_FOR_AT_CONFIRM.value,
-				creator.getAddress(), atAddress, timestamp, tradeBotCreateRequest.qortAmount,
-				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
-				null, null,
-				SupportedBlockchain.DOGECOIN.name(),
-				tradeForeignPublicKey, tradeForeignPublicKeyHash,
-				tradeBotCreateRequest.foreignAmount, null, null, null, dogecoinReceivingAccountInfo);
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Built AT %s. Waiting for deployment", atAddress));
-
-		// Attempt to backup the trade bot data
-		TradeBot.backupTradeBotData(repository, null);
-
-		// Return to user for signing and broadcast as we don't have their Qortal private key
-		try {
-			return DeployAtTransactionTransformer.toBytes(deployAtTransactionData);
-		} catch (TransformationException e) {
-			throw new DataException("Failed to transform DEPLOY_AT transaction?", e);
-		}
-	}
-
-	/**
-	 * Creates a trade-bot entry from the 'Alice' viewpoint, i.e. matching DOGE to an existing offer.
-	 * <p>
-	 * Requires a chosen trade offer from Bob, passed by <tt>crossChainTradeData</tt>
-	 * and access to a Dogecoin wallet via <tt>xprv58</tt>.
-	 * <p>
-	 * The <tt>crossChainTradeData</tt> contains the current trade offer state
-	 * as extracted from the AT's data segment.
-	 * <p>
-	 * Access to a funded wallet is via a Dogecoin BIP32 hierarchical deterministic key,
-	 * passed via <tt>xprv58</tt>.
-	 * <b>This key will be stored in your node's database</b>
-	 * to allow trade-bot to create/fund the necessary P2SH transactions!
-	 * However, due to the nature of BIP32 keys, it is possible to give the trade-bot
-	 * only a subset of wallet access (see BIP32 for more details).
-	 * <p>
-	 * As an example, the xprv58 can be extract from a <i>legacy, password-less</i>
-	 * Electrum wallet by going to the console tab and entering:<br>
-	 * <tt>wallet.keystore.xprv</tt><br>
-	 * which should result in a base58 string starting with either 'xprv' (for Dogecoin main-net)
-	 * or 'tprv' for (Dogecoin test-net).
-	 * <p>
-	 * It is envisaged that the value in <tt>xprv58</tt> will actually come from a Qortal-UI-managed wallet.
-	 * <p>
-	 * If sufficient funds are available, <b>this method will actually fund the P2SH-A</b>
-	 * with the Dogecoin amount expected by 'Bob'.
-	 * <p>
-	 * If the Dogecoin transaction is successfully broadcast to the network then
-	 * we also send a MESSAGE to Bob's trade-bot to let them know.
-	 * <p>
-	 * The trade-bot entry is saved to the repository and the cross-chain trading process commences.
-	 * <p>
-	 * @param repository
-	 * @param crossChainTradeData chosen trade OFFER that Alice wants to match
-	 * @param xprv58 funded wallet xprv in base58
-	 * @return true if P2SH-A funding transaction successfully broadcast to Dogecoin network, false otherwise
-	 * @throws DataException
-	 */
-	public ResponseResult startResponse(Repository repository, ATData atData, ACCT acct, CrossChainTradeData crossChainTradeData, String xprv58, String receivingAddress) throws DataException {
-		byte[] tradePrivateKey = TradeBot.generateTradePrivateKey();
-		byte[] secretA = TradeBot.generateSecret();
-		byte[] hashOfSecretA = Crypto.hash160(secretA);
-
-		byte[] tradeNativePublicKey = TradeBot.deriveTradeNativePublicKey(tradePrivateKey);
-		byte[] tradeNativePublicKeyHash = Crypto.hash160(tradeNativePublicKey);
-		String tradeNativeAddress = Crypto.toAddress(tradeNativePublicKey);
-
-		byte[] tradeForeignPublicKey = TradeBot.deriveTradeForeignPublicKey(tradePrivateKey);
-		byte[] tradeForeignPublicKeyHash = Crypto.hash160(tradeForeignPublicKey);
-		byte[] receivingPublicKeyHash = Base58.decode(receivingAddress); // Actually the whole address, not just PKH
-
-		// We need to generate lockTime-A: add tradeTimeout to now
-		long now = NTP.getTime();
-		int lockTimeA = crossChainTradeData.tradeTimeout * 60 + (int) (now / 1000L);
-
-		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, DogecoinACCTv2.NAME,
-				State.ALICE_WAITING_FOR_AT_LOCK.name(), State.ALICE_WAITING_FOR_AT_LOCK.value,
-				receivingAddress, crossChainTradeData.qortalAtAddress, now, crossChainTradeData.qortAmount,
-				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
-				secretA, hashOfSecretA,
-				SupportedBlockchain.DOGECOIN.name(),
-				tradeForeignPublicKey, tradeForeignPublicKeyHash,
-				crossChainTradeData.expectedForeignAmount, xprv58, null, lockTimeA, receivingPublicKeyHash);
-
-		// Attempt to backup the trade bot data
-		// Include tradeBotData as an additional parameter, since it's not in the repository yet
-		TradeBot.backupTradeBotData(repository, Arrays.asList(tradeBotData));
-
-		// Check we have enough funds via xprv58 to fund P2SH to cover expectedForeignAmount
-		long p2shFee;
-		try {
-			p2shFee = Dogecoin.getInstance().getP2shFee(now);
-		} catch (ForeignBlockchainException e) {
-			LOGGER.debug("Couldn't estimate Dogecoin fees?");
-			return ResponseResult.NETWORK_ISSUE;
-		}
-
-		// Fee for redeem/refund is subtracted from P2SH-A balance.
-		// Do not include fee for funding transaction as this is covered by buildSpend()
-		long amountA = crossChainTradeData.expectedForeignAmount + p2shFee /*redeeming/refunding P2SH-A*/;
-
-		// P2SH-A to be funded
-		byte[] redeemScriptBytes = BitcoinyHTLC.buildScript(tradeForeignPublicKeyHash, lockTimeA, crossChainTradeData.creatorForeignPKH, hashOfSecretA);
-		String p2shAddress = Dogecoin.getInstance().deriveP2shAddress(redeemScriptBytes);
-
-		// Build transaction for funding P2SH-A
-		Transaction p2shFundingTransaction = Dogecoin.getInstance().buildSpend(tradeBotData.getForeignKey(), p2shAddress, amountA);
-		if (p2shFundingTransaction == null) {
-			LOGGER.debug("Unable to build P2SH-A funding transaction - lack of funds?");
-			return ResponseResult.BALANCE_ISSUE;
-		}
-
-		try {
-			Dogecoin.getInstance().broadcastTransaction(p2shFundingTransaction);
-		} catch (ForeignBlockchainException e) {
-			// We couldn't fund P2SH-A at this time
-			LOGGER.debug("Couldn't broadcast P2SH-A funding transaction?");
-			return ResponseResult.NETWORK_ISSUE;
-		}
-
-		// Attempt to send MESSAGE to Bob's Qortal trade address
-		byte[] messageData = DogecoinACCTv2.buildOfferMessage(tradeBotData.getTradeForeignPublicKeyHash(), tradeBotData.getHashOfSecret(), tradeBotData.getLockTimeA());
-		String messageRecipient = crossChainTradeData.qortalCreatorTradeAddress;
-
-		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
-		if (!isMessageAlreadySent) {
-			PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
-			MessageTransaction messageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, messageData, false, false);
-
-			messageTransaction.computeNonce();
-			messageTransaction.sign(sender);
-
-			// reset repository state to prevent deadlock
-			repository.discardChanges();
-			ValidationResult result = messageTransaction.importAsUnconfirmed();
-
-			if (result != ValidationResult.OK) {
-				LOGGER.warn(() -> String.format("Unable to send MESSAGE to Bob's trade-bot %s: %s", messageRecipient, result.name()));
-				return ResponseResult.NETWORK_ISSUE;
-			}
-		}
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Funding P2SH-A %s. Messaged Bob. Waiting for AT-lock", p2shAddress));
-
-		return ResponseResult.OK;
-	}
-
-	@Override
-	public boolean canDelete(Repository repository, TradeBotData tradeBotData) throws DataException {
-		State tradeBotState = State.valueOf(tradeBotData.getStateValue());
-		if (tradeBotState == null)
-			return true;
-
-		// If the AT doesn't exist then we might as well let the user tidy up
-		if (!repository.getATRepository().exists(tradeBotData.getAtAddress()))
-			return true;
-
-		switch (tradeBotState) {
-			case BOB_WAITING_FOR_AT_CONFIRM:
-			case ALICE_DONE:
-			case BOB_DONE:
-			case ALICE_REFUNDED:
-			case BOB_REFUNDED:
-				return true;
-
-			default:
-				return false;
-		}
-	}
-
-	@Override
-	public void progress(Repository repository, TradeBotData tradeBotData) throws DataException, ForeignBlockchainException {
-		State tradeBotState = State.valueOf(tradeBotData.getStateValue());
-		if (tradeBotState == null) {
-			LOGGER.info(() -> String.format("Trade-bot entry for AT %s has invalid state?", tradeBotData.getAtAddress()));
-			return;
-		}
-
-		ATData atData = null;
-		CrossChainTradeData tradeData = null;
-
-		if (tradeBotState.requiresAtData) {
-			// Attempt to fetch AT data
-			atData = repository.getATRepository().fromATAddress(tradeBotData.getAtAddress());
-			if (atData == null) {
-				LOGGER.debug(() -> String.format("Unable to fetch trade AT %s from repository", tradeBotData.getAtAddress()));
-				return;
-			}
-
-			if (tradeBotState.requiresTradeData) {
-				tradeData = DogecoinACCTv2.getInstance().populateTradeData(repository, atData);
-				if (tradeData == null) {
-					LOGGER.warn(() -> String.format("Unable to fetch ACCT trade data for AT %s from repository", tradeBotData.getAtAddress()));
-					return;
-				}
-			}
-		}
-
-		switch (tradeBotState) {
-			case BOB_WAITING_FOR_AT_CONFIRM:
-				handleBobWaitingForAtConfirm(repository, tradeBotData);
-				break;
-
-			case BOB_WAITING_FOR_MESSAGE:
-				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
-				handleBobWaitingForMessage(repository, tradeBotData, atData, tradeData);
-				break;
-
-			case ALICE_WAITING_FOR_AT_LOCK:
-				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
-				handleAliceWaitingForAtLock(repository, tradeBotData, atData, tradeData);
-				break;
-
-			case BOB_WAITING_FOR_AT_REDEEM:
-				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
-				handleBobWaitingForAtRedeem(repository, tradeBotData, atData, tradeData);
-				break;
-
-			case ALICE_DONE:
-			case BOB_DONE:
-				break;
-
-			case ALICE_REFUNDING_A:
-				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
-				handleAliceRefundingP2shA(repository, tradeBotData, atData, tradeData);
-				break;
-
-			case ALICE_REFUNDED:
-			case BOB_REFUNDED:
-				break;
-		}
-	}
-
-	/**
-	 * Trade-bot is waiting for Bob's AT to deploy.
-	 * <p>
-	 * If AT is deployed, then trade-bot's next step is to wait for MESSAGE from Alice.
-	 */
-	private void handleBobWaitingForAtConfirm(Repository repository, TradeBotData tradeBotData) throws DataException {
-		if (!repository.getATRepository().exists(tradeBotData.getAtAddress())) {
-			if (NTP.getTime() - tradeBotData.getTimestamp() <= MAX_AT_CONFIRMATION_PERIOD)
-				return;
-
-			// We've waited ages for AT to be confirmed into a block but something has gone awry.
-			// After this long we assume transaction loss so give up with trade-bot entry too.
-			tradeBotData.setState(State.BOB_REFUNDED.name());
-			tradeBotData.setStateValue(State.BOB_REFUNDED.value);
-			tradeBotData.setTimestamp(NTP.getTime());
-			// We delete trade-bot entry here instead of saving, hence not using updateTradeBotState()
-			repository.getCrossChainRepository().delete(tradeBotData.getTradePrivateKey());
-			repository.saveChanges();
-
-			LOGGER.info(() -> String.format("AT %s never confirmed. Giving up on trade", tradeBotData.getAtAddress()));
-			TradeBot.notifyStateChange(tradeBotData);
-			return;
-		}
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_WAITING_FOR_MESSAGE,
-				() -> String.format("AT %s confirmed ready. Waiting for trade message", tradeBotData.getAtAddress()));
-	}
-
-	/**
-	 * Trade-bot is waiting for MESSAGE from Alice's trade-bot, containing Alice's trade info.
-	 * <p>
-	 * It's possible Bob has cancelling his trade offer, receiving an automatic QORT refund,
-	 * in which case trade-bot is done with this specific trade and finalizes on refunded state.
-	 * <p>
-	 * Assuming trade is still on offer, trade-bot checks the contents of MESSAGE from Alice's trade-bot.
-	 * <p>
-	 * Details from Alice are used to derive P2SH-A address and this is checked for funding balance.
-	 * <p>
-	 * Assuming P2SH-A has at least expected Dogecoin balance,
-	 * Bob's trade-bot constructs a zero-fee, PoW MESSAGE to send to Bob's AT with more trade details.
-	 * <p>
-	 * On processing this MESSAGE, Bob's AT should switch into 'TRADE' mode and only trade with Alice.
-	 * <p>
-	 * Trade-bot's next step is to wait for Alice to redeem the AT, which will allow Bob to
-	 * extract secret-A needed to redeem Alice's P2SH.
-	 * @throws ForeignBlockchainException
-	 */
-	private void handleBobWaitingForMessage(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		// If AT has finished then Bob likely cancelled his trade offer
-		if (atData.getIsFinished()) {
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_REFUNDED,
-					() -> String.format("AT %s cancelled - trading aborted", tradeBotData.getAtAddress()));
-			return;
-		}
-
-		Dogecoin dogecoin = Dogecoin.getInstance();
-
-		String address = tradeBotData.getTradeNativeAddress();
-		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(null, address, null, null, null);
-
-		for (MessageTransactionData messageTransactionData : messageTransactionsData) {
-			if (messageTransactionData.isText())
-				continue;
-
-			// We're expecting: HASH160(secret-A), Alice's Dogecoin pubkeyhash and lockTime-A
-			byte[] messageData = messageTransactionData.getData();
-			DogecoinACCTv2.OfferMessageData offerMessageData = DogecoinACCTv2.extractOfferMessageData(messageData);
-			if (offerMessageData == null)
-				continue;
-
-			byte[] aliceForeignPublicKeyHash = offerMessageData.partnerDogecoinPKH;
-			byte[] hashOfSecretA = offerMessageData.hashOfSecretA;
-			int lockTimeA = (int) offerMessageData.lockTimeA;
-			long messageTimestamp = messageTransactionData.getTimestamp();
-			int refundTimeout = DogecoinACCTv2.calcRefundTimeout(messageTimestamp, lockTimeA);
-
-			// Determine P2SH-A address and confirm funded
-			byte[] redeemScriptA = BitcoinyHTLC.buildScript(aliceForeignPublicKeyHash, lockTimeA, tradeBotData.getTradeForeignPublicKeyHash(), hashOfSecretA);
-			String p2shAddressA = dogecoin.deriveP2shAddress(redeemScriptA);
-
-			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-			long p2shFee = Dogecoin.getInstance().getP2shFee(feeTimestamp);
-			final long minimumAmountA = tradeBotData.getForeignAmount() + p2shFee;
-
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(dogecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-
-			switch (htlcStatusA) {
-				case UNFUNDED:
-				case FUNDING_IN_PROGRESS:
-					// There might be another MESSAGE from someone else with an actually funded P2SH-A...
-					continue;
-
-				case REDEEM_IN_PROGRESS:
-				case REDEEMED:
-					// We've already redeemed this?
-					TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_DONE,
-							() -> String.format("P2SH-A %s already spent? Assuming trade complete", p2shAddressA));
-					return;
-
-				case REFUND_IN_PROGRESS:
-				case REFUNDED:
-					// This P2SH-A is burnt, but there might be another MESSAGE from someone else with an actually funded P2SH-A...
-					continue;
-
-				case FUNDED:
-					// Fall-through out of switch...
-					break;
-			}
-
-			// Good to go - send MESSAGE to AT
-
-			String aliceNativeAddress = Crypto.toAddress(messageTransactionData.getCreatorPublicKey());
-
-			// Build outgoing message, padding each part to 32 bytes to make it easier for AT to consume
-			byte[] outgoingMessageData = DogecoinACCTv2.buildTradeMessage(aliceNativeAddress, aliceForeignPublicKeyHash, hashOfSecretA, lockTimeA, refundTimeout);
-			String messageRecipient = tradeBotData.getAtAddress();
-
-			boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, outgoingMessageData);
-			if (!isMessageAlreadySent) {
-				PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
-				MessageTransaction outgoingMessageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, outgoingMessageData, false, false);
-
-				outgoingMessageTransaction.computeNonce();
-				outgoingMessageTransaction.sign(sender);
-
-				// reset repository state to prevent deadlock
-				repository.discardChanges();
-				ValidationResult result = outgoingMessageTransaction.importAsUnconfirmed();
-
-				if (result != ValidationResult.OK) {
-					LOGGER.warn(() -> String.format("Unable to send MESSAGE to AT %s: %s", messageRecipient, result.name()));
-					return;
-				}
-			}
-
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_WAITING_FOR_AT_REDEEM,
-					() -> String.format("Locked AT %s to %s. Waiting for AT redeem", tradeBotData.getAtAddress(), aliceNativeAddress));
-
-			return;
-		}
-	}
-
-	/**
-	 * Trade-bot is waiting for Bob's AT to switch to TRADE mode and lock trade to Alice only.
-	 * <p>
-	 * It's possible that Bob has cancelled his trade offer in the mean time, or that somehow
-	 * this process has taken so long that we've reached P2SH-A's locktime, or that someone else
-	 * has managed to trade with Bob. In any of these cases, trade-bot switches to begin the refunding process.
-	 * <p>
-	 * Assuming Bob's AT is locked to Alice, trade-bot checks AT's state data to make sure it is correct.
-	 * <p>
-	 * If all is well, trade-bot then redeems AT using Alice's secret-A, releasing Bob's QORT to Alice.
-	 * <p>
-	 * In revealing a valid secret-A, Bob can then redeem the DOGE funds from P2SH-A.
-	 * <p>
-	 * @throws ForeignBlockchainException
-	 */
-	private void handleAliceWaitingForAtLock(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		if (aliceUnexpectedState(repository, tradeBotData, atData, crossChainTradeData))
-			return;
-
-		Dogecoin dogecoin = Dogecoin.getInstance();
-		int lockTimeA = tradeBotData.getLockTimeA();
-
-		// Refund P2SH-A if we've passed lockTime-A
-		if (NTP.getTime() >= lockTimeA * 1000L) {
-			byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-			String p2shAddressA = dogecoin.deriveP2shAddress(redeemScriptA);
-
-			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-			long p2shFee = Dogecoin.getInstance().getP2shFee(feeTimestamp);
-			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(dogecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-
-			switch (htlcStatusA) {
-				case UNFUNDED:
-				case FUNDING_IN_PROGRESS:
-				case FUNDED:
-					break;
-
-				case REDEEM_IN_PROGRESS:
-				case REDEEMED:
-					// Already redeemed?
-					TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
-							() -> String.format("P2SH-A %s already spent? Assuming trade completed", p2shAddressA));
-					return;
-
-				case REFUND_IN_PROGRESS:
-				case REFUNDED:
-					TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDED,
-							() -> String.format("P2SH-A %s already refunded. Trade aborted", p2shAddressA));
-					return;
-
-			}
-
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
-					() -> atData.getIsFinished()
-					? String.format("AT %s cancelled. Refunding P2SH-A %s - aborting trade", tradeBotData.getAtAddress(), p2shAddressA)
-					: String.format("LockTime-A reached, refunding P2SH-A %s - aborting trade", p2shAddressA));
-
-			return;
-		}
-
-		// We're waiting for AT to be in TRADE mode
-		if (crossChainTradeData.mode != AcctMode.TRADING)
-			return;
-
-		// AT is in TRADE mode and locked to us as checked by aliceUnexpectedState() above
-
-		// Find our MESSAGE to AT from previous state
-		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(tradeBotData.getTradeNativePublicKey(),
-				crossChainTradeData.qortalCreatorTradeAddress, null, null, null);
-		if (messageTransactionsData == null || messageTransactionsData.isEmpty()) {
-			LOGGER.warn(() -> String.format("Unable to find our message to trade creator %s?", crossChainTradeData.qortalCreatorTradeAddress));
-			return;
-		}
-
-		long recipientMessageTimestamp = messageTransactionsData.get(0).getTimestamp();
-		int refundTimeout = DogecoinACCTv2.calcRefundTimeout(recipientMessageTimestamp, lockTimeA);
-
-		// Our calculated refundTimeout should match AT's refundTimeout
-		if (refundTimeout != crossChainTradeData.refundTimeout) {
-			LOGGER.debug(() -> String.format("Trade AT refundTimeout '%d' doesn't match our refundTimeout '%d'", crossChainTradeData.refundTimeout, refundTimeout));
-			// We'll eventually refund
-			return;
-		}
-
-		// We're good to redeem AT
-
-		// Send 'redeem' MESSAGE to AT using both secret
-		byte[] secretA = tradeBotData.getSecret();
-		String qortalReceivingAddress = Base58.encode(tradeBotData.getReceivingAccountInfo()); // Actually contains whole address, not just PKH
-		byte[] messageData = DogecoinACCTv2.buildRedeemMessage(secretA, qortalReceivingAddress);
-		String messageRecipient = tradeBotData.getAtAddress();
-
-		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
-		if (!isMessageAlreadySent) {
-			PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
-			MessageTransaction messageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, messageData, false, false);
-
-			messageTransaction.computeNonce();
-			messageTransaction.sign(sender);
-
-			// Reset repository state to prevent deadlock
-			repository.discardChanges();
-			ValidationResult result = messageTransaction.importAsUnconfirmed();
-
-			if (result != ValidationResult.OK) {
-				LOGGER.warn(() -> String.format("Unable to send MESSAGE to AT %s: %s", messageRecipient, result.name()));
-				return;
-			}
-		}
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
-				() -> String.format("Redeeming AT %s. Funds should arrive at %s",
-						tradeBotData.getAtAddress(), qortalReceivingAddress));
-	}
-
-	/**
-	 * Trade-bot is waiting for Alice to redeem Bob's AT, thus revealing secret-A which is required to spend the DOGE funds from P2SH-A.
-	 * <p>
-	 * It's possible that Bob's AT has reached its trading timeout and automatically refunded QORT back to Bob. In which case,
-	 * trade-bot is done with this specific trade and finalizes in refunded state.
-	 * <p>
-	 * Assuming trade-bot can extract a valid secret-A from Alice's MESSAGE then trade-bot uses that to redeem the DOGE funds from P2SH-A
-	 * to Bob's 'foreign'/Dogecoin trade legacy-format address, as derived from trade private key.
-	 * <p>
-	 * (This could potentially be 'improved' to send DOGE to any address of Bob's choosing by changing the transaction output).
-	 * <p>
-	 * If trade-bot successfully broadcasts the transaction, then this specific trade is done.
-	 * @throws ForeignBlockchainException
-	 */
-	private void handleBobWaitingForAtRedeem(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		// AT should be 'finished' once Alice has redeemed QORT funds
-		if (!atData.getIsFinished())
-			// Not finished yet
-			return;
-
-		// If AT is REFUNDED or CANCELLED then something has gone wrong
-		if (crossChainTradeData.mode == AcctMode.REFUNDED || crossChainTradeData.mode == AcctMode.CANCELLED) {
-			// Alice hasn't redeemed the QORT, so there is no point in trying to redeem the DOGE
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_REFUNDED,
-					() -> String.format("AT %s has auto-refunded - trade aborted", tradeBotData.getAtAddress()));
-
-			return;
-		}
-
-		byte[] secretA = DogecoinACCTv2.getInstance().findSecretA(repository, crossChainTradeData);
-		if (secretA == null) {
-			LOGGER.debug(() -> String.format("Unable to find secret-A from redeem message to AT %s?", tradeBotData.getAtAddress()));
-			return;
-		}
-
-		// Use secret-A to redeem P2SH-A
-
-		Dogecoin dogecoin = Dogecoin.getInstance();
-
-		byte[] receivingAccountInfo = tradeBotData.getReceivingAccountInfo();
-		int lockTimeA = crossChainTradeData.lockTimeA;
-		byte[] redeemScriptA = BitcoinyHTLC.buildScript(crossChainTradeData.partnerForeignPKH, lockTimeA, crossChainTradeData.creatorForeignPKH, crossChainTradeData.hashOfSecretA);
-		String p2shAddressA = dogecoin.deriveP2shAddress(redeemScriptA);
-
-		// Fee for redeem/refund is subtracted from P2SH-A balance.
-		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-		long p2shFee = Dogecoin.getInstance().getP2shFee(feeTimestamp);
-		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(dogecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-
-		switch (htlcStatusA) {
-			case UNFUNDED:
-			case FUNDING_IN_PROGRESS:
-				// P2SH-A suddenly not funded? Our best bet at this point is to hope for AT auto-refund
-				return;
-
-			case REDEEM_IN_PROGRESS:
-			case REDEEMED:
-				// Double-check that we have redeemed P2SH-A...
-				break;
-
-			case REFUND_IN_PROGRESS:
-			case REFUNDED:
-				// Wait for AT to auto-refund
-				return;
-
-			case FUNDED: {
-				Coin redeemAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
-				ECKey redeemKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-				List<TransactionOutput> fundingOutputs = dogecoin.getUnspentOutputs(p2shAddressA);
-
-				Transaction p2shRedeemTransaction = BitcoinyHTLC.buildRedeemTransaction(dogecoin.getNetworkParameters(), redeemAmount, redeemKey,
-						fundingOutputs, redeemScriptA, secretA, receivingAccountInfo);
-
-				dogecoin.broadcastTransaction(p2shRedeemTransaction);
-				break;
-			}
-		}
-
-		String receivingAddress = dogecoin.pkhToAddress(receivingAccountInfo);
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_DONE,
-				() -> String.format("P2SH-A %s redeemed. Funds should arrive at %s", tradeBotData.getAtAddress(), receivingAddress));
-	}
-
-	/**
-	 * Trade-bot is attempting to refund P2SH-A.
-	 * @throws ForeignBlockchainException
-	 */
-	private void handleAliceRefundingP2shA(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		int lockTimeA = tradeBotData.getLockTimeA();
-
-		// We can't refund P2SH-A until lockTime-A has passed
-		if (NTP.getTime() <= lockTimeA * 1000L)
-			return;
-
-		Dogecoin dogecoin = Dogecoin.getInstance();
-
-		// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
-		int medianBlockTime = dogecoin.getMedianBlockTime();
-		if (medianBlockTime <= lockTimeA)
-			return;
-
-		byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-		String p2shAddressA = dogecoin.deriveP2shAddress(redeemScriptA);
-
-		// Fee for redeem/refund is subtracted from P2SH-A balance.
-		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-		long p2shFee = Dogecoin.getInstance().getP2shFee(feeTimestamp);
-		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(dogecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-
-		switch (htlcStatusA) {
-			case UNFUNDED:
-			case FUNDING_IN_PROGRESS:
-				// Still waiting for P2SH-A to be funded...
-				return;
-
-			case REDEEM_IN_PROGRESS:
-			case REDEEMED:
-				// Too late!
-				TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
-						() -> String.format("P2SH-A %s already spent!", p2shAddressA));
-				return;
-
-			case REFUND_IN_PROGRESS:
-			case REFUNDED:
-				break;
-
-			case FUNDED:{
-				Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
-				ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-				List<TransactionOutput> fundingOutputs = dogecoin.getUnspentOutputs(p2shAddressA);
-
-				// Determine receive address for refund
-				String receiveAddress = dogecoin.getUnusedReceiveAddress(tradeBotData.getForeignKey());
-				Address receiving = Address.fromString(dogecoin.getNetworkParameters(), receiveAddress);
-
-				Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(dogecoin.getNetworkParameters(), refundAmount, refundKey,
-						fundingOutputs, redeemScriptA, lockTimeA, receiving.getHash());
-
-				dogecoin.broadcastTransaction(p2shRefundTransaction);
-				break;
-			}
-		}
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDED,
-				() -> String.format("LockTime-A reached. Refunded P2SH-A %s. Trade aborted", p2shAddressA));
-	}
-
-	/**
-	 * Returns true if Alice finds AT unexpectedly cancelled, refunded, redeemed or locked to someone else.
-	 * <p>
-	 * Will automatically update trade-bot state to <tt>ALICE_REFUNDING_A</tt> or <tt>ALICE_DONE</tt> as necessary.
-	 * 
-	 * @throws DataException
-	 * @throws ForeignBlockchainException
-	 */
-	private boolean aliceUnexpectedState(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		// This is OK
-		if (!atData.getIsFinished() && crossChainTradeData.mode == AcctMode.OFFERING)
-			return false;
-
-		boolean isAtLockedToUs = tradeBotData.getTradeNativeAddress().equals(crossChainTradeData.qortalPartnerAddress);
-
-		if (!atData.getIsFinished() && crossChainTradeData.mode == AcctMode.TRADING)
-			if (isAtLockedToUs) {
-				// AT is trading with us - OK
-				return false;
-			} else {
-				TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
-						() -> String.format("AT %s trading with someone else: %s. Refunding & aborting trade", tradeBotData.getAtAddress(), crossChainTradeData.qortalPartnerAddress));
-
-				return true;
-			}
-
-		if (atData.getIsFinished() && crossChainTradeData.mode == AcctMode.REDEEMED && isAtLockedToUs) {
-			// We've redeemed already?
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
-					() -> String.format("AT %s already redeemed by us. Trade completed", tradeBotData.getAtAddress()));
-		} else {
-			// Any other state is not good, so start defensive refund
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
-					() -> String.format("AT %s cancelled/refunded/redeemed by someone else/invalid state. Refunding & aborting trade", tradeBotData.getAtAddress()));
-		}
-
-		return true;
-	}
-
-	private long calcFeeTimestamp(int lockTimeA, int tradeTimeout) {
-		return (lockTimeA - tradeTimeout * 60) * 1000L;
-	}
-
-}

