From 8b6e74d505eaa5f58cab48a1b06fa2930106e14a Mon Sep 17 00:00:00 2001 From: CalDescent Date: Wed, 8 Dec 2021 12:18:22 +0000 Subject: [PATCH] Added ACCTv3 trade bots. Identical to v1 and v2. --- .../tradebot/DogecoinACCTv3TradeBot.java | 885 ++++++++++++++++++ .../tradebot/LitecoinACCTv3TradeBot.java | 885 ++++++++++++++++++ 2 files changed, 1770 insertions(+) create mode 100644 src/main/java/org/qortal/controller/tradebot/DogecoinACCTv3TradeBot.java create mode 100644 src/main/java/org/qortal/controller/tradebot/LitecoinACCTv3TradeBot.java diff --git a/src/main/java/org/qortal/controller/tradebot/DogecoinACCTv3TradeBot.java b/src/main/java/org/qortal/controller/tradebot/DogecoinACCTv3TradeBot.java new file mode 100644 index 00000000..996097f3 --- /dev/null +++ b/src/main/java/org/qortal/controller/tradebot/DogecoinACCTv3TradeBot.java @@ -0,0 +1,885 @@ +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. + *

+ * We deal with three different independent state-spaces here: + *

+ */ +public class DogecoinACCTv3TradeBot implements AcctTradeBot { + + private static final Logger LOGGER = LogManager.getLogger(DogecoinACCTv3TradeBot.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 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 DogecoinACCTv3TradeBot instance; + + private final List 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 DogecoinACCTv3TradeBot() { + } + + public static synchronized DogecoinACCTv3TradeBot getInstance() { + if (instance == null) + instance = new DogecoinACCTv3TradeBot(); + + return instance; + } + + @Override + public List getEndStates() { + return this.endStates; + } + + /** + * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for DOGE. + *

+ * Generates: + *

    + *
  • new 'trade' private key
    • + *
+ * Derives: + *
    + *
  • 'native' (as in Qortal) public key, public key hash, address (starting with Q)
    • + *
  • 'foreign' (as in Dogecoin) public key, public key hash
    • + *
+ * A Qortal AT is then constructed including the following as constants in the 'data segment': + *
    + *
  • 'native'/Qortal 'trade' address - used as a MESSAGE contact
    • + *
  • 'foreign'/Dogecoin public key hash - used by Alice's P2SH scripts to allow redeem
    • + *
  • QORT amount on offer by Bob
    • + *
  • DOGE amount expected in return by Bob (from Alice)
    • + *
  • trading timeout, in case things go wrong and everyone needs to refund
    • + *
+ * Returns a DEPLOY_AT transaction that needs to be signed and broadcast to the Qortal network. + *

+ * Trade-bot will wait for Bob's AT to be deployed before taking next step. + *

+ * @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 = DogecoinACCTv3.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, DogecoinACCTv3.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. + *

+ * Requires a chosen trade offer from Bob, passed by crossChainTradeData + * and access to a Dogecoin wallet via xprv58. + *

+ * The crossChainTradeData contains the current trade offer state + * as extracted from the AT's data segment. + *

+ * Access to a funded wallet is via a Dogecoin BIP32 hierarchical deterministic key, + * passed via xprv58. + * This key will be stored in your node's database + * 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). + *

+ * As an example, the xprv58 can be extract from a legacy, password-less + * Electrum wallet by going to the console tab and entering:
+ * wallet.keystore.xprv
+ * which should result in a base58 string starting with either 'xprv' (for Dogecoin main-net) + * or 'tprv' for (Dogecoin test-net). + *

+ * It is envisaged that the value in xprv58 will actually come from a Qortal-UI-managed wallet. + *

+ * If sufficient funds are available, this method will actually fund the P2SH-A + * with the Dogecoin amount expected by 'Bob'. + *

+ * 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. + *

+ * The trade-bot entry is saved to the repository and the cross-chain trading process commences. + *

+ * @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, DogecoinACCTv3.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 = DogecoinACCTv3.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 = DogecoinACCTv3.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. + *

+ * 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. + *

+ * 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. + *

+ * Assuming trade is still on offer, trade-bot checks the contents of MESSAGE from Alice's trade-bot. + *

+ * Details from Alice are used to derive P2SH-A address and this is checked for funding balance. + *

+ * 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. + *

+ * On processing this MESSAGE, Bob's AT should switch into 'TRADE' mode and only trade with Alice. + *

+ * 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 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(); + DogecoinACCTv3.OfferMessageData offerMessageData = DogecoinACCTv3.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 = DogecoinACCTv3.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 = DogecoinACCTv3.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. + *

+ * 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. + *

+ * Assuming Bob's AT is locked to Alice, trade-bot checks AT's state data to make sure it is correct. + *

+ * If all is well, trade-bot then redeems AT using Alice's secret-A, releasing Bob's QORT to Alice. + *

+ * In revealing a valid secret-A, Bob can then redeem the DOGE funds from P2SH-A. + *

+ * @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 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 = DogecoinACCTv3.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 = DogecoinACCTv3.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. + *

