Initial skeleton code for Trade Bot

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

@@ -238,9 +238,11 @@ public class Controller extends Thread {
 		return this.chainTip;
 	}
 
-	/** Cache new blockchain tip. */
+	/** Cache new blockchain tip, maybe call trade-bot. */
 	public void setChainTip(BlockData blockData) {
 		this.chainTip = blockData;
+
+		TradeBot.getInstance().onChainTipChange();
 	}
 
 	public ReentrantLock getBlockchainLock() {

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

@@ -0,0 +1,27 @@
+package org.qortal.controller;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+public class TradeBot {
+
+	private static final Logger LOGGER = LogManager.getLogger(TradeBot.class);
+
+	private static TradeBot instance;
+
+	private TradeBot() {
+		
+	}
+
+	public static synchronized TradeBot getInstance() {
+		if (instance == null)
+			instance = new TradeBot();
+
+		return instance;
+	}
+
+	public void onChainTipChange() {
+		// Get repo for trade situations
+	}
+
+}

src/main/java/org/qortal/data/crosschain/TradeBotData.java

@@ -0,0 +1,97 @@
+package org.qortal.data.crosschain;
+
+import static java.util.Arrays.stream;
+import static java.util.stream.Collectors.toMap;
+
+import java.util.Map;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlTransient;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+// All properties to be converted to JSON via JAXB
+@XmlAccessorType(XmlAccessType.FIELD)
+public class TradeBotData {
+
+	public enum State {
+		BOB_START(0), BOB_WAITING_FOR_P2SH_A(10), BOB_WAITING_FOR_P2SH_B(20), BOB_WAITING_FOR_AT_REDEEM(30),
+		ALICE_START(100), ALICE_WAITING_FOR_P2SH_A(110), ALICE_WAITING_FOR_AT_LOCK(120), ALICE_WATCH_P2SH_B(130);
+
+		public final int value;
+		private static final Map<Integer, State> map = stream(State.values()).collect(toMap(state -> state.value, state -> state));
+
+		State(int value) {
+			this.value = value;
+		}
+
+		public static State valueOf(int value) {
+			return map.get(value);
+		}
+	}
+
+	private State tradeState;
+
+	// Never expose this
+	@XmlTransient
+	@Schema(hidden = true)
+	private byte[] tradePrivateKey;
+
+	private byte[] secret;
+
+	private String atAddress;
+
+	private byte[] lastTransactionSignature;
+
+	public TradeBotData(byte[] tradePrivateKey, State tradeState, byte[] secret, String atAddress,
+			byte[] lastTransactionSignature) {
+		this.tradePrivateKey = tradePrivateKey;
+		this.tradeState = tradeState;
+		this.secret = secret;
+		this.atAddress = atAddress;
+		this.lastTransactionSignature = lastTransactionSignature;
+	}
+
+	public TradeBotData(byte[] tradePrivateKey, State tradeState) {
+		this.tradePrivateKey = tradePrivateKey;
+		this.tradeState = tradeState;
+	}
+
+	public State getState() {
+		return this.tradeState;
+	}
+
+	public void setState(State state) {
+		this.tradeState = state;
+	}
+
+	public byte[] getSecret() {
+		return this.secret;
+	}
+
+	public void setSecret(byte[] secret) {
+		this.secret = secret;
+	}
+
+	public byte[] getTradePrivateKey() {
+		return this.tradePrivateKey;
+	}
+
+	public String getAtAddress() {
+		return this.atAddress;
+	}
+
+	public void setAtAddress(String atAddress) {
+		this.atAddress = atAddress;
+	}
+
+	public byte[] getLastTransactionSignature() {
+		return this.lastTransactionSignature;
+	}
+
+	public void setLastTransactionSignature(byte[] lastTransactionSignature) {
+		this.lastTransactionSignature = lastTransactionSignature;
+	}
+
+}