src/main/java/org/qortal/controller/tradebot/LitecoinACCTv2TradeBot.java

@@ -1,885 +0,0 @@
-package org.qortal.controller.tradebot;
-
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
-import org.bitcoinj.core.*;
-import org.bitcoinj.script.Script.ScriptType;
-import org.qortal.account.PrivateKeyAccount;
-import org.qortal.account.PublicKeyAccount;
-import org.qortal.api.model.crosschain.TradeBotCreateRequest;
-import org.qortal.asset.Asset;
-import org.qortal.crosschain.*;
-import org.qortal.crypto.Crypto;
-import org.qortal.data.at.ATData;
-import org.qortal.data.crosschain.CrossChainTradeData;
-import org.qortal.data.crosschain.TradeBotData;
-import org.qortal.data.transaction.BaseTransactionData;
-import org.qortal.data.transaction.DeployAtTransactionData;
-import org.qortal.data.transaction.MessageTransactionData;
-import org.qortal.group.Group;
-import org.qortal.repository.DataException;
-import org.qortal.repository.Repository;
-import org.qortal.transaction.DeployAtTransaction;
-import org.qortal.transaction.MessageTransaction;
-import org.qortal.transaction.Transaction.ValidationResult;
-import org.qortal.transform.TransformationException;
-import org.qortal.transform.transaction.DeployAtTransactionTransformer;
-import org.qortal.utils.Base58;
-import org.qortal.utils.NTP;
-
-import java.util.Arrays;
-import java.util.List;
-import java.util.Map;
-import java.util.stream.Collectors;
-
-import static java.util.Arrays.stream;
-import static java.util.stream.Collectors.toMap;
-
-/**
- * Performing cross-chain trading steps on behalf of user.
- * <p>
- * We deal with three different independent state-spaces here:
- * <ul>
- * 	<li>Qortal blockchain</li>
- * 	<li>Foreign blockchain</li>
- * 	<li>Trade-bot entries</li>
- * </ul>
- */
-public class LitecoinACCTv2TradeBot implements AcctTradeBot {
-
-	private static final Logger LOGGER = LogManager.getLogger(LitecoinACCTv2TradeBot.class);
-
-	public enum State implements TradeBot.StateNameAndValueSupplier {
-		BOB_WAITING_FOR_AT_CONFIRM(10, false, false),
-		BOB_WAITING_FOR_MESSAGE(15, true, true),
-		BOB_WAITING_FOR_AT_REDEEM(25, true, true),
-		BOB_DONE(30, false, false),
-		BOB_REFUNDED(35, false, false),
-
-		ALICE_WAITING_FOR_AT_LOCK(85, true, true),
-		ALICE_DONE(95, false, false),
-		ALICE_REFUNDING_A(105, true, true),
-		ALICE_REFUNDED(110, false, false);
-
-		private static final Map<Integer, State> map = stream(State.values()).collect(toMap(state -> state.value, state -> state));
-
-		public final int value;
-		public final boolean requiresAtData;
-		public final boolean requiresTradeData;
-
-		State(int value, boolean requiresAtData, boolean requiresTradeData) {
-			this.value = value;
-			this.requiresAtData = requiresAtData;
-			this.requiresTradeData = requiresTradeData;
-		}
-
-		public static State valueOf(int value) {
-			return map.get(value);
-		}
-
-		@Override
-		public String getState() {
-			return this.name();
-		}
-
-		@Override
-		public int getStateValue() {
-			return this.value;
-		}
-	}
-
-	/** Maximum time Bob waits for his AT creation transaction to be confirmed into a block. (milliseconds) */
-	private static final long MAX_AT_CONFIRMATION_PERIOD = 24 * 60 * 60 * 1000L; // ms
-
-	private static LitecoinACCTv2TradeBot instance;
-
-	private final List<String> endStates = Arrays.asList(State.BOB_DONE, State.BOB_REFUNDED, State.ALICE_DONE, State.ALICE_REFUNDING_A, State.ALICE_REFUNDED).stream()
-			.map(State::name)
-			.collect(Collectors.toUnmodifiableList());
-
-	private LitecoinACCTv2TradeBot() {
-	}
-
-	public static synchronized LitecoinACCTv2TradeBot getInstance() {
-		if (instance == null)
-			instance = new LitecoinACCTv2TradeBot();
-
-		return instance;
-	}
-
-	@Override
-	public List<String> getEndStates() {
-		return this.endStates;
-	}
-
-	/**
-	 * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for LTC.
-	 * <p>
-	 * Generates:
-	 * <ul>
-	 * 	<li>new 'trade' private key</li>
-	 * </ul>
-	 * Derives:
-	 * <ul>
-	 * 	<li>'native' (as in Qortal) public key, public key hash, address (starting with Q)</li>
-	 * 	<li>'foreign' (as in Litecoin) public key, public key hash</li>
-	 * </ul>
-	 * A Qortal AT is then constructed including the following as constants in the 'data segment':
-	 * <ul>
-	 * 	<li>'native'/Qortal 'trade' address - used as a MESSAGE contact</li>
-	 * 	<li>'foreign'/Litecoin public key hash - used by Alice's P2SH scripts to allow redeem</li>
-	 * 	<li>QORT amount on offer by Bob</li>
-	 * 	<li>LTC amount expected in return by Bob (from Alice)</li>
-	 * 	<li>trading timeout, in case things go wrong and everyone needs to refund</li>
-	 * </ul>
-	 * Returns a DEPLOY_AT transaction that needs to be signed and broadcast to the Qortal network.
-	 * <p>
-	 * Trade-bot will wait for Bob's AT to be deployed before taking next step.
-	 * <p>
-	 * @param repository
-	 * @param tradeBotCreateRequest
-	 * @return raw, unsigned DEPLOY_AT transaction
-	 * @throws DataException
-	 */
-	public byte[] createTrade(Repository repository, TradeBotCreateRequest tradeBotCreateRequest) throws DataException {
-		byte[] tradePrivateKey = TradeBot.generateTradePrivateKey();
-
-		byte[] tradeNativePublicKey = TradeBot.deriveTradeNativePublicKey(tradePrivateKey);
-		byte[] tradeNativePublicKeyHash = Crypto.hash160(tradeNativePublicKey);
-		String tradeNativeAddress = Crypto.toAddress(tradeNativePublicKey);
-
-		byte[] tradeForeignPublicKey = TradeBot.deriveTradeForeignPublicKey(tradePrivateKey);
-		byte[] tradeForeignPublicKeyHash = Crypto.hash160(tradeForeignPublicKey);
-
-		// Convert Litecoin receiving address into public key hash (we only support P2PKH at this time)
-		Address litecoinReceivingAddress;
-		try {
-			litecoinReceivingAddress = Address.fromString(Litecoin.getInstance().getNetworkParameters(), tradeBotCreateRequest.receivingAddress);
-		} catch (AddressFormatException e) {
-			throw new DataException("Unsupported Litecoin receiving address: " + tradeBotCreateRequest.receivingAddress);
-		}
-		if (litecoinReceivingAddress.getOutputScriptType() != ScriptType.P2PKH)
-			throw new DataException("Unsupported Litecoin receiving address: " + tradeBotCreateRequest.receivingAddress);
-
-		byte[] litecoinReceivingAccountInfo = litecoinReceivingAddress.getHash();
-
-		PublicKeyAccount creator = new PublicKeyAccount(repository, tradeBotCreateRequest.creatorPublicKey);
-
-		// Deploy AT
-		long timestamp = NTP.getTime();
-		byte[] reference = creator.getLastReference();
-		long fee = 0L;
-		byte[] signature = null;
-		BaseTransactionData baseTransactionData = new BaseTransactionData(timestamp, Group.NO_GROUP, reference, creator.getPublicKey(), fee, signature);
-
-		String name = "QORT/LTC ACCT";
-		String description = "QORT/LTC cross-chain trade";
-		String aTType = "ACCT";
-		String tags = "ACCT QORT LTC";
-		byte[] creationBytes = LitecoinACCTv2.buildQortalAT(tradeNativeAddress, tradeForeignPublicKeyHash, tradeBotCreateRequest.qortAmount,
-				tradeBotCreateRequest.foreignAmount, tradeBotCreateRequest.tradeTimeout);
-		long amount = tradeBotCreateRequest.fundingQortAmount;
-
-		DeployAtTransactionData deployAtTransactionData = new DeployAtTransactionData(baseTransactionData, name, description, aTType, tags, creationBytes, amount, Asset.QORT);
-
-		DeployAtTransaction deployAtTransaction = new DeployAtTransaction(repository, deployAtTransactionData);
-		fee = deployAtTransaction.calcRecommendedFee();
-		deployAtTransactionData.setFee(fee);
-
-		DeployAtTransaction.ensureATAddress(deployAtTransactionData);
-		String atAddress = deployAtTransactionData.getAtAddress();
-
-		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, LitecoinACCTv2.NAME,
-				State.BOB_WAITING_FOR_AT_CONFIRM.name(), State.BOB_WAITING_FOR_AT_CONFIRM.value,
-				creator.getAddress(), atAddress, timestamp, tradeBotCreateRequest.qortAmount,
-				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
-				null, null,
-				SupportedBlockchain.LITECOIN.name(),
-				tradeForeignPublicKey, tradeForeignPublicKeyHash,
-				tradeBotCreateRequest.foreignAmount, null, null, null, litecoinReceivingAccountInfo);
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Built AT %s. Waiting for deployment", atAddress));
-
-		// Attempt to backup the trade bot data
-		TradeBot.backupTradeBotData(repository, null);
-
-		// Return to user for signing and broadcast as we don't have their Qortal private key
-		try {
-			return DeployAtTransactionTransformer.toBytes(deployAtTransactionData);
-		} catch (TransformationException e) {
-			throw new DataException("Failed to transform DEPLOY_AT transaction?", e);
-		}
-	}
-
-	/**
-	 * Creates a trade-bot entry from the 'Alice' viewpoint, i.e. matching LTC to an existing offer.
-	 * <p>
-	 * Requires a chosen trade offer from Bob, passed by <tt>crossChainTradeData</tt>
-	 * and access to a Litecoin wallet via <tt>xprv58</tt>.
-	 * <p>
-	 * The <tt>crossChainTradeData</tt> contains the current trade offer state
-	 * as extracted from the AT's data segment.
-	 * <p>
-	 * Access to a funded wallet is via a Litecoin BIP32 hierarchical deterministic key,
-	 * passed via <tt>xprv58</tt>.
-	 * <b>This key will be stored in your node's database</b>
-	 * to allow trade-bot to create/fund the necessary P2SH transactions!
-	 * However, due to the nature of BIP32 keys, it is possible to give the trade-bot
-	 * only a subset of wallet access (see BIP32 for more details).
-	 * <p>
-	 * As an example, the xprv58 can be extract from a <i>legacy, password-less</i>
-	 * Electrum wallet by going to the console tab and entering:<br>
-	 * <tt>wallet.keystore.xprv</tt><br>
-	 * which should result in a base58 string starting with either 'xprv' (for Litecoin main-net)
-	 * or 'tprv' for (Litecoin test-net).
-	 * <p>
-	 * It is envisaged that the value in <tt>xprv58</tt> will actually come from a Qortal-UI-managed wallet.
-	 * <p>
-	 * If sufficient funds are available, <b>this method will actually fund the P2SH-A</b>
-	 * with the Litecoin amount expected by 'Bob'.
-	 * <p>
-	 * If the Litecoin transaction is successfully broadcast to the network then
-	 * we also send a MESSAGE to Bob's trade-bot to let them know.
-	 * <p>
-	 * The trade-bot entry is saved to the repository and the cross-chain trading process commences.
-	 * <p>
-	 * @param repository
-	 * @param crossChainTradeData chosen trade OFFER that Alice wants to match
-	 * @param xprv58 funded wallet xprv in base58
-	 * @return true if P2SH-A funding transaction successfully broadcast to Litecoin network, false otherwise
-	 * @throws DataException
-	 */
-	public ResponseResult startResponse(Repository repository, ATData atData, ACCT acct, CrossChainTradeData crossChainTradeData, String xprv58, String receivingAddress) throws DataException {
-		byte[] tradePrivateKey = TradeBot.generateTradePrivateKey();
-		byte[] secretA = TradeBot.generateSecret();
-		byte[] hashOfSecretA = Crypto.hash160(secretA);
-
-		byte[] tradeNativePublicKey = TradeBot.deriveTradeNativePublicKey(tradePrivateKey);
-		byte[] tradeNativePublicKeyHash = Crypto.hash160(tradeNativePublicKey);
-		String tradeNativeAddress = Crypto.toAddress(tradeNativePublicKey);
-
-		byte[] tradeForeignPublicKey = TradeBot.deriveTradeForeignPublicKey(tradePrivateKey);
-		byte[] tradeForeignPublicKeyHash = Crypto.hash160(tradeForeignPublicKey);
-		byte[] receivingPublicKeyHash = Base58.decode(receivingAddress); // Actually the whole address, not just PKH
-
-		// We need to generate lockTime-A: add tradeTimeout to now
-		long now = NTP.getTime();
-		int lockTimeA = crossChainTradeData.tradeTimeout * 60 + (int) (now / 1000L);
-
-		TradeBotData tradeBotData =  new TradeBotData(tradePrivateKey, LitecoinACCTv2.NAME,
-				State.ALICE_WAITING_FOR_AT_LOCK.name(), State.ALICE_WAITING_FOR_AT_LOCK.value,
-				receivingAddress, crossChainTradeData.qortalAtAddress, now, crossChainTradeData.qortAmount,
-				tradeNativePublicKey, tradeNativePublicKeyHash, tradeNativeAddress,
-				secretA, hashOfSecretA,
-				SupportedBlockchain.LITECOIN.name(),
-				tradeForeignPublicKey, tradeForeignPublicKeyHash,
-				crossChainTradeData.expectedForeignAmount, xprv58, null, lockTimeA, receivingPublicKeyHash);
-
-		// Attempt to backup the trade bot data
-		// Include tradeBotData as an additional parameter, since it's not in the repository yet
-		TradeBot.backupTradeBotData(repository, Arrays.asList(tradeBotData));
-
-		// Check we have enough funds via xprv58 to fund P2SH to cover expectedForeignAmount
-		long p2shFee;
-		try {
-			p2shFee = Litecoin.getInstance().getP2shFee(now);
-		} catch (ForeignBlockchainException e) {
-			LOGGER.debug("Couldn't estimate Litecoin fees?");
-			return ResponseResult.NETWORK_ISSUE;
-		}
-
-		// Fee for redeem/refund is subtracted from P2SH-A balance.
-		// Do not include fee for funding transaction as this is covered by buildSpend()
-		long amountA = crossChainTradeData.expectedForeignAmount + p2shFee /*redeeming/refunding P2SH-A*/;
-
-		// P2SH-A to be funded
-		byte[] redeemScriptBytes = BitcoinyHTLC.buildScript(tradeForeignPublicKeyHash, lockTimeA, crossChainTradeData.creatorForeignPKH, hashOfSecretA);
-		String p2shAddress = Litecoin.getInstance().deriveP2shAddress(redeemScriptBytes);
-
-		// Build transaction for funding P2SH-A
-		Transaction p2shFundingTransaction = Litecoin.getInstance().buildSpend(tradeBotData.getForeignKey(), p2shAddress, amountA);
-		if (p2shFundingTransaction == null) {
-			LOGGER.debug("Unable to build P2SH-A funding transaction - lack of funds?");
-			return ResponseResult.BALANCE_ISSUE;
-		}
-
-		try {
-			Litecoin.getInstance().broadcastTransaction(p2shFundingTransaction);
-		} catch (ForeignBlockchainException e) {
-			// We couldn't fund P2SH-A at this time
-			LOGGER.debug("Couldn't broadcast P2SH-A funding transaction?");
-			return ResponseResult.NETWORK_ISSUE;
-		}
-
-		// Attempt to send MESSAGE to Bob's Qortal trade address
-		byte[] messageData = LitecoinACCTv2.buildOfferMessage(tradeBotData.getTradeForeignPublicKeyHash(), tradeBotData.getHashOfSecret(), tradeBotData.getLockTimeA());
-		String messageRecipient = crossChainTradeData.qortalCreatorTradeAddress;
-
-		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
-		if (!isMessageAlreadySent) {
-			PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
-			MessageTransaction messageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, messageData, false, false);
-
-			messageTransaction.computeNonce();
-			messageTransaction.sign(sender);
-
-			// reset repository state to prevent deadlock
-			repository.discardChanges();
-			ValidationResult result = messageTransaction.importAsUnconfirmed();
-
-			if (result != ValidationResult.OK) {
-				LOGGER.warn(() -> String.format("Unable to send MESSAGE to Bob's trade-bot %s: %s", messageRecipient, result.name()));
-				return ResponseResult.NETWORK_ISSUE;
-			}
-		}
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Funding P2SH-A %s. Messaged Bob. Waiting for AT-lock", p2shAddress));
-
-		return ResponseResult.OK;
-	}
-
-	@Override
-	public boolean canDelete(Repository repository, TradeBotData tradeBotData) throws DataException {
-		State tradeBotState = State.valueOf(tradeBotData.getStateValue());
-		if (tradeBotState == null)
-			return true;
-
-		// If the AT doesn't exist then we might as well let the user tidy up
-		if (!repository.getATRepository().exists(tradeBotData.getAtAddress()))
-			return true;
-
-		switch (tradeBotState) {
-			case BOB_WAITING_FOR_AT_CONFIRM:
-			case ALICE_DONE:
-			case BOB_DONE:
-			case ALICE_REFUNDED:
-			case BOB_REFUNDED:
-			case ALICE_REFUNDING_A:
-				return true;
-
-			default:
-				return false;
-		}
-	}
-
-	@Override
-	public void progress(Repository repository, TradeBotData tradeBotData) throws DataException, ForeignBlockchainException {
-		State tradeBotState = State.valueOf(tradeBotData.getStateValue());
-		if (tradeBotState == null) {
-			LOGGER.info(() -> String.format("Trade-bot entry for AT %s has invalid state?", tradeBotData.getAtAddress()));
-			return;
-		}
-
-		ATData atData = null;
-		CrossChainTradeData tradeData = null;
-
-		if (tradeBotState.requiresAtData) {
-			// Attempt to fetch AT data
-			atData = repository.getATRepository().fromATAddress(tradeBotData.getAtAddress());
-			if (atData == null) {
-				LOGGER.debug(() -> String.format("Unable to fetch trade AT %s from repository", tradeBotData.getAtAddress()));
-				return;
-			}
-
-			if (tradeBotState.requiresTradeData) {
-				tradeData = LitecoinACCTv2.getInstance().populateTradeData(repository, atData);
-				if (tradeData == null) {
-					LOGGER.warn(() -> String.format("Unable to fetch ACCT trade data for AT %s from repository", tradeBotData.getAtAddress()));
-					return;
-				}
-			}
-		}
-
-		switch (tradeBotState) {
-			case BOB_WAITING_FOR_AT_CONFIRM:
-				handleBobWaitingForAtConfirm(repository, tradeBotData);
-				break;
-
-			case BOB_WAITING_FOR_MESSAGE:
-				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
-				handleBobWaitingForMessage(repository, tradeBotData, atData, tradeData);
-				break;
-
-			case ALICE_WAITING_FOR_AT_LOCK:
-				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
-				handleAliceWaitingForAtLock(repository, tradeBotData, atData, tradeData);
-				break;
-
-			case BOB_WAITING_FOR_AT_REDEEM:
-				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
-				handleBobWaitingForAtRedeem(repository, tradeBotData, atData, tradeData);
-				break;
-
-			case ALICE_DONE:
-			case BOB_DONE:
-				break;
-
-			case ALICE_REFUNDING_A:
-				TradeBot.getInstance().updatePresence(repository, tradeBotData, tradeData);
-				handleAliceRefundingP2shA(repository, tradeBotData, atData, tradeData);
-				break;
-
-			case ALICE_REFUNDED:
-			case BOB_REFUNDED:
-				break;
-		}
-	}
-
-	/**
-	 * Trade-bot is waiting for Bob's AT to deploy.
-	 * <p>
-	 * If AT is deployed, then trade-bot's next step is to wait for MESSAGE from Alice.
-	 */
-	private void handleBobWaitingForAtConfirm(Repository repository, TradeBotData tradeBotData) throws DataException {
-		if (!repository.getATRepository().exists(tradeBotData.getAtAddress())) {
-			if (NTP.getTime() - tradeBotData.getTimestamp() <= MAX_AT_CONFIRMATION_PERIOD)
-				return;
-
-			// We've waited ages for AT to be confirmed into a block but something has gone awry.
-			// After this long we assume transaction loss so give up with trade-bot entry too.
-			tradeBotData.setState(State.BOB_REFUNDED.name());
-			tradeBotData.setStateValue(State.BOB_REFUNDED.value);
-			tradeBotData.setTimestamp(NTP.getTime());
-			// We delete trade-bot entry here instead of saving, hence not using updateTradeBotState()
-			repository.getCrossChainRepository().delete(tradeBotData.getTradePrivateKey());
-			repository.saveChanges();
-
-			LOGGER.info(() -> String.format("AT %s never confirmed. Giving up on trade", tradeBotData.getAtAddress()));
-			TradeBot.notifyStateChange(tradeBotData);
-			return;
-		}
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_WAITING_FOR_MESSAGE,
-				() -> String.format("AT %s confirmed ready. Waiting for trade message", tradeBotData.getAtAddress()));
-	}
-
-	/**
-	 * Trade-bot is waiting for MESSAGE from Alice's trade-bot, containing Alice's trade info.
-	 * <p>
-	 * It's possible Bob has cancelling his trade offer, receiving an automatic QORT refund,
-	 * in which case trade-bot is done with this specific trade and finalizes on refunded state.
-	 * <p>
-	 * Assuming trade is still on offer, trade-bot checks the contents of MESSAGE from Alice's trade-bot.
-	 * <p>
-	 * Details from Alice are used to derive P2SH-A address and this is checked for funding balance.
-	 * <p>
-	 * Assuming P2SH-A has at least expected Litecoin balance,
-	 * Bob's trade-bot constructs a zero-fee, PoW MESSAGE to send to Bob's AT with more trade details.
-	 * <p>
-	 * On processing this MESSAGE, Bob's AT should switch into 'TRADE' mode and only trade with Alice.
-	 * <p>
-	 * Trade-bot's next step is to wait for Alice to redeem the AT, which will allow Bob to
-	 * extract secret-A needed to redeem Alice's P2SH.
-	 * @throws ForeignBlockchainException
-	 */
-	private void handleBobWaitingForMessage(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		// If AT has finished then Bob likely cancelled his trade offer
-		if (atData.getIsFinished()) {
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_REFUNDED,
-					() -> String.format("AT %s cancelled - trading aborted", tradeBotData.getAtAddress()));
-			return;
-		}
-
-		Litecoin litecoin = Litecoin.getInstance();
-
-		String address = tradeBotData.getTradeNativeAddress();
-		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(null, address, null, null, null);
-
-		for (MessageTransactionData messageTransactionData : messageTransactionsData) {
-			if (messageTransactionData.isText())
-				continue;
-
-			// We're expecting: HASH160(secret-A), Alice's Litecoin pubkeyhash and lockTime-A
-			byte[] messageData = messageTransactionData.getData();
-			LitecoinACCTv2.OfferMessageData offerMessageData = LitecoinACCTv2.extractOfferMessageData(messageData);
-			if (offerMessageData == null)
-				continue;
-
-			byte[] aliceForeignPublicKeyHash = offerMessageData.partnerLitecoinPKH;
-			byte[] hashOfSecretA = offerMessageData.hashOfSecretA;
-			int lockTimeA = (int) offerMessageData.lockTimeA;
-			long messageTimestamp = messageTransactionData.getTimestamp();
-			int refundTimeout = LitecoinACCTv2.calcRefundTimeout(messageTimestamp, lockTimeA);
-
-			// Determine P2SH-A address and confirm funded
-			byte[] redeemScriptA = BitcoinyHTLC.buildScript(aliceForeignPublicKeyHash, lockTimeA, tradeBotData.getTradeForeignPublicKeyHash(), hashOfSecretA);
-			String p2shAddressA = litecoin.deriveP2shAddress(redeemScriptA);
-
-			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-			long p2shFee = Litecoin.getInstance().getP2shFee(feeTimestamp);
-			final long minimumAmountA = tradeBotData.getForeignAmount() + p2shFee;
-
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(litecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-
-			switch (htlcStatusA) {
-				case UNFUNDED:
-				case FUNDING_IN_PROGRESS:
-					// There might be another MESSAGE from someone else with an actually funded P2SH-A...
-					continue;
-
-				case REDEEM_IN_PROGRESS:
-				case REDEEMED:
-					// We've already redeemed this?
-					TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_DONE,
-							() -> String.format("P2SH-A %s already spent? Assuming trade complete", p2shAddressA));
-					return;
-
-				case REFUND_IN_PROGRESS:
-				case REFUNDED:
-					// This P2SH-A is burnt, but there might be another MESSAGE from someone else with an actually funded P2SH-A...
-					continue;
-
-				case FUNDED:
-					// Fall-through out of switch...
-					break;
-			}
-
-			// Good to go - send MESSAGE to AT
-
-			String aliceNativeAddress = Crypto.toAddress(messageTransactionData.getCreatorPublicKey());
-
-			// Build outgoing message, padding each part to 32 bytes to make it easier for AT to consume
-			byte[] outgoingMessageData = LitecoinACCTv2.buildTradeMessage(aliceNativeAddress, aliceForeignPublicKeyHash, hashOfSecretA, lockTimeA, refundTimeout);
-			String messageRecipient = tradeBotData.getAtAddress();
-
-			boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, outgoingMessageData);
-			if (!isMessageAlreadySent) {
-				PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
-				MessageTransaction outgoingMessageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, outgoingMessageData, false, false);
-
-				outgoingMessageTransaction.computeNonce();
-				outgoingMessageTransaction.sign(sender);
-
-				// reset repository state to prevent deadlock
-				repository.discardChanges();
-				ValidationResult result = outgoingMessageTransaction.importAsUnconfirmed();
-
-				if (result != ValidationResult.OK) {
-					LOGGER.warn(() -> String.format("Unable to send MESSAGE to AT %s: %s", messageRecipient, result.name()));
-					return;
-				}
-			}
-
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_WAITING_FOR_AT_REDEEM,
-					() -> String.format("Locked AT %s to %s. Waiting for AT redeem", tradeBotData.getAtAddress(), aliceNativeAddress));
-
-			return;
-		}
-	}
-
-	/**
-	 * Trade-bot is waiting for Bob's AT to switch to TRADE mode and lock trade to Alice only.
-	 * <p>
-	 * It's possible that Bob has cancelled his trade offer in the mean time, or that somehow
-	 * this process has taken so long that we've reached P2SH-A's locktime, or that someone else
-	 * has managed to trade with Bob. In any of these cases, trade-bot switches to begin the refunding process.
-	 * <p>
-	 * Assuming Bob's AT is locked to Alice, trade-bot checks AT's state data to make sure it is correct.
-	 * <p>
-	 * If all is well, trade-bot then redeems AT using Alice's secret-A, releasing Bob's QORT to Alice.
-	 * <p>
-	 * In revealing a valid secret-A, Bob can then redeem the LTC funds from P2SH-A.
-	 * <p>
-	 * @throws ForeignBlockchainException
-	 */
-	private void handleAliceWaitingForAtLock(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		if (aliceUnexpectedState(repository, tradeBotData, atData, crossChainTradeData))
-			return;
-
-		Litecoin litecoin = Litecoin.getInstance();
-		int lockTimeA = tradeBotData.getLockTimeA();
-
-		// Refund P2SH-A if we've passed lockTime-A
-		if (NTP.getTime() >= lockTimeA * 1000L) {
-			byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-			String p2shAddressA = litecoin.deriveP2shAddress(redeemScriptA);
-
-			long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-			long p2shFee = Litecoin.getInstance().getP2shFee(feeTimestamp);
-			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-
-			BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(litecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-
-			switch (htlcStatusA) {
-				case UNFUNDED:
-				case FUNDING_IN_PROGRESS:
-				case FUNDED:
-					break;
-
-				case REDEEM_IN_PROGRESS:
-				case REDEEMED:
-					// Already redeemed?
-					TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
-							() -> String.format("P2SH-A %s already spent? Assuming trade completed", p2shAddressA));
-					return;
-
-				case REFUND_IN_PROGRESS:
-				case REFUNDED:
-					TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDED,
-							() -> String.format("P2SH-A %s already refunded. Trade aborted", p2shAddressA));
-					return;
-
-			}
-
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
-					() -> atData.getIsFinished()
-					? String.format("AT %s cancelled. Refunding P2SH-A %s - aborting trade", tradeBotData.getAtAddress(), p2shAddressA)
-					: String.format("LockTime-A reached, refunding P2SH-A %s - aborting trade", p2shAddressA));
-
-			return;
-		}
-
-		// We're waiting for AT to be in TRADE mode
-		if (crossChainTradeData.mode != AcctMode.TRADING)
-			return;
-
-		// AT is in TRADE mode and locked to us as checked by aliceUnexpectedState() above
-
-		// Find our MESSAGE to AT from previous state
-		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(tradeBotData.getTradeNativePublicKey(),
-				crossChainTradeData.qortalCreatorTradeAddress, null, null, null);
-		if (messageTransactionsData == null || messageTransactionsData.isEmpty()) {
-			LOGGER.warn(() -> String.format("Unable to find our message to trade creator %s?", crossChainTradeData.qortalCreatorTradeAddress));
-			return;
-		}
-
-		long recipientMessageTimestamp = messageTransactionsData.get(0).getTimestamp();
-		int refundTimeout = LitecoinACCTv2.calcRefundTimeout(recipientMessageTimestamp, lockTimeA);
-
-		// Our calculated refundTimeout should match AT's refundTimeout
-		if (refundTimeout != crossChainTradeData.refundTimeout) {
-			LOGGER.debug(() -> String.format("Trade AT refundTimeout '%d' doesn't match our refundTimeout '%d'", crossChainTradeData.refundTimeout, refundTimeout));
-			// We'll eventually refund
-			return;
-		}
-
-		// We're good to redeem AT
-
-		// Send 'redeem' MESSAGE to AT using both secret
-		byte[] secretA = tradeBotData.getSecret();
-		String qortalReceivingAddress = Base58.encode(tradeBotData.getReceivingAccountInfo()); // Actually contains whole address, not just PKH
-		byte[] messageData = LitecoinACCTv2.buildRedeemMessage(secretA, qortalReceivingAddress);
-		String messageRecipient = tradeBotData.getAtAddress();
-
-		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
-		if (!isMessageAlreadySent) {
-			PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
-			MessageTransaction messageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, messageData, false, false);
-
-			messageTransaction.computeNonce();
-			messageTransaction.sign(sender);
-
-			// Reset repository state to prevent deadlock
-			repository.discardChanges();
-			ValidationResult result = messageTransaction.importAsUnconfirmed();
-
-			if (result != ValidationResult.OK) {
-				LOGGER.warn(() -> String.format("Unable to send MESSAGE to AT %s: %s", messageRecipient, result.name()));
-				return;
-			}
-		}
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
-				() -> String.format("Redeeming AT %s. Funds should arrive at %s",
-						tradeBotData.getAtAddress(), qortalReceivingAddress));
-	}
-
-	/**
-	 * Trade-bot is waiting for Alice to redeem Bob's AT, thus revealing secret-A which is required to spend the LTC funds from P2SH-A.
-	 * <p>
-	 * It's possible that Bob's AT has reached its trading timeout and automatically refunded QORT back to Bob. In which case,
-	 * trade-bot is done with this specific trade and finalizes in refunded state.
-	 * <p>
-	 * Assuming trade-bot can extract a valid secret-A from Alice's MESSAGE then trade-bot uses that to redeem the LTC funds from P2SH-A
-	 * to Bob's 'foreign'/Litecoin trade legacy-format address, as derived from trade private key.
-	 * <p>
-	 * (This could potentially be 'improved' to send LTC to any address of Bob's choosing by changing the transaction output).
-	 * <p>
-	 * If trade-bot successfully broadcasts the transaction, then this specific trade is done.
-	 * @throws ForeignBlockchainException
-	 */
-	private void handleBobWaitingForAtRedeem(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		// AT should be 'finished' once Alice has redeemed QORT funds
-		if (!atData.getIsFinished())
-			// Not finished yet
-			return;
-
-		// If AT is REFUNDED or CANCELLED then something has gone wrong
-		if (crossChainTradeData.mode == AcctMode.REFUNDED || crossChainTradeData.mode == AcctMode.CANCELLED) {
-			// Alice hasn't redeemed the QORT, so there is no point in trying to redeem the LTC
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_REFUNDED,
-					() -> String.format("AT %s has auto-refunded - trade aborted", tradeBotData.getAtAddress()));
-
-			return;
-		}
-
-		byte[] secretA = LitecoinACCTv2.getInstance().findSecretA(repository, crossChainTradeData);
-		if (secretA == null) {
-			LOGGER.debug(() -> String.format("Unable to find secret-A from redeem message to AT %s?", tradeBotData.getAtAddress()));
-			return;
-		}
-
-		// Use secret-A to redeem P2SH-A
-
-		Litecoin litecoin = Litecoin.getInstance();
-
-		byte[] receivingAccountInfo = tradeBotData.getReceivingAccountInfo();
-		int lockTimeA = crossChainTradeData.lockTimeA;
-		byte[] redeemScriptA = BitcoinyHTLC.buildScript(crossChainTradeData.partnerForeignPKH, lockTimeA, crossChainTradeData.creatorForeignPKH, crossChainTradeData.hashOfSecretA);
-		String p2shAddressA = litecoin.deriveP2shAddress(redeemScriptA);
-
-		// Fee for redeem/refund is subtracted from P2SH-A balance.
-		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-		long p2shFee = Litecoin.getInstance().getP2shFee(feeTimestamp);
-		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(litecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-
-		switch (htlcStatusA) {
-			case UNFUNDED:
-			case FUNDING_IN_PROGRESS:
-				// P2SH-A suddenly not funded? Our best bet at this point is to hope for AT auto-refund
-				return;
-
-			case REDEEM_IN_PROGRESS:
-			case REDEEMED:
-				// Double-check that we have redeemed P2SH-A...
-				break;
-
-			case REFUND_IN_PROGRESS:
-			case REFUNDED:
-				// Wait for AT to auto-refund
-				return;
-
-			case FUNDED: {
-				Coin redeemAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
-				ECKey redeemKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-				List<TransactionOutput> fundingOutputs = litecoin.getUnspentOutputs(p2shAddressA);
-
-				Transaction p2shRedeemTransaction = BitcoinyHTLC.buildRedeemTransaction(litecoin.getNetworkParameters(), redeemAmount, redeemKey,
-						fundingOutputs, redeemScriptA, secretA, receivingAccountInfo);
-
-				litecoin.broadcastTransaction(p2shRedeemTransaction);
-				break;
-			}
-		}
-
-		String receivingAddress = litecoin.pkhToAddress(receivingAccountInfo);
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, State.BOB_DONE,
-				() -> String.format("P2SH-A %s redeemed. Funds should arrive at %s", tradeBotData.getAtAddress(), receivingAddress));
-	}
-
-	/**
-	 * Trade-bot is attempting to refund P2SH-A.
-	 * @throws ForeignBlockchainException
-	 */
-	private void handleAliceRefundingP2shA(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		int lockTimeA = tradeBotData.getLockTimeA();
-
-		// We can't refund P2SH-A until lockTime-A has passed
-		if (NTP.getTime() <= lockTimeA * 1000L)
-			return;
-
-		Litecoin litecoin = Litecoin.getInstance();
-
-		// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
-		int medianBlockTime = litecoin.getMedianBlockTime();
-		if (medianBlockTime <= lockTimeA)
-			return;
-
-		byte[] redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTimeA, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-		String p2shAddressA = litecoin.deriveP2shAddress(redeemScriptA);
-
-		// Fee for redeem/refund is subtracted from P2SH-A balance.
-		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
-		long p2shFee = Litecoin.getInstance().getP2shFee(feeTimestamp);
-		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		BitcoinyHTLC.Status htlcStatusA = BitcoinyHTLC.determineHtlcStatus(litecoin.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-
-		switch (htlcStatusA) {
-			case UNFUNDED:
-			case FUNDING_IN_PROGRESS:
-				// Still waiting for P2SH-A to be funded...
-				return;
-
-			case REDEEM_IN_PROGRESS:
-			case REDEEMED:
-				// Too late!
-				TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
-						() -> String.format("P2SH-A %s already spent!", p2shAddressA));
-				return;
-
-			case REFUND_IN_PROGRESS:
-			case REFUNDED:
-				break;
-
-			case FUNDED:{
-				Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
-				ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-				List<TransactionOutput> fundingOutputs = litecoin.getUnspentOutputs(p2shAddressA);
-
-				// Determine receive address for refund
-				String receiveAddress = litecoin.getUnusedReceiveAddress(tradeBotData.getForeignKey());
-				Address receiving = Address.fromString(litecoin.getNetworkParameters(), receiveAddress);
-
-				Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(litecoin.getNetworkParameters(), refundAmount, refundKey,
-						fundingOutputs, redeemScriptA, lockTimeA, receiving.getHash());
-
-				litecoin.broadcastTransaction(p2shRefundTransaction);
-				break;
-			}
-		}
-
-		TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDED,
-				() -> String.format("LockTime-A reached. Refunded P2SH-A %s. Trade aborted", p2shAddressA));
-	}
-
-	/**
-	 * Returns true if Alice finds AT unexpectedly cancelled, refunded, redeemed or locked to someone else.
-	 * <p>
-	 * Will automatically update trade-bot state to <tt>ALICE_REFUNDING_A</tt> or <tt>ALICE_DONE</tt> as necessary.
-	 * 
-	 * @throws DataException
-	 * @throws ForeignBlockchainException
-	 */
-	private boolean aliceUnexpectedState(Repository repository, TradeBotData tradeBotData,
-			ATData atData, CrossChainTradeData crossChainTradeData) throws DataException, ForeignBlockchainException {
-		// This is OK
-		if (!atData.getIsFinished() && crossChainTradeData.mode == AcctMode.OFFERING)
-			return false;
-
-		boolean isAtLockedToUs = tradeBotData.getTradeNativeAddress().equals(crossChainTradeData.qortalPartnerAddress);
-
-		if (!atData.getIsFinished() && crossChainTradeData.mode == AcctMode.TRADING)
-			if (isAtLockedToUs) {
-				// AT is trading with us - OK
-				return false;
-			} else {
-				TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
-						() -> String.format("AT %s trading with someone else: %s. Refunding & aborting trade", tradeBotData.getAtAddress(), crossChainTradeData.qortalPartnerAddress));
-
-				return true;
-			}
-
-		if (atData.getIsFinished() && crossChainTradeData.mode == AcctMode.REDEEMED && isAtLockedToUs) {
-			// We've redeemed already?
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_DONE,
-					() -> String.format("AT %s already redeemed by us. Trade completed", tradeBotData.getAtAddress()));
-		} else {
-			// Any other state is not good, so start defensive refund
-			TradeBot.updateTradeBotState(repository, tradeBotData, State.ALICE_REFUNDING_A,
-					() -> String.format("AT %s cancelled/refunded/redeemed by someone else/invalid state. Refunding & aborting trade", tradeBotData.getAtAddress()));
-		}
-
-		return true;
-	}
-
-	private long calcFeeTimestamp(int lockTimeA, int tradeTimeout) {
-		return (lockTimeA - tradeTimeout * 60) * 1000L;
-	}
-
-}

