Edit logout logic

src/main/java/org/to/telegramfinalproject/Client/ActionHandler.java

@@ -177,9 +177,9 @@ public class ActionHandler {
                     break;
 
                 case "3":
-                    Session.currentUser = null;
-                    Session.chatList = null;
-                    System.out.println("Logged out.");
+
+                    logout();
+
                     return;
                 default:
                     System.out.println("Invalid choice.");
@@ -225,5 +225,21 @@ public class ActionHandler {
         send(request);
     }
 
+
+
+    public void logout() {
+        if (Session.currentUser != null && Session.currentUser.has("user_id")) {
+            JSONObject request = new JSONObject();
+            String userId = Session.currentUser.getString("internalUUID");
+            request.put("action", "logout");
+            request.put("user_id",userId);
+            send(request);
+            Session.currentUser = null;
+            Session.chatList = null;
+        } else {
+            System.out.println("Not logged in.");
+        }
+    }
+
 }
 

src/main/java/org/to/telegramfinalproject/Client/TelegramClient.java

@@ -1,5 +1,7 @@
 package org.to.telegramfinalproject.Client;
 
+import org.json.JSONObject;
+
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
@@ -56,27 +58,32 @@ public class TelegramClient {
                     }
                     break;
                 case "3":
-                    System.out.println(" Disconnecting...");
+                    System.out.println("Disconnecting...");
+
+                    if (Session.currentUser != null && Session.currentUser.has("internalUUID")) {
+                        try {
+                            JSONObject logoutRequest = new JSONObject();
+                            logoutRequest.put("action", "logout");
+                            logoutRequest.put("user_id", Session.currentUser.getString("internalUUID"));
+                            out.println(logoutRequest.toString());
+                            in.readLine();
+                        } catch (Exception e) {
+                            System.err.println("Failed to notify server on logout: " + e.getMessage());
+                        }
+                    }
 
                     try {
-                        if (this.socket != null) {
-                            this.socket.close();
-                        }
-
-                        if (this.in != null) {
-                            this.in.close();
-                        }
-
-                        if (this.out != null) {
-                            this.out.close();
-                        }
-
+                        if (socket != null) socket.close();
+                        if (in != null) in.close();
+                        if (out != null) out.close();
                         System.out.println("Disconnected.");
                     } catch (IOException e) {
-                        System.err.println(" Error closing connection: " + e.getMessage());
+                        System.err.println("Error closing connection: " + e.getMessage());
                     }
 
                     return;
+
+
                 default:
                     System.out.println("Invalid choice. Please try again.");
             }

src/main/java/org/to/telegramfinalproject/Server/ClientHandler.java

@@ -69,12 +69,20 @@ public class ClientHandler implements Runnable {
                         } else {
 
                             User user = authService.login(request.getUsername(), request.getPassword());
-                            if (user == null) {
+
+                            if (user == null){
                                 response = new ResponseModel("error", "Login failed.");
                                 break;
                             }
                             this.currentUser = user;
 
+                            if (SessionManager.contains(user.getInternal_uuid())) {
+                                response = new ResponseModel("error", "You are already logged in from another device.");
+                                break;
+
+                            }
+
+
                             SessionManager.addUser(user.getInternal_uuid(), this.socket);
                             userDatabase.updateUserStatus(user.getInternal_uuid(), "online");
                             List<Contact> contacts = ContactDatabase.getContacts(user.getInternal_uuid());
@@ -118,16 +126,21 @@ public class ClientHandler implements Runnable {
 
                     case "logout": {
                         String user_Id = requestJson.optString("user_id");
-                        if (userId != null && !user_Id.isEmpty()) {
-                            UUID uuid = UUID.fromString(user_Id);
-                            userDatabase.updateUserStatus(uuid, "offline");
-                            userDatabase.updateLastSeen(uuid);
-                            SessionManager.removeUser(uuid);
-                            response = new ResponseModel("success", "Logged out.");
+                        if (user_Id != null && !user_Id.isEmpty()) {
+                            try {
+                                UUID uuid = UUID.fromString(user_Id);
+                                userDatabase.updateUserStatus(uuid, "offline");
+                                userDatabase.updateLastSeen(uuid);
+                                SessionManager.removeUser(uuid);
+                                response = new ResponseModel("success", "Logged out.");
+                            } catch (IllegalArgumentException ex) {
+                                response = new ResponseModel("error", "Invalid UUID format for user_id.");
+                            }
                         } else {
                             response = new ResponseModel("error", "Invalid user_id for logout.");
                         }
                         break;
+
                     }
 
                     case "search": {

src/main/java/org/to/telegramfinalproject/Server/SessionManager.java

@@ -32,4 +32,12 @@ public class SessionManager {
         }
         return null;
     }
+
+    public static boolean contains(UUID userId) {
+        return onlineUsers.containsKey(userId);
+    }
+
+
+
+
 }