Fix message duplication with multiple users

src/main/java/fr/insa/clavardator/chat/ChatHistory.java

@@ -3,12 +3,10 @@ package fr.insa.clavardator.chat;
 import fr.insa.clavardator.db.DatabaseController;
 import fr.insa.clavardator.users.CurrentUser;
 import fr.insa.clavardator.users.PeerUser;
+import fr.insa.clavardator.util.Log;
 import javafx.application.Platform;
 
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.Timer;
-import java.util.TimerTask;
+import java.util.*;
 
 public class ChatHistory {
 	private final DatabaseController db;
@@ -28,10 +26,18 @@ public class ChatHistory {
 		historyListener.add(listener);
 	}
 
+	public void removeHistoryLoadedListener(HistoryLoadedCallback listener) {
+		historyListener.remove(listener);
+	}
+
 	public void addMessageAddedListener(MessageAddedCallback listener) {
 		messageListener.add(listener);
 	}
 
+	public void removeMessageAddedListener(MessageAddedCallback listener) {
+		messageListener.remove(listener);
+	}
+
 	private void notifyHistoryLoaded() {
 		historyListener.forEach(l -> l.onHistoryLoaded(user, history));
 	}

src/main/java/fr/insa/clavardator/ui/chat/ChatController.java

@@ -46,32 +46,38 @@ public class ChatController implements Initializable {
 	}
 
 	public void setRemoteUser(PeerUser remoteUser) {
-		this.remoteUser = remoteUser;
 		this.chatFooterController.setRemoteUser(remoteUser);
 		this.chatHeaderController.setRemoteUser(remoteUser);
 		setState(State.LOADING);
 
+		if (this.remoteUser != null) {
+			final ChatHistory oldHistory = this.remoteUser.getHistory();
+			oldHistory.removeHistoryLoadedListener(onHistoryLoaded);
+			oldHistory.removeMessageAddedListener(onMessageAdded);
+		}
+
 		final ChatHistory history = remoteUser.getHistory();
-		history.addHistoryLoadedListener(this::onHistoryLoaded);
-		history.addMessageAddedListener(this::onMessageAdded);
+		history.addHistoryLoadedListener(onHistoryLoaded);
+		history.addMessageAddedListener(onMessageAdded);
 		history.load();
+		this.remoteUser = remoteUser;
 	}
 
-	private void onHistoryLoaded(PeerUser user, ArrayList<Message> messages) {
+	private final ChatHistory.HistoryLoadedCallback onHistoryLoaded = (PeerUser user, ArrayList<Message> messages) -> {
 		if (user.equals(remoteUser)) {
 			messageList.setItems(FXCollections.observableArrayList(messages));
 			messageList.scrollTo(messageList.getItems().size() - 1);
 			setState(State.DONE);
 		}
-	}
+	};
 
-	private void onMessageAdded(PeerUser user, Message message) {
+	private final ChatHistory.MessageAddedCallback onMessageAdded = (PeerUser user, Message message) -> {
 		Log.v(this.getClass().getSimpleName(), "Message added: " + message.getText());
 		Platform.runLater(() -> {
 			messageList.getItems().add(message);
 			messageList.scrollTo(messageList.getItems().size() - 1);
 		});
-	}
+	};
 
 	private void setState(State state) {
 		switch (state) {