src/main/java/org/qortal/controller/tradebot/LitecoinACCTv3TradeBot.java

@@ -19,6 +19,7 @@ import org.qortal.data.transaction.MessageTransactionData;
 import org.qortal.group.Group;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
+import org.qortal.repository.RepositoryManager;
 import org.qortal.transaction.DeployAtTransaction;
 import org.qortal.transaction.MessageTransaction;
 import org.qortal.transaction.Transaction.ValidationResult;
@@ -317,20 +318,27 @@ public class LitecoinACCTv3TradeBot implements AcctTradeBot {
 
 		boolean isMessageAlreadySent = repository.getMessageRepository().exists(tradeBotData.getTradeNativePublicKey(), messageRecipient, messageData);
 		if (!isMessageAlreadySent) {
-			PrivateKeyAccount sender = new PrivateKeyAccount(repository, tradeBotData.getTradePrivateKey());
-			MessageTransaction messageTransaction = MessageTransaction.build(repository, sender, Group.NO_GROUP, messageRecipient, messageData, false, false);
+			// Do this in a new thread so caller doesn't have to wait for computeNonce()
+			// In the unlikely event that the transaction doesn't validate then the buy won't happen and eventually Alice's AT will be refunded
+			new Thread(() -> {
+				try (final Repository threadsRepository = RepositoryManager.getRepository()) {
+					PrivateKeyAccount sender = new PrivateKeyAccount(threadsRepository, tradeBotData.getTradePrivateKey());
+					MessageTransaction messageTransaction = MessageTransaction.build(threadsRepository, sender, Group.NO_GROUP, messageRecipient, messageData, false, false);
 
-			messageTransaction.computeNonce();
-			messageTransaction.sign(sender);
+					messageTransaction.computeNonce();
+					messageTransaction.sign(sender);
 
-			// reset repository state to prevent deadlock
-			repository.discardChanges();
-			ValidationResult result = messageTransaction.importAsUnconfirmed();
+					// reset repository state to prevent deadlock
+					threadsRepository.discardChanges();
+					ValidationResult result = messageTransaction.importAsUnconfirmed();
 
-			if (result != ValidationResult.OK) {
-				LOGGER.warn(() -> String.format("Unable to send MESSAGE to Bob's trade-bot %s: %s", messageRecipient, result.name()));
-				return ResponseResult.NETWORK_ISSUE;
-			}
+					if (result != ValidationResult.OK) {
+						LOGGER.warn(() -> String.format("Unable to send MESSAGE to Bob's trade-bot %s: %s", messageRecipient, result.name()));
+					}
+				} catch (DataException e) {
+					LOGGER.warn(() -> String.format("Unable to send MESSAGE to Bob's trade-bot %s: %s", messageRecipient, e.getMessage()));
+				}
+			}, "TradeBot response").start();
 		}
 
 		TradeBot.updateTradeBotState(repository, tradeBotData, () -> String.format("Funding P2SH-A %s. Messaged Bob. Waiting for AT-lock", p2shAddress));

src/main/java/org/qortal/controller/tradebot/PirateChainACCTv3TradeBot.java

@@ -523,7 +523,7 @@ public class PirateChainACCTv3TradeBot implements AcctTradeBot {
 			long p2shFee = PirateChain.getInstance().getP2shFee(feeTimestamp);
 			final long minimumAmountA = tradeBotData.getForeignAmount() + p2shFee;
 
-			PirateChainHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+			BitcoinyHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
 
 			switch (htlcStatusA) {
 				case UNFUNDED:
@@ -613,7 +613,7 @@ public class PirateChainACCTv3TradeBot implements AcctTradeBot {
 			long p2shFee = PirateChain.getInstance().getP2shFee(feeTimestamp);
 			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
 
-			PirateChainHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+			BitcoinyHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
 
 			switch (htlcStatusA) {
 				case UNFUNDED:
@@ -751,7 +751,7 @@ public class PirateChainACCTv3TradeBot implements AcctTradeBot {
 		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
 		String receivingAddress = Bech32.encode("zs", receivingAccountInfo);
 
-		PirateChainHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+		BitcoinyHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
 
 		switch (htlcStatusA) {
 			case UNFUNDED:
@@ -822,7 +822,7 @@ public class PirateChainACCTv3TradeBot implements AcctTradeBot {
 		long feeTimestamp = calcFeeTimestamp(lockTimeA, crossChainTradeData.tradeTimeout);
 		long p2shFee = PirateChain.getInstance().getP2shFee(feeTimestamp);
 		long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
-		PirateChainHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
+		BitcoinyHTLC.Status htlcStatusA = PirateChainHTLC.determineHtlcStatus(pirateChain.getBlockchainProvider(), p2shAddress, minimumAmountA);
 
 		switch (htlcStatusA) {
 			case UNFUNDED:

src/main/java/org/qortal/controller/tradebot/TradeBot.java

@@ -96,10 +96,8 @@ public class TradeBot implements Listener {
 		acctTradeBotSuppliers.put(BitcoinACCTv1.class, BitcoinACCTv1TradeBot::getInstance);
 		acctTradeBotSuppliers.put(BitcoinACCTv3.class, BitcoinACCTv3TradeBot::getInstance);
 		acctTradeBotSuppliers.put(LitecoinACCTv1.class, LitecoinACCTv1TradeBot::getInstance);
-		acctTradeBotSuppliers.put(LitecoinACCTv2.class, LitecoinACCTv2TradeBot::getInstance);
 		acctTradeBotSuppliers.put(LitecoinACCTv3.class, LitecoinACCTv3TradeBot::getInstance);
 		acctTradeBotSuppliers.put(DogecoinACCTv1.class, DogecoinACCTv1TradeBot::getInstance);
-		acctTradeBotSuppliers.put(DogecoinACCTv2.class, DogecoinACCTv2TradeBot::getInstance);
 		acctTradeBotSuppliers.put(DogecoinACCTv3.class, DogecoinACCTv3TradeBot::getInstance);
 		acctTradeBotSuppliers.put(DigibyteACCTv3.class, DigibyteACCTv3TradeBot::getInstance);
 		acctTradeBotSuppliers.put(RavencoinACCTv3.class, RavencoinACCTv3TradeBot::getInstance);
@@ -470,9 +468,6 @@ public class TradeBot implements Listener {
 
 		List<TradePresenceData> safeTradePresences = List.copyOf(this.safeAllTradePresencesByPubkey.values());
 
-		if (safeTradePresences.isEmpty())
-			return;
-
 		LOGGER.debug("Broadcasting all {} known trade presences. Next broadcast timestamp: {}",
 				safeTradePresences.size(), nextTradePresenceBroadcastTimestamp
 		);
@@ -639,7 +634,7 @@ public class TradeBot implements Listener {
 		}
 
 		if (newCount > 0) {
-			LOGGER.debug("New trade presences: {}", newCount);
+			LOGGER.debug("New trade presences: {}, all trade presences: {}", newCount, allTradePresencesByPubkey.size());
 			rebuildSafeAllTradePresences();
 		}
 	}

src/main/java/org/qortal/crosschain/Digibyte.java

@@ -134,6 +134,8 @@ public class Digibyte extends Bitcoiny {
 			Context bitcoinjContext = new Context(digibyteNet.getParams());
 
 			instance = new Digibyte(digibyteNet, electrumX, bitcoinjContext, CURRENCY_CODE);
+
+			electrumX.setBlockchain(instance);
 		}
 
 		return instance;

