More work on CHAT API / support.

Renamed GET /chats/search to /chats/messages.

Added GET /chats/active/{address} to return lists of group chats
and direct chats involving {address}, where a chat message exists.

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

@@ -15,6 +15,7 @@ import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.GET;
 import javax.ws.rs.POST;
 import javax.ws.rs.Path;
+import javax.ws.rs.PathParam;
 import javax.ws.rs.QueryParam;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -24,6 +25,7 @@ import org.qortal.api.ApiErrors;
 import org.qortal.api.ApiExceptionFactory;
 import org.qortal.api.Security;
 import org.qortal.crypto.Crypto;
+import org.qortal.data.chat.ActiveChats;
 import org.qortal.data.chat.ChatMessage;
 import org.qortal.data.transaction.ChatTransactionData;
 import org.qortal.data.transaction.TransactionData;
@@ -49,7 +51,7 @@ public class ChatResource {
 	HttpServletRequest request;
 
 	@GET
-	@Path("/search")
+	@Path("/messages")
 	@Operation(
 		summary = "Find chat messages",
 		description = "Returns CHAT messages that match criteria. Must provide EITHER 'txGroupId' OR two 'involving' addresses.",
@@ -100,6 +102,34 @@ public class ChatResource {
 		}
 	}
 
+	@GET
+	@Path("/active/{address}")
+	@Operation(
+		summary = "Find active chats (group/direct) involving address",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					array = @ArraySchema(
+						schema = @Schema(
+							implementation = ActiveChats.class
+						)
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public ActiveChats getActiveChats(@PathParam("address") String address) {
+		if (address == null || !Crypto.isValidAddress(address))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			return repository.getChatRepository().getActiveChats(address);
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@POST
 	@Operation(
 		summary = "Build raw, unsigned, CHAT transaction",

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

@@ -0,0 +1,95 @@
+package org.qortal.data.chat;
+
+import java.util.List;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+
+@XmlAccessorType(XmlAccessType.FIELD)
+public class ActiveChats {
+
+	@XmlAccessorType(XmlAccessType.FIELD)
+	public static class GroupChat {
+		private int groupId;
+		private String groupName;
+		private long timestamp;
+
+		protected GroupChat() {
+			/* JAXB */
+		}
+
+		public GroupChat(int groupId, String groupName, long timestamp) {
+			this.groupId = groupId;
+			this.groupName = groupName;
+			this.timestamp = timestamp;
+		}
+
+		public int getGroupId() {
+			return this.groupId;
+		}
+
+		public String getGroupName() {
+			return this.groupName;
+		}
+
+		public long getTimestamp() {
+			return this.timestamp;
+		}
+	}
+
+	@XmlAccessorType(XmlAccessType.FIELD)
+	public static class DirectChat {
+		private String address;
+		private String name;
+		private long timestamp;
+
+		protected DirectChat() {
+			/* JAXB */
+		}
+
+		public DirectChat(String address, String name, long timestamp) {
+			this.address = address;
+			this.name = name;
+			this.timestamp = timestamp;
+		}
+
+		public String getAddress() {
+			return this.address;
+		}
+
+		public String getName() {
+			return this.name;
+		}
+
+		public long getTimestamp() {
+			return this.timestamp;
+		}
+	}
+
+	// Properties
+
+	private List<GroupChat> groups;
+
+	private List<DirectChat> direct;
+
+	// Constructors
+
+	protected ActiveChats() {
+		/* For JAXB */
+	}
+
+	// For repository use
+	public ActiveChats(List<GroupChat> groups, List<DirectChat> direct) {
+		this.groups = groups;
+		this.direct = direct;
+	}
+
+	public List<GroupChat> getGroups() {
+		return this.groups;
+	}
+
+	public List<DirectChat> getDirect() {
+		return this.direct;
+	}
+
+}

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

@@ -17,15 +17,9 @@ public class ChatMessage {
 	/* Address of sender */
 	private String sender;
 
