Send pending messages after successful handshake

Instead of caching pending messages during the handshake and relaying
them afterwards, they are now sent after the handshake has been
completed.

This is possible because the relevant processors (messages and status
changes) are now event handlers which are registered at the event bus,
which means that they can immediately react to pending messages even if
Client#initReceiver has not been fully executed yet.

Because Client#initReceiver exists for that very reason, it is now
longer necessary. ID generator initialization, which was its other part,
is now directly handled in Startup#performHandshake, which is a far more
sensible placement.

Fixes #106

client/src/main/java/envoy/client/net/Client.java

@@ -12,7 +12,7 @@ import envoy.data.*;
 import envoy.event.*;
 import envoy.util.*;
 
-import envoy.client.data.*;
+import envoy.client.data.ClientConfig;
 import envoy.client.event.EnvoyCloseEvent;
 
 /**
@@ -55,13 +55,12 @@ public final class Client implements EventListener, Closeable {
 	 * the handshake does exceed this time limit, an exception is thrown.
 	 *
 	 * @param credentials the login credentials of the user
-	 * @param cacheMap    the map of all caches needed
 	 * @throws TimeoutException     if the server could not be reached
 	 * @throws IOException          if the login credentials could not be written
 	 * @throws InterruptedException if the current thread is interrupted while waiting for the
 	 *                              handshake response
 	 */
-	public void performHandshake(LoginCredentials credentials, CacheMap cacheMap)
+	public void performHandshake(LoginCredentials credentials)
 		throws TimeoutException, IOException, InterruptedException {
 		if (online)
 			throw new IllegalStateException("Handshake has already been performed successfully");
@@ -79,7 +78,6 @@ public final class Client implements EventListener, Closeable {
 		// Register user creation processor, contact list processor, message cache and
 		// authentication token
 		receiver.registerProcessor(User.class, sender -> this.sender = sender);
-		receiver.registerProcessors(cacheMap.getMap());
 
 		// Start receiver
 		receiver.start();
@@ -101,42 +99,18 @@ public final class Client implements EventListener, Closeable {
 
 			if (System.currentTimeMillis() - start > 5000) {
 				rejected = true;
+				socket.close();
+				receiver.removeAllProcessors();
 				throw new TimeoutException("Did not log in after 5 seconds");
 			}
 			Thread.sleep(500);
 		}
 
-		online = true;
+		// Remove handshake specific processors
-		logger.log(Level.INFO, "Handshake completed.");
-	}
-
-	/**
-	 * Initializes the {@link Receiver} used to process data sent from the server to this client.
-	 *
-	 * @param localDB  the local database used to persist the current {@link IDGenerator}
-	 * @param cacheMap the map of all caches needed
-	 * @throws IOException if no {@link IDGenerator} is present and none could be requested from the
-	 *                     server
-	 * @since Envoy Client v0.2-alpha
-	 */
-	public void initReceiver(LocalDB localDB, CacheMap cacheMap) throws IOException {
-		checkOnline();
-
-		// Remove all processors as they are only used during the handshake
 		receiver.removeAllProcessors();
 
-		// Relay cached messages and message status changes
+		online = true;
-		cacheMap.get(Message.class).setProcessor(eventBus::dispatch);
+		logger.log(Level.INFO, "Handshake completed.");
-		cacheMap.get(GroupMessage.class).setProcessor(eventBus::dispatch);
-		cacheMap.get(MessageStatusChange.class).setProcessor(eventBus::dispatch);
-		cacheMap.get(GroupMessageStatusChange.class).setProcessor(eventBus::dispatch);
-
-		// Request a generator if none is present or the existing one is consumed
-		if (!localDB.hasIDGenerator() || !localDB.getIDGenerator().hasNext())
-			requestIDGenerator();
-
-		// Relay caches
-		cacheMap.getMap().values().forEach(Cache::relay);
 	}
 
 	/**

client/src/main/java/envoy/client/ui/Startup.java

@@ -12,7 +12,7 @@ import javafx.stage.Stage;
 
 import envoy.data.*;
 import envoy.data.User.UserStatus;
-import envoy.event.*;
+import envoy.event.UserStatusChange;
 import envoy.exception.EnvoyException;
 import envoy.util.EnvoyLog;
 
@@ -115,21 +115,20 @@ public final class Startup extends Application {
 	 * @since Envoy Client v0.2-beta
 	 */
 	public static boolean performHandshake(LoginCredentials credentials) {
-		final var cacheMap = new CacheMap();
-		cacheMap.put(Message.class, new Cache<Message>());
-		cacheMap.put(GroupMessage.class, new Cache<GroupMessage>());
-		cacheMap.put(MessageStatusChange.class, new Cache<MessageStatusChange>());
-		cacheMap.put(GroupMessageStatusChange.class, new Cache<GroupMessageStatusChange>());
 		final var originalStatus =
 			localDB.getUser() == null ? UserStatus.ONLINE : localDB.getUser().getStatus();
 		try {
-			client.performHandshake(credentials, cacheMap);
+			client.performHandshake(credentials);
 			if (client.isOnline()) {
 