src/main/java/org/qortal/crosschain/DogecoinACCTv2.java

@@ -1,861 +0,0 @@
-package org.qortal.crosschain;
-
-import com.google.common.hash.HashCode;
-import com.google.common.primitives.Bytes;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
-import org.ciyam.at.*;
-import org.qortal.account.Account;
-import org.qortal.asset.Asset;
-import org.qortal.at.QortalFunctionCode;
-import org.qortal.crypto.Crypto;
-import org.qortal.data.at.ATData;
-import org.qortal.data.at.ATStateData;
-import org.qortal.data.crosschain.CrossChainTradeData;
-import org.qortal.data.transaction.MessageTransactionData;
-import org.qortal.repository.DataException;
-import org.qortal.repository.Repository;
-import org.qortal.utils.Base58;
-import org.qortal.utils.BitTwiddling;
-
-import java.nio.ByteBuffer;
-import java.util.Arrays;
-import java.util.List;
-
-import static org.ciyam.at.OpCode.calcOffset;
-
-/**
- * Cross-chain trade AT
- * 
- * <p>
- * <ul>
- * <li>Bob generates Dogecoin & Qortal 'trade' keys
- * 		<ul>
- * 			<li>private key required to sign P2SH redeem tx</li>
- * 			<li>private key could be used to create 'secret' (e.g. double-SHA256)</li>
- * 			<li>encrypted private key could be stored in Qortal AT for access by Bob from any node</li>
- * 		</ul>
- * </li>
- * <li>Bob deploys Qortal AT
- * 		<ul>
- * 		</ul>
- * </li>
- * <li>Alice finds Qortal AT and wants to trade
- * 		<ul>
- * 			<li>Alice generates Dogecoin & Qortal 'trade' keys</li>
- * 			<li>Alice funds Dogecoin P2SH-A</li>
- * 			<li>Alice sends 'offer' MESSAGE to Bob from her Qortal trade address, containing:
- * 				<ul>
- * 					<li>hash-of-secret-A</li>
- * 					<li>her 'trade' Dogecoin PKH</li>
- * 				</ul>
- * 			</li>
- * 		</ul>
- * </li>
- * <li>Bob receives "offer" MESSAGE
- * 		<ul>
- * 			<li>Checks Alice's P2SH-A</li>
- * 			<li>Sends 'trade' MESSAGE to Qortal AT from his trade address, containing:
- * 				<ul>
- * 					<li>Alice's trade Qortal address</li>
- * 					<li>Alice's trade Dogecoin PKH</li>
- * 					<li>hash-of-secret-A</li>
- * 				</ul>
- * 			</li>
- * 		</ul>
- * </li>
- * <li>Alice checks Qortal AT to confirm it's locked to her
- * 		<ul>
- * 			<li>Alice sends 'redeem' MESSAGE to Qortal AT from her trade address, containing:
- * 				<ul>
- * 					<li>secret-A</li>
- * 					<li>Qortal receiving address of her chosing</li>
- * 				</ul>
- * 			</li>
- * 			<li>AT's QORT funds are sent to Qortal receiving address</li>
- * 		</ul>
- * </li>
- * <li>Bob checks AT, extracts secret-A
- * 		<ul>
- * 			<li>Bob redeems P2SH-A using his Dogecoin trade key and secret-A</li>
- * 			<li>P2SH-A DOGE funds end up at Dogecoin address determined by redeem transaction output(s)</li>
- * 		</ul>
- * </li>
- * </ul>
- */
-public class DogecoinACCTv2 implements ACCT {
-
-	private static final Logger LOGGER = LogManager.getLogger(DogecoinACCTv2.class);
-
-	public static final String NAME = DogecoinACCTv2.class.getSimpleName();
-	public static final byte[] CODE_BYTES_HASH = HashCode.fromString("6fff38d6eeb06568a9c879c5628527730319844aa0de53f5f4ffab5506efe885").asBytes(); // SHA256 of AT code bytes
-
-	public static final int SECRET_LENGTH = 32;
-
-	/** <b>Value</b> offset into AT segment where 'mode' variable (long) is stored. (Multiply by MachineState.VALUE_SIZE for byte offset). */
-	private static final int MODE_VALUE_OFFSET = 61;
-	/** <b>Byte</b> offset into AT state data where 'mode' variable (long) is stored. */
-	public static final int MODE_BYTE_OFFSET = MachineState.HEADER_LENGTH + (MODE_VALUE_OFFSET * MachineState.VALUE_SIZE);
-
-	public static class OfferMessageData {
-		public byte[] partnerDogecoinPKH;
-		public byte[] hashOfSecretA;
-		public long lockTimeA;
-	}
-	public static final int OFFER_MESSAGE_LENGTH = 20 /*partnerDogecoinPKH*/ + 20 /*hashOfSecretA*/ + 8 /*lockTimeA*/;
-	public static final int TRADE_MESSAGE_LENGTH = 32 /*partner's Qortal trade address (padded from 25 to 32)*/
-			+ 24 /*partner's Dogecoin PKH (padded from 20 to 24)*/
-			+ 8 /*AT trade timeout (minutes)*/
-			+ 24 /*hash of secret-A (padded from 20 to 24)*/
-			+ 8 /*lockTimeA*/;
-	public static final int REDEEM_MESSAGE_LENGTH = 32 /*secret-A*/ + 32 /*partner's Qortal receiving address padded from 25 to 32*/;
-	public static final int CANCEL_MESSAGE_LENGTH = 32 /*AT creator's Qortal address*/;
-
-	private static DogecoinACCTv2 instance;
-
-	private DogecoinACCTv2() {
-	}
-
-	public static synchronized DogecoinACCTv2 getInstance() {
-		if (instance == null)
-			instance = new DogecoinACCTv2();
-
-		return instance;
-	}
-
-	@Override
-	public byte[] getCodeBytesHash() {
-		return CODE_BYTES_HASH;
-	}
-
-	@Override
-	public int getModeByteOffset() {
-		return MODE_BYTE_OFFSET;
-	}
-
-	@Override
-	public ForeignBlockchain getBlockchain() {
-		return Dogecoin.getInstance();
-	}
-
-	/**
-	 * Returns Qortal AT creation bytes for cross-chain trading AT.
-	 * <p>
-	 * <tt>tradeTimeout</tt> (minutes) is the time window for the trade partner to send the
-	 * 32-byte secret to the AT, before the AT automatically refunds the AT's creator.
-	 * 
-	 * @param creatorTradeAddress AT creator's trade Qortal address
-	 * @param dogecoinPublicKeyHash 20-byte HASH160 of creator's trade Dogecoin public key
-	 * @param qortAmount how much QORT to pay trade partner if they send correct 32-byte secrets to AT
-	 * @param dogecoinAmount how much DOGE the AT creator is expecting to trade
-	 * @param tradeTimeout suggested timeout for entire trade
-	 */
-	public static byte[] buildQortalAT(String creatorTradeAddress, byte[] dogecoinPublicKeyHash, long qortAmount, long dogecoinAmount, int tradeTimeout) {
-		if (dogecoinPublicKeyHash.length != 20)
-			throw new IllegalArgumentException("Dogecoin public key hash should be 20 bytes");
-
-		// Labels for data segment addresses
-		int addrCounter = 0;
-
-		// Constants (with corresponding dataByteBuffer.put*() calls below)
-
-		final int addrCreatorTradeAddress1 = addrCounter++;
-		final int addrCreatorTradeAddress2 = addrCounter++;
-		final int addrCreatorTradeAddress3 = addrCounter++;
-		final int addrCreatorTradeAddress4 = addrCounter++;
-
-		final int addrDogecoinPublicKeyHash = addrCounter;
-		addrCounter += 4;
-
-		final int addrQortAmount = addrCounter++;
-		final int addrDogecoinAmount = addrCounter++;
-		final int addrTradeTimeout = addrCounter++;
-
-		final int addrMessageTxnType = addrCounter++;
-		final int addrExpectedTradeMessageLength = addrCounter++;
-		final int addrExpectedRedeemMessageLength = addrCounter++;
-
-		final int addrCreatorAddressPointer = addrCounter++;
-		final int addrQortalPartnerAddressPointer = addrCounter++;
-		final int addrMessageSenderPointer = addrCounter++;
-
-		final int addrTradeMessagePartnerDogecoinPKHOffset = addrCounter++;
-		final int addrPartnerDogecoinPKHPointer = addrCounter++;
-		final int addrTradeMessageHashOfSecretAOffset = addrCounter++;
-		final int addrHashOfSecretAPointer = addrCounter++;
-
-		final int addrRedeemMessageReceivingAddressOffset = addrCounter++;
-
-		final int addrMessageDataPointer = addrCounter++;
-		final int addrMessageDataLength = addrCounter++;
-
-		final int addrPartnerReceivingAddressPointer = addrCounter++;
-
-		final int addrEndOfConstants = addrCounter;
-
-		// Variables
-
-		final int addrCreatorAddress1 = addrCounter++;
-		final int addrCreatorAddress2 = addrCounter++;
-		final int addrCreatorAddress3 = addrCounter++;
-		final int addrCreatorAddress4 = addrCounter++;
-
-		final int addrQortalPartnerAddress1 = addrCounter++;
-		final int addrQortalPartnerAddress2 = addrCounter++;
-		final int addrQortalPartnerAddress3 = addrCounter++;
-		final int addrQortalPartnerAddress4 = addrCounter++;
-
-		final int addrLockTimeA = addrCounter++;
-		final int addrRefundTimeout = addrCounter++;
-		final int addrRefundTimestamp = addrCounter++;
-		final int addrLastTxnTimestamp = addrCounter++;
-		final int addrBlockTimestamp = addrCounter++;
-		final int addrTxnType = addrCounter++;
-		final int addrResult = addrCounter++;
-
-		final int addrMessageSender1 = addrCounter++;
-		final int addrMessageSender2 = addrCounter++;
-		final int addrMessageSender3 = addrCounter++;
-		final int addrMessageSender4 = addrCounter++;
-
-		final int addrMessageLength = addrCounter++;
-
-		final int addrMessageData = addrCounter;
-		addrCounter += 4;
-
-		final int addrHashOfSecretA = addrCounter;
-		addrCounter += 4;
-
-		final int addrPartnerDogecoinPKH = addrCounter;
-		addrCounter += 4;
-
-		final int addrPartnerReceivingAddress = addrCounter;
-		addrCounter += 4;
-
-		final int addrMode = addrCounter++;
-		assert addrMode == MODE_VALUE_OFFSET : String.format("addrMode %d does not match MODE_VALUE_OFFSET %d", addrMode, MODE_VALUE_OFFSET);
-
-		// Data segment
-		ByteBuffer dataByteBuffer = ByteBuffer.allocate(addrCounter * MachineState.VALUE_SIZE);
-
-		// AT creator's trade Qortal address, decoded from Base58
-		assert dataByteBuffer.position() == addrCreatorTradeAddress1 * MachineState.VALUE_SIZE : "addrCreatorTradeAddress1 incorrect";
-		byte[] creatorTradeAddressBytes = Base58.decode(creatorTradeAddress);
-		dataByteBuffer.put(Bytes.ensureCapacity(creatorTradeAddressBytes, 32, 0));
-
-		// Dogecoin public key hash
-		assert dataByteBuffer.position() == addrDogecoinPublicKeyHash * MachineState.VALUE_SIZE : "addrDogecoinPublicKeyHash incorrect";
-		dataByteBuffer.put(Bytes.ensureCapacity(dogecoinPublicKeyHash, 32, 0));
-
-		// Redeem Qort amount
-		assert dataByteBuffer.position() == addrQortAmount * MachineState.VALUE_SIZE : "addrQortAmount incorrect";
-		dataByteBuffer.putLong(qortAmount);
-
-		// Expected Dogecoin amount
-		assert dataByteBuffer.position() == addrDogecoinAmount * MachineState.VALUE_SIZE : "addrDogecoinAmount incorrect";
-		dataByteBuffer.putLong(dogecoinAmount);
-
-		// Suggested trade timeout (minutes)
-		assert dataByteBuffer.position() == addrTradeTimeout * MachineState.VALUE_SIZE : "addrTradeTimeout incorrect";
-		dataByteBuffer.putLong(tradeTimeout);
-
-		// We're only interested in MESSAGE transactions
-		assert dataByteBuffer.position() == addrMessageTxnType * MachineState.VALUE_SIZE : "addrMessageTxnType incorrect";
-		dataByteBuffer.putLong(API.ATTransactionType.MESSAGE.value);
-
-		// Expected length of 'trade' MESSAGE data from AT creator
-		assert dataByteBuffer.position() == addrExpectedTradeMessageLength * MachineState.VALUE_SIZE : "addrExpectedTradeMessageLength incorrect";
-		dataByteBuffer.putLong(TRADE_MESSAGE_LENGTH);
-
-		// Expected length of 'redeem' MESSAGE data from trade partner
-		assert dataByteBuffer.position() == addrExpectedRedeemMessageLength * MachineState.VALUE_SIZE : "addrExpectedRedeemMessageLength incorrect";
-		dataByteBuffer.putLong(REDEEM_MESSAGE_LENGTH);
-
-		// Index into data segment of AT creator's address, used by GET_B_IND
-		assert dataByteBuffer.position() == addrCreatorAddressPointer * MachineState.VALUE_SIZE : "addrCreatorAddressPointer incorrect";
-		dataByteBuffer.putLong(addrCreatorAddress1);
-
-		// Index into data segment of partner's Qortal address, used by SET_B_IND
-		assert dataByteBuffer.position() == addrQortalPartnerAddressPointer * MachineState.VALUE_SIZE : "addrQortalPartnerAddressPointer incorrect";
-		dataByteBuffer.putLong(addrQortalPartnerAddress1);
-
-		// Index into data segment of (temporary) transaction's sender's address, used by GET_B_IND
-		assert dataByteBuffer.position() == addrMessageSenderPointer * MachineState.VALUE_SIZE : "addrMessageSenderPointer incorrect";
-		dataByteBuffer.putLong(addrMessageSender1);
-
-		// Offset into 'trade' MESSAGE data payload for extracting partner's Dogecoin PKH
-		assert dataByteBuffer.position() == addrTradeMessagePartnerDogecoinPKHOffset * MachineState.VALUE_SIZE : "addrTradeMessagePartnerDogecoinPKHOffset incorrect";
-		dataByteBuffer.putLong(32L);
-
-		// Index into data segment of partner's Dogecoin PKH, used by GET_B_IND
-		assert dataByteBuffer.position() == addrPartnerDogecoinPKHPointer * MachineState.VALUE_SIZE : "addrPartnerDogecoinPKHPointer incorrect";
-		dataByteBuffer.putLong(addrPartnerDogecoinPKH);
-
-		// Offset into 'trade' MESSAGE data payload for extracting hash-of-secret-A
-		assert dataByteBuffer.position() == addrTradeMessageHashOfSecretAOffset * MachineState.VALUE_SIZE : "addrTradeMessageHashOfSecretAOffset incorrect";
-		dataByteBuffer.putLong(64L);
-
-		// Index into data segment to hash of secret A, used by GET_B_IND
-		assert dataByteBuffer.position() == addrHashOfSecretAPointer * MachineState.VALUE_SIZE : "addrHashOfSecretAPointer incorrect";
-		dataByteBuffer.putLong(addrHashOfSecretA);
-
-		// Offset into 'redeem' MESSAGE data payload for extracting Qortal receiving address
-		assert dataByteBuffer.position() == addrRedeemMessageReceivingAddressOffset * MachineState.VALUE_SIZE : "addrRedeemMessageReceivingAddressOffset incorrect";
-		dataByteBuffer.putLong(32L);
-
-		// Source location and length for hashing any passed secret
-		assert dataByteBuffer.position() == addrMessageDataPointer * MachineState.VALUE_SIZE : "addrMessageDataPointer incorrect";
-		dataByteBuffer.putLong(addrMessageData);
-		assert dataByteBuffer.position() == addrMessageDataLength * MachineState.VALUE_SIZE : "addrMessageDataLength incorrect";
-		dataByteBuffer.putLong(32L);
-
-		// Pointer into data segment of where to save partner's receiving Qortal address, used by GET_B_IND
-		assert dataByteBuffer.position() == addrPartnerReceivingAddressPointer * MachineState.VALUE_SIZE : "addrPartnerReceivingAddressPointer incorrect";
-		dataByteBuffer.putLong(addrPartnerReceivingAddress);
-
-		assert dataByteBuffer.position() == addrEndOfConstants * MachineState.VALUE_SIZE : "dataByteBuffer position not at end of constants";
-
-		// Code labels
-		Integer labelRefund = null;
-
-		Integer labelTradeTxnLoop = null;
-		Integer labelCheckTradeTxn = null;
-		Integer labelCheckCancelTxn = null;
-		Integer labelNotTradeNorCancelTxn = null;
-		Integer labelCheckNonRefundTradeTxn = null;
-		Integer labelTradeTxnExtract = null;
-		Integer labelRedeemTxnLoop = null;
-		Integer labelCheckRedeemTxn = null;
-		Integer labelCheckRedeemTxnSender = null;
-		Integer labelPayout = null;
-
-		ByteBuffer codeByteBuffer = ByteBuffer.allocate(768);
-
-		// Two-pass version
-		for (int pass = 0; pass < 2; ++pass) {
-			codeByteBuffer.clear();
-
-			try {
-				/* Initialization */
-
-				/* NOP - to ensure DOGECOIN ACCT is unique */
-				codeByteBuffer.put(OpCode.NOP.compile());
-
-				// Use AT creation 'timestamp' as starting point for finding transactions sent to AT
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_CREATION_TIMESTAMP, addrLastTxnTimestamp));
-
-				// Load B register with AT creator's address so we can save it into addrCreatorAddress1-4
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_CREATOR_INTO_B));
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrCreatorAddressPointer));
-
-				// Set restart position to after this opcode
-				codeByteBuffer.put(OpCode.SET_PCS.compile());
-
-				/* Loop, waiting for message from AT creator's trade address containing trade partner details, or AT owner's address to cancel offer */
-
-				/* Transaction processing loop */
-				labelTradeTxnLoop = codeByteBuffer.position();
-
-				/* Sleep until message arrives */
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.SLEEP_UNTIL_MESSAGE.value, addrLastTxnTimestamp));
-
-				// Find next transaction (if any) to this AT since the last one (referenced by addrLastTxnTimestamp)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PUT_TX_AFTER_TIMESTAMP_INTO_A, addrLastTxnTimestamp));
-				// If no transaction found, A will be zero. If A is zero, set addrResult to 1, otherwise 0.
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.CHECK_A_IS_ZERO, addrResult));
-				// If addrResult is zero (i.e. A is non-zero, transaction was found) then go check transaction
-				codeByteBuffer.put(OpCode.BZR_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelCheckTradeTxn)));
-				// Stop and wait for next block
-				codeByteBuffer.put(OpCode.STP_IMD.compile());
-
-				/* Check transaction */
-				labelCheckTradeTxn = codeByteBuffer.position();
-
-				// Update our 'last found transaction's timestamp' using 'timestamp' from transaction
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TIMESTAMP_FROM_TX_IN_A, addrLastTxnTimestamp));
-				// Extract transaction type (message/payment) from transaction and save type in addrTxnType
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TYPE_FROM_TX_IN_A, addrTxnType));
-				// If transaction type is not MESSAGE type then go look for another transaction
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrTxnType, addrMessageTxnType, calcOffset(codeByteBuffer, labelTradeTxnLoop)));
-
-				/* Check transaction's sender. We're expecting AT creator's trade address for 'trade' message, or AT creator's own address for 'cancel' message. */
-
-				// Extract sender address from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_ADDRESS_FROM_TX_IN_A_INTO_B));
-				// Save B register into data segment starting at addrMessageSender1 (as pointed to by addrMessageSenderPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageSenderPointer));
-				// Compare each part of message sender's address with AT creator's trade address. If they don't match, check for cancel situation.
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrCreatorTradeAddress1, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrCreatorTradeAddress2, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrCreatorTradeAddress3, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrCreatorTradeAddress4, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
-				// Message sender's address matches AT creator's trade address so go process 'trade' message
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelCheckNonRefundTradeTxn == null ? 0 : labelCheckNonRefundTradeTxn));
-
-				/* Checking message sender for possible cancel message */
-				labelCheckCancelTxn = codeByteBuffer.position();
-
-				// Compare each part of message sender's address with AT creator's address. If they don't match, look for another transaction.
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrCreatorAddress1, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrCreatorAddress2, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrCreatorAddress3, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrCreatorAddress4, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
-				// Partner address is AT creator's address, so cancel offer and finish.
-				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.CANCELLED.value));
-				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
-				codeByteBuffer.put(OpCode.FIN_IMD.compile());
-
-				/* Not trade nor cancel message */
-				labelNotTradeNorCancelTxn = codeByteBuffer.position();
-
-				// Loop to find another transaction
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelTradeTxnLoop == null ? 0 : labelTradeTxnLoop));
-
-				/* Possible switch-to-trade-mode message */
-				labelCheckNonRefundTradeTxn = codeByteBuffer.position();
-
-				// Check 'trade' message we received has expected number of message bytes
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(QortalFunctionCode.GET_MESSAGE_LENGTH_FROM_TX_IN_A.value, addrMessageLength));
-				// If message length matches, branch to info extraction code
-				codeByteBuffer.put(OpCode.BEQ_DAT.compile(addrMessageLength, addrExpectedTradeMessageLength, calcOffset(codeByteBuffer, labelTradeTxnExtract)));
-				// Message length didn't match - go back to finding another 'trade' MESSAGE transaction
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelTradeTxnLoop == null ? 0 : labelTradeTxnLoop));
-
-				/* Extracting info from 'trade' MESSAGE transaction */
-				labelTradeTxnExtract = codeByteBuffer.position();
-
-				// Extract message from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_MESSAGE_FROM_TX_IN_A_INTO_B));
-				// Save B register into data segment starting at addrQortalPartnerAddress1 (as pointed to by addrQortalPartnerAddressPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrQortalPartnerAddressPointer));
-
-				// Extract trade partner's Dogecoin public key hash (PKH) from message into B
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessagePartnerDogecoinPKHOffset));
-				// Store partner's Dogecoin PKH (we only really use values from B1-B3)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerDogecoinPKHPointer));
-				// Extract AT trade timeout (minutes) (from B4)
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_B4, addrRefundTimeout));
-
-				// Grab next 32 bytes
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessageHashOfSecretAOffset));
-
-				// Extract hash-of-secret-A (we only really use values from B1-B3)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrHashOfSecretAPointer));
-				// Extract lockTime-A (from B4)
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_B4, addrLockTimeA));
-
-				// Calculate trade timeout refund 'timestamp' by adding addrRefundTimeout minutes to this transaction's 'timestamp', then save into addrRefundTimestamp
-				codeByteBuffer.put(OpCode.EXT_FUN_RET_DAT_2.compile(FunctionCode.ADD_MINUTES_TO_TIMESTAMP, addrRefundTimestamp, addrLastTxnTimestamp, addrRefundTimeout));
-
-				/* We are in 'trade mode' */
-				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.TRADING.value));
-
-				// Set restart position to after this opcode
-				codeByteBuffer.put(OpCode.SET_PCS.compile());
-
-				/* Loop, waiting for trade timeout or 'redeem' MESSAGE from Qortal trade partner */
-
-				// Fetch current block 'timestamp'
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_BLOCK_TIMESTAMP, addrBlockTimestamp));
-				// If we're not past refund 'timestamp' then look for next transaction
-				codeByteBuffer.put(OpCode.BLT_DAT.compile(addrBlockTimestamp, addrRefundTimestamp, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-				// We're past refund 'timestamp' so go refund everything back to AT creator
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRefund == null ? 0 : labelRefund));
-
-				/* Transaction processing loop */
-				labelRedeemTxnLoop = codeByteBuffer.position();
-
-				/* Sleep until message arrives */
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.SLEEP_UNTIL_MESSAGE.value, addrLastTxnTimestamp));
-
-				// Find next transaction to this AT since the last one (if any)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PUT_TX_AFTER_TIMESTAMP_INTO_A, addrLastTxnTimestamp));
-				// If no transaction found, A will be zero. If A is zero, set addrComparator to 1, otherwise 0.
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.CHECK_A_IS_ZERO, addrResult));
-				// If addrResult is zero (i.e. A is non-zero, transaction was found) then go check transaction
-				codeByteBuffer.put(OpCode.BZR_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelCheckRedeemTxn)));
-				// Stop and wait for next block
-				codeByteBuffer.put(OpCode.STP_IMD.compile());
-
-				/* Check transaction */
-				labelCheckRedeemTxn = codeByteBuffer.position();
-
-				// Update our 'last found transaction's timestamp' using 'timestamp' from transaction
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TIMESTAMP_FROM_TX_IN_A, addrLastTxnTimestamp));
-				// Extract transaction type (message/payment) from transaction and save type in addrTxnType
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TYPE_FROM_TX_IN_A, addrTxnType));
-				// If transaction type is not MESSAGE type then go look for another transaction
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrTxnType, addrMessageTxnType, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-
-				/* Check message payload length */
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(QortalFunctionCode.GET_MESSAGE_LENGTH_FROM_TX_IN_A.value, addrMessageLength));
-				// If message length matches, branch to sender checking code
-				codeByteBuffer.put(OpCode.BEQ_DAT.compile(addrMessageLength, addrExpectedRedeemMessageLength, calcOffset(codeByteBuffer, labelCheckRedeemTxnSender)));
-				// Message length didn't match - go back to finding another 'redeem' MESSAGE transaction
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRedeemTxnLoop == null ? 0 : labelRedeemTxnLoop));
-
-				/* Check transaction's sender */
-				labelCheckRedeemTxnSender = codeByteBuffer.position();
-
-				// Extract sender address from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_ADDRESS_FROM_TX_IN_A_INTO_B));
-				// Save B register into data segment starting at addrMessageSender1 (as pointed to by addrMessageSenderPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageSenderPointer));
-				// Compare each part of transaction's sender's address with expected address. If they don't match, look for another transaction.
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrQortalPartnerAddress1, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrQortalPartnerAddress2, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrQortalPartnerAddress3, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrQortalPartnerAddress4, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-
-				/* Check 'secret-A' in transaction's message */
-
-				// Extract secret-A from first 32 bytes of message from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_MESSAGE_FROM_TX_IN_A_INTO_B));
-				// Save B register into data segment starting at addrMessageData (as pointed to by addrMessageDataPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageDataPointer));
-				// Load B register with expected hash result (as pointed to by addrHashOfSecretAPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.SET_B_IND, addrHashOfSecretAPointer));
-				// Perform HASH160 using source data at addrMessageData. (Location and length specified via addrMessageDataPointer and addrMessageDataLength).
-				// Save the equality result (1 if they match, 0 otherwise) into addrResult.
-				codeByteBuffer.put(OpCode.EXT_FUN_RET_DAT_2.compile(FunctionCode.CHECK_HASH160_WITH_B, addrResult, addrMessageDataPointer, addrMessageDataLength));
-				// If hashes don't match, addrResult will be zero so go find another transaction
-				codeByteBuffer.put(OpCode.BNZ_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelPayout)));
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRedeemTxnLoop == null ? 0 : labelRedeemTxnLoop));
-
-				/* Success! Pay arranged amount to receiving address */
-				labelPayout = codeByteBuffer.position();
-
-				// Extract Qortal receiving address from next 32 bytes of message from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrRedeemMessageReceivingAddressOffset));
-				// Save B register into data segment starting at addrPartnerReceivingAddress (as pointed to by addrPartnerReceivingAddressPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerReceivingAddressPointer));
-				// Pay AT's balance to receiving address
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PAY_TO_ADDRESS_IN_B, addrQortAmount));
-				// Set redeemed mode
-				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.REDEEMED.value));
-				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
-				codeByteBuffer.put(OpCode.FIN_IMD.compile());
-
-				// Fall-through to refunding any remaining balance back to AT creator
-
-				/* Refund balance back to AT creator */
-				labelRefund = codeByteBuffer.position();
-
-				// Set refunded mode
-				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.REFUNDED.value));
-				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
-				codeByteBuffer.put(OpCode.FIN_IMD.compile());
-			} catch (CompilationException e) {
-				throw new IllegalStateException("Unable to compile DOGE-QORT ACCT?", e);
-			}
-		}
-
-		codeByteBuffer.flip();
-
-		byte[] codeBytes = new byte[codeByteBuffer.limit()];
-		codeByteBuffer.get(codeBytes);
-
-		assert Arrays.equals(Crypto.digest(codeBytes), DogecoinACCTv2.CODE_BYTES_HASH)
-			: String.format("BTCACCT.CODE_BYTES_HASH mismatch: expected %s, actual %s", HashCode.fromBytes(CODE_BYTES_HASH), HashCode.fromBytes(Crypto.digest(codeBytes)));
-
-		final short ciyamAtVersion = 2;
-		final short numCallStackPages = 0;
-		final short numUserStackPages = 0;
-		final long minActivationAmount = 0L;
-
-		return MachineState.toCreationBytes(ciyamAtVersion, codeBytes, dataByteBuffer.array(), numCallStackPages, numUserStackPages, minActivationAmount);
-	}
-
-	/**
-	 * Returns CrossChainTradeData with useful info extracted from AT.
-	 */
-	@Override
-	public CrossChainTradeData populateTradeData(Repository repository, ATData atData) throws DataException {
-		ATStateData atStateData = repository.getATRepository().getLatestATState(atData.getATAddress());
-		return populateTradeData(repository, atData.getCreatorPublicKey(), atData.getCreation(), atStateData);
-	}
-
-	/**
-	 * Returns CrossChainTradeData with useful info extracted from AT.
-	 */
-	@Override
-	public CrossChainTradeData populateTradeData(Repository repository, ATStateData atStateData) throws DataException {
-		ATData atData = repository.getATRepository().fromATAddress(atStateData.getATAddress());
-		return populateTradeData(repository, atData.getCreatorPublicKey(), atData.getCreation(), atStateData);
-	}
-
-	/**
-	 * Returns CrossChainTradeData with useful info extracted from AT.
-	 */
-	public CrossChainTradeData populateTradeData(Repository repository, byte[] creatorPublicKey, long creationTimestamp, ATStateData atStateData) throws DataException {
-		byte[] addressBytes = new byte[25]; // for general use
-		String atAddress = atStateData.getATAddress();
-
-		CrossChainTradeData tradeData = new CrossChainTradeData();
-
-		tradeData.foreignBlockchain = SupportedBlockchain.DOGECOIN.name();
-		tradeData.acctName = NAME;
-
-		tradeData.qortalAtAddress = atAddress;
-		tradeData.qortalCreator = Crypto.toAddress(creatorPublicKey);
-		tradeData.creationTimestamp = creationTimestamp;
-
-		Account atAccount = new Account(repository, atAddress);
-		tradeData.qortBalance = atAccount.getConfirmedBalance(Asset.QORT);
-
-		byte[] stateData = atStateData.getStateData();
-		ByteBuffer dataByteBuffer = ByteBuffer.wrap(stateData);
-		dataByteBuffer.position(MachineState.HEADER_LENGTH);
-
-		/* Constants */
-
-		// Skip creator's trade address
-		dataByteBuffer.get(addressBytes);
-		tradeData.qortalCreatorTradeAddress = Base58.encode(addressBytes);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - addressBytes.length);
-
-		// Creator's Dogecoin/foreign public key hash
-		tradeData.creatorForeignPKH = new byte[20];
-		dataByteBuffer.get(tradeData.creatorForeignPKH);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - tradeData.creatorForeignPKH.length); // skip to 32 bytes
-
-		// We don't use secret-B
-		tradeData.hashOfSecretB = null;
-
-		// Redeem payout
-		tradeData.qortAmount = dataByteBuffer.getLong();
-
-		// Expected DOGE amount
-		tradeData.expectedForeignAmount = dataByteBuffer.getLong();
-
-		// Trade timeout
-		tradeData.tradeTimeout = (int) dataByteBuffer.getLong();
-
-		// Skip MESSAGE transaction type
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip expected 'trade' message length
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip expected 'redeem' message length
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to creator's address
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to partner's Qortal trade address
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to message sender
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip 'trade' message data offset for partner's Dogecoin PKH
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to partner's Dogecoin PKH
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip 'trade' message data offset for hash-of-secret-A
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to hash-of-secret-A
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip 'redeem' message data offset for partner's Qortal receiving address
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to message data
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip message data length
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to partner's receiving address
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		/* End of constants / begin variables */
-
-		// Skip AT creator's address
-		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
-
-		// Partner's trade address (if present)
-		dataByteBuffer.get(addressBytes);
-		String qortalRecipient = Base58.encode(addressBytes);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - addressBytes.length);
-
-		// Potential lockTimeA (if in trade mode)
-		int lockTimeA = (int) dataByteBuffer.getLong();
-
-		// AT refund timeout (probably only useful for debugging)
-		int refundTimeout = (int) dataByteBuffer.getLong();
-
-		// Trade-mode refund timestamp (AT 'timestamp' converted to Qortal block height)
-		long tradeRefundTimestamp = dataByteBuffer.getLong();
-
-		// Skip last transaction timestamp
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip block timestamp
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip transaction type
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip temporary result
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip temporary message sender
-		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
-
-		// Skip message length
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip temporary message data
-		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
-
-		// Potential hash160 of secret A
-		byte[] hashOfSecretA = new byte[20];
-		dataByteBuffer.get(hashOfSecretA);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - hashOfSecretA.length); // skip to 32 bytes
-
-		// Potential partner's Dogecoin PKH
-		byte[] partnerDogecoinPKH = new byte[20];
-		dataByteBuffer.get(partnerDogecoinPKH);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerDogecoinPKH.length); // skip to 32 bytes
-
-		// Partner's receiving address (if present)
-		byte[] partnerReceivingAddress = new byte[25];
-		dataByteBuffer.get(partnerReceivingAddress);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerReceivingAddress.length); // skip to 32 bytes
-
-		// Trade AT's 'mode'
-		long modeValue = dataByteBuffer.getLong();
-		AcctMode mode = AcctMode.valueOf((int) (modeValue & 0xffL));
-
-		/* End of variables */
-
-		if (mode != null && mode != AcctMode.OFFERING) {
-			tradeData.mode = mode;
-			tradeData.refundTimeout = refundTimeout;
-			tradeData.tradeRefundHeight = new Timestamp(tradeRefundTimestamp).blockHeight;
-			tradeData.qortalPartnerAddress = qortalRecipient;
-			tradeData.hashOfSecretA = hashOfSecretA;
-			tradeData.partnerForeignPKH = partnerDogecoinPKH;
-			tradeData.lockTimeA = lockTimeA;
-
-			if (mode == AcctMode.REDEEMED)
-				tradeData.qortalPartnerReceivingAddress = Base58.encode(partnerReceivingAddress);
-		} else {
-			tradeData.mode = AcctMode.OFFERING;
-		}
-
-		tradeData.duplicateDeprecated();
-
-		return tradeData;
-	}
-
-	/** Returns 'offer' MESSAGE payload for trade partner to send to AT creator's trade address. */
-	public static byte[] buildOfferMessage(byte[] partnerBitcoinPKH, byte[] hashOfSecretA, int lockTimeA) {
-		byte[] lockTimeABytes = BitTwiddling.toBEByteArray((long) lockTimeA);
-		return Bytes.concat(partnerBitcoinPKH, hashOfSecretA, lockTimeABytes);
-	}
-
-	/** Returns info extracted from 'offer' MESSAGE payload sent by trade partner to AT creator's trade address, or null if not valid. */
-	public static OfferMessageData extractOfferMessageData(byte[] messageData) {
-		if (messageData == null || messageData.length != OFFER_MESSAGE_LENGTH)
-			return null;
-
-		OfferMessageData offerMessageData = new OfferMessageData();
-		offerMessageData.partnerDogecoinPKH = Arrays.copyOfRange(messageData, 0, 20);
-		offerMessageData.hashOfSecretA = Arrays.copyOfRange(messageData, 20, 40);
-		offerMessageData.lockTimeA = BitTwiddling.longFromBEBytes(messageData, 40);
-
-		return offerMessageData;
-	}
-
-	/** Returns 'trade' MESSAGE payload for AT creator to send to AT. */
-	public static byte[] buildTradeMessage(String partnerQortalTradeAddress, byte[] partnerBitcoinPKH, byte[] hashOfSecretA, int lockTimeA, int refundTimeout) {
-		byte[] data = new byte[TRADE_MESSAGE_LENGTH];
-		byte[] partnerQortalAddressBytes = Base58.decode(partnerQortalTradeAddress);
-		byte[] lockTimeABytes = BitTwiddling.toBEByteArray((long) lockTimeA);
-		byte[] refundTimeoutBytes = BitTwiddling.toBEByteArray((long) refundTimeout);
-
-		System.arraycopy(partnerQortalAddressBytes, 0, data, 0, partnerQortalAddressBytes.length);
-		System.arraycopy(partnerBitcoinPKH, 0, data, 32, partnerBitcoinPKH.length);
-		System.arraycopy(refundTimeoutBytes, 0, data, 56, refundTimeoutBytes.length);
-		System.arraycopy(hashOfSecretA, 0, data, 64, hashOfSecretA.length);
-		System.arraycopy(lockTimeABytes, 0, data, 88, lockTimeABytes.length);
-
-		return data;
-	}
-
-	/** Returns 'cancel' MESSAGE payload for AT creator to cancel trade AT. */
-	@Override
-	public byte[] buildCancelMessage(String creatorQortalAddress) {
-		byte[] data = new byte[CANCEL_MESSAGE_LENGTH];
-		byte[] creatorQortalAddressBytes = Base58.decode(creatorQortalAddress);
-
-		System.arraycopy(creatorQortalAddressBytes, 0, data, 0, creatorQortalAddressBytes.length);
-
-		return data;
-	}
-
-	/** Returns 'redeem' MESSAGE payload for trade partner to send to AT. */
-	public static byte[] buildRedeemMessage(byte[] secretA, String qortalReceivingAddress) {
-		byte[] data = new byte[REDEEM_MESSAGE_LENGTH];
-		byte[] qortalReceivingAddressBytes = Base58.decode(qortalReceivingAddress);
-
-		System.arraycopy(secretA, 0, data, 0, secretA.length);
-		System.arraycopy(qortalReceivingAddressBytes, 0, data, 32, qortalReceivingAddressBytes.length);
-
-		return data;
-	}
-
-	/** Returns refund timeout (minutes) based on trade partner's 'offer' MESSAGE timestamp and P2SH-A locktime. */
-	public static int calcRefundTimeout(long offerMessageTimestamp, int lockTimeA) {
-		// refund should be triggered halfway between offerMessageTimestamp and lockTimeA
-		return (int) ((lockTimeA - (offerMessageTimestamp / 1000L)) / 2L / 60L);
-	}
-
-	@Override
-	public byte[] findSecretA(Repository repository, CrossChainTradeData crossChainTradeData) throws DataException {
-		String atAddress = crossChainTradeData.qortalAtAddress;
-		String redeemerAddress = crossChainTradeData.qortalPartnerAddress;
-
-		// We don't have partner's public key so we check every message to AT
-		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(null, atAddress, null, null, null);
-		if (messageTransactionsData == null)
-			return null;
-
-		// Find 'redeem' message
-		for (MessageTransactionData messageTransactionData : messageTransactionsData) {
-			// Check message payload type/encryption
-			if (messageTransactionData.isText() || messageTransactionData.isEncrypted())
-				continue;
-
-			// Check message payload size
-			byte[] messageData = messageTransactionData.getData();
-			if (messageData.length != REDEEM_MESSAGE_LENGTH)
-				// Wrong payload length
-				continue;
-
-			// Check sender
-			if (!Crypto.toAddress(messageTransactionData.getSenderPublicKey()).equals(redeemerAddress))
-				// Wrong sender;
-				continue;
-
-			// Extract secretA
-			byte[] secretA = new byte[32];
-			System.arraycopy(messageData, 0, secretA, 0, secretA.length);
-
-			byte[] hashOfSecretA = Crypto.hash160(secretA);
-			if (!Arrays.equals(hashOfSecretA, crossChainTradeData.hashOfSecretA))
-				continue;
-
-			return secretA;
-		}
-
-		return null;
-	}
-
-}

src/main/java/org/qortal/crosschain/ElectrumX.java

@@ -40,7 +40,7 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 	private static final String VERBOSE_TRANSACTIONS_UNSUPPORTED_MESSAGE = "verbose transactions are currently unsupported";
 
 	private static final int RESPONSE_TIME_READINGS = 5;
-	private static final long MAX_AVG_RESPONSE_TIME = 500L; // ms
+	private static final long MAX_AVG_RESPONSE_TIME = 1000L; // ms
 
 	public static class Server {
 		String hostname;