-	/* Registered name of sender (if any) */
-	private String senderName; // can be null
-
 	/* Address of recipient (if any) */
 	private String recipient; // can be null
 
-	/* Registered name of recipient (if any) */
-	private String recipientName; // can be null
-
 	private byte[] data;
 
 	private boolean isText;
@@ -38,15 +32,13 @@ public class ChatMessage {
 	}
 
 	// For repository use
-	public ChatMessage(long timestamp, int txGroupId, byte[] senderPublicKey, String sender, String senderName,
-			String recipient, String recipientName, byte[] data, boolean isText, boolean isEncrypted) {
+	public ChatMessage(long timestamp, int txGroupId, byte[] senderPublicKey, String sender,
+			String recipient, byte[] data, boolean isText, boolean isEncrypted) {
 		this.timestamp = timestamp;
 		this.txGroupId = txGroupId;
 		this.senderPublicKey = senderPublicKey;
 		this.sender = sender;
-		this.senderName = senderName;
 		this.recipient = recipient;
-		this.recipientName = recipientName;
 		this.data = data;
 		this.isText = isText;
 		this.isEncrypted = isEncrypted;
@@ -68,18 +60,10 @@ public class ChatMessage {
 		return this.sender;
 	}
 
-	public String getSenderName() {
-		return this.senderName;
-	}
-
 	public String getRecipient() {
 		return this.recipient;
 	}
 
-	public String getRecipientName() {
-		return this.recipientName;
-	}
-
 	public byte[] getData() {
 		return this.data;
 	}

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

@@ -2,6 +2,7 @@ package org.qortal.repository;
 
 import java.util.List;
 
+import org.qortal.data.chat.ActiveChats;
 import org.qortal.data.chat.ChatMessage;
 
 public interface ChatRepository {
@@ -15,4 +16,6 @@ public interface ChatRepository {
 			Integer txGroupId, List<String> involving,
 			Integer limit, Integer offset, Boolean reverse) throws DataException;
 
+	public ActiveChats getActiveChats(String address) throws DataException;
+
 }

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

@@ -5,9 +5,13 @@ import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;
 
+import org.qortal.data.chat.ActiveChats;
+import org.qortal.data.chat.ActiveChats.DirectChat;
+import org.qortal.data.chat.ActiveChats.GroupChat;
 import org.qortal.data.chat.ChatMessage;
 import org.qortal.repository.ChatRepository;
 import org.qortal.repository.DataException;
+import org.qortal.transaction.Transaction.TransactionType;
 
 public class HSQLDBChatRepository implements ChatRepository {
 
@@ -28,12 +32,9 @@ public class HSQLDBChatRepository implements ChatRepository {
 
 		StringBuilder sql = new StringBuilder(1024);
 
-		sql.append("SELECT created_when, tx_group_id, creator, sender, SenderNames.name, "
-				+ "recipient, RecipientNames.name, data, is_text, is_encrypted "
+		sql.append("SELECT created_when, tx_group_id, creator, sender, recipient, data, is_text, is_encrypted "
 				+ "FROM ChatTransactions "
-				+ "JOIN Transactions USING (signature) "
-				+ "LEFT OUTER JOIN Names AS SenderNames ON SenderNames.owner = sender "
-				+ "LEFT OUTER JOIN Names AS RecipientNames ON RecipientNames.owner = recipient ");
+				+ "JOIN Transactions USING (signature) ");
 
 		// WHERE clauses
 
@@ -88,15 +89,13 @@ public class HSQLDBChatRepository implements ChatRepository {
 				int groupId = resultSet.getInt(2);
 				byte[] senderPublicKey = resultSet.getBytes(3);
 				String sender = resultSet.getString(4);
-				String senderName = resultSet.getString(5);
-				String recipient = resultSet.getString(6);
-				String recipientName = resultSet.getString(7);
-				byte[] data = resultSet.getBytes(8);
-				boolean isText = resultSet.getBoolean(9);
-				boolean isEncrypted = resultSet.getBoolean(10);
+				String recipient = resultSet.getString(5);
+				byte[] data = resultSet.getBytes(6);
+				boolean isText = resultSet.getBoolean(7);
+				boolean isEncrypted = resultSet.getBoolean(8);
 
