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

@@ -2,70 +2,160 @@ 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 String username;
+    private Socket socket;
+    private UserManager userManager;
+    private ObjectInputStream in;
+    private ObjectOutputStream out;
 
     public ClientSession(Socket socket, UserManager userManager) {
-        // TODO : Create an ObjectOutputStream from socket.getOutputStream()
-        //         and an ObjectInputStream from socket.getInputStream().
+        try {
+            this.socket = socket;
+            this.userManager = userManager;
+
+            out = new ObjectOutputStream(socket.getOutputStream());
+            in = new ObjectInputStream(socket.getInputStream());
+
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
     }
 
     @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 loginMessage)) {
+                socket.close();
+                return;
+            }
 
-            // 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 (loginMessage.getType() != MessageType.LOGIN) {
+                socket.close();
+                return;
+            }
+
+            username = loginMessage.getSender();
+
+            boolean added = userManager.addUser(username, this);
+
+            if (!added) {
+                ChatMessage failedMessage = new ChatMessage(
+                        MessageType.LOGIN_FAILED,
+                        "SERVER",
+                        username,
+                        "Username already exists"
+                );
+
+                send(failedMessage);
+                socket.close();
+                return;
+            }
+
+            FileManager.createUserFolders(username);
+
+            ChatMessage successMessage = new ChatMessage(
+                    MessageType.LOGIN_SUCCESS,
+                    "SERVER",
+                    username,
+                    "Login successful"
+            );
+
+            send(successMessage);
+
+            while (true) {
+                Object object = in.readObject();
+
+                if (object instanceof ChatMessage msg) {
+                    handleChatMessage(msg);
+                }
+
+                if (object instanceof FileMessage fileMsg) {
+                    handleFileMessage(fileMsg);
+                }
+            }
 
         } 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) {
+                userManager.removeUser(username);
+            }
         }
     }
 
-
     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.send(msg);
+                }
             }
+
             case PRIVATE_MESSAGE -> {
-                // TODO: Forward this message to the receiver user.
+                ClientSession receiver = userManager.getUser(msg.getReceiver());
+
+                if (receiver != null) {
+                    receiver.send(msg);
+                }
             }
+
             case USER_LIST -> {
-                // TODO: Reply to the requester with the list of online users.
+                ChatMessage userListMessage = new ChatMessage(
+                        MessageType.USER_LIST,
+                        "SERVER",
+                        username,
+                        userManager.listUsers()
+                );
+
+                send(userListMessage);
+            }
+
+            default -> {
             }
         }
     }
 
     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());
+        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 receiver = userManager.getUser(fileMsg.getReceiver());
+
+        if (receiver != null) {
+            receiver.send(fileMsg);
+        }
+    }
+
+    public void send(ChatMessage msg) throws IOException {
+        out.writeObject(msg);
+        out.flush();
+    }
+
+    public void send(FileMessage msg) throws IOException {
+        out.writeObject(msg);
+        out.flush();
     }
 }