src/main/java/org/qortal/crosschain/LitecoinACCTv2.java

@@ -1,854 +0,0 @@
-package org.qortal.crosschain;
-
-import com.google.common.hash.HashCode;
-import com.google.common.primitives.Bytes;
-import org.ciyam.at.*;
-import org.qortal.account.Account;
-import org.qortal.asset.Asset;
-import org.qortal.at.QortalFunctionCode;
-import org.qortal.crypto.Crypto;
-import org.qortal.data.at.ATData;
-import org.qortal.data.at.ATStateData;
-import org.qortal.data.crosschain.CrossChainTradeData;
-import org.qortal.data.transaction.MessageTransactionData;
-import org.qortal.repository.DataException;
-import org.qortal.repository.Repository;
-import org.qortal.utils.Base58;
-import org.qortal.utils.BitTwiddling;
-
-import java.nio.ByteBuffer;
-import java.util.Arrays;
-import java.util.List;
-
-import static org.ciyam.at.OpCode.calcOffset;
-
-/**
- * Cross-chain trade AT
- * 
- * <p>
- * <ul>
- * <li>Bob generates Litecoin & Qortal 'trade' keys
- * 		<ul>
- * 			<li>private key required to sign P2SH redeem tx</li>
- * 			<li>private key could be used to create 'secret' (e.g. double-SHA256)</li>
- * 			<li>encrypted private key could be stored in Qortal AT for access by Bob from any node</li>
- * 		</ul>
- * </li>
- * <li>Bob deploys Qortal AT
- * 		<ul>
- * 		</ul>
- * </li>
- * <li>Alice finds Qortal AT and wants to trade
- * 		<ul>
- * 			<li>Alice generates Litecoin & Qortal 'trade' keys</li>
- * 			<li>Alice funds Litecoin P2SH-A</li>
- * 			<li>Alice sends 'offer' MESSAGE to Bob from her Qortal trade address, containing:
- * 				<ul>
- * 					<li>hash-of-secret-A</li>
- * 					<li>her 'trade' Litecoin PKH</li>
- * 				</ul>
- * 			</li>
- * 		</ul>
- * </li>
- * <li>Bob receives "offer" MESSAGE
- * 		<ul>
- * 			<li>Checks Alice's P2SH-A</li>
- * 			<li>Sends 'trade' MESSAGE to Qortal AT from his trade address, containing:
- * 				<ul>
- * 					<li>Alice's trade Qortal address</li>
- * 					<li>Alice's trade Litecoin PKH</li>
- * 					<li>hash-of-secret-A</li>
- * 				</ul>
- * 			</li>
- * 		</ul>
- * </li>
- * <li>Alice checks Qortal AT to confirm it's locked to her
- * 		<ul>
- * 			<li>Alice sends 'redeem' MESSAGE to Qortal AT from her trade address, containing:
- * 				<ul>
- * 					<li>secret-A</li>
- * 					<li>Qortal receiving address of her chosing</li>
- * 				</ul>
- * 			</li>
- * 			<li>AT's QORT funds are sent to Qortal receiving address</li>
- * 		</ul>
- * </li>
- * <li>Bob checks AT, extracts secret-A
- * 		<ul>
- * 			<li>Bob redeems P2SH-A using his Litecoin trade key and secret-A</li>
- * 			<li>P2SH-A LTC funds end up at Litecoin address determined by redeem transaction output(s)</li>
- * 		</ul>
- * </li>
- * </ul>
- */
-public class LitecoinACCTv2 implements ACCT {
-
-	public static final String NAME = LitecoinACCTv2.class.getSimpleName();
-	public static final byte[] CODE_BYTES_HASH = HashCode.fromString("d5ea386a41441180c854ca8d7bbc620bfd53a97df2650a2b162b52324caf6e19").asBytes(); // SHA256 of AT code bytes
-
-	public static final int SECRET_LENGTH = 32;
-
-	/** <b>Value</b> offset into AT segment where 'mode' variable (long) is stored. (Multiply by MachineState.VALUE_SIZE for byte offset). */
-	private static final int MODE_VALUE_OFFSET = 61;
-	/** <b>Byte</b> offset into AT state data where 'mode' variable (long) is stored. */
-	public static final int MODE_BYTE_OFFSET = MachineState.HEADER_LENGTH + (MODE_VALUE_OFFSET * MachineState.VALUE_SIZE);
-
-	public static class OfferMessageData {
-		public byte[] partnerLitecoinPKH;
-		public byte[] hashOfSecretA;
-		public long lockTimeA;
-	}
-	public static final int OFFER_MESSAGE_LENGTH = 20 /*partnerLitecoinPKH*/ + 20 /*hashOfSecretA*/ + 8 /*lockTimeA*/;
-	public static final int TRADE_MESSAGE_LENGTH = 32 /*partner's Qortal trade address (padded from 25 to 32)*/
-			+ 24 /*partner's Litecoin PKH (padded from 20 to 24)*/
-			+ 8 /*AT trade timeout (minutes)*/
-			+ 24 /*hash of secret-A (padded from 20 to 24)*/
-			+ 8 /*lockTimeA*/;
-	public static final int REDEEM_MESSAGE_LENGTH = 32 /*secret-A*/ + 32 /*partner's Qortal receiving address padded from 25 to 32*/;
-	public static final int CANCEL_MESSAGE_LENGTH = 32 /*AT creator's Qortal address*/;
-
-	private static LitecoinACCTv2 instance;
-
-	private LitecoinACCTv2() {
-	}
-
-	public static synchronized LitecoinACCTv2 getInstance() {
-		if (instance == null)
-			instance = new LitecoinACCTv2();
-
-		return instance;
-	}
-
-	@Override
-	public byte[] getCodeBytesHash() {
-		return CODE_BYTES_HASH;
-	}
-
-	@Override
-	public int getModeByteOffset() {
-		return MODE_BYTE_OFFSET;
-	}
-
-	@Override
-	public ForeignBlockchain getBlockchain() {
-		return Litecoin.getInstance();
-	}
-
-	/**
-	 * Returns Qortal AT creation bytes for cross-chain trading AT.
-	 * <p>
-	 * <tt>tradeTimeout</tt> (minutes) is the time window for the trade partner to send the
-	 * 32-byte secret to the AT, before the AT automatically refunds the AT's creator.
-	 * 
-	 * @param creatorTradeAddress AT creator's trade Qortal address
-	 * @param litecoinPublicKeyHash 20-byte HASH160 of creator's trade Litecoin public key
-	 * @param qortAmount how much QORT to pay trade partner if they send correct 32-byte secrets to AT
-	 * @param litecoinAmount how much LTC the AT creator is expecting to trade
-	 * @param tradeTimeout suggested timeout for entire trade
-	 */
-	public static byte[] buildQortalAT(String creatorTradeAddress, byte[] litecoinPublicKeyHash, long qortAmount, long litecoinAmount, int tradeTimeout) {
-		if (litecoinPublicKeyHash.length != 20)
-			throw new IllegalArgumentException("Litecoin public key hash should be 20 bytes");
-
-		// Labels for data segment addresses
-		int addrCounter = 0;
-
-		// Constants (with corresponding dataByteBuffer.put*() calls below)
-
-		final int addrCreatorTradeAddress1 = addrCounter++;
-		final int addrCreatorTradeAddress2 = addrCounter++;
-		final int addrCreatorTradeAddress3 = addrCounter++;
-		final int addrCreatorTradeAddress4 = addrCounter++;
-
-		final int addrLitecoinPublicKeyHash = addrCounter;
-		addrCounter += 4;
-
-		final int addrQortAmount = addrCounter++;
-		final int addrLitecoinAmount = addrCounter++;
-		final int addrTradeTimeout = addrCounter++;
-
-		final int addrMessageTxnType = addrCounter++;
-		final int addrExpectedTradeMessageLength = addrCounter++;
-		final int addrExpectedRedeemMessageLength = addrCounter++;
-
-		final int addrCreatorAddressPointer = addrCounter++;
-		final int addrQortalPartnerAddressPointer = addrCounter++;
-		final int addrMessageSenderPointer = addrCounter++;
-
-		final int addrTradeMessagePartnerLitecoinPKHOffset = addrCounter++;
-		final int addrPartnerLitecoinPKHPointer = addrCounter++;
-		final int addrTradeMessageHashOfSecretAOffset = addrCounter++;
-		final int addrHashOfSecretAPointer = addrCounter++;
-
-		final int addrRedeemMessageReceivingAddressOffset = addrCounter++;
-
-		final int addrMessageDataPointer = addrCounter++;
-		final int addrMessageDataLength = addrCounter++;
-
-		final int addrPartnerReceivingAddressPointer = addrCounter++;
-
-		final int addrEndOfConstants = addrCounter;
-
-		// Variables
-
-		final int addrCreatorAddress1 = addrCounter++;
-		final int addrCreatorAddress2 = addrCounter++;
-		final int addrCreatorAddress3 = addrCounter++;
-		final int addrCreatorAddress4 = addrCounter++;
-
-		final int addrQortalPartnerAddress1 = addrCounter++;
-		final int addrQortalPartnerAddress2 = addrCounter++;
-		final int addrQortalPartnerAddress3 = addrCounter++;
-		final int addrQortalPartnerAddress4 = addrCounter++;
-
-		final int addrLockTimeA = addrCounter++;
-		final int addrRefundTimeout = addrCounter++;
-		final int addrRefundTimestamp = addrCounter++;
-		final int addrLastTxnTimestamp = addrCounter++;
-		final int addrBlockTimestamp = addrCounter++;
-		final int addrTxnType = addrCounter++;
-		final int addrResult = addrCounter++;
-
-		final int addrMessageSender1 = addrCounter++;
-		final int addrMessageSender2 = addrCounter++;
-		final int addrMessageSender3 = addrCounter++;
-		final int addrMessageSender4 = addrCounter++;
-
-		final int addrMessageLength = addrCounter++;
-
-		final int addrMessageData = addrCounter;
-		addrCounter += 4;
-
-		final int addrHashOfSecretA = addrCounter;
-		addrCounter += 4;
-
-		final int addrPartnerLitecoinPKH = addrCounter;
-		addrCounter += 4;
-
-		final int addrPartnerReceivingAddress = addrCounter;
-		addrCounter += 4;
-
-		final int addrMode = addrCounter++;
-		assert addrMode == MODE_VALUE_OFFSET : String.format("addrMode %d does not match MODE_VALUE_OFFSET %d", addrMode, MODE_VALUE_OFFSET);
-
-		// Data segment
-		ByteBuffer dataByteBuffer = ByteBuffer.allocate(addrCounter * MachineState.VALUE_SIZE);
-
-		// AT creator's trade Qortal address, decoded from Base58
-		assert dataByteBuffer.position() == addrCreatorTradeAddress1 * MachineState.VALUE_SIZE : "addrCreatorTradeAddress1 incorrect";
-		byte[] creatorTradeAddressBytes = Base58.decode(creatorTradeAddress);
-		dataByteBuffer.put(Bytes.ensureCapacity(creatorTradeAddressBytes, 32, 0));
-
-		// Litecoin public key hash
-		assert dataByteBuffer.position() == addrLitecoinPublicKeyHash * MachineState.VALUE_SIZE : "addrLitecoinPublicKeyHash incorrect";
-		dataByteBuffer.put(Bytes.ensureCapacity(litecoinPublicKeyHash, 32, 0));
-
-		// Redeem Qort amount
-		assert dataByteBuffer.position() == addrQortAmount * MachineState.VALUE_SIZE : "addrQortAmount incorrect";
-		dataByteBuffer.putLong(qortAmount);
-
-		// Expected Litecoin amount
-		assert dataByteBuffer.position() == addrLitecoinAmount * MachineState.VALUE_SIZE : "addrLitecoinAmount incorrect";
-		dataByteBuffer.putLong(litecoinAmount);
-
-		// Suggested trade timeout (minutes)
-		assert dataByteBuffer.position() == addrTradeTimeout * MachineState.VALUE_SIZE : "addrTradeTimeout incorrect";
-		dataByteBuffer.putLong(tradeTimeout);
-
-		// We're only interested in MESSAGE transactions
-		assert dataByteBuffer.position() == addrMessageTxnType * MachineState.VALUE_SIZE : "addrMessageTxnType incorrect";
-		dataByteBuffer.putLong(API.ATTransactionType.MESSAGE.value);
-
-		// Expected length of 'trade' MESSAGE data from AT creator
-		assert dataByteBuffer.position() == addrExpectedTradeMessageLength * MachineState.VALUE_SIZE : "addrExpectedTradeMessageLength incorrect";
-		dataByteBuffer.putLong(TRADE_MESSAGE_LENGTH);
-
-		// Expected length of 'redeem' MESSAGE data from trade partner
-		assert dataByteBuffer.position() == addrExpectedRedeemMessageLength * MachineState.VALUE_SIZE : "addrExpectedRedeemMessageLength incorrect";
-		dataByteBuffer.putLong(REDEEM_MESSAGE_LENGTH);
-
-		// Index into data segment of AT creator's address, used by GET_B_IND
-		assert dataByteBuffer.position() == addrCreatorAddressPointer * MachineState.VALUE_SIZE : "addrCreatorAddressPointer incorrect";
-		dataByteBuffer.putLong(addrCreatorAddress1);
-
-		// Index into data segment of partner's Qortal address, used by SET_B_IND
-		assert dataByteBuffer.position() == addrQortalPartnerAddressPointer * MachineState.VALUE_SIZE : "addrQortalPartnerAddressPointer incorrect";
-		dataByteBuffer.putLong(addrQortalPartnerAddress1);
-
-		// Index into data segment of (temporary) transaction's sender's address, used by GET_B_IND
-		assert dataByteBuffer.position() == addrMessageSenderPointer * MachineState.VALUE_SIZE : "addrMessageSenderPointer incorrect";
-		dataByteBuffer.putLong(addrMessageSender1);
-
-		// Offset into 'trade' MESSAGE data payload for extracting partner's Litecoin PKH
-		assert dataByteBuffer.position() == addrTradeMessagePartnerLitecoinPKHOffset * MachineState.VALUE_SIZE : "addrTradeMessagePartnerLitecoinPKHOffset incorrect";
-		dataByteBuffer.putLong(32L);
-
-		// Index into data segment of partner's Litecoin PKH, used by GET_B_IND
-		assert dataByteBuffer.position() == addrPartnerLitecoinPKHPointer * MachineState.VALUE_SIZE : "addrPartnerLitecoinPKHPointer incorrect";
-		dataByteBuffer.putLong(addrPartnerLitecoinPKH);
-
-		// Offset into 'trade' MESSAGE data payload for extracting hash-of-secret-A
-		assert dataByteBuffer.position() == addrTradeMessageHashOfSecretAOffset * MachineState.VALUE_SIZE : "addrTradeMessageHashOfSecretAOffset incorrect";
-		dataByteBuffer.putLong(64L);
-
-		// Index into data segment to hash of secret A, used by GET_B_IND
-		assert dataByteBuffer.position() == addrHashOfSecretAPointer * MachineState.VALUE_SIZE : "addrHashOfSecretAPointer incorrect";
-		dataByteBuffer.putLong(addrHashOfSecretA);
-
-		// Offset into 'redeem' MESSAGE data payload for extracting Qortal receiving address
-		assert dataByteBuffer.position() == addrRedeemMessageReceivingAddressOffset * MachineState.VALUE_SIZE : "addrRedeemMessageReceivingAddressOffset incorrect";
-		dataByteBuffer.putLong(32L);
-
-		// Source location and length for hashing any passed secret
-		assert dataByteBuffer.position() == addrMessageDataPointer * MachineState.VALUE_SIZE : "addrMessageDataPointer incorrect";
-		dataByteBuffer.putLong(addrMessageData);
-		assert dataByteBuffer.position() == addrMessageDataLength * MachineState.VALUE_SIZE : "addrMessageDataLength incorrect";
-		dataByteBuffer.putLong(32L);
-
-		// Pointer into data segment of where to save partner's receiving Qortal address, used by GET_B_IND
-		assert dataByteBuffer.position() == addrPartnerReceivingAddressPointer * MachineState.VALUE_SIZE : "addrPartnerReceivingAddressPointer incorrect";
-		dataByteBuffer.putLong(addrPartnerReceivingAddress);
-
-		assert dataByteBuffer.position() == addrEndOfConstants * MachineState.VALUE_SIZE : "dataByteBuffer position not at end of constants";
-
-		// Code labels
-		Integer labelRefund = null;
-
-		Integer labelTradeTxnLoop = null;
-		Integer labelCheckTradeTxn = null;
-		Integer labelCheckCancelTxn = null;
-		Integer labelNotTradeNorCancelTxn = null;
-		Integer labelCheckNonRefundTradeTxn = null;
-		Integer labelTradeTxnExtract = null;
-		Integer labelRedeemTxnLoop = null;
-		Integer labelCheckRedeemTxn = null;
-		Integer labelCheckRedeemTxnSender = null;
-		Integer labelPayout = null;
-
-		ByteBuffer codeByteBuffer = ByteBuffer.allocate(768);
-
-		// Two-pass version
-		for (int pass = 0; pass < 2; ++pass) {
-			codeByteBuffer.clear();
-
-			try {
-				/* Initialization */
-
-				// Use AT creation 'timestamp' as starting point for finding transactions sent to AT
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_CREATION_TIMESTAMP, addrLastTxnTimestamp));
-
-				// Load B register with AT creator's address so we can save it into addrCreatorAddress1-4
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_CREATOR_INTO_B));
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrCreatorAddressPointer));
-
-				// Set restart position to after this opcode
-				codeByteBuffer.put(OpCode.SET_PCS.compile());
-
-				/* Loop, waiting for message from AT creator's trade address containing trade partner details, or AT owner's address to cancel offer */
-
-				/* Transaction processing loop */
-				labelTradeTxnLoop = codeByteBuffer.position();
-
-				/* Sleep until message arrives */
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.SLEEP_UNTIL_MESSAGE.value, addrLastTxnTimestamp));
-
-				// Find next transaction (if any) to this AT since the last one (referenced by addrLastTxnTimestamp)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PUT_TX_AFTER_TIMESTAMP_INTO_A, addrLastTxnTimestamp));
-				// If no transaction found, A will be zero. If A is zero, set addrResult to 1, otherwise 0.
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.CHECK_A_IS_ZERO, addrResult));
-				// If addrResult is zero (i.e. A is non-zero, transaction was found) then go check transaction
-				codeByteBuffer.put(OpCode.BZR_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelCheckTradeTxn)));
-				// Stop and wait for next block
-				codeByteBuffer.put(OpCode.STP_IMD.compile());
-
-				/* Check transaction */
-				labelCheckTradeTxn = codeByteBuffer.position();
-
-				// Update our 'last found transaction's timestamp' using 'timestamp' from transaction
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TIMESTAMP_FROM_TX_IN_A, addrLastTxnTimestamp));
-				// Extract transaction type (message/payment) from transaction and save type in addrTxnType
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TYPE_FROM_TX_IN_A, addrTxnType));
-				// If transaction type is not MESSAGE type then go look for another transaction
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrTxnType, addrMessageTxnType, calcOffset(codeByteBuffer, labelTradeTxnLoop)));
-
-				/* Check transaction's sender. We're expecting AT creator's trade address for 'trade' message, or AT creator's own address for 'cancel' message. */
-
-				// Extract sender address from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_ADDRESS_FROM_TX_IN_A_INTO_B));
-				// Save B register into data segment starting at addrMessageSender1 (as pointed to by addrMessageSenderPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageSenderPointer));
-				// Compare each part of message sender's address with AT creator's trade address. If they don't match, check for cancel situation.
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrCreatorTradeAddress1, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrCreatorTradeAddress2, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrCreatorTradeAddress3, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrCreatorTradeAddress4, calcOffset(codeByteBuffer, labelCheckCancelTxn)));
-				// Message sender's address matches AT creator's trade address so go process 'trade' message
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelCheckNonRefundTradeTxn == null ? 0 : labelCheckNonRefundTradeTxn));
-
-				/* Checking message sender for possible cancel message */
-				labelCheckCancelTxn = codeByteBuffer.position();
-
-				// Compare each part of message sender's address with AT creator's address. If they don't match, look for another transaction.
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrCreatorAddress1, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrCreatorAddress2, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrCreatorAddress3, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrCreatorAddress4, calcOffset(codeByteBuffer, labelNotTradeNorCancelTxn)));
-				// Partner address is AT creator's address, so cancel offer and finish.
-				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.CANCELLED.value));
-				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
-				codeByteBuffer.put(OpCode.FIN_IMD.compile());
-
-				/* Not trade nor cancel message */
-				labelNotTradeNorCancelTxn = codeByteBuffer.position();
-
-				// Loop to find another transaction
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelTradeTxnLoop == null ? 0 : labelTradeTxnLoop));
-
-				/* Possible switch-to-trade-mode message */
-				labelCheckNonRefundTradeTxn = codeByteBuffer.position();
-
-				// Check 'trade' message we received has expected number of message bytes
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(QortalFunctionCode.GET_MESSAGE_LENGTH_FROM_TX_IN_A.value, addrMessageLength));
-				// If message length matches, branch to info extraction code
-				codeByteBuffer.put(OpCode.BEQ_DAT.compile(addrMessageLength, addrExpectedTradeMessageLength, calcOffset(codeByteBuffer, labelTradeTxnExtract)));
-				// Message length didn't match - go back to finding another 'trade' MESSAGE transaction
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelTradeTxnLoop == null ? 0 : labelTradeTxnLoop));
-
-				/* Extracting info from 'trade' MESSAGE transaction */
-				labelTradeTxnExtract = codeByteBuffer.position();
-
-				// Extract message from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_MESSAGE_FROM_TX_IN_A_INTO_B));
-				// Save B register into data segment starting at addrQortalPartnerAddress1 (as pointed to by addrQortalPartnerAddressPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrQortalPartnerAddressPointer));
-
-				// Extract trade partner's Litecoin public key hash (PKH) from message into B
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessagePartnerLitecoinPKHOffset));
-				// Store partner's Litecoin PKH (we only really use values from B1-B3)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerLitecoinPKHPointer));
-				// Extract AT trade timeout (minutes) (from B4)
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_B4, addrRefundTimeout));
-
-				// Grab next 32 bytes
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrTradeMessageHashOfSecretAOffset));
-
-				// Extract hash-of-secret-A (we only really use values from B1-B3)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrHashOfSecretAPointer));
-				// Extract lockTime-A (from B4)
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_B4, addrLockTimeA));
-
-				// Calculate trade timeout refund 'timestamp' by adding addrRefundTimeout minutes to this transaction's 'timestamp', then save into addrRefundTimestamp
-				codeByteBuffer.put(OpCode.EXT_FUN_RET_DAT_2.compile(FunctionCode.ADD_MINUTES_TO_TIMESTAMP, addrRefundTimestamp, addrLastTxnTimestamp, addrRefundTimeout));
-
-				/* We are in 'trade mode' */
-				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.TRADING.value));
-
-				// Set restart position to after this opcode
-				codeByteBuffer.put(OpCode.SET_PCS.compile());
-
-				/* Loop, waiting for trade timeout or 'redeem' MESSAGE from Qortal trade partner */
-
-				// Fetch current block 'timestamp'
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_BLOCK_TIMESTAMP, addrBlockTimestamp));
-				// If we're not past refund 'timestamp' then look for next transaction
-				codeByteBuffer.put(OpCode.BLT_DAT.compile(addrBlockTimestamp, addrRefundTimestamp, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-				// We're past refund 'timestamp' so go refund everything back to AT creator
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRefund == null ? 0 : labelRefund));
-
-				/* Transaction processing loop */
-				labelRedeemTxnLoop = codeByteBuffer.position();
-
-				/* Sleep until message arrives */
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.SLEEP_UNTIL_MESSAGE.value, addrLastTxnTimestamp));
-
-				// Find next transaction to this AT since the last one (if any)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PUT_TX_AFTER_TIMESTAMP_INTO_A, addrLastTxnTimestamp));
-				// If no transaction found, A will be zero. If A is zero, set addrComparator to 1, otherwise 0.
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.CHECK_A_IS_ZERO, addrResult));
-				// If addrResult is zero (i.e. A is non-zero, transaction was found) then go check transaction
-				codeByteBuffer.put(OpCode.BZR_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelCheckRedeemTxn)));
-				// Stop and wait for next block
-				codeByteBuffer.put(OpCode.STP_IMD.compile());
-
-				/* Check transaction */
-				labelCheckRedeemTxn = codeByteBuffer.position();
-
-				// Update our 'last found transaction's timestamp' using 'timestamp' from transaction
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TIMESTAMP_FROM_TX_IN_A, addrLastTxnTimestamp));
-				// Extract transaction type (message/payment) from transaction and save type in addrTxnType
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(FunctionCode.GET_TYPE_FROM_TX_IN_A, addrTxnType));
-				// If transaction type is not MESSAGE type then go look for another transaction
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrTxnType, addrMessageTxnType, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-
-				/* Check message payload length */
-				codeByteBuffer.put(OpCode.EXT_FUN_RET.compile(QortalFunctionCode.GET_MESSAGE_LENGTH_FROM_TX_IN_A.value, addrMessageLength));
-				// If message length matches, branch to sender checking code
-				codeByteBuffer.put(OpCode.BEQ_DAT.compile(addrMessageLength, addrExpectedRedeemMessageLength, calcOffset(codeByteBuffer, labelCheckRedeemTxnSender)));
-				// Message length didn't match - go back to finding another 'redeem' MESSAGE transaction
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRedeemTxnLoop == null ? 0 : labelRedeemTxnLoop));
-
-				/* Check transaction's sender */
-				labelCheckRedeemTxnSender = codeByteBuffer.position();
-
-				// Extract sender address from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_ADDRESS_FROM_TX_IN_A_INTO_B));
-				// Save B register into data segment starting at addrMessageSender1 (as pointed to by addrMessageSenderPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageSenderPointer));
-				// Compare each part of transaction's sender's address with expected address. If they don't match, look for another transaction.
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender1, addrQortalPartnerAddress1, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender2, addrQortalPartnerAddress2, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender3, addrQortalPartnerAddress3, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-				codeByteBuffer.put(OpCode.BNE_DAT.compile(addrMessageSender4, addrQortalPartnerAddress4, calcOffset(codeByteBuffer, labelRedeemTxnLoop)));
-
-				/* Check 'secret-A' in transaction's message */
-
-				// Extract secret-A from first 32 bytes of message from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN.compile(FunctionCode.PUT_MESSAGE_FROM_TX_IN_A_INTO_B));
-				// Save B register into data segment starting at addrMessageData (as pointed to by addrMessageDataPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrMessageDataPointer));
-				// Load B register with expected hash result (as pointed to by addrHashOfSecretAPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.SET_B_IND, addrHashOfSecretAPointer));
-				// Perform HASH160 using source data at addrMessageData. (Location and length specified via addrMessageDataPointer and addrMessageDataLength).
-				// Save the equality result (1 if they match, 0 otherwise) into addrResult.
-				codeByteBuffer.put(OpCode.EXT_FUN_RET_DAT_2.compile(FunctionCode.CHECK_HASH160_WITH_B, addrResult, addrMessageDataPointer, addrMessageDataLength));
-				// If hashes don't match, addrResult will be zero so go find another transaction
-				codeByteBuffer.put(OpCode.BNZ_DAT.compile(addrResult, calcOffset(codeByteBuffer, labelPayout)));
-				codeByteBuffer.put(OpCode.JMP_ADR.compile(labelRedeemTxnLoop == null ? 0 : labelRedeemTxnLoop));
-
-				/* Success! Pay arranged amount to receiving address */
-				labelPayout = codeByteBuffer.position();
-
-				// Extract Qortal receiving address from next 32 bytes of message from transaction into B register
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(QortalFunctionCode.PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.value, addrRedeemMessageReceivingAddressOffset));
-				// Save B register into data segment starting at addrPartnerReceivingAddress (as pointed to by addrPartnerReceivingAddressPointer)
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.GET_B_IND, addrPartnerReceivingAddressPointer));
-				// Pay AT's balance to receiving address
-				codeByteBuffer.put(OpCode.EXT_FUN_DAT.compile(FunctionCode.PAY_TO_ADDRESS_IN_B, addrQortAmount));
-				// Set redeemed mode
-				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.REDEEMED.value));
-				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
-				codeByteBuffer.put(OpCode.FIN_IMD.compile());
-
-				// Fall-through to refunding any remaining balance back to AT creator
-
-				/* Refund balance back to AT creator */
-				labelRefund = codeByteBuffer.position();
-
-				// Set refunded mode
-				codeByteBuffer.put(OpCode.SET_VAL.compile(addrMode, AcctMode.REFUNDED.value));
-				// We're finished forever (finishing auto-refunds remaining balance to AT creator)
-				codeByteBuffer.put(OpCode.FIN_IMD.compile());
-			} catch (CompilationException e) {
-				throw new IllegalStateException("Unable to compile LTC-QORT ACCT?", e);
-			}
-		}
-
-		codeByteBuffer.flip();
-
-		byte[] codeBytes = new byte[codeByteBuffer.limit()];
-		codeByteBuffer.get(codeBytes);
-
-		assert Arrays.equals(Crypto.digest(codeBytes), LitecoinACCTv2.CODE_BYTES_HASH)
-			: String.format("BTCACCT.CODE_BYTES_HASH mismatch: expected %s, actual %s", HashCode.fromBytes(CODE_BYTES_HASH), HashCode.fromBytes(Crypto.digest(codeBytes)));
-
-		final short ciyamAtVersion = 2;
-		final short numCallStackPages = 0;
-		final short numUserStackPages = 0;
-		final long minActivationAmount = 0L;
-
-		return MachineState.toCreationBytes(ciyamAtVersion, codeBytes, dataByteBuffer.array(), numCallStackPages, numUserStackPages, minActivationAmount);
-	}
-
-	/**
-	 * Returns CrossChainTradeData with useful info extracted from AT.
-	 */
-	@Override
-	public CrossChainTradeData populateTradeData(Repository repository, ATData atData) throws DataException {
-		ATStateData atStateData = repository.getATRepository().getLatestATState(atData.getATAddress());
-		return populateTradeData(repository, atData.getCreatorPublicKey(), atData.getCreation(), atStateData);
-	}
-
-	/**
-	 * Returns CrossChainTradeData with useful info extracted from AT.
-	 */
-	@Override
-	public CrossChainTradeData populateTradeData(Repository repository, ATStateData atStateData) throws DataException {
-		ATData atData = repository.getATRepository().fromATAddress(atStateData.getATAddress());
-		return populateTradeData(repository, atData.getCreatorPublicKey(), atData.getCreation(), atStateData);
-	}
-
-	/**
-	 * Returns CrossChainTradeData with useful info extracted from AT.
-	 */
-	public CrossChainTradeData populateTradeData(Repository repository, byte[] creatorPublicKey, long creationTimestamp, ATStateData atStateData) throws DataException {
-		byte[] addressBytes = new byte[25]; // for general use
-		String atAddress = atStateData.getATAddress();
-
-		CrossChainTradeData tradeData = new CrossChainTradeData();
-
-		tradeData.foreignBlockchain = SupportedBlockchain.LITECOIN.name();
-		tradeData.acctName = NAME;
-
-		tradeData.qortalAtAddress = atAddress;
-		tradeData.qortalCreator = Crypto.toAddress(creatorPublicKey);
-		tradeData.creationTimestamp = creationTimestamp;
-
-		Account atAccount = new Account(repository, atAddress);
-		tradeData.qortBalance = atAccount.getConfirmedBalance(Asset.QORT);
-
-		byte[] stateData = atStateData.getStateData();
-		ByteBuffer dataByteBuffer = ByteBuffer.wrap(stateData);
-		dataByteBuffer.position(MachineState.HEADER_LENGTH);
-
-		/* Constants */
-
-		// Skip creator's trade address
-		dataByteBuffer.get(addressBytes);
-		tradeData.qortalCreatorTradeAddress = Base58.encode(addressBytes);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - addressBytes.length);
-
-		// Creator's Litecoin/foreign public key hash
-		tradeData.creatorForeignPKH = new byte[20];
-		dataByteBuffer.get(tradeData.creatorForeignPKH);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - tradeData.creatorForeignPKH.length); // skip to 32 bytes
-
-		// We don't use secret-B
-		tradeData.hashOfSecretB = null;
-
-		// Redeem payout
-		tradeData.qortAmount = dataByteBuffer.getLong();
-
-		// Expected LTC amount
-		tradeData.expectedForeignAmount = dataByteBuffer.getLong();
-
-		// Trade timeout
-		tradeData.tradeTimeout = (int) dataByteBuffer.getLong();
-
-		// Skip MESSAGE transaction type
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip expected 'trade' message length
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip expected 'redeem' message length
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to creator's address
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to partner's Qortal trade address
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to message sender
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip 'trade' message data offset for partner's Litecoin PKH
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to partner's Litecoin PKH
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip 'trade' message data offset for hash-of-secret-A
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to hash-of-secret-A
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip 'redeem' message data offset for partner's Qortal receiving address
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to message data
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip message data length
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip pointer to partner's receiving address
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		/* End of constants / begin variables */
-
-		// Skip AT creator's address
-		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
-
-		// Partner's trade address (if present)
-		dataByteBuffer.get(addressBytes);
-		String qortalRecipient = Base58.encode(addressBytes);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - addressBytes.length);
-
-		// Potential lockTimeA (if in trade mode)
-		int lockTimeA = (int) dataByteBuffer.getLong();
-
-		// AT refund timeout (probably only useful for debugging)
-		int refundTimeout = (int) dataByteBuffer.getLong();
-
-		// Trade-mode refund timestamp (AT 'timestamp' converted to Qortal block height)
-		long tradeRefundTimestamp = dataByteBuffer.getLong();
-
-		// Skip last transaction timestamp
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip block timestamp
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip transaction type
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip temporary result
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip temporary message sender
-		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
-
-		// Skip message length
-		dataByteBuffer.position(dataByteBuffer.position() + 8);
-
-		// Skip temporary message data
-		dataByteBuffer.position(dataByteBuffer.position() + 8 * 4);
-
-		// Potential hash160 of secret A
-		byte[] hashOfSecretA = new byte[20];
-		dataByteBuffer.get(hashOfSecretA);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - hashOfSecretA.length); // skip to 32 bytes
-
-		// Potential partner's Litecoin PKH
-		byte[] partnerLitecoinPKH = new byte[20];
-		dataByteBuffer.get(partnerLitecoinPKH);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerLitecoinPKH.length); // skip to 32 bytes
-
-		// Partner's receiving address (if present)
-		byte[] partnerReceivingAddress = new byte[25];
-		dataByteBuffer.get(partnerReceivingAddress);
-		dataByteBuffer.position(dataByteBuffer.position() + 32 - partnerReceivingAddress.length); // skip to 32 bytes
-
-		// Trade AT's 'mode'
-		long modeValue = dataByteBuffer.getLong();
-		AcctMode mode = AcctMode.valueOf((int) (modeValue & 0xffL));
-
-		/* End of variables */
-
-		if (mode != null && mode != AcctMode.OFFERING) {
-			tradeData.mode = mode;
-			tradeData.refundTimeout = refundTimeout;
-			tradeData.tradeRefundHeight = new Timestamp(tradeRefundTimestamp).blockHeight;
-			tradeData.qortalPartnerAddress = qortalRecipient;
-			tradeData.hashOfSecretA = hashOfSecretA;
-			tradeData.partnerForeignPKH = partnerLitecoinPKH;
-			tradeData.lockTimeA = lockTimeA;
-
-			if (mode == AcctMode.REDEEMED)
-				tradeData.qortalPartnerReceivingAddress = Base58.encode(partnerReceivingAddress);
-		} else {
-			tradeData.mode = AcctMode.OFFERING;
-		}
-
-		tradeData.duplicateDeprecated();
-
-		return tradeData;
-	}
-
-	/** Returns 'offer' MESSAGE payload for trade partner to send to AT creator's trade address. */
-	public static byte[] buildOfferMessage(byte[] partnerBitcoinPKH, byte[] hashOfSecretA, int lockTimeA) {
-		byte[] lockTimeABytes = BitTwiddling.toBEByteArray((long) lockTimeA);
-		return Bytes.concat(partnerBitcoinPKH, hashOfSecretA, lockTimeABytes);
-	}
-
-	/** Returns info extracted from 'offer' MESSAGE payload sent by trade partner to AT creator's trade address, or null if not valid. */
-	public static OfferMessageData extractOfferMessageData(byte[] messageData) {
-		if (messageData == null || messageData.length != OFFER_MESSAGE_LENGTH)
-			return null;
-
-		OfferMessageData offerMessageData = new OfferMessageData();
-		offerMessageData.partnerLitecoinPKH = Arrays.copyOfRange(messageData, 0, 20);
-		offerMessageData.hashOfSecretA = Arrays.copyOfRange(messageData, 20, 40);
-		offerMessageData.lockTimeA = BitTwiddling.longFromBEBytes(messageData, 40);
-
-		return offerMessageData;
-	}
-
-	/** Returns 'trade' MESSAGE payload for AT creator to send to AT. */
-	public static byte[] buildTradeMessage(String partnerQortalTradeAddress, byte[] partnerBitcoinPKH, byte[] hashOfSecretA, int lockTimeA, int refundTimeout) {
-		byte[] data = new byte[TRADE_MESSAGE_LENGTH];
-		byte[] partnerQortalAddressBytes = Base58.decode(partnerQortalTradeAddress);
-		byte[] lockTimeABytes = BitTwiddling.toBEByteArray((long) lockTimeA);
-		byte[] refundTimeoutBytes = BitTwiddling.toBEByteArray((long) refundTimeout);
-
-		System.arraycopy(partnerQortalAddressBytes, 0, data, 0, partnerQortalAddressBytes.length);
-		System.arraycopy(partnerBitcoinPKH, 0, data, 32, partnerBitcoinPKH.length);
-		System.arraycopy(refundTimeoutBytes, 0, data, 56, refundTimeoutBytes.length);
-		System.arraycopy(hashOfSecretA, 0, data, 64, hashOfSecretA.length);
-		System.arraycopy(lockTimeABytes, 0, data, 88, lockTimeABytes.length);
-
-		return data;
-	}
-
-	/** Returns 'cancel' MESSAGE payload for AT creator to cancel trade AT. */
-	@Override
-	public byte[] buildCancelMessage(String creatorQortalAddress) {
-		byte[] data = new byte[CANCEL_MESSAGE_LENGTH];
-		byte[] creatorQortalAddressBytes = Base58.decode(creatorQortalAddress);
-
-		System.arraycopy(creatorQortalAddressBytes, 0, data, 0, creatorQortalAddressBytes.length);
-
-		return data;
-	}
-
-	/** Returns 'redeem' MESSAGE payload for trade partner to send to AT. */
-	public static byte[] buildRedeemMessage(byte[] secretA, String qortalReceivingAddress) {
-		byte[] data = new byte[REDEEM_MESSAGE_LENGTH];
-		byte[] qortalReceivingAddressBytes = Base58.decode(qortalReceivingAddress);
-
-		System.arraycopy(secretA, 0, data, 0, secretA.length);
-		System.arraycopy(qortalReceivingAddressBytes, 0, data, 32, qortalReceivingAddressBytes.length);
-
-		return data;
-	}
-
-	/** Returns refund timeout (minutes) based on trade partner's 'offer' MESSAGE timestamp and P2SH-A locktime. */
-	public static int calcRefundTimeout(long offerMessageTimestamp, int lockTimeA) {
-		// refund should be triggered halfway between offerMessageTimestamp and lockTimeA
-		return (int) ((lockTimeA - (offerMessageTimestamp / 1000L)) / 2L / 60L);
-	}
-
-	@Override
-	public byte[] findSecretA(Repository repository, CrossChainTradeData crossChainTradeData) throws DataException {
-		String atAddress = crossChainTradeData.qortalAtAddress;
-		String redeemerAddress = crossChainTradeData.qortalPartnerAddress;
-
-		// We don't have partner's public key so we check every message to AT
-		List<MessageTransactionData> messageTransactionsData = repository.getMessageRepository().getMessagesByParticipants(null, atAddress, null, null, null);
-		if (messageTransactionsData == null)
-			return null;
-
-		// Find 'redeem' message
-		for (MessageTransactionData messageTransactionData : messageTransactionsData) {
-			// Check message payload type/encryption
-			if (messageTransactionData.isText() || messageTransactionData.isEncrypted())
-				continue;
-
-			// Check message payload size
-			byte[] messageData = messageTransactionData.getData();
-			if (messageData.length != REDEEM_MESSAGE_LENGTH)
-				// Wrong payload length
-				continue;
-
-			// Check sender
-			if (!Crypto.toAddress(messageTransactionData.getSenderPublicKey()).equals(redeemerAddress))
-				// Wrong sender;
-				continue;
-
-			// Extract secretA
-			byte[] secretA = new byte[32];
-			System.arraycopy(messageData, 0, secretA, 0, secretA.length);
-
-			byte[] hashOfSecretA = Crypto.hash160(secretA);
-			if (!Arrays.equals(hashOfSecretA, crossChainTradeData.hashOfSecretA))
-				continue;
-
-			return secretA;
-		}
-
-		return null;
-	}
-
-}

src/main/java/org/qortal/crosschain/PirateChain.java

@@ -4,6 +4,12 @@ import cash.z.wallet.sdk.rpc.CompactFormats;
 import com.google.common.hash.HashCode;
 import com.rust.litewalletjni.LiteWalletJni;
 import org.bitcoinj.core.*;
+import org.bitcoinj.crypto.ChildNumber;
+import org.bitcoinj.crypto.DeterministicKey;
+import org.bitcoinj.script.Script;
+import org.bitcoinj.script.ScriptBuilder;
+import org.bitcoinj.wallet.DeterministicKeyChain;
+import org.bitcoinj.wallet.Wallet;
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -352,6 +358,12 @@ public class PirateChain extends Bitcoiny {
 		}
 	}
 
+	public String getUnusedReceiveAddress(String key58) throws ForeignBlockchainException {
+		// For now, return the main wallet address
+		// FUTURE: generate an unused one
+		return this.getWalletAddress(key58);
+	}
+
 	public String sendCoins(PirateChainSendRequest pirateChainSendRequest) throws ForeignBlockchainException {
 		PirateChainWalletController walletController = PirateChainWalletController.getInstance();
 		walletController.initWithEntropy58(pirateChainSendRequest.entropy58);

src/main/java/org/qortal/crosschain/PirateChainHTLC.java

@@ -3,25 +3,17 @@ package org.qortal.crosschain;
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Bytes;
 import org.bitcoinj.core.*;
-import org.bitcoinj.core.Transaction.SigHash;
-import org.bitcoinj.crypto.TransactionSignature;
 import org.bitcoinj.script.Script;
-import org.bitcoinj.script.ScriptBuilder;
 import org.bitcoinj.script.ScriptChunk;
-import org.bitcoinj.script.ScriptOpCodes;
 import org.qortal.crypto.Crypto;
 import org.qortal.utils.Base58;
 import org.qortal.utils.BitTwiddling;
 
 import java.util.*;
-import java.util.function.Function;
+import static org.qortal.crosschain.BitcoinyHTLC.Status;
 
 public class PirateChainHTLC {
 
-	public enum Status {
-		UNFUNDED, FUNDING_IN_PROGRESS, FUNDED, REDEEM_IN_PROGRESS, REDEEMED, REFUND_IN_PROGRESS, REFUNDED
-	}
-
 	public static final int SECRET_LENGTH = 32;
 	public static final int MIN_LOCKTIME = 1500000000;
 

src/main/java/org/qortal/crosschain/PirateWallet.java

@@ -117,7 +117,7 @@ public class PirateWallet {
                 // Restore existing wallet
                 String response = LiteWalletJni.initfromb64(serverUri, params, wallet, saplingOutput64, saplingSpend64);
                 if (response != null && !response.contains("\"initalized\":true")) {
-                    LOGGER.info("Unable to initialize Pirate Chain wallet: {}", response);
+                    LOGGER.info("Unable to initialize Pirate Chain wallet at {}: {}", serverUri, response);
                     return false;
                 }
                 this.seedPhrase = inputSeedPhrase;

src/main/java/org/qortal/crosschain/Ravencoin.java

@@ -138,6 +138,8 @@ public class Ravencoin extends Bitcoiny {
 			Context bitcoinjContext = new Context(ravencoinNet.getParams());
 
 			instance = new Ravencoin(ravencoinNet, electrumX, bitcoinjContext, CURRENCY_CODE);
+
+			electrumX.setBlockchain(instance);
 		}
 
 		return instance;

src/main/java/org/qortal/crosschain/SupportedBlockchain.java

@@ -29,7 +29,6 @@ public enum SupportedBlockchain {
 
 	LITECOIN(Arrays.asList(
 			Triple.valueOf(LitecoinACCTv1.NAME, LitecoinACCTv1.CODE_BYTES_HASH, LitecoinACCTv1::getInstance),
-			Triple.valueOf(LitecoinACCTv2.NAME, LitecoinACCTv2.CODE_BYTES_HASH, LitecoinACCTv2::getInstance),
 			Triple.valueOf(LitecoinACCTv3.NAME, LitecoinACCTv3.CODE_BYTES_HASH, LitecoinACCTv3::getInstance)
 		)) {
 		@Override
@@ -45,7 +44,6 @@ public enum SupportedBlockchain {
 
 	DOGECOIN(Arrays.asList(
 			Triple.valueOf(DogecoinACCTv1.NAME, DogecoinACCTv1.CODE_BYTES_HASH, DogecoinACCTv1::getInstance),
-			Triple.valueOf(DogecoinACCTv2.NAME, DogecoinACCTv2.CODE_BYTES_HASH, DogecoinACCTv2::getInstance),
 			Triple.valueOf(DogecoinACCTv3.NAME, DogecoinACCTv3.CODE_BYTES_HASH, DogecoinACCTv3::getInstance)
 		)) {
 		@Override

src/main/java/org/qortal/crypto/MemoryPoW.java

@@ -1,10 +1,44 @@
 package org.qortal.crypto;
 
+import org.qortal.utils.NTP;
+
 import java.nio.ByteBuffer;
+import java.util.concurrent.TimeoutException;
 
 public class MemoryPoW {
 
+	/**
+	 * Compute a MemoryPoW nonce
+	 *
+	 * @param data
+	 * @param workBufferLength
+	 * @param difficulty
+	 * @return
+	 * @throws TimeoutException
+	 */
 	public static Integer compute2(byte[] data, int workBufferLength, long difficulty) {
+		try {
+			return MemoryPoW.compute2(data, workBufferLength, difficulty, null);
+
+		} catch (TimeoutException e) {
+			// This won't happen, because above timeout is null
+			return null;
+		}
+	}
+
+	/**
+	 * Compute a MemoryPoW nonce, with optional timeout
+	 *
+	 * @param data
+	 * @param workBufferLength
+	 * @param difficulty
+	 * @param timeout maximum number of milliseconds to compute for before giving up,<br>or null if no timeout
+	 * @return
+	 * @throws TimeoutException
+	 */
+	public static Integer compute2(byte[] data, int workBufferLength, long difficulty, Long timeout) throws TimeoutException {
+		long startTime = NTP.getTime();
+
 		// Hash data with SHA256
 		byte[] hash = Crypto.digest(data);
 
@@ -33,6 +67,13 @@ public class MemoryPoW {
 			if (Thread.currentThread().isInterrupted())
 				return -1;
 
+			if (timeout != null) {
+				long now = NTP.getTime();
+				if (now > startTime + timeout) {
+					throw new TimeoutException("Timeout reached");
+				}
+			}
+
 			seed *= seedMultiplier; // per nonce
 
 			state[0] = longHash[0] ^ seed;
@@ -58,6 +99,10 @@ public class MemoryPoW {
 	}
 
 	public static boolean verify2(byte[] data, int workBufferLength, long difficulty, int nonce) {
+		return verify2(data, null, workBufferLength, difficulty, nonce);
+	}
+
+	public static boolean verify2(byte[] data, long[] workBuffer, int workBufferLength, long difficulty, int nonce) {
 		// Hash data with SHA256
 		byte[] hash = Crypto.digest(data);
 
@@ -70,7 +115,10 @@ public class MemoryPoW {
 		byteBuffer = null;
 
 		int longBufferLength = workBufferLength / 8;
-		long[] workBuffer = new long[longBufferLength];
+
+		if (workBuffer == null)
+			workBuffer = new long[longBufferLength];
+
 		long[] state = new long[4];
 
 		long seed = 8682522807148012L;

src/main/java/org/qortal/data/account/AccountData.java

@@ -18,6 +18,7 @@ public class AccountData {
 	protected int level;
 	protected int blocksMinted;
 	protected int blocksMintedAdjustment;
+	protected int blocksMintedPenalty;
 
 	// Constructors
 
@@ -25,7 +26,7 @@ public class AccountData {
 	protected AccountData() {
 	}
 
-	public AccountData(String address, byte[] reference, byte[] publicKey, int defaultGroupId, int flags, int level, int blocksMinted, int blocksMintedAdjustment) {
+	public AccountData(String address, byte[] reference, byte[] publicKey, int defaultGroupId, int flags, int level, int blocksMinted, int blocksMintedAdjustment, int blocksMintedPenalty) {
 		this.address = address;
 		this.reference = reference;
 		this.publicKey = publicKey;
@@ -34,10 +35,11 @@ public class AccountData {
 		this.level = level;
 		this.blocksMinted = blocksMinted;
 		this.blocksMintedAdjustment = blocksMintedAdjustment;
+		this.blocksMintedPenalty = blocksMintedPenalty;
 	}
 
 	public AccountData(String address) {
-		this(address, null, null, Group.NO_GROUP, 0, 0, 0, 0);
+		this(address, null, null, Group.NO_GROUP, 0, 0, 0, 0, 0);
 	}
 
 	// Getters/Setters
@@ -102,6 +104,14 @@ public class AccountData {
 		this.blocksMintedAdjustment = blocksMintedAdjustment;
 	}
 
+	public int getBlocksMintedPenalty() {
+		return this.blocksMintedPenalty;
+	}
+
+	public void setBlocksMintedPenalty(int blocksMintedPenalty) {
+		this.blocksMintedPenalty = blocksMintedPenalty;
+	}
+
 	// Comparison
 
 	@Override

src/main/java/org/qortal/data/account/AccountPenaltyData.java

@@ -0,0 +1,52 @@
+package org.qortal.data.account;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+
+// All properties to be converted to JSON via JAXB
+@XmlAccessorType(XmlAccessType.FIELD)
+public class AccountPenaltyData {
+
+	// Properties
+	private String address;
+	private int blocksMintedPenalty;
+
+	// Constructors
+
+	// necessary for JAXB
+	protected AccountPenaltyData() {
+	}
+
+	public AccountPenaltyData(String address, int blocksMintedPenalty) {
+		this.address = address;
+		this.blocksMintedPenalty = blocksMintedPenalty;
+	}
+
+	// Getters/Setters
+
+	public String getAddress() {
+		return this.address;
+	}
+
+	public int getBlocksMintedPenalty() {
+		return this.blocksMintedPenalty;
+	}
+
+	public String toString() {
+		return String.format("%s has penalty %d", this.address, this.blocksMintedPenalty);
+	}
+
+	@Override
+	public boolean equals(Object b) {
+		if (!(b instanceof AccountPenaltyData))
+			return false;
+
+		return this.getAddress().equals(((AccountPenaltyData) b).getAddress());
+	}
+
+	@Override
+	public int hashCode() {
+		return address.hashCode();
+	}
+
+}

src/main/java/org/qortal/data/arbitrary/ArbitraryResourceMetadata.java

@@ -24,7 +24,10 @@ public class ArbitraryResourceMetadata {
         this.description = description;
         this.tags = tags;
         this.category = category;
-        this.categoryName = category.getName();
+
+        if (category != null) {
+            this.categoryName = category.getName();
+        }
     }
 
     public static ArbitraryResourceMetadata fromTransactionMetadata(ArbitraryDataTransactionMetadata transactionMetadata) {

src/main/java/org/qortal/data/block/BlockData.java

@@ -211,6 +211,14 @@ public class BlockData implements Serializable {
 		this.onlineAccountsSignatures = onlineAccountsSignatures;
 	}
 
+	public int getOnlineAccountsSignaturesCount() {
+		if (this.onlineAccountsSignatures != null && this.onlineAccountsSignatures.length > 0) {
+			// Blocks use a single online accounts signature, so there is no need for this to be dynamic
+			return 1;
+		}
+		return 0;
+	}
+
 	public boolean isTrimmed() {
 		long onlineAccountSignaturesTrimmedTimestamp = NTP.getTime() - BlockChain.getInstance().getOnlineAccountSignaturesMaxLifetime();
 		long currentTrimmableTimestamp = NTP.getTime() - Settings.getInstance().getAtStatesMaxLifetime();

src/main/java/org/qortal/data/block/BlockSummaryData.java

@@ -11,11 +11,12 @@ public class BlockSummaryData {
 	private int height;
 	private byte[] signature;
 	private byte[] minterPublicKey;
-	private int onlineAccountsCount;
 
 	// Optional, set during construction
+	private Integer onlineAccountsCount;
 	private Long timestamp;
 	private Integer transactionCount;
+	private byte[] reference;
 
 	// Optional, set after construction
 	private Integer minterLevel;
@@ -25,6 +26,15 @@ public class BlockSummaryData {
 	protected BlockSummaryData() {
 	}
 
+	/** Constructor typically populated with fields from HeightV2Message */
+	public BlockSummaryData(int height, byte[] signature, byte[] minterPublicKey, long timestamp) {
+		this.height = height;
+		this.signature = signature;
+		this.minterPublicKey = minterPublicKey;
+		this.timestamp = timestamp;
+	}
+
+	/** Constructor typically populated with fields from BlockSummariesMessage */
 	public BlockSummaryData(int height, byte[] signature, byte[] minterPublicKey, int onlineAccountsCount) {
 		this.height = height;
 		this.signature = signature;
@@ -32,13 +42,16 @@ public class BlockSummaryData {
 		this.onlineAccountsCount = onlineAccountsCount;
 	}
 
-	public BlockSummaryData(int height, byte[] signature, byte[] minterPublicKey, int onlineAccountsCount, long timestamp, int transactionCount) {
+	/** Constructor typically populated with fields from BlockSummariesV2Message */
+	public BlockSummaryData(int height, byte[] signature, byte[] minterPublicKey, Integer onlineAccountsCount,
+							Long timestamp, Integer transactionCount, byte[] reference) {
 		this.height = height;
 		this.signature = signature;
 		this.minterPublicKey = minterPublicKey;
 		this.onlineAccountsCount = onlineAccountsCount;
 		this.timestamp = timestamp;
 		this.transactionCount = transactionCount;
+		this.reference = reference;
 	}
 
 	public BlockSummaryData(BlockData blockData) {
@@ -49,6 +62,7 @@ public class BlockSummaryData {
 
 		this.timestamp = blockData.getTimestamp();
 		this.transactionCount = blockData.getTransactionCount();
+		this.reference = blockData.getReference();
 	}
 
 	// Getters / setters
@@ -65,7 +79,7 @@ public class BlockSummaryData {
 		return this.minterPublicKey;
 	}
 
-	public int getOnlineAccountsCount() {
+	public Integer getOnlineAccountsCount() {
 		return this.onlineAccountsCount;
 	}
 
@@ -77,6 +91,10 @@ public class BlockSummaryData {
 		return this.transactionCount;
 	}
 
+	public byte[] getReference() {
+		return this.reference;
+	}
+
 	public Integer getMinterLevel() {
 		return this.minterLevel;
 	}

src/main/java/org/qortal/data/block/CommonBlockData.java

@@ -1,7 +1,5 @@
 package org.qortal.data.block;
 
-import org.qortal.data.network.PeerChainTipData;
-
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
 import java.math.BigInteger;
@@ -14,14 +12,14 @@ public class CommonBlockData {
 	private BlockSummaryData commonBlockSummary = null;
 	private List<BlockSummaryData> blockSummariesAfterCommonBlock = null;
 	private BigInteger chainWeight = null;
-	private PeerChainTipData chainTipData = null;
+	private BlockSummaryData chainTipData = null;
 
 	// Constructors
 
 	protected CommonBlockData() {
 	}
 
-	public CommonBlockData(BlockSummaryData commonBlockSummary, PeerChainTipData chainTipData) {
+	public CommonBlockData(BlockSummaryData commonBlockSummary, BlockSummaryData chainTipData) {
 		this.commonBlockSummary = commonBlockSummary;
 		this.chainTipData = chainTipData;
 	}
@@ -49,7 +47,7 @@ public class CommonBlockData {
 		this.chainWeight = chainWeight;
 	}
 
-	public PeerChainTipData getChainTipData() {
+	public BlockSummaryData getChainTipData() {
 		return this.chainTipData;
 	}
 

src/main/java/org/qortal/data/chat/ChatMessage.java

@@ -27,6 +27,8 @@ public class ChatMessage {
 
 	private String recipientName;
 
+	private byte[] chatReference;
+
 	private byte[] data;
 
 	private boolean isText;
@@ -42,8 +44,8 @@ public class ChatMessage {
 
 	// For repository use
 	public ChatMessage(long timestamp, int txGroupId, byte[] reference, byte[] senderPublicKey, String sender,
-			String senderName, String recipient, String recipientName, byte[] data, boolean isText,
-			boolean isEncrypted, byte[] signature) {
+			String senderName, String recipient, String recipientName, byte[] chatReference, byte[] data,
+			boolean isText, boolean isEncrypted, byte[] signature) {
 		this.timestamp = timestamp;
 		this.txGroupId = txGroupId;
 		this.reference = reference;
@@ -52,6 +54,7 @@ public class ChatMessage {
 		this.senderName = senderName;
 		this.recipient = recipient;
 		this.recipientName = recipientName;
+		this.chatReference = chatReference;
 		this.data = data;
 		this.isText = isText;
 		this.isEncrypted = isEncrypted;
@@ -90,6 +93,10 @@ public class ChatMessage {
 		return this.recipientName;
 	}
 
+	public byte[] getChatReference() {
+		return this.chatReference;
+	}
+
 	public byte[] getData() {
 		return this.data;
 	}

src/main/java/org/qortal/data/network/OnlineAccountData.java

@@ -16,6 +16,7 @@ public class OnlineAccountData {
 	protected long timestamp;
 	protected byte[] signature;
 	protected byte[] publicKey;
+	protected Integer nonce;
 
 	@XmlTransient
 	private int hash;
@@ -26,10 +27,15 @@ public class OnlineAccountData {
 	protected OnlineAccountData() {
 	}
 
-	public OnlineAccountData(long timestamp, byte[] signature, byte[] publicKey) {
+	public OnlineAccountData(long timestamp, byte[] signature, byte[] publicKey, Integer nonce) {
 		this.timestamp = timestamp;
 		this.signature = signature;
 		this.publicKey = publicKey;
+		this.nonce = nonce;
+	}
+
+	public OnlineAccountData(long timestamp, byte[] signature, byte[] publicKey) {
+		this(timestamp, signature, publicKey, null);
 	}
 
 	public long getTimestamp() {
@@ -44,6 +50,10 @@ public class OnlineAccountData {
 		return this.publicKey;
 	}
 
+	public Integer getNonce() {
+		return this.nonce;
+	}
+
 	// For JAXB
 	@XmlElement(name = "address")
 	protected String getAddress() {

src/main/java/org/qortal/data/network/PeerChainTipData.java

@@ -1,37 +0,0 @@
-package org.qortal.data.network;
-
-public class PeerChainTipData {
-
-	/** Latest block height as reported by peer. */
-	private Integer lastHeight;
-	/** Latest block signature as reported by peer. */
-	private byte[] lastBlockSignature;
-	/** Latest block timestamp as reported by peer. */
-	private Long lastBlockTimestamp;
-	/** Latest block minter public key as reported by peer. */
-	private byte[] lastBlockMinter;
-
-	public PeerChainTipData(Integer lastHeight, byte[] lastBlockSignature, Long lastBlockTimestamp, byte[] lastBlockMinter) {
-		this.lastHeight = lastHeight;
-		this.lastBlockSignature = lastBlockSignature;
-		this.lastBlockTimestamp = lastBlockTimestamp;
-		this.lastBlockMinter = lastBlockMinter;
-	}
-
-	public Integer getLastHeight() {
-		return this.lastHeight;
-	}
-
-	public byte[] getLastBlockSignature() {
-		return this.lastBlockSignature;
-	}
-
-	public Long getLastBlockTimestamp() {
-		return this.lastBlockTimestamp;
-	}
-
-	public byte[] getLastBlockMinter() {
-		return this.lastBlockMinter;
-	}
-
-}

src/main/java/org/qortal/data/network/PeerData.java

@@ -28,6 +28,9 @@ public class PeerData {
 	private Long addedWhen;
 	private String addedBy;
 
+	/** The number of consecutive times we failed to sync with this peer */
+	private int failedSyncCount = 0;
+
 	// Constructors
 
 	// necessary for JAXB serialization
@@ -92,6 +95,18 @@ public class PeerData {
 		return this.addedBy;
 	}
 
+	public int getFailedSyncCount() {
+		return this.failedSyncCount;
+	}
+
+	public void setFailedSyncCount(int failedSyncCount) {
+		this.failedSyncCount = failedSyncCount;
+	}
+
+	public void incrementFailedSyncCount() {
+		this.failedSyncCount++;
+	}
+
 	// Pretty peerAddress getter for JAXB
 	@XmlElement(name = "address")
 	protected String getPrettyAddress() {

src/main/java/org/qortal/data/transaction/ChatTransactionData.java

@@ -26,6 +26,8 @@ public class ChatTransactionData extends TransactionData {
 
 	private String recipient; // can be null
 
+	private byte[] chatReference; // can be null
+
 	@Schema(description = "raw message data, possibly UTF8 text", example = "2yGEbwRFyhPZZckKA")
 	private byte[] data;
 
@@ -44,13 +46,14 @@ public class ChatTransactionData extends TransactionData {
 	}
 
 	public ChatTransactionData(BaseTransactionData baseTransactionData,
-			String sender, int nonce, String recipient, byte[] data, boolean isText, boolean isEncrypted) {
+			String sender, int nonce, String recipient, byte[] chatReference, byte[] data, boolean isText, boolean isEncrypted) {
 		super(TransactionType.CHAT, baseTransactionData);
 
 		this.senderPublicKey = baseTransactionData.creatorPublicKey;
 		this.sender = sender;
 		this.nonce = nonce;
 		this.recipient = recipient;
+		this.chatReference = chatReference;
 		this.data = data;
 		this.isText = isText;
 		this.isEncrypted = isEncrypted;
@@ -78,6 +81,14 @@ public class ChatTransactionData extends TransactionData {
 		return this.recipient;
 	}
 
+	public byte[] getChatReference() {
+		return this.chatReference;
+	}
+
+	public void setChatReference(byte[] chatReference) {
+		this.chatReference = chatReference;
+	}
+
 	public byte[] getData() {
 		return this.data;
 	}

src/main/java/org/qortal/data/transaction/DeployAtTransactionData.java

@@ -2,6 +2,7 @@ package org.qortal.data.transaction;
 
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
 
 import org.qortal.transaction.Transaction.TransactionType;
@@ -90,4 +91,17 @@ public class DeployAtTransactionData extends TransactionData {
 		this.aTAddress = AtAddress;
 	}
 
+	// Re-expose creatorPublicKey for this transaction type for JAXB
+	@XmlElement(name = "creatorPublicKey")
+	@Schema(name = "creatorPublicKey", description = "AT creator's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	public byte[] getAtCreatorPublicKey() {
+		return this.creatorPublicKey;
+	}
+
+	@XmlElement(name = "creatorPublicKey")
+	@Schema(name = "creatorPublicKey", description = "AT creator's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	public void setAtCreatorPublicKey(byte[] creatorPublicKey) {
+		this.creatorPublicKey = creatorPublicKey;
+	}
+
 }

src/main/java/org/qortal/data/transaction/TransactionData.java

@@ -128,6 +128,10 @@ public abstract class TransactionData {
 		return this.txGroupId;
 	}
 
+	public void setTxGroupId(int txGroupId) {
+		this.txGroupId = txGroupId;
+	}
+
 	public byte[] getReference() {
 		return this.reference;
 	}

src/main/java/org/qortal/group/Group.java

@@ -80,6 +80,9 @@ public class Group {
 	// Useful constants
 	public static final int NO_GROUP = 0;
 
+	// Null owner address corresponds with public key "11111111111111111111111111111111"
+	public static String NULL_OWNER_ADDRESS = "QdSnUy6sUiEnaN87dWmE92g1uQjrvPgrWG";
+
 	public static final int MIN_NAME_SIZE = 3;
 	public static final int MAX_NAME_SIZE = 32;
 	public static final int MAX_DESCRIPTION_SIZE = 128;

src/main/java/org/qortal/network/Handshake.java

@@ -265,7 +265,7 @@ public enum Handshake {
 	private static final long PEER_VERSION_131 = 0x0100030001L;
 
 	/** Minimum peer version that we are allowed to communicate with */
-	private static final String MIN_PEER_VERSION = "3.1.0";
+	private static final String MIN_PEER_VERSION = "3.8.2";
 
 	private static final int POW_BUFFER_SIZE_PRE_131 = 8 * 1024 * 1024; // bytes
 	private static final int POW_DIFFICULTY_PRE_131 = 8; // leading zero bits

src/main/java/org/qortal/network/Network.java

@@ -11,6 +11,7 @@ import org.qortal.controller.arbitrary.ArbitraryDataFileListManager;
 import org.qortal.controller.arbitrary.ArbitraryDataManager;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.block.BlockData;
+import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.network.PeerData;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.network.message.*;
@@ -90,6 +91,8 @@ public class Network {
 
     private static final long DISCONNECTION_CHECK_INTERVAL = 10 * 1000L; // milliseconds
 
+    private static final int BROADCAST_CHAIN_TIP_DEPTH = 7; // Just enough to fill a SINGLE TCP packet (~1440 bytes)
+
     // Generate our node keys / ID
     private final Ed25519PrivateKeyParameters edPrivateKeyParams = new Ed25519PrivateKeyParameters(new SecureRandom());
     private final Ed25519PublicKeyParameters edPublicKeyParams = edPrivateKeyParams.generatePublicKey();
@@ -1087,10 +1090,16 @@ public class Network {
 
         if (peer.isOutbound()) {
             if (!Settings.getInstance().isLite()) {
-                // Send our height
-                Message heightMessage = buildHeightMessage(peer, Controller.getInstance().getChainTip());
-                if (!peer.sendMessage(heightMessage)) {
-                    peer.disconnect("failed to send height/info");
+                // Send our height / chain tip info
+                Message message = this.buildHeightOrChainTipInfo(peer);
+
+                if (message == null) {
+                    peer.disconnect("Couldn't build our chain tip info");
+                    return;
+                }
+
+                if (!peer.sendMessage(message)) {
+                    peer.disconnect("failed to send height / chain tip info");
                     return;
                 }
             }
@@ -1164,10 +1173,47 @@ public class Network {
         return new PeersV2Message(peerAddresses);
     }
 
-    public Message buildHeightMessage(Peer peer, BlockData blockData) {
-        // HEIGHT_V2 contains way more useful info
-        return new HeightV2Message(blockData.getHeight(), blockData.getSignature(),
-                blockData.getTimestamp(), blockData.getMinterPublicKey());
+    /** Builds either (legacy) HeightV2Message or (newer) BlockSummariesV2Message, depending on peer version.
+     *
+     *  @return Message, or null if DataException was thrown.
+     */
+    public Message buildHeightOrChainTipInfo(Peer peer) {
+        if (peer.getPeersVersion() >= BlockSummariesV2Message.MINIMUM_PEER_VERSION) {
+            int latestHeight = Controller.getInstance().getChainHeight();
+
+            try (final Repository repository = RepositoryManager.getRepository()) {
+                List<BlockSummaryData> latestBlockSummaries = repository.getBlockRepository().getBlockSummaries(latestHeight - BROADCAST_CHAIN_TIP_DEPTH, latestHeight);
+                return new BlockSummariesV2Message(latestBlockSummaries);
+            } catch (DataException e) {
+                return null;
+            }
+        } else {
+            // For older peers
+            BlockData latestBlockData = Controller.getInstance().getChainTip();
+            return new HeightV2Message(latestBlockData.getHeight(), latestBlockData.getSignature(),
+                    latestBlockData.getTimestamp(), latestBlockData.getMinterPublicKey());
+        }
+    }
+
+    public void broadcastOurChain() {
+        BlockData latestBlockData = Controller.getInstance().getChainTip();
+        int latestHeight = latestBlockData.getHeight();
+
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            List<BlockSummaryData> latestBlockSummaries = repository.getBlockRepository().getBlockSummaries(latestHeight - BROADCAST_CHAIN_TIP_DEPTH, latestHeight);
+            Message latestBlockSummariesMessage = new BlockSummariesV2Message(latestBlockSummaries);
+
+            // For older peers
+            Message heightMessage = new HeightV2Message(latestBlockData.getHeight(), latestBlockData.getSignature(),
+                    latestBlockData.getTimestamp(), latestBlockData.getMinterPublicKey());
+
+            Network.getInstance().broadcast(broadcastPeer -> broadcastPeer.getPeersVersion() >= BlockSummariesV2Message.MINIMUM_PEER_VERSION
+                    ? latestBlockSummariesMessage
+                    : heightMessage
+            );
+        } catch (DataException e) {
+            LOGGER.warn("Couldn't broadcast our chain tip info", e);
+        }
     }
 
     public Message buildNewTransactionMessage(Peer peer, TransactionData transactionData) {

src/main/java/org/qortal/network/Peer.java

@@ -6,8 +6,8 @@ import com.google.common.net.InetAddresses;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.controller.Controller;
+import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.block.CommonBlockData;
-import org.qortal.data.network.PeerChainTipData;
 import org.qortal.data.network.PeerData;
 import org.qortal.network.message.ChallengeMessage;
 import org.qortal.network.message.Message;
@@ -148,13 +148,18 @@ public class Peer {
     /**
      * Latest block info as reported by peer.
      */
-    private PeerChainTipData peersChainTipData;
+    private List<BlockSummaryData> peersChainTipData = Collections.emptyList();
 
     /**
      * Our common block with this peer
      */
     private CommonBlockData commonBlockData;
 
+    /**
+     * Last time we detected this peer as TOO_DIVERGENT
+     */
+    private Long lastTooDivergentTime;
+
     // Message stats
 
     private static class MessageStats {
@@ -353,28 +358,42 @@ public class Peer {
         }
     }
 
-    public PeerChainTipData getChainTipData() {
-        synchronized (this.peerInfoLock) {
-            return this.peersChainTipData;
-        }
+    public BlockSummaryData getChainTipData() {
+        List<BlockSummaryData> chainTipSummaries = this.peersChainTipData;
+
+        if (chainTipSummaries.isEmpty())
+            return null;
+
+        // Return last entry, which should have greatest height
+        return chainTipSummaries.get(chainTipSummaries.size() - 1);
     }
 
-    public void setChainTipData(PeerChainTipData chainTipData) {
-        synchronized (this.peerInfoLock) {
-            this.peersChainTipData = chainTipData;
-        }
+    public void setChainTipData(BlockSummaryData chainTipData) {
+        this.peersChainTipData = Collections.singletonList(chainTipData);
+    }
+
+    public List<BlockSummaryData> getChainTipSummaries() {
+        return this.peersChainTipData;
+    }
+
+    public void setChainTipSummaries(List<BlockSummaryData> chainTipSummaries) {
+        this.peersChainTipData = List.copyOf(chainTipSummaries);
     }
 
     public CommonBlockData getCommonBlockData() {
-        synchronized (this.peerInfoLock) {
-            return this.commonBlockData;
-        }
+        return this.commonBlockData;
     }
 
     public void setCommonBlockData(CommonBlockData commonBlockData) {
-        synchronized (this.peerInfoLock) {
-            this.commonBlockData = commonBlockData;
-        }
+        this.commonBlockData = commonBlockData;
+    }
+
+    public Long getLastTooDivergentTime() {
+        return this.lastTooDivergentTime;
+    }
+
+    public void setLastTooDivergentTime(Long lastTooDivergentTime) {
+        this.lastTooDivergentTime = lastTooDivergentTime;
     }
 
     public boolean isSyncInProgress() {
@@ -904,20 +923,22 @@ public class Peer {
     // Common block data
 
     public boolean canUseCachedCommonBlockData() {
-        PeerChainTipData peerChainTipData = this.getChainTipData();
-        CommonBlockData commonBlockData = this.getCommonBlockData();
+        BlockSummaryData peerChainTipData = this.getChainTipData();
+        if (peerChainTipData == null || peerChainTipData.getSignature() == null)
+            return false;
 
-        if (peerChainTipData != null && commonBlockData != null) {
-            PeerChainTipData commonBlockChainTipData = commonBlockData.getChainTipData();
-            if (peerChainTipData.getLastBlockSignature() != null && commonBlockChainTipData != null
-                    && commonBlockChainTipData.getLastBlockSignature() != null) {
-                if (Arrays.equals(peerChainTipData.getLastBlockSignature(),
-                        commonBlockChainTipData.getLastBlockSignature())) {
-                    return true;
-                }
-            }
-        }
-        return false;
+        CommonBlockData commonBlockData = this.getCommonBlockData();
+        if (commonBlockData == null)
+            return false;
+
+        BlockSummaryData commonBlockChainTipData = commonBlockData.getChainTipData();
+        if (commonBlockChainTipData == null || commonBlockChainTipData.getSignature() == null)
+            return false;
+
+        if (!Arrays.equals(peerChainTipData.getSignature(), commonBlockChainTipData.getSignature()))
+            return false;
+
+        return true;
     }
 
 

src/main/java/org/qortal/network/message/AccountMessage.java

@@ -41,6 +41,8 @@ public class AccountMessage extends Message {
 
 			bytes.write(Ints.toByteArray(accountData.getBlocksMintedAdjustment()));
 
+			bytes.write(Ints.toByteArray(accountData.getBlocksMintedPenalty()));
+
 		} catch (IOException e) {
 			throw new AssertionError("IOException shouldn't occur with ByteArrayOutputStream");
 		}
@@ -80,7 +82,9 @@ public class AccountMessage extends Message {
 
 		int blocksMintedAdjustment = byteBuffer.getInt();
 
-		AccountData accountData = new AccountData(address, reference, publicKey, defaultGroupId, flags, level, blocksMinted, blocksMintedAdjustment);
+		int blocksMintedPenalty = byteBuffer.getInt();
+
+		AccountData accountData = new AccountData(address, reference, publicKey, defaultGroupId, flags, level, blocksMinted, blocksMintedAdjustment, blocksMintedPenalty);
 		return new AccountMessage(id, accountData);
 	}
 

src/main/java/org/qortal/network/message/BlockSummariesV2Message.java

@@ -0,0 +1,109 @@
+package org.qortal.network.message;
+
+import com.google.common.primitives.Ints;
+import com.google.common.primitives.Longs;
+import org.qortal.data.block.BlockSummaryData;
+import org.qortal.transform.Transformer;
+import org.qortal.transform.block.BlockTransformer;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.BufferUnderflowException;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
+
+public class BlockSummariesV2Message extends Message {
+
+	public static final long MINIMUM_PEER_VERSION = 0x0300060001L;
+
+	private static final int BLOCK_SUMMARY_V2_LENGTH = BlockTransformer.BLOCK_SIGNATURE_LENGTH /* block signature */
+			+ Transformer.PUBLIC_KEY_LENGTH /* minter public key */
+			+ Transformer.INT_LENGTH /* online accounts count */
+			+ Transformer.LONG_LENGTH /* block timestamp */
+			+ Transformer.INT_LENGTH /* transactions count */
+			+ BlockTransformer.BLOCK_SIGNATURE_LENGTH; /* block reference */
+
+	private List<BlockSummaryData> blockSummaries;
+
+	public BlockSummariesV2Message(List<BlockSummaryData> blockSummaries) {
+		super(MessageType.BLOCK_SUMMARIES_V2);
+
+		// Shortcut for when there are no summaries
+		if (blockSummaries.isEmpty()) {
+			this.dataBytes = Message.EMPTY_DATA_BYTES;
+			return;
+		}
+
+		ByteArrayOutputStream bytes = new ByteArrayOutputStream();
+
+		try {
+			// First summary's height
+			bytes.write(Ints.toByteArray(blockSummaries.get(0).getHeight()));
+
+			for (BlockSummaryData blockSummary : blockSummaries) {
+				bytes.write(blockSummary.getSignature());
+				bytes.write(blockSummary.getMinterPublicKey());
+				bytes.write(Ints.toByteArray(blockSummary.getOnlineAccountsCount()));
+				bytes.write(Longs.toByteArray(blockSummary.getTimestamp()));
+				bytes.write(Ints.toByteArray(blockSummary.getTransactionCount()));
+				bytes.write(blockSummary.getReference());
+			}
+		} catch (IOException e) {
+			throw new AssertionError("IOException shouldn't occur with ByteArrayOutputStream");
+		}
+
+		this.dataBytes = bytes.toByteArray();
+		this.checksumBytes = Message.generateChecksum(this.dataBytes);
+	}
+
+	private BlockSummariesV2Message(int id, List<BlockSummaryData> blockSummaries) {
+		super(id, MessageType.BLOCK_SUMMARIES_V2);
+
+		this.blockSummaries = blockSummaries;
+	}
+
+	public List<BlockSummaryData> getBlockSummaries() {
+		return this.blockSummaries;
+	}
+
+	public static Message fromByteBuffer(int id, ByteBuffer bytes) {
+		List<BlockSummaryData> blockSummaries = new ArrayList<>();
+
+		// If there are no bytes remaining then we can treat this as an empty array of summaries
+		if (bytes.remaining() == 0)
+			return new BlockSummariesV2Message(id, blockSummaries);
+
+		int height = bytes.getInt();
+
+		// Expecting bytes remaining to be exact multiples of BLOCK_SUMMARY_V2_LENGTH
+		if (bytes.remaining() % BLOCK_SUMMARY_V2_LENGTH != 0)
+			throw new BufferUnderflowException();
+
+		while (bytes.hasRemaining()) {
+			byte[] signature = new byte[BlockTransformer.BLOCK_SIGNATURE_LENGTH];
+			bytes.get(signature);
+
+			byte[] minterPublicKey = new byte[Transformer.PUBLIC_KEY_LENGTH];
+			bytes.get(minterPublicKey);
+
+			int onlineAccountsCount = bytes.getInt();
+
+			long timestamp = bytes.getLong();
+
+			int transactionsCount = bytes.getInt();
+
+			byte[] reference = new byte[BlockTransformer.BLOCK_SIGNATURE_LENGTH];
+			bytes.get(reference);
+
+			BlockSummaryData blockSummary = new BlockSummaryData(height, signature, minterPublicKey,
+					onlineAccountsCount, timestamp, transactionsCount, reference);
+			blockSummaries.add(blockSummary);
+
+			height++;
+		}
+
+		return new BlockSummariesV2Message(id, blockSummaries);
+	}
+
+}

src/main/java/org/qortal/network/message/GenericUnknownMessage.java

@@ -0,0 +1,23 @@
+package org.qortal.network.message;
+
+import java.nio.ByteBuffer;
+
+public class GenericUnknownMessage extends Message {
+
+    public static final long MINIMUM_PEER_VERSION = 0x0300060001L;
+
+    public GenericUnknownMessage() {
+        super(MessageType.GENERIC_UNKNOWN);
+
+        this.dataBytes = EMPTY_DATA_BYTES;
+    }
+
+    private GenericUnknownMessage(int id) {
+        super(id, MessageType.GENERIC_UNKNOWN);
+    }
+
+    public static Message fromByteBuffer(int id, ByteBuffer bytes) {
+        return new GenericUnknownMessage(id);
+    }
+
+}

src/main/java/org/qortal/network/message/MessageType.java

@@ -21,6 +21,7 @@ public enum MessageType {
     HEIGHT_V2(10, HeightV2Message::fromByteBuffer),
     PING(11, PingMessage::fromByteBuffer),
     PONG(12, PongMessage::fromByteBuffer),
+    GENERIC_UNKNOWN(13, GenericUnknownMessage::fromByteBuffer),
 
     // Requesting data
     PEERS_V2(20, PeersV2Message::fromByteBuffer),
@@ -41,12 +42,13 @@ public enum MessageType {
 
     BLOCK_SUMMARIES(70, BlockSummariesMessage::fromByteBuffer),
     GET_BLOCK_SUMMARIES(71, GetBlockSummariesMessage::fromByteBuffer),
+    BLOCK_SUMMARIES_V2(72, BlockSummariesV2Message::fromByteBuffer),
 
     ONLINE_ACCOUNTS(80, OnlineAccountsMessage::fromByteBuffer),
     GET_ONLINE_ACCOUNTS(81, GetOnlineAccountsMessage::fromByteBuffer),
     ONLINE_ACCOUNTS_V2(82, OnlineAccountsV2Message::fromByteBuffer),
     GET_ONLINE_ACCOUNTS_V2(83, GetOnlineAccountsV2Message::fromByteBuffer),
-    // ONLINE_ACCOUNTS_V3(84, OnlineAccountsV3Message::fromByteBuffer),
+    ONLINE_ACCOUNTS_V3(84, OnlineAccountsV3Message::fromByteBuffer),
     GET_ONLINE_ACCOUNTS_V3(85, GetOnlineAccountsV3Message::fromByteBuffer),
 
     ARBITRARY_DATA(90, ArbitraryDataMessage::fromByteBuffer),

src/main/java/org/qortal/network/message/OnlineAccountsV3Message.java

@@ -0,0 +1,121 @@
+package org.qortal.network.message;
+
+import com.google.common.primitives.Ints;
+import com.google.common.primitives.Longs;
+import org.qortal.data.network.OnlineAccountData;
+import org.qortal.transform.Transformer;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * For sending online accounts info to remote peer.
+ *
+ * Same format as V2, but with added support for a mempow nonce.
+ */
+public class OnlineAccountsV3Message extends Message {
+
+	public static final long MIN_PEER_VERSION = 0x300060000L; // 3.6.0
+
+	private List<OnlineAccountData> onlineAccounts;
+
+	public OnlineAccountsV3Message(List<OnlineAccountData> onlineAccounts) {
+		super(MessageType.ONLINE_ACCOUNTS_V3);
+
+		// Shortcut in case we have no online accounts
+		if (onlineAccounts.isEmpty()) {
+			this.dataBytes = Ints.toByteArray(0);
+			this.checksumBytes = Message.generateChecksum(this.dataBytes);
+			return;
+		}
+
+		// How many of each timestamp
+		Map<Long, Integer> countByTimestamp = new HashMap<>();
+
+		for (OnlineAccountData onlineAccountData : onlineAccounts) {
+			Long timestamp = onlineAccountData.getTimestamp();
+			countByTimestamp.compute(timestamp, (k, v) -> v == null ? 1 : ++v);
+		}
+
+		// We should know exactly how many bytes to allocate now
+		int byteSize = countByTimestamp.size() * (Transformer.INT_LENGTH + Transformer.TIMESTAMP_LENGTH)
+				+ onlineAccounts.size() * (Transformer.SIGNATURE_LENGTH + Transformer.PUBLIC_KEY_LENGTH);
+
+		ByteArrayOutputStream bytes = new ByteArrayOutputStream(byteSize);
+
+		try {
+			for (long timestamp : countByTimestamp.keySet()) {
+				bytes.write(Ints.toByteArray(countByTimestamp.get(timestamp)));
+
+				bytes.write(Longs.toByteArray(timestamp));
+
+				for (OnlineAccountData onlineAccountData : onlineAccounts) {
+					if (onlineAccountData.getTimestamp() == timestamp) {
+						bytes.write(onlineAccountData.getSignature());
+						bytes.write(onlineAccountData.getPublicKey());
+
+						// Nonce is optional; use -1 as placeholder if missing
+						int nonce = onlineAccountData.getNonce() != null ? onlineAccountData.getNonce() : -1;
+						bytes.write(Ints.toByteArray(nonce));
+					}
+				}
+			}
+		} catch (IOException e) {
+			throw new AssertionError("IOException shouldn't occur with ByteArrayOutputStream");
+		}
+
+		this.dataBytes = bytes.toByteArray();
+		this.checksumBytes = Message.generateChecksum(this.dataBytes);
+	}
+
+	private OnlineAccountsV3Message(int id, List<OnlineAccountData> onlineAccounts) {
+		super(id, MessageType.ONLINE_ACCOUNTS_V3);
+
+		this.onlineAccounts = onlineAccounts;
+	}
+
+	public List<OnlineAccountData> getOnlineAccounts() {
+		return this.onlineAccounts;
+	}
+
+	public static Message fromByteBuffer(int id, ByteBuffer bytes) throws MessageException {
+		int accountCount = bytes.getInt();
+
+		List<OnlineAccountData> onlineAccounts = new ArrayList<>(accountCount);
+
+		while (accountCount > 0) {
+			long timestamp = bytes.getLong();
+
+			for (int i = 0; i < accountCount; ++i) {
+				byte[] signature = new byte[Transformer.SIGNATURE_LENGTH];
+				bytes.get(signature);
+
+				byte[] publicKey = new byte[Transformer.PUBLIC_KEY_LENGTH];
+				bytes.get(publicKey);
+
+				// Nonce is optional - will be -1 if missing
+				Integer nonce = bytes.getInt();
+				if (nonce < 0) {
+					nonce = null;
+				}
+
+				onlineAccounts.add(new OnlineAccountData(timestamp, signature, publicKey, nonce));
+			}
+
+			if (bytes.hasRemaining()) {
+				accountCount = bytes.getInt();
+			} else {
+				// we've finished
+				accountCount = 0;
+			}
+		}
+
+		return new OnlineAccountsV3Message(id, onlineAccounts);
+	}
+
+}

src/main/java/org/qortal/repository/AccountRepository.java

@@ -1,13 +1,9 @@
 package org.qortal.repository;
 
 import java.util.List;
+import java.util.Set;
 
-import org.qortal.data.account.AccountBalanceData;
-import org.qortal.data.account.AccountData;
-import org.qortal.data.account.EligibleQoraHolderData;
-import org.qortal.data.account.MintingAccountData;
-import org.qortal.data.account.QortFromQoraData;
-import org.qortal.data.account.RewardShareData;
+import org.qortal.data.account.*;
 
 public interface AccountRepository {
 
@@ -19,6 +15,9 @@ public interface AccountRepository {
 	/** Returns accounts with <b>any</b> bit set in given mask. */
 	public List<AccountData> getFlaggedAccounts(int mask) throws DataException;
 
+	/** Returns accounts with a blockedMintedPenalty */
+	public List<AccountData> getPenaltyAccounts() throws DataException;
+
 	/** Returns account's last reference or null if not set or account not found. */
 	public byte[] getLastReference(String address) throws DataException;
 
@@ -100,6 +99,18 @@ public interface AccountRepository {
 	 */
 	public void modifyMintedBlockCounts(List<String> addresses, int delta) throws DataException;
 
+	/** Returns account's block minted penalty count or null if account not found. */
+	public Integer getBlocksMintedPenaltyCount(String address) throws DataException;
+
+	/**
+	 * Sets blocks minted penalties for given list of accounts.
+	 * This replaces the existing values rather than modifying them by a delta.
+	 *
+	 * @param accountPenalties
+	 * @throws DataException
+	 */
+	public void updateBlocksMintedPenalties(Set<AccountPenaltyData> accountPenalties) throws DataException;
+
 	/** Delete account from repository. */
 	public void delete(String address) throws DataException;
 

src/main/java/org/qortal/repository/ArbitraryRepository.java

@@ -24,7 +24,7 @@ public interface ArbitraryRepository {
 	public ArbitraryTransactionData getLatestTransaction(String name, Service service, Method method, String identifier) throws DataException;
 
 
-	public List<ArbitraryResourceInfo> getArbitraryResources(Service service, String identifier, String name, boolean defaultResource, Integer limit, Integer offset, Boolean reverse) throws DataException;
+	public List<ArbitraryResourceInfo> getArbitraryResources(Service service, String identifier, List<String> names, boolean defaultResource, Integer limit, Integer offset, Boolean reverse) throws DataException;
 
 	public List<ArbitraryResourceInfo> searchArbitraryResources(Service service, String query, boolean defaultResource, Integer limit, Integer offset, Boolean reverse) throws DataException;
 

src/main/java/org/qortal/repository/ChatRepository.java

@@ -14,8 +14,8 @@ public interface ChatRepository {
 	 * Expects EITHER non-null txGroupID OR non-null sender and recipient addresses.
 	 */
 	public List<ChatMessage> getMessagesMatchingCriteria(Long before, Long after,
-			Integer txGroupId, List<String> involving,
-			Integer limit, Integer offset, Boolean reverse) throws DataException;
+			Integer txGroupId, byte[] reference, byte[] chatReferenceBytes, Boolean hasChatReference,
+			List<String> involving, Integer limit, Integer offset, Boolean reverse) throws DataException;
 
 	public ChatMessage toChatMessage(ChatTransactionData chatTransactionData) throws DataException;
 

src/main/java/org/qortal/repository/GroupRepository.java

@@ -131,7 +131,14 @@ public interface GroupRepository {
 
 	public GroupBanData getBan(int groupId, String member) throws DataException;
 
-	public boolean banExists(int groupId, String offender) throws DataException;
+	/**
+	 * IMPORTANT: when using banExists() as part of validation, the timestamp must be that of the transaction that
+	 * is calling banExists() as part of its validation. It must NOT be the current time, unless this is being
+	 * called outside of validation, as part of an on demand check for a ban existing (such as via an API call).
+	 * This is because we need to evaluate a ban's status based on the time of the subsequent transaction, as
+	 * validation will not occur at a fixed time for every node. For some, it could be months into the future.
+	 */
+	public boolean banExists(int groupId, String offender, long timestamp) throws DataException;
 
 	public List<GroupBanData> getGroupBans(int groupId, Integer limit, Integer offset, Boolean reverse) throws DataException;
 

src/main/java/org/qortal/repository/TransactionRepository.java

@@ -179,6 +179,15 @@ public interface TransactionRepository {
 	public List<TransferAssetTransactionData> getAssetTransfers(long assetId, String address, Integer limit, Integer offset, Boolean reverse)
 			throws DataException;
 
+	/**
+	 * Returns list of reward share transaction creators, excluding self shares.
+	 * This uses confirmed transactions only.
+	 *
+	 * @return
+	 * @throws DataException
+	 */
+	public List<String> getConfirmedRewardShareCreatorsExcludingSelfShares() throws DataException;
+
 	/**
 	 * Returns list of transactions pending approval, with optional txGgroupId filtering.
 	 * <p>

src/main/java/org/qortal/repository/hsqldb/HSQLDBAccountRepository.java

@@ -6,15 +6,11 @@ import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 import org.qortal.asset.Asset;
-import org.qortal.data.account.AccountBalanceData;
-import org.qortal.data.account.AccountData;
-import org.qortal.data.account.EligibleQoraHolderData;
-import org.qortal.data.account.MintingAccountData;
-import org.qortal.data.account.QortFromQoraData;
-import org.qortal.data.account.RewardShareData;
+import org.qortal.data.account.*;
 import org.qortal.repository.AccountRepository;
 import org.qortal.repository.DataException;
 
@@ -30,7 +26,7 @@ public class HSQLDBAccountRepository implements AccountRepository {
 
 	@Override
 	public AccountData getAccount(String address) throws DataException {
-		String sql = "SELECT reference, public_key, default_group_id, flags, level, blocks_minted, blocks_minted_adjustment FROM Accounts WHERE account = ?";
+		String sql = "SELECT reference, public_key, default_group_id, flags, level, blocks_minted, blocks_minted_adjustment, blocks_minted_penalty FROM Accounts WHERE account = ?";
 
 		try (ResultSet resultSet = this.repository.checkedExecute(sql, address)) {
 			if (resultSet == null)
@@ -43,8 +39,9 @@ public class HSQLDBAccountRepository implements AccountRepository {
 			int level = resultSet.getInt(5);
 			int blocksMinted = resultSet.getInt(6);
 			int blocksMintedAdjustment = resultSet.getInt(7);
+			int blocksMintedPenalty = resultSet.getInt(8);
 
-			return new AccountData(address, reference, publicKey, defaultGroupId, flags, level, blocksMinted, blocksMintedAdjustment);
+			return new AccountData(address, reference, publicKey, defaultGroupId, flags, level, blocksMinted, blocksMintedAdjustment, blocksMintedPenalty);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch account info from repository", e);
 		}
@@ -52,7 +49,7 @@ public class HSQLDBAccountRepository implements AccountRepository {
 
 	@Override
 	public List<AccountData> getFlaggedAccounts(int mask) throws DataException {
-		String sql = "SELECT reference, public_key, default_group_id, flags, level, blocks_minted, blocks_minted_adjustment, account FROM Accounts WHERE BITAND(flags, ?) != 0";
+		String sql = "SELECT reference, public_key, default_group_id, flags, level, blocks_minted, blocks_minted_adjustment, blocks_minted_penalty, account FROM Accounts WHERE BITAND(flags, ?) != 0";
 
 		List<AccountData> accounts = new ArrayList<>();
 
@@ -68,9 +65,10 @@ public class HSQLDBAccountRepository implements AccountRepository {
 				int level = resultSet.getInt(5);
 				int blocksMinted = resultSet.getInt(6);
 				int blocksMintedAdjustment = resultSet.getInt(7);
-				String address = resultSet.getString(8);
+				int blocksMintedPenalty = resultSet.getInt(8);
+				String address = resultSet.getString(9);
 
-				accounts.add(new AccountData(address, reference, publicKey, defaultGroupId, flags, level, blocksMinted, blocksMintedAdjustment));
+				accounts.add(new AccountData(address, reference, publicKey, defaultGroupId, flags, level, blocksMinted, blocksMintedAdjustment, blocksMintedPenalty));
 			} while (resultSet.next());
 
 			return accounts;
@@ -79,6 +77,36 @@ public class HSQLDBAccountRepository implements AccountRepository {
 		}
 	}
 
+	@Override
+	public List<AccountData> getPenaltyAccounts() throws DataException {
+		String sql = "SELECT reference, public_key, default_group_id, flags, level, blocks_minted, blocks_minted_adjustment, blocks_minted_penalty, account FROM Accounts WHERE blocks_minted_penalty != 0";
+
+		List<AccountData> accounts = new ArrayList<>();
+
+		try (ResultSet resultSet = this.repository.checkedExecute(sql)) {
+			if (resultSet == null)
+				return accounts;
+
+			do {
+				byte[] reference = resultSet.getBytes(1);
+				byte[] publicKey = resultSet.getBytes(2);
+				int defaultGroupId = resultSet.getInt(3);
+				int flags = resultSet.getInt(4);
+				int level = resultSet.getInt(5);
+				int blocksMinted = resultSet.getInt(6);
+				int blocksMintedAdjustment = resultSet.getInt(7);
+				int blocksMintedPenalty = resultSet.getInt(8);
+				String address = resultSet.getString(9);
+
+				accounts.add(new AccountData(address, reference, publicKey, defaultGroupId, flags, level, blocksMinted, blocksMintedAdjustment, blocksMintedPenalty));
+			} while (resultSet.next());
+
+			return accounts;
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch penalty accounts from repository", e);
+		}
+	}
+
 	@Override
 	public byte[] getLastReference(String address) throws DataException {
 		String sql = "SELECT reference FROM Accounts WHERE account = ?";
@@ -298,6 +326,39 @@ public class HSQLDBAccountRepository implements AccountRepository {
 		}
 	}
 
+	@Override
+	public Integer getBlocksMintedPenaltyCount(String address) throws DataException {
+		String sql = "SELECT blocks_minted_penalty FROM Accounts WHERE account = ?";
+
+		try (ResultSet resultSet = this.repository.checkedExecute(sql, address)) {
+			if (resultSet == null)
+				return null;
+
+			return resultSet.getInt(1);
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch account's block minted penalty count from repository", e);
+		}
+	}
+	public void updateBlocksMintedPenalties(Set<AccountPenaltyData> accountPenalties) throws DataException {
+		// Nothing to do?
+		if (accountPenalties == null || accountPenalties.isEmpty())
+			return;
+
+		// Map balance changes into SQL bind params, filtering out no-op changes
+		List<Object[]> updateBlocksMintedPenaltyParams = accountPenalties.stream()
+				.map(accountPenalty -> new Object[] { accountPenalty.getAddress(), accountPenalty.getBlocksMintedPenalty(), accountPenalty.getBlocksMintedPenalty() })
+				.collect(Collectors.toList());
+
+		// Perform actual balance changes
+		String sql = "INSERT INTO Accounts (account, blocks_minted_penalty) VALUES (?, ?) " +
+				"ON DUPLICATE KEY UPDATE blocks_minted_penalty = blocks_minted_penalty + ?";
+		try {
+			this.repository.executeCheckedBatchUpdate(sql, updateBlocksMintedPenaltyParams);
+		} catch (SQLException e) {
+			throw new DataException("Unable to set blocks minted penalties in repository", e);
+		}
+	}
+
 	@Override
 	public void delete(String address) throws DataException {
 		// NOTE: Account balances are deleted automatically by the database thanks to "ON DELETE CASCADE" in AccountBalances' FOREIGN KEY

src/main/java/org/qortal/repository/hsqldb/HSQLDBArbitraryRepository.java

@@ -301,7 +301,7 @@ public class HSQLDBArbitraryRepository implements ArbitraryRepository {
 	}
 
 	@Override
-	public List<ArbitraryResourceInfo> getArbitraryResources(Service service, String identifier, String name,
+	public List<ArbitraryResourceInfo> getArbitraryResources(Service service, String identifier, List<String> names,
 															 boolean defaultResource, Integer limit, Integer offset, Boolean reverse) throws DataException {
 		StringBuilder sql = new StringBuilder(512);
 		List<Object> bindParams = new ArrayList<>();
@@ -325,9 +325,16 @@ public class HSQLDBArbitraryRepository implements ArbitraryRepository {
 			bindParams.add(identifier);
 		}
 
-		if (name != null) {
-			sql.append(" AND name = ?");
-			bindParams.add(name);
+		if (names != null && !names.isEmpty()) {
+			sql.append(" AND name IN (?");
+			bindParams.add(names.get(0));
+
+			for (int i = 1; i < names.size(); ++i) {
+				sql.append(", ?");
+				bindParams.add(names.get(i));
+			}
+
+			sql.append(")");
 		}
 
 		sql.append(" GROUP BY name, service, identifier ORDER BY name COLLATE SQL_TEXT_UCC_NO_PAD");

src/main/java/org/qortal/repository/hsqldb/HSQLDBBlockArchiveRepository.java

@@ -143,13 +143,17 @@ public class HSQLDBBlockArchiveRepository implements BlockArchiveRepository {
                 byte[] blockMinterPublicKey = resultSet.getBytes(3);
 
                 // Fetch additional info from the archive itself
-                int onlineAccountsCount = 0;
+                Integer onlineAccountsCount = null;
+                Long timestamp = null;
+                Integer transactionCount = null;
+                byte[] reference = null;
+
                 BlockData blockData = this.fromSignature(signature);
                 if (blockData != null) {
                     onlineAccountsCount = blockData.getOnlineAccountsCount();
                 }
 
-                BlockSummaryData blockSummary = new BlockSummaryData(height, signature, blockMinterPublicKey, onlineAccountsCount);
+                BlockSummaryData blockSummary = new BlockSummaryData(height, signature, blockMinterPublicKey, onlineAccountsCount, timestamp, transactionCount, reference);
                 blockSummaries.add(blockSummary);
             } while (resultSet.next());
 

src/main/java/org/qortal/repository/hsqldb/HSQLDBBlockRepository.java

@@ -297,7 +297,7 @@ public class HSQLDBBlockRepository implements BlockRepository {
 	@Override
 	public List<BlockSummaryData> getBlockSummariesBySigner(byte[] signerPublicKey, Integer limit, Integer offset, Boolean reverse) throws DataException {
 		StringBuilder sql = new StringBuilder(512);
-		sql.append("SELECT signature, height, Blocks.minter, online_accounts_count FROM ");
+		sql.append("SELECT signature, height, Blocks.minter, online_accounts_count, minted_when, transaction_count, Blocks.reference FROM ");
 
 		// List of minter account's public key and reward-share public keys with minter's public key
 		sql.append("(SELECT * FROM (VALUES (CAST(? AS QortalPublicKey))) UNION (SELECT reward_share_public_key FROM RewardShares WHERE minter_public_key = ?)) AS PublicKeys (public_key) ");
@@ -322,8 +322,12 @@ public class HSQLDBBlockRepository implements BlockRepository {
 				int height = resultSet.getInt(2);
 				byte[] blockMinterPublicKey = resultSet.getBytes(3);
 				int onlineAccountsCount = resultSet.getInt(4);
+				long timestamp = resultSet.getLong(5);
+				int transactionCount = resultSet.getInt(6);
+				byte[] reference = resultSet.getBytes(7);
 
-				BlockSummaryData blockSummary = new BlockSummaryData(height, signature, blockMinterPublicKey, onlineAccountsCount);
+				BlockSummaryData blockSummary = new BlockSummaryData(height, signature, blockMinterPublicKey, onlineAccountsCount,
+						timestamp, transactionCount, reference);
 				blockSummaries.add(blockSummary);
 			} while (resultSet.next());
 
@@ -355,7 +359,7 @@ public class HSQLDBBlockRepository implements BlockRepository {
 
 	@Override
 	public List<BlockSummaryData> getBlockSummaries(int firstBlockHeight, int lastBlockHeight) throws DataException {
-		String sql = "SELECT signature, height, minter, online_accounts_count, minted_when, transaction_count "
+		String sql = "SELECT signature, height, minter, online_accounts_count, minted_when, transaction_count, reference "
 				+ "FROM Blocks WHERE height BETWEEN ? AND ?";
 
 		List<BlockSummaryData> blockSummaries = new ArrayList<>();
@@ -371,9 +375,10 @@ public class HSQLDBBlockRepository implements BlockRepository {
 				int onlineAccountsCount = resultSet.getInt(4);
 				long timestamp = resultSet.getLong(5);
 				int transactionCount = resultSet.getInt(6);
+				byte[] reference = resultSet.getBytes(7);
 
 				BlockSummaryData blockSummary = new BlockSummaryData(height, signature, minterPublicKey, onlineAccountsCount,
-						timestamp, transactionCount);
+						timestamp, transactionCount, reference);
 				blockSummaries.add(blockSummary);
 			} while (resultSet.next());
 

src/main/java/org/qortal/repository/hsqldb/HSQLDBChatRepository.java

@@ -23,9 +23,9 @@ public class HSQLDBChatRepository implements ChatRepository {
 	}
 
 	@Override
-	public List<ChatMessage> getMessagesMatchingCriteria(Long before, Long after, Integer txGroupId,
-			List<String> involving, Integer limit, Integer offset, Boolean reverse)
-			throws DataException {
+	public List<ChatMessage> getMessagesMatchingCriteria(Long before, Long after, Integer txGroupId, byte[] referenceBytes,
+			byte[] chatReferenceBytes, Boolean hasChatReference, List<String> involving,
+			Integer limit, Integer offset, Boolean reverse) throws DataException {
 		// Check args meet expectations
 		if ((txGroupId != null && involving != null && !involving.isEmpty())
 				|| (txGroupId == null && (involving == null || involving.size() != 2)))
@@ -35,7 +35,7 @@ public class HSQLDBChatRepository implements ChatRepository {
 
 		sql.append("SELECT created_when, tx_group_id, Transactions.reference, creator, "
 				+ "sender, SenderNames.name, recipient, RecipientNames.name, "
-				+ "data, is_text, is_encrypted, signature "
+				+ "chat_reference, data, is_text, is_encrypted, signature "
 				+ "FROM ChatTransactions "
 				+ "JOIN Transactions USING (signature) "
 				+ "LEFT OUTER JOIN Names AS SenderNames ON SenderNames.owner = sender "
@@ -57,6 +57,23 @@ public class HSQLDBChatRepository implements ChatRepository {
 			bindParams.add(after);
 		}
 
+		if (referenceBytes != null) {
+			whereClauses.add("reference = ?");
+			bindParams.add(referenceBytes);
+		}
+
+		if (chatReferenceBytes != null) {
+			whereClauses.add("chat_reference = ?");
+			bindParams.add(chatReferenceBytes);
+		}
+
+		if (hasChatReference != null && hasChatReference == true) {
+			whereClauses.add("chat_reference IS NOT NULL");
+		}
+		else if (hasChatReference != null && hasChatReference == false) {
+			whereClauses.add("chat_reference IS NULL");
+		}
+
 		if (txGroupId != null) {
 			whereClauses.add("tx_group_id = " + txGroupId); // int safe to use literally
 			whereClauses.add("recipient IS NULL");
@@ -98,13 +115,14 @@ public class HSQLDBChatRepository implements ChatRepository {
 				String senderName = resultSet.getString(6);
 				String recipient = resultSet.getString(7);
 				String recipientName = resultSet.getString(8);
-				byte[] data = resultSet.getBytes(9);
-				boolean isText = resultSet.getBoolean(10);
-				boolean isEncrypted = resultSet.getBoolean(11);
-				byte[] signature = resultSet.getBytes(12);
+				byte[] chatReference = resultSet.getBytes(9);
+				byte[] data = resultSet.getBytes(10);
+				boolean isText = resultSet.getBoolean(11);
+				boolean isEncrypted = resultSet.getBoolean(12);
+				byte[] signature = resultSet.getBytes(13);
 
 				ChatMessage chatMessage = new ChatMessage(timestamp, groupId, reference, senderPublicKey, sender,
-						senderName, recipient, recipientName, data, isText, isEncrypted, signature);
+						senderName, recipient, recipientName, chatReference, data, isText, isEncrypted, signature);
 
 				chatMessages.add(chatMessage);
 			} while (resultSet.next());
@@ -136,13 +154,14 @@ public class HSQLDBChatRepository implements ChatRepository {
 			byte[] senderPublicKey = chatTransactionData.getSenderPublicKey();
 			String sender = chatTransactionData.getSender();
 			String recipient = chatTransactionData.getRecipient();
+			byte[] chatReference = chatTransactionData.getChatReference();
 			byte[] data = chatTransactionData.getData();
 			boolean isText = chatTransactionData.getIsText();
 			boolean isEncrypted = chatTransactionData.getIsEncrypted();
 			byte[] signature = chatTransactionData.getSignature();
 
 			return new ChatMessage(timestamp, groupId, reference, senderPublicKey, sender,
-					senderName, recipient, recipientName, data, isText, isEncrypted, signature);
+					senderName, recipient, recipientName, chatReference, data, isText, isEncrypted, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch convert chat transaction from repository", e);
 		}

src/main/java/org/qortal/repository/hsqldb/HSQLDBDatabaseUpdates.java

@@ -975,6 +975,19 @@ public class HSQLDBDatabaseUpdates {
 					stmt.execute("ALTER TABLE TradeBotStates ALTER COLUMN receiving_account_info SET DATA TYPE VARBINARY(128)");
 					break;
 
+				case 44:
+					// Add blocks minted penalty
+					stmt.execute("ALTER TABLE Accounts ADD blocks_minted_penalty INTEGER NOT NULL DEFAULT 0");
+					break;
+
+				case 45:
+					// Add a chat reference, to allow one message to reference another, and for this to be easily
+					// searchable. Null values are allowed as most transactions won't have a reference.
+					stmt.execute("ALTER TABLE ChatTransactions ADD chat_reference Signature");
+					// For finding chat messages by reference
+					stmt.execute("CREATE INDEX ChatTransactionsChatReferenceIndex ON ChatTransactions (chat_reference)");
+					break;
+
 				default:
 					// nothing to do
 					return false;

src/main/java/org/qortal/repository/hsqldb/HSQLDBGroupRepository.java

@@ -777,9 +777,9 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public boolean banExists(int groupId, String offender) throws DataException {
+	public boolean banExists(int groupId, String offender, long timestamp) throws DataException {
 		try {
-			return this.repository.exists("GroupBans", "group_id = ? AND offender = ?", groupId, offender);
+			return this.repository.exists("GroupBans", "group_id = ? AND offender = ? AND (expires_when IS NULL OR expires_when > ?)", groupId, offender, timestamp);
 		} catch (SQLException e) {
 			throw new DataException("Unable to check for group ban in repository", e);
 		}

src/main/java/org/qortal/repository/hsqldb/transaction/HSQLDBChatTransactionRepository.java

@@ -17,7 +17,7 @@ public class HSQLDBChatTransactionRepository extends HSQLDBTransactionRepository
 	}
 
 	TransactionData fromBase(BaseTransactionData baseTransactionData) throws DataException {
-		String sql = "SELECT sender, nonce, recipient, is_text, is_encrypted, data FROM ChatTransactions WHERE signature = ?";
+		String sql = "SELECT sender, nonce, recipient, is_text, is_encrypted, data, chat_reference FROM ChatTransactions WHERE signature = ?";
 
 		try (ResultSet resultSet = this.repository.checkedExecute(sql, baseTransactionData.getSignature())) {
 			if (resultSet == null)
@@ -29,8 +29,9 @@ public class HSQLDBChatTransactionRepository extends HSQLDBTransactionRepository
 			boolean isText = resultSet.getBoolean(4);
 			boolean isEncrypted = resultSet.getBoolean(5);
 			byte[] data = resultSet.getBytes(6);
+			byte[] chatReference = resultSet.getBytes(7);
 
-			return new ChatTransactionData(baseTransactionData, sender, nonce, recipient, data, isText, isEncrypted);
+			return new ChatTransactionData(baseTransactionData, sender, nonce, recipient, chatReference, data, isText, isEncrypted);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch chat transaction from repository", e);
 		}
@@ -45,7 +46,7 @@ public class HSQLDBChatTransactionRepository extends HSQLDBTransactionRepository
 		saveHelper.bind("signature", chatTransactionData.getSignature()).bind("nonce", chatTransactionData.getNonce())
 				.bind("sender", chatTransactionData.getSender()).bind("recipient", chatTransactionData.getRecipient())
 				.bind("is_text", chatTransactionData.getIsText()).bind("is_encrypted", chatTransactionData.getIsEncrypted())
-				.bind("data", chatTransactionData.getData());
+				.bind("data", chatTransactionData.getData()).bind("chat_reference", chatTransactionData.getChatReference());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qortal/repository/hsqldb/transaction/HSQLDBTransactionRepository.java

@@ -7,11 +7,7 @@ import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.sql.ResultSet;
 import java.sql.SQLException;
-import java.util.ArrayList;
-import java.util.EnumMap;
-import java.util.EnumSet;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -969,6 +965,33 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 		}
 	}
 
+	public List<String> getConfirmedRewardShareCreatorsExcludingSelfShares() throws DataException {
+		List<String> rewardShareCreators = new ArrayList<>();
+
+		String sql = "SELECT account "
+				+ "FROM RewardShareTransactions "
+				+ "JOIN Accounts ON Accounts.public_key = RewardShareTransactions.minter_public_key "
+				+ "JOIN Transactions ON Transactions.signature = RewardShareTransactions.signature "
+				+ "WHERE block_height IS NOT NULL AND RewardShareTransactions.recipient != Accounts.account "
+				+ "GROUP BY account "
+				+ "ORDER BY account";
+
+		try (ResultSet resultSet = this.repository.checkedExecute(sql)) {
+			if (resultSet == null)
+				return rewardShareCreators;
+
+			do {
+				String address = resultSet.getString(1);
+
+				rewardShareCreators.add(address);
+			} while (resultSet.next());
+
+			return rewardShareCreators;
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch reward share creators from repository", e);
+		}
+	}
+
 	@Override
 	public List<TransactionData> getApprovalPendingTransactions(Integer txGroupId, Integer limit, Integer offset, Boolean reverse) throws DataException {
 		StringBuilder sql = new StringBuilder(512);

src/main/java/org/qortal/settings/Settings.java

@@ -110,7 +110,13 @@ public class Settings {
 	/** Maximum number of unconfirmed transactions allowed per account */
 	private int maxUnconfirmedPerAccount = 25;
 	/** Max milliseconds into future for accepting new, unconfirmed transactions */
-	private int maxTransactionTimestampFuture = 24 * 60 * 60 * 1000; // milliseconds
+	private int maxTransactionTimestampFuture = 30 * 60 * 1000; // milliseconds
+
+	/** Maximum number of CHAT transactions allowed per account in recent timeframe */
+	private int maxRecentChatMessagesPerAccount = 250;
+	/** Maximum age of a CHAT transaction to be considered 'recent' */
+	private long recentChatMessagesMaxAge = 60 * 60 * 1000L; // milliseconds
+
 	/** Whether we check, fetch and install auto-updates */
 	private boolean autoUpdateEnabled = true;
 	/** How long between repository backups (ms), or 0 if disabled. */
@@ -153,7 +159,7 @@ public class Settings {
 	 * This prevents the node from being able to serve older blocks */
 	private boolean topOnly = false;
 	/** The amount of recent blocks we should keep when pruning */
-	private int pruneBlockLimit = 1450;
+	private int pruneBlockLimit = 6000;
 
 	/** How often to attempt AT state pruning (ms). */
 	private long atStatesPruneInterval = 3219L; // milliseconds
@@ -184,6 +190,8 @@ public class Settings {
 
 	// Peer-to-peer related
 	private boolean isTestNet = false;
+	/** Single node testnet mode */
+	private boolean singleNodeTestnet = false;
 	/** Port number for inbound peer-to-peer connections. */
 	private Integer listenPort;
 	/** Whether to attempt to open the listen port via UPnP */
@@ -203,8 +211,11 @@ public class Settings {
 	/** Maximum number of retry attempts if a peer fails to respond with the requested data */
 	private int maxRetries = 2;
 
+	/** The number of seconds of no activity before recovery mode begins */
+	public long recoveryModeTimeout = 10 * 60 * 1000L;
+
 	/** Minimum peer version number required in order to sync with them */
-	private String minPeerVersion = "3.3.7";
+	private String minPeerVersion = "3.8.2";
 	/** Whether to allow connections with peers below minPeerVersion
 	 * If true, we won't sync with them but they can still sync with us, and will show in the peers list
 	 * If false, sync will be blocked both ways, and they will not appear in the peers list */
@@ -262,7 +273,7 @@ public class Settings {
 	private String[] bootstrapHosts = new String[] {
 			"http://bootstrap.qortal.org",
 			"http://bootstrap2.qortal.org",
-			"http://62.171.190.193"
+			"http://bootstrap.qortal.online"
 	};
 
 	// Auto-update sources
@@ -291,6 +302,7 @@ public class Settings {
 	private Long testNtpOffset = null;
 
 
+
 	/* Foreign chains */
 
 	/** The number of consecutive empty addresses required before treating a wallet's transaction set as complete */
@@ -485,7 +497,7 @@ public class Settings {
 
 	private void validate() {
 		// Validation goes here
-		if (this.minBlockchainPeers < 1)
+		if (this.minBlockchainPeers < 1 && !singleNodeTestnet)
 			throwValidationError("minBlockchainPeers must be at least 1");
 
 		if (this.apiKey != null && this.apiKey.trim().length() < 8)
@@ -634,6 +646,14 @@ public class Settings {
 		return this.maxTransactionTimestampFuture;
 	}
 
+	public int getMaxRecentChatMessagesPerAccount() {
+		return this.maxRecentChatMessagesPerAccount;
+	}
+
+	public long getRecentChatMessagesMaxAge() {
+		return recentChatMessagesMaxAge;
+	}
+
 	public int getBlockCacheSize() {
 		return this.blockCacheSize;
 	}
@@ -642,6 +662,10 @@ public class Settings {
 		return this.isTestNet;
 	}
 
+	public boolean isSingleNodeTestnet() {
+		return this.singleNodeTestnet;
+	}
+
 	public int getListenPort() {
 		if (this.listenPort != null)
 			return this.listenPort;
@@ -662,6 +686,9 @@ public class Settings {
 	}
 
 	public int getMinBlockchainPeers() {
+		if (singleNodeTestnet)
+			return 0;
+
 		return this.minBlockchainPeers;
 	}
 
@@ -687,6 +714,10 @@ public class Settings {
 
 	public int getMaxRetries() { return this.maxRetries; }
 
+	public long getRecoveryModeTimeout() {
+		return recoveryModeTimeout;
+	}
+
 	public String getMinPeerVersion() { return this.minPeerVersion; }
 
 	public boolean getAllowConnectionsWithOlderPeerVersions() { return this.allowConnectionsWithOlderPeerVersions; }

src/main/java/org/qortal/transaction/AddGroupAdminTransaction.java

@@ -2,6 +2,7 @@ package org.qortal.transaction;
 
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 
 import org.qortal.account.Account;
 import org.qortal.asset.Asset;
@@ -64,15 +65,24 @@ public class AddGroupAdminTransaction extends Transaction {
 
 		Account owner = getOwner();
 		String groupOwner = this.repository.getGroupRepository().getOwner(groupId);
+		boolean groupOwnedByNullAccount = Objects.equals(groupOwner, Group.NULL_OWNER_ADDRESS);
 
-		// Check transaction's public key matches group's current owner
-		if (!owner.getAddress().equals(groupOwner))
+		// Require approval if transaction relates to a group owned by the null account
+		if (groupOwnedByNullAccount && !this.needsGroupApproval())
+			return ValidationResult.GROUP_APPROVAL_REQUIRED;
+
+		// Check transaction's public key matches group's current owner (except for groups owned by the null account)
+		if (!groupOwnedByNullAccount && !owner.getAddress().equals(groupOwner))
 			return ValidationResult.INVALID_GROUP_OWNER;
 
 		// Check address is a group member
 		if (!this.repository.getGroupRepository().memberExists(groupId, memberAddress))
 			return ValidationResult.NOT_GROUP_MEMBER;
 
+		// Check transaction creator is a group member
+		if (!this.repository.getGroupRepository().memberExists(groupId, this.getCreator().getAddress()))
+			return ValidationResult.NOT_GROUP_MEMBER;
+
 		// Check group member is not already an admin
 		if (this.repository.getGroupRepository().adminExists(groupId, memberAddress))
 			return ValidationResult.ALREADY_GROUP_ADMIN;

src/main/java/org/qortal/transaction/ArbitraryTransaction.java

@@ -24,6 +24,7 @@ import org.qortal.transform.Transformer;
 import org.qortal.transform.transaction.ArbitraryTransactionTransformer;
 import org.qortal.transform.transaction.TransactionTransformer;
 import org.qortal.utils.ArbitraryTransactionUtils;
+import org.qortal.utils.NTP;
 
 public class ArbitraryTransaction extends Transaction {
 
@@ -34,9 +35,13 @@ public class ArbitraryTransaction extends Transaction {
 	public static final int MAX_DATA_SIZE = 4000;
 	public static final int MAX_METADATA_LENGTH = 32;
 	public static final int HASH_LENGTH = TransactionTransformer.SHA256_LENGTH;
-	public static final int POW_BUFFER_SIZE = 8 * 1024 * 1024; // bytes
 	public static final int MAX_IDENTIFIER_LENGTH = 64;
 
+	/** If time difference between transaction and now is greater than this then we don't verify proof-of-work. */
+	public static final long HISTORIC_THRESHOLD = 2 * 7 * 24 * 60 * 60 * 1000L;
+	public static final int POW_BUFFER_SIZE = 8 * 1024 * 1024; // bytes
+
+
 	// Constructors
 
 	public ArbitraryTransaction(Repository repository, TransactionData transactionData) {
@@ -202,9 +207,11 @@ public class ArbitraryTransaction extends Transaction {
 			// Clear nonce from transactionBytes
 			ArbitraryTransactionTransformer.clearNonce(transactionBytes);
 
-			// Check nonce
-			int difficulty = ArbitraryDataManager.getInstance().getPowDifficulty();
-			return MemoryPoW.verify2(transactionBytes, POW_BUFFER_SIZE, difficulty, nonce);
+			// We only need to check nonce for recent transactions due to PoW verification overhead
+			if (NTP.getTime() - this.arbitraryTransactionData.getTimestamp() < HISTORIC_THRESHOLD) {
+				int difficulty = ArbitraryDataManager.getInstance().getPowDifficulty();
+				return MemoryPoW.verify2(transactionBytes, POW_BUFFER_SIZE, difficulty, nonce);
+			}
 		}
 
 		return true;

src/main/java/org/qortal/transaction/CancelGroupBanTransaction.java

@@ -73,7 +73,7 @@ public class CancelGroupBanTransaction extends Transaction {
 		Account member = getMember();
 
 		// Check ban actually exists
-		if (!this.repository.getGroupRepository().banExists(groupId, member.getAddress()))
+		if (!this.repository.getGroupRepository().banExists(groupId, member.getAddress(), this.groupUnbanTransactionData.getTimestamp()))
 			return ValidationResult.BAN_UNKNOWN;
 
 		// Check admin has enough funds

src/main/java/org/qortal/transaction/ChatTransaction.java

@@ -1,7 +1,9 @@
 package org.qortal.transaction;
 
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.function.Predicate;
 
 import org.qortal.account.Account;
 import org.qortal.account.PublicKeyAccount;
@@ -16,9 +18,11 @@ import org.qortal.list.ResourceListManager;
 import org.qortal.repository.DataException;
 import org.qortal.repository.GroupRepository;
 import org.qortal.repository.Repository;
+import org.qortal.settings.Settings;
 import org.qortal.transform.TransformationException;
 import org.qortal.transform.transaction.ChatTransactionTransformer;
 import org.qortal.transform.transaction.TransactionTransformer;
+import org.qortal.utils.NTP;
 
 public class ChatTransaction extends Transaction {
 
@@ -26,10 +30,11 @@ public class ChatTransaction extends Transaction {
 	private ChatTransactionData chatTransactionData;
 
 	// Other useful constants
-	public static final int MAX_DATA_SIZE = 256;
+	public static final int MAX_DATA_SIZE = 4000;
 	public static final int POW_BUFFER_SIZE = 8 * 1024 * 1024; // bytes
-	public static final int POW_DIFFICULTY_WITH_QORT = 8; // leading zero bits
-	public static final int POW_DIFFICULTY_NO_QORT = 12; // leading zero bits
+	public static final int POW_DIFFICULTY_ABOVE_QORT_THRESHOLD = 8; // leading zero bits
+	public static final int POW_DIFFICULTY_BELOW_QORT_THRESHOLD = 18; // leading zero bits
+	public static final long POW_QORT_THRESHOLD = 400000000L;
 
 	// Constructors
 
@@ -78,7 +83,7 @@ public class ChatTransaction extends Transaction {
 		// Clear nonce from transactionBytes
 		ChatTransactionTransformer.clearNonce(transactionBytes);
 
-		int difficulty = this.getSender().getConfirmedBalance(Asset.QORT) > 0 ? POW_DIFFICULTY_WITH_QORT : POW_DIFFICULTY_NO_QORT;
+		int difficulty = this.getSender().getConfirmedBalance(Asset.QORT) >= POW_QORT_THRESHOLD ? POW_DIFFICULTY_ABOVE_QORT_THRESHOLD : POW_DIFFICULTY_BELOW_QORT_THRESHOLD;
 
 		// Calculate nonce
 		this.chatTransactionData.setNonce(MemoryPoW.compute2(transactionBytes, POW_BUFFER_SIZE, difficulty));
@@ -145,6 +150,11 @@ public class ChatTransaction extends Transaction {
 	public ValidationResult isValid() throws DataException {
 		// Nonce checking is done via isSignatureValid() as that method is only called once per import
 
+		// Disregard messages with timestamp too far in the future (we have stricter limits for CHAT transactions)
+		if (this.chatTransactionData.getTimestamp() > NTP.getTime() + (5 * 60 * 1000L)) {
+			return ValidationResult.TIMESTAMP_TOO_NEW;
+		}
+
 		// Check for blocked author by address
 		ResourceListManager listManager = ResourceListManager.getInstance();
 		if (listManager.listContains("blockedAddresses", this.chatTransactionData.getSender(), true)) {
@@ -163,6 +173,14 @@ public class ChatTransaction extends Transaction {
 			}
 		}
 
+		PublicKeyAccount creator = this.getCreator();
+		if (creator == null)
+			return ValidationResult.MISSING_CREATOR;
+
+		// Reject if unconfirmed pile already has X recent CHAT transactions from same creator
+		if (countRecentChatTransactionsByCreator(creator) >= Settings.getInstance().getMaxRecentChatMessagesPerAccount())
+			return ValidationResult.TOO_MANY_UNCONFIRMED;
+
 		// If we exist in the repository then we've been imported as unconfirmed,
 		// but we don't want to make it into a block, so return fake non-OK result.
 		if (this.repository.getTransactionRepository().exists(this.chatTransactionData.getSignature()))
@@ -204,7 +222,7 @@ public class ChatTransaction extends Transaction {
 
 		int difficulty;
 		try {
-			difficulty = this.getSender().getConfirmedBalance(Asset.QORT) > 0 ? POW_DIFFICULTY_WITH_QORT : POW_DIFFICULTY_NO_QORT;
+			difficulty = this.getSender().getConfirmedBalance(Asset.QORT) >= POW_QORT_THRESHOLD ? POW_DIFFICULTY_ABOVE_QORT_THRESHOLD : POW_DIFFICULTY_BELOW_QORT_THRESHOLD;
 		} catch (DataException e) {
 			return false;
 		}
@@ -213,6 +231,26 @@ public class ChatTransaction extends Transaction {
 		return MemoryPoW.verify2(transactionBytes, POW_BUFFER_SIZE, difficulty, nonce);
 	}
 
+	private int countRecentChatTransactionsByCreator(PublicKeyAccount creator) throws DataException {
+		List<TransactionData> unconfirmedTransactions = repository.getTransactionRepository().getUnconfirmedTransactions();
+		final Long now = NTP.getTime();
+		long recentThreshold = Settings.getInstance().getRecentChatMessagesMaxAge();
+
+		// We only care about chat transactions, and only those that are considered 'recent'
+		Predicate<TransactionData> hasSameCreatorAndIsRecentChat = transactionData -> {
+			if (transactionData.getType() != TransactionType.CHAT)
+				return false;
+
+			if (transactionData.getTimestamp() < now - recentThreshold)
+				return false;
+
+			return Arrays.equals(creator.getPublicKey(), transactionData.getCreatorPublicKey());
+		};
+
+		return (int) unconfirmedTransactions.stream().filter(hasSameCreatorAndIsRecentChat).count();
+	}
+
+
 	/**
 	 * Ensure there's at least a skeleton account so people
 	 * can retrieve sender's public key using address, even if all their messages

src/main/java/org/qortal/transaction/GroupInviteTransaction.java

@@ -78,7 +78,7 @@ public class GroupInviteTransaction extends Transaction {
 			return ValidationResult.ALREADY_GROUP_MEMBER;
 
 		// Check invitee is not banned
-		if (this.repository.getGroupRepository().banExists(groupId, invitee.getAddress()))
+		if (this.repository.getGroupRepository().banExists(groupId, invitee.getAddress(), this.groupInviteTransactionData.getTimestamp()))
 			return ValidationResult.BANNED_FROM_GROUP;
 
 		// Check creator has enough funds

src/main/java/org/qortal/transaction/JoinGroupTransaction.java

@@ -53,7 +53,7 @@ public class JoinGroupTransaction extends Transaction {
 			return ValidationResult.ALREADY_GROUP_MEMBER;
 
 		// Check member is not banned
-		if (this.repository.getGroupRepository().banExists(groupId, joiner.getAddress()))
+		if (this.repository.getGroupRepository().banExists(groupId, joiner.getAddress(), this.joinGroupTransactionData.getTimestamp()))
 			return ValidationResult.BANNED_FROM_GROUP;
 
 		// Check join request doesn't already exist

src/main/java/org/qortal/transaction/PublicizeTransaction.java

@@ -4,7 +4,9 @@ import java.util.Collections;
 import java.util.List;
 
 import org.qortal.account.Account;
+import org.qortal.account.PublicKeyAccount;
 import org.qortal.api.resource.TransactionsResource.ConfirmationStatus;
+import org.qortal.asset.Asset;
 import org.qortal.crypto.MemoryPoW;
 import org.qortal.data.transaction.PublicizeTransactionData;
 import org.qortal.data.transaction.TransactionData;
@@ -26,7 +28,7 @@ public class PublicizeTransaction extends Transaction {
 	/** If time difference between transaction and now is greater than this then we don't verify proof-of-work. */
 	public static final long HISTORIC_THRESHOLD = 2 * 7 * 24 * 60 * 60 * 1000L;
 	public static final int POW_BUFFER_SIZE = 8 * 1024 * 1024; // bytes
-	public static final int POW_DIFFICULTY = 15; // leading zero bits
+	public static final int POW_DIFFICULTY = 14; // leading zero bits
 
 	// Constructors
 
@@ -102,6 +104,12 @@ public class PublicizeTransaction extends Transaction {
 			if (!verifyNonce())
 				return ValidationResult.INCORRECT_NONCE;
 
+		// Validate fee if one has been included
+		PublicKeyAccount creator = this.getCreator();
+		if (this.transactionData.getFee() > 0)
+			if (creator.getConfirmedBalance(Asset.QORT) < this.transactionData.getFee())
+				return ValidationResult.NO_BALANCE;
+
 		return ValidationResult.OK;
 	}
 

src/main/java/org/qortal/transaction/RemoveGroupAdminTransaction.java

@@ -2,6 +2,7 @@ package org.qortal.transaction;
 
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 
 import org.qortal.account.Account;
 import org.qortal.asset.Asset;
@@ -65,11 +66,21 @@ public class RemoveGroupAdminTransaction extends Transaction {
 			return ValidationResult.GROUP_DOES_NOT_EXIST;
 
 		Account owner = getOwner();
+		String groupOwner = this.repository.getGroupRepository().getOwner(groupId);
+		boolean groupOwnedByNullAccount = Objects.equals(groupOwner, Group.NULL_OWNER_ADDRESS);
 
-		// Check transaction's public key matches group's current owner
-		if (!owner.getAddress().equals(groupData.getOwner()))
+		// Require approval if transaction relates to a group owned by the null account
+		if (groupOwnedByNullAccount && !this.needsGroupApproval())
+			return ValidationResult.GROUP_APPROVAL_REQUIRED;
+
+		// Check transaction's public key matches group's current owner (except for groups owned by the null account)
+		if (!groupOwnedByNullAccount && !owner.getAddress().equals(groupOwner))
 			return ValidationResult.INVALID_GROUP_OWNER;
 
+		// Check transaction creator is a group member
+		if (!this.repository.getGroupRepository().memberExists(groupId, this.getCreator().getAddress()))
+			return ValidationResult.NOT_GROUP_MEMBER;
+
 		Account admin = getAdmin();
 
 		// Check member is an admin

src/main/java/org/qortal/transaction/RewardShareTransaction.java

@@ -163,9 +163,12 @@ public class RewardShareTransaction extends Transaction {
 				return ValidationResult.SELF_SHARE_EXISTS;
 		}
 
-		// Fee checking needed if not setting up new self-share
-		if (!(isRecipientAlsoMinter && existingRewardShareData == null))
-			// Check creator has enough funds
+		// Check creator has enough funds
+		if (this.rewardShareTransactionData.getTimestamp() >= BlockChain.getInstance().getFeeValidationFixTimestamp())
+			if (creator.getConfirmedBalance(Asset.QORT) < this.rewardShareTransactionData.getFee())
+				return ValidationResult.NO_BALANCE;
+
+		else if (!(isRecipientAlsoMinter && existingRewardShareData == null))
 			if (creator.getConfirmedBalance(Asset.QORT) < this.rewardShareTransactionData.getFee())
 				return ValidationResult.NO_BALANCE;
 

src/main/java/org/qortal/transaction/Transaction.java

@@ -1,13 +1,7 @@
 package org.qortal.transaction;
 
 import java.math.BigInteger;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Comparator;
-import java.util.EnumSet;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Predicate;
 
@@ -69,8 +63,8 @@ public abstract class Transaction {
 		AT(21, false),
 		CREATE_GROUP(22, true),
 		UPDATE_GROUP(23, true),
-		ADD_GROUP_ADMIN(24, false),
-		REMOVE_GROUP_ADMIN(25, false),
+		ADD_GROUP_ADMIN(24, true),
+		REMOVE_GROUP_ADMIN(25, true),
 		GROUP_BAN(26, false),
 		CANCEL_GROUP_BAN(27, false),
 		GROUP_KICK(28, false),
@@ -250,6 +244,8 @@ public abstract class Transaction {
 		INVALID_TIMESTAMP_SIGNATURE(95),
 		ADDRESS_BLOCKED(96),
 		NAME_BLOCKED(97),
+		GROUP_APPROVAL_REQUIRED(98),
+		ACCOUNT_NOT_TRANSFERABLE(99),
 		INVALID_BUT_OK(999),
 		NOT_YET_RELEASED(1000);
 
@@ -760,9 +756,13 @@ public abstract class Transaction {
 			// Group no longer exists? Possibly due to blockchain orphaning undoing group creation?
 			return true; // stops tx being included in block but it will eventually expire
 
+		String groupOwner = this.repository.getGroupRepository().getOwner(txGroupId);
+		boolean groupOwnedByNullAccount = Objects.equals(groupOwner, Group.NULL_OWNER_ADDRESS);
+
 		// If transaction's creator is group admin (of group with ID txGroupId) then auto-approve
+		// This is disabled for null-owned groups, since these require approval from other admins
 		PublicKeyAccount creator = this.getCreator();
-		if (groupRepository.adminExists(txGroupId, creator.getAddress()))
+		if (!groupOwnedByNullAccount && groupRepository.adminExists(txGroupId, creator.getAddress()))
 			return false;
 
 		return true;

src/main/java/org/qortal/transaction/TransferPrivsTransaction.java

@@ -67,6 +67,11 @@ public class TransferPrivsTransaction extends Transaction {
 		if (getSender().getConfirmedBalance(Asset.QORT) < this.transferPrivsTransactionData.getFee())
 			return ValidationResult.NO_BALANCE;
 
+		// Check sender doesn't have a blocksMintedPenalty, as these accounts cannot be transferred
+		AccountData senderAccountData = this.repository.getAccountRepository().getAccount(getSender().getAddress());
+		if (senderAccountData == null || senderAccountData.getBlocksMintedPenalty() != 0)
+			return ValidationResult.ACCOUNT_NOT_TRANSFERABLE;
+
 		return ValidationResult.OK;
 	}
 

src/main/java/org/qortal/transaction/UpdateGroupTransaction.java

@@ -103,7 +103,7 @@ public class UpdateGroupTransaction extends Transaction {
 		Account newOwner = getNewOwner();
 
 		// Check new owner is not banned
-		if (this.repository.getGroupRepository().banExists(this.updateGroupTransactionData.getGroupId(), newOwner.getAddress()))
+		if (this.repository.getGroupRepository().banExists(this.updateGroupTransactionData.getGroupId(), newOwner.getAddress(), this.updateGroupTransactionData.getTimestamp()))
 			return ValidationResult.BANNED_FROM_GROUP;
 
 		return ValidationResult.OK;