 				ChatMessage chatMessage = new ChatMessage(timestamp, groupId, senderPublicKey, sender,
-						senderName, recipient, recipientName, data, isText, isEncrypted);
+						recipient, data, isText, isEncrypted);
 
 				chatMessages.add(chatMessage);
 			} while (resultSet.next());
@@ -107,4 +106,88 @@ public class HSQLDBChatRepository implements ChatRepository {
 		}
 	}
 
+	@Override
+	public ActiveChats getActiveChats(String address) throws DataException {
+		List<GroupChat> groupChats = getActiveGroupChats(address);
+		List<DirectChat> directChats = getActiveDirectChats(address);
+
+		return new ActiveChats(groupChats, directChats);
+	}
+
+	private List<GroupChat> getActiveGroupChats(String address) throws DataException {
+		// Find groups where address is a member and there is a chat
+		String groupsSql = "SELECT group_id, group_name, latest_timestamp "
+				+ "FROM GroupMembers "
+				+ "JOIN Groups USING (group_id) "
+				+ "CROSS JOIN LATERAL("
+					+ "SELECT created_when "
+					+ "FROM Transactions "
+					+ "WHERE tx_group_id = Groups.group_id AND type = " + TransactionType.CHAT.value + " "
+					+ "ORDER BY created_when DESC "
+					+ "LIMIT 1"
+				+ ") AS LatestMessages (latest_timestamp) "
+				+ "WHERE address = ?";
+
+		List<GroupChat> groupChats = new ArrayList<>();
+		try (ResultSet resultSet = this.repository.checkedExecute(groupsSql, address)) {
+			if (resultSet == null)
+				return groupChats;
+
+			do {
+				int groupId = resultSet.getInt(1);
+				String groupName = resultSet.getString(2);
+				long timestamp = resultSet.getLong(3);
+
+				GroupChat groupChat = new GroupChat(groupId, groupName, timestamp);
+				groupChats.add(groupChat);
+			} while (resultSet.next());
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch active group chats from repository", e);
+		}
+
+		return groupChats;
+	}
+
+	private List<DirectChat> getActiveDirectChats(String address) throws DataException {
+		// Find chat messages involving address
+		String directSql = "SELECT other_address, name, latest_timestamp "
+				+ "FROM ("
+					+ "SELECT recipient FROM ChatTransactions "
+					+ "WHERE sender = ? AND recipient IS NOT NULL "
+					+ "UNION "
+					+ "SELECT sender FROM ChatTransactions "
+					+ "WHERE recipient = ?"
+				+ ") AS OtherParties (other_address) "
+				+ "CROSS JOIN LATERAL("
+					+ "SELECT created_when FROM ChatTransactions "
+					+ "NATURAL JOIN Transactions "
+					+ "WHERE (sender = other_address AND recipient = ?) "
+					+ "OR (sender = ? AND recipient = other_address) "
+					+ "ORDER BY created_when DESC "
+					+ "LIMIT 1"
+				+ ") AS LatestMessages (latest_timestamp) "
+				+ "LEFT OUTER JOIN Names ON owner = other_address";
+
+		Object[] bindParams = new Object[] { address, address, address, address };
+
+		List<DirectChat> directChats = new ArrayList<>();
+		try (ResultSet resultSet = this.repository.checkedExecute(directSql, bindParams)) {
+			if (resultSet == null)
+				return directChats;
+
+			do {
+				String otherAddress = resultSet.getString(1);
+				String name = resultSet.getString(2);
+				long timestamp = resultSet.getLong(3);
+
+				DirectChat directChat = new DirectChat(otherAddress, name, timestamp);
+				directChats.add(directChat);
+			} while (resultSet.next());
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch active direct chats from repository", e);
+		}
+
+		return directChats;
+	}
+
 }