Assignment-10

src/main/java/com/university/chat/Server/ClientSession.java

@@ -2,70 +2,127 @@ package com.university.chat.Server;
 
 import com.university.chat.Common.ChatMessage;
 import com.university.chat.Common.FileMessage;
+import com.university.chat.Common.MessageType;
 
 import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
 import java.net.Socket;
 import java.nio.file.Files;
 
 public class ClientSession implements Runnable {
-
+    private final Socket socket;
+    private final UserManager userManager;
+    private ObjectOutputStream out;
+    private ObjectInputStream in;
     private String username;
 
     public ClientSession(Socket socket, UserManager userManager) {
-        // TODO : Create an ObjectOutputStream from socket.getOutputStream()
-        //         and an ObjectInputStream from socket.getInputStream().
+        this.socket = socket;
+        this.userManager = userManager;
+
+        try {
+            this.out = new ObjectOutputStream(socket.getOutputStream());
+            this.out.flush();
+            this.in = new ObjectInputStream(socket.getInputStream());
+        } catch (IOException e) {
+            System.err.println("Error initializing streams for session: " + e.getMessage());
+        }
     }
 
     @Override
     public void run() {
         try {
+            Object firstObject = in.readObject();
 
-            // TODO: Welcome the user (login step)
-            //  1. Read the first object sent by the client.
-            //  2. Check it's a ChatMessage with type LOGIN.
-            //  3. Extract the username.
-            //  4. Try to register the user via userManager.addUser(...).
-            //  5. If the username is taken, send back LOGIN_FAILED and close the socket.
-            //  6. Otherwise, create the user's folders with FileManager.createUserFolders(...)
-            //      and send back LOGIN_SUCCESS.
+            if (firstObject instanceof ChatMessage loginMsg && loginMsg.getType() == MessageType.LOGIN) {
+                this.username = loginMsg.getSender();
 
-            // TODO: Main message loop
-            //   In a loop, call in.readObject(), you can separate messages by their type:
-            //     - if it's a ChatMessage      -> call handleChatMessage(msg)
-            //     - if it's a FileMessage      -> call handleFileMessage(fileMsg)
-            //   Keep looping until the connection is closed (an exception will be thrown).
+                if (userManager.addUser(username, this)) {
+                    FileManager.createUserFolders(username);
+                    sendMessage(new ChatMessage(MessageType.LOGIN_SUCCESS, "SERVER", username, "Login successful."));
+                    System.out.println("[Server] User logged in: " + username);
+                } else {
+                    sendMessage(new ChatMessage(MessageType.LOGIN_FAILED, "SERVER", username, "Username is already taken."));
+                    socket.close();
+                    return;
+                }
+            } else {
+                socket.close();
+                return;
+            }
 
+            while (true) {
+                Object receivedObject = in.readObject();
+
+                if (receivedObject instanceof ChatMessage) {
+                    handleChatMessage((ChatMessage) receivedObject);
+                } else if (receivedObject instanceof FileMessage) {
+                    handleFileMessage((FileMessage) receivedObject);
+                }
+            }
         } catch (Exception e) {
             System.out.println("Disconnected: " + username);
         } finally {
-            // TODO: Remove the user from UserManager so they no longer
-            //        receive broadcasts or appear in users list
+            if (username != null) {
+                if (userManager.getUser(username) == this) {
+                    userManager.removeUser(username);
+                    System.out.println("[Server] Safely removed active user: " + username);
+                }
+            }
+            try {
+                socket.close();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
         }
     }
 
-
     private void handleChatMessage(ChatMessage msg) throws IOException {
         switch (msg.getType()) {
             case PUBLIC_MESSAGE -> {
-                // TODO: Broadcast this message to every connected client.
+                for (ClientSession session : userManager.getAllSessions()) {
+                    session.sendMessage(msg);
+                }
             }
             case PRIVATE_MESSAGE -> {
-                // TODO: Forward this message to the receiver user.
+                ClientSession recipient = userManager.getUser(msg.getReceiver());
+                if (recipient != null) {
+                    recipient.sendMessage(msg);
+                } else {
+                    sendMessage(new ChatMessage(MessageType.PUBLIC_MESSAGE, "SERVER", username, "User " + msg.getReceiver() + " is offline."));
+                }
             }
             case USER_LIST -> {
-                // TODO: Reply to the requester with the list of online users.
+                String activeUsers = userManager.listUsers();
+                ChatMessage listMsg = new ChatMessage(MessageType.USER_LIST, "SERVER", username, activeUsers);
+                sendMessage(listMsg);
             }
+            default -> System.out.println("Unknown ChatMessage type received.");
         }
     }
 
     private void handleFileMessage(FileMessage fileMsg) throws IOException {
-        // Storing the file
         var sentPath = FileManager.getSentPath(fileMsg.getSender(), fileMsg.getFilename());
         var recvPath = FileManager.getReceivedPath(fileMsg.getReceiver(), fileMsg.getFilename());
 
         Files.write(sentPath, fileMsg.getData());
         Files.write(recvPath, fileMsg.getData());
 
-        // TODO: Forward the received file-message to the destination user.
+        ClientSession recipient = userManager.getUser(fileMsg.getReceiver());
+        if (recipient != null) {
+            recipient.sendMessage(fileMsg);
+        }
+    }
+
+    public synchronized void sendMessage(Object msg) {
+        try {
+            if (out != null) {
+                out.writeObject(msg);
+                out.flush();
+            }
+        } catch (IOException e) {
+            System.err.println("Failed to send packet to " + username + ": " + e.getMessage());
+        }
     }
 }