 				// Restore the original status as the server automatically returns status ONLINE
 				client.getSender().setStatus(originalStatus);
 				loadChatScene();
-				client.initReceiver(localDB, cacheMap);
+
+				// Request an ID generator if none is present or the existing one is consumed
+				if (!localDB.hasIDGenerator() || !localDB.getIDGenerator().hasNext())
+					client.requestIDGenerator();
+
 				return true;
 			} else
 				return false;

server/src/main/java/envoy/server/processors/LoginCredentialProcessor.java

@@ -40,6 +40,7 @@ public final class LoginCredentialProcessor implements ObjectProcessor<LoginCred
 		// Cache this write proxy for user-independent notifications
 		UserStatusChangeProcessor.setWriteProxy(writeProxy);
 
+		// Check for compatible versions
 		if (!VersionUtil.verifyCompatibility(credentials.getClientVersion())) {
 			logger.info("The client has the wrong version.");
 			writeProxy.write(socketID, new HandshakeRejection(WRONG_VERSION));
@@ -70,10 +71,10 @@ public final class LoginCredentialProcessor implements ObjectProcessor<LoginCred
 						writeProxy.write(socketID, new HandshakeRejection(INVALID_TOKEN));
 						return;
 					}
-				} else
+				} else if (!PasswordUtil.validate(credentials.getPassword(),
+					user.getPasswordHash())) {
 
 					// Check the password hash
-				if (!PasswordUtil.validate(credentials.getPassword(), user.getPasswordHash())) {
 					logger.info(user + " has entered the wrong password.");
 					writeProxy.write(socketID, new HandshakeRejection(WRONG_PASSWORD_OR_USER));
 					return;
@@ -101,7 +102,8 @@ public final class LoginCredentialProcessor implements ObjectProcessor<LoginCred
 				writeProxy.write(socketID, new HandshakeRejection(USERNAME_TAKEN));
 				return;
 			} catch (final NoResultException e) {
-				// Creation of a new user
+
+				// Create a new user
 				user = new User();
 				user.setName(credentials.getIdentifier());
 				user.setLastSeen(Instant.now());
@@ -138,6 +140,15 @@ public final class LoginCredentialProcessor implements ObjectProcessor<LoginCred
 			persistenceManager.updateContact(user);
 			writeProxy.write(socketID, new NewAuthToken(token));
 		}
+
+		// Notify the user if a contact deletion has happened since he last logged in
+		if (user.getLatestContactDeletion().isAfter(user.getLastSeen()))
+			writeProxy.write(socketID, new ContactsChangedSinceLastLogin());
+
+		// Complete the handshake
+		writeProxy.write(socketID, user.toCommon());
+
+		// Send pending (group) messages and status changes
 		final var pendingMessages =
 			PersistenceManager.getInstance().getPendingMessages(user, credentials.getLastSync());
 		pendingMessages.removeIf(GroupMessage.class::isInstance);
@@ -162,9 +173,10 @@ public final class LoginCredentialProcessor implements ObjectProcessor<LoginCred
 					writeProxy.write(connectionManager.getSocketID(msg.getSender().getID()),
 						new MessageStatusChange(msgCommon));
 				}
-			} else
+			} else {
 				writeProxy.write(socketID, new MessageStatusChange(msgCommon));
 			}
+		}
 
 		final List<GroupMessage> pendingGroupMessages = PersistenceManager.getInstance()
 			.getPendingGroupMessages(user, credentials.getLastSync());
@@ -197,10 +209,11 @@ public final class LoginCredentialProcessor implements ObjectProcessor<LoginCred
 					}
 
 					PersistenceManager.getInstance().updateMessage(gmsg);
-				} else
+				} else {
 
 					// Just send the message without updating if it was received in the past
 					writeProxy.write(socketID, gmsgCommon);
+				}
 			} else {
 
 				// Sending group message status changes
@@ -220,11 +233,5 @@ public final class LoginCredentialProcessor implements ObjectProcessor<LoginCred
 					writeProxy.write(socketID, new MessageStatusChange(gmsgCommon));
 			}
 		}
-		// Notify the user if a contact deletion has happened since he last logged in
-		if (user.getLatestContactDeletion().isAfter(user.getLastSeen()))
-			writeProxy.write(socketID, new ContactsChangedSinceLastLogin());
-
-		// Complete the handshake
-		writeProxy.write(socketID, user.toCommon());
 	}
 }