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

@@ -0,0 +1,11 @@
+package org.qortal.repository;
+
+import java.util.List;
+
+import org.qortal.data.crosschain.TradeBotData;
+
+public interface CrossChainRepository {
+
+	public List<TradeBotData> getAllTradeBotData() throws DataException;
+
+}

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

@@ -14,6 +14,8 @@ public interface Repository extends AutoCloseable {
 
 	public ChatRepository getChatRepository();
 
+	public CrossChainRepository getCrossChainRepository();
+
 	public GroupRepository getGroupRepository();
 
 	public NameRepository getNameRepository();

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

@@ -0,0 +1,52 @@
+package org.qortal.repository.hsqldb;
+
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.qortal.data.crosschain.TradeBotData;
+import org.qortal.repository.CrossChainRepository;
+import org.qortal.repository.DataException;
+
+public class HSQLDBCrossChainRepository implements CrossChainRepository {
+
+	protected HSQLDBRepository repository;
+
+	public HSQLDBCrossChainRepository(HSQLDBRepository repository) {
+		this.repository = repository;
+	}
+
+	@Override
+	public List<TradeBotData> getAllTradeBotData() throws DataException {
+		String sql = "SELECT trade_private_key, trade_state, secret, at_address, last_transaction_signature "
+				+ "FROM TradeBotStates";
+
+		List<TradeBotData> allTradeBotData = new ArrayList<>();
+
+		try (ResultSet resultSet = this.repository.checkedExecute(sql)) {
+			if (resultSet == null)
+				return allTradeBotData;
+
+			do {
+				byte[] tradePrivateKey = resultSet.getBytes(1);
+				int tradeStateValue = resultSet.getInt(2);
+				TradeBotData.State tradeState = TradeBotData.State.valueOf(tradeStateValue);
+				if (tradeState == null)
+					throw new DataException("Illegal trade-bot trade-state fetched from repository");
+
+				byte[] secret = resultSet.getBytes(3);
+				String atAddress = resultSet.getString(4);
+				byte[] lastTransactionSignature = resultSet.getBytes(5);
+
+				TradeBotData tradeBotData = new TradeBotData(tradePrivateKey, tradeState, secret, atAddress, lastTransactionSignature);
+				allTradeBotData.add(tradeBotData);
+			} while (resultSet.next());
+
+			return allTradeBotData;
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch trade-bot trading states from repository", e);
+		}
+	}
+
+}

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

@@ -618,6 +618,13 @@ public class HSQLDBDatabaseUpdates {
 					stmt.execute("CREATE TABLE PublicizeTransactions (signature Signature, nonce INT NOT NULL, " + TRANSACTION_KEYS + ")");
 					break;
 
+				case 20:
+					// Trade bot
+					stmt.execute("CREATE TABLE TradeBotStates (trade_private_key QortalPrivateKey NOT NULL, trade_state TINYINT NOT NULL, "
+							+ "secret VARBINARY(32) NOT NULL, at_address QortalAddress, "
+							+ "last_transaction_signature Signature, PRIMARY KEY (trade_private_key)");
+					break;
+
 				default:
 					// nothing to do
 					return false;

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

@@ -32,6 +32,7 @@ import org.qortal.repository.ArbitraryRepository;
 import org.qortal.repository.AssetRepository;
 import org.qortal.repository.BlockRepository;
 import org.qortal.repository.ChatRepository;
+import org.qortal.repository.CrossChainRepository;
 import org.qortal.repository.DataException;
 import org.qortal.repository.GroupRepository;
 import org.qortal.repository.NameRepository;
@@ -115,6 +116,11 @@ public class HSQLDBRepository implements Repository {
 		return new HSQLDBChatRepository(this);
 	}
 
+	@Override
+	public CrossChainRepository getCrossChainRepository() {
+		return new HSQLDBCrossChainRepository(this);
+	}
+
 	@Override
 	public GroupRepository getGroupRepository() {
 		return new HSQLDBGroupRepository(this);