Work on download files(private chats and groups)

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

@@ -7,6 +7,9 @@ import org.to.telegramfinalproject.Models.ContactEntry;
 import org.to.telegramfinalproject.Models.SearchRequestModel;
 
 import java.io.*;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.time.LocalDateTime;
 import java.util.*;
 import java.util.concurrent.BlockingQueue;
@@ -23,19 +26,11 @@ public class ActionHandler {
 
 
 
-
-
     private void handleRealTime(JSONObject json) throws IOException {
         IncomingMessageListener listener = new IncomingMessageListener(this.in);
         listener.handleRealTimeEvent (json);
     }
-//    public ActionHandler(PrintWriter out, BufferedReader in, Scanner scanner) {
+
-//        this.out = out;
-//        this.in = in;
-//        this.scanner = scanner;
-//        ActionHandler.instance = this;
-//
-//    }
     public ActionHandler(PrintWriter out, BufferedReader in, DataOutputStream outBin, Scanner scanner) {
         this.out = out;
         this.in = in;
@@ -477,6 +472,12 @@ public class ActionHandler {
                 case "register":
                     Session.currentUser = response.getJSONObject("data");
 
+                    //for downloaded medias
+                    UUID accountId = UUID.fromString(Session.currentUser.getString("internal_uuid"));
+                    Session.downloadsIndex = new DownloadsIndex(accountId);
+
+
+
                     JSONArray chatListJson = Session.currentUser.getJSONArray("chat_list");
                     JSONArray Archived = Session.currentUser.getJSONArray("archived_chat_list");
                     JSONArray Active = Session.currentUser.getJSONArray("active_chat_list");
@@ -3648,6 +3649,18 @@ public class ActionHandler {
                     replyLabel = "↪️ Reply to " + repliedSender + ": \"" + repliedContent + "\"";
                 }
 
+                JSONArray atts = msg.optJSONArray("attachments");
+                if (atts != null && atts.length() > 0) {
+                    System.out.println("  📎 " + atts.length() + " attachment(s)");
+                    for (int a = 0; a < atts.length(); a++) {
+                        JSONObject att = atts.getJSONObject(a);
+                        String fn = att.optString("file_name", "(unnamed)");
+                        long sz = att.optLong("file_size", 0);
+                        System.out.printf("    - #%d %s (%s)\n", a + 1, fn, humanSize(sz));
+                    }
+                }
+
+
                 JSONArray reactions = msg.optJSONArray("reactions");
                 if (reactions != null && !reactions.isEmpty()) {
                     System.out.print(" 💬 Reactions: ");
@@ -3697,6 +3710,10 @@ public class ActionHandler {
                 boolean isSender = senderId.toString().equals(Session.currentUser.getString("internal_uuid"));
                 boolean isChannel = chat.getType().equals("channel");
                 boolean isOwnerOrAdmin = chat.isOwner() || chat.isAdmin();
+                //for media
+                JSONArray atts = selected.optJSONArray("attachments");
+                boolean hasAttachments = (atts != null && atts.length() > 0);
+
 
                 System.out.println("\n🎯 Selected message by " + selected.getString("sender_name"));
 
@@ -3722,6 +3739,9 @@ public class ActionHandler {
                         System.out.println("5. Delete");
                     }
                 }
+                if (hasAttachments) {
+                    System.out.println("D. Download attachment");
+                }
 
                 System.out.println("0. Back to message list");
                 System.out.print("➤ Select an action: ");
@@ -3754,6 +3774,15 @@ public class ActionHandler {
                             System.out.println("❌ You are not allowed to delete this message.");
                     }
                     case "0" -> {}
+
+                    case "D", "d" -> {
+                        if (hasAttachments) {
+                            downloadAttachmentFlow(chat, selected);
+                        } else {
+                            System.out.println("🚫 No attachments to download.");
+                        }
+                    }
+
                     default -> System.out.println("❌ Invalid option.");
                 }
 
@@ -3763,6 +3792,126 @@ public class ActionHandler {
         }
     }
 
+    private void downloadAttachmentFlow(ChatEntry chat, JSONObject msg) {
+        JSONArray atts = msg.optJSONArray("attachments");
+        if (atts == null || atts.length() == 0) {
+            System.out.println("🚫 No attachments.");
+            return;
+        }
+
+        int idx = 0;
+        if (atts.length() > 1) {
+            System.out.print("Which attachment [1.." + atts.length() + "]? ");
+            try {
+                String ans = scanner.nextLine().trim();
+                if (!ans.isEmpty()) {
+                    int n = Integer.parseInt(ans);
+                    if (n >= 1 && n <= atts.length()) idx = n - 1;
+                }
+            } catch (Exception ignored) { idx = 0; }
+        }
+
+        JSONObject att = atts.getJSONObject(idx);
+        String mediaKeyStr = att.optString("media_key", "");
+        if (mediaKeyStr.isBlank()) {
+            System.out.println("❌ Attachment missing media_key.");
+            return;
+        }
+
+        UUID mediaKey = UUID.fromString(mediaKeyStr);
+        String rawName = att.optString("file_name", mediaKey.toString());
+        String fileName = sanitizeFileName(rawName);
+        long declaredSize = att.optLong("file_size", 0L);
+
+        // ~/Downloads/TeleSock/<chatDisplayOrId or ChatUUID>/
+        String folderName = (chat.getDisplayId() != null && !chat.getDisplayId().isBlank())
+                ? chat.getDisplayId() : chat.getId().toString();
+        Path saveDir = Paths.get(System.getProperty("user.home"), "Downloads", "TeleSock", folderName);
+
+        try { Files.createDirectories(saveDir); } catch (IOException e) {
+            System.out.println("❌ Cannot create folder: " + saveDir + " -> " + e.getMessage());
+            