+ * 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. + *

+ * 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. + *

+ * (This could potentially be 'improved' to send DOGE to any address of Bob's choosing by changing the transaction output). + *

+ * 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 = DogecoinACCTv3.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 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 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. + *

+ * Will automatically update trade-bot state to ALICE_REFUNDING_A or ALICE_DONE 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; + } + +} diff --git a/src/main/java/org/qortal/controller/tradebot/LitecoinACCTv3TradeBot.java b/src/main/java/org/qortal/controller/tradebot/LitecoinACCTv3TradeBot.java new file mode 100644 index 00000000..a31a1a28 --- /dev/null +++ b/src/main/java/org/qortal/controller/tradebot/LitecoinACCTv3TradeBot.java @@ -0,0 +1,885 @@ +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. + *

+ * We deal with three different independent state-spaces here: + *

    + *
  • Qortal blockchain
    • + *
  • Foreign blockchain
    • + *
  • Trade-bot entries
    • + *
+ */ +public class LitecoinACCTv3TradeBot implements AcctTradeBot { + + private static final Logger LOGGER = LogManager.getLogger(LitecoinACCTv3TradeBot.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 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 LitecoinACCTv3TradeBot instance; + + private final List 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 LitecoinACCTv3TradeBot() { + } + + public static synchronized LitecoinACCTv3TradeBot getInstance() { + if (instance == null) + instance = new LitecoinACCTv3TradeBot(); + + return instance; + } + + @Override + public List getEndStates() { + return this.endStates; + } + + /** + * Creates a new trade-bot entry from the "Bob" viewpoint, i.e. OFFERing QORT in exchange for LTC. + *

+ * Generates: + *

    + *
  • new 'trade' private key
    • + *
+ * Derives: + *
    + *
  • 'native' (as in Qortal) public key, public key hash, address (starting with Q)
    • + *
  • 'foreign' (as in Litecoin) public key, public key hash
    • + *
+ * A Qortal AT is then constructed including the following as constants in the 'data segment': + *
    + *
  • 'native'/Qortal 'trade' address - used as a MESSAGE contact
    • + *
  • 'foreign'/Litecoin public key hash - used by Alice's P2SH scripts to allow redeem
    • + *
  • QORT amount on offer by Bob
    • + *
  • LTC amount expected in return by Bob (from Alice)
    • + *
  • trading timeout, in case things go wrong and everyone needs to refund
    • + *
+ * Returns a DEPLOY_AT transaction that needs to be signed and broadcast to the Qortal network. + *

+ * Trade-bot will wait for Bob's AT to be deployed before taking next step. + *

+ * @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 = LitecoinACCTv3.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, LitecoinACCTv3.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. + *

+ * Requires a chosen trade offer from Bob, passed by crossChainTradeData + * and access to a Litecoin wallet via xprv58. + *

+ * The crossChainTradeData contains the current trade offer state + * as extracted from the AT's data segment. + *

+ * Access to a funded wallet is via a Litecoin BIP32 hierarchical deterministic key, + * passed via xprv58. + * This key will be stored in your node's database + * 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). + *

+ * As an example, the xprv58 can be extract from a legacy, password-less + * Electrum wallet by going to the console tab and entering:
+ * wallet.keystore.xprv
+ * which should result in a base58 string starting with either 'xprv' (for Litecoin main-net) + * or 'tprv' for (Litecoin test-net). + *

+ * It is envisaged that the value in xprv58 will actually come from a Qortal-UI-managed wallet. + *

+ * If sufficient funds are available, this method will actually fund the P2SH-A + * with the Litecoin amount expected by 'Bob'. + *

+ * 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. + *

+ * The trade-bot entry is saved to the repository and the cross-chain trading process commences. + *

+ * @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, LitecoinACCTv3.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 = LitecoinACCTv3.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 = LitecoinACCTv3.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. + *

+ * 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. + *

+ * 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. + *

+ * Assuming trade is still on offer, trade-bot checks the contents of MESSAGE from Alice's trade-bot. + *

+ * Details from Alice are used to derive P2SH-A address and this is checked for funding balance. + *

+ * 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. + *

+ * On processing this MESSAGE, Bob's AT should switch into 'TRADE' mode and only trade with Alice. + *

+ * 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 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(); + LitecoinACCTv3.OfferMessageData offerMessageData = LitecoinACCTv3.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 = LitecoinACCTv3.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 = LitecoinACCTv3.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. + *

+ * 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. + *

+ * Assuming Bob's AT is locked to Alice, trade-bot checks AT's state data to make sure it is correct. + *

+ * If all is well, trade-bot then redeems AT using Alice's secret-A, releasing Bob's QORT to Alice. + *

+ * In revealing a valid secret-A, Bob can then redeem the LTC funds from P2SH-A. + *

+ * @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 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 = LitecoinACCTv3.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 = LitecoinACCTv3.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. + *

+ * 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. + *

+ * 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. + *

+ * (This could potentially be 'improved' to send LTC to any address of Bob's choosing by changing the transaction output). + *

+ * 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 = LitecoinACCTv3.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 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 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. + *

+ * Will automatically update trade-bot state to ALICE_REFUNDING_A or ALICE_DONE 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; + } + +}