From 166425bee9e943ddf8c603da7e1c7d4184481276 Mon Sep 17 00:00:00 2001
From: CalDescent <caldescent@protonmail.com>
Date: Fri, 28 Oct 2022 17:20:39 +0100
Subject: [PATCH] Added feature trigger timestamp (TBC) to increase online
 accounts mempow difficulty (also TBC).

---
 src/main/java/org/qortal/block/BlockChain.java  |  7 ++++++-
 .../controller/OnlineAccountsManager.java       | 17 +++++++++++------
 src/main/resources/blockchain.json              |  3 ++-
 3 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/src/main/java/org/qortal/block/BlockChain.java b/src/main/java/org/qortal/block/BlockChain.java
index 826fdd78..5e1f44f3 100644
--- a/src/main/java/org/qortal/block/BlockChain.java
+++ b/src/main/java/org/qortal/block/BlockChain.java
@@ -73,7 +73,8 @@ public class BlockChain {
 		calcChainWeightTimestamp,
 		transactionV5Timestamp,
 		transactionV6Timestamp,
-		disableReferenceTimestamp;
+		disableReferenceTimestamp,
+		increaseOnlineAccountsDifficultyTimestamp;
 	}
 
 	// Custom transaction fees
@@ -478,6 +479,10 @@ public class BlockChain {
 		return this.featureTriggers.get(FeatureTrigger.disableReferenceTimestamp.name()).longValue();
 	}
 
+	public long getIncreaseOnlineAccountsDifficultyTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.increaseOnlineAccountsDifficultyTimestamp.name()).longValue();
+	}
+
 
 	// More complex getters for aspects that change by height or timestamp
 
diff --git a/src/main/java/org/qortal/controller/OnlineAccountsManager.java b/src/main/java/org/qortal/controller/OnlineAccountsManager.java
index 1aea118b..fd2c38df 100644
--- a/src/main/java/org/qortal/controller/OnlineAccountsManager.java
+++ b/src/main/java/org/qortal/controller/OnlineAccountsManager.java
@@ -66,7 +66,8 @@ public class OnlineAccountsManager {
 
     // MemoryPoW - mainnet
     public static final int POW_BUFFER_SIZE = 1 * 1024 * 1024; // bytes
-    public static final int POW_DIFFICULTY = 18; // leading zero bits
+    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
@@ -128,11 +129,14 @@ public class OnlineAccountsManager {
         return POW_BUFFER_SIZE;
     }
 
-    private static int getPoWDifficulty() {
+    private static int getPoWDifficulty(long timestamp) {
         if (Settings.getInstance().isTestNet())
             return POW_DIFFICULTY_TESTNET;
 
-        return POW_DIFFICULTY;
+        if (timestamp >= BlockChain.getInstance().getIncreaseOnlineAccountsDifficultyTimestamp())
+            return POW_DIFFICULTY_V2;
+
+        return POW_DIFFICULTY_V1;
     }
 
     private OnlineAccountsManager() {
@@ -628,7 +632,8 @@ public class OnlineAccountsManager {
         final long nextOnlineAccountsTimestamp = toOnlineAccountTimestamp(startTime) + getOnlineTimestampModulus();
         long timeUntilNextTimestamp = nextOnlineAccountsTimestamp - startTime;
 
-        Integer nonce = MemoryPoW.compute2(bytes, getPoWBufferSize(), getPoWDifficulty(), timeUntilNextTimestamp);
+        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);
@@ -637,7 +642,7 @@ public class OnlineAccountsManager {
 
         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(), getPoWDifficulty(), minutes, seconds, hashRate));
+                nonce, getPoWBufferSize(), difficulty, minutes, seconds, hashRate));
 
         return nonce;
     }
@@ -658,7 +663,7 @@ public class OnlineAccountsManager {
         }
 
         // Verify the nonce
-        return MemoryPoW.verify2(mempowBytes, workBuffer, getPoWBufferSize(), getPoWDifficulty(), nonce);
+        return MemoryPoW.verify2(mempowBytes, workBuffer, getPoWBufferSize(), getPoWDifficulty(onlineAccountData.getTimestamp()), nonce);
     }
 
 
diff --git a/src/main/resources/blockchain.json b/src/main/resources/blockchain.json
index 893add5e..34671c76 100644
--- a/src/main/resources/blockchain.json
+++ b/src/main/resources/blockchain.json
@@ -79,7 +79,8 @@
 		"calcChainWeightTimestamp": 1620579600000,
 		"transactionV5Timestamp": 1642176000000,
 		"transactionV6Timestamp": 9999999999999,
-		"disableReferenceTimestamp": 1655222400000
+		"disableReferenceTimestamp": 1655222400000,
+		"increaseOnlineAccountsDifficultyTimestamp": 9999999999999
 	},
 	"genesisInfo": {
 		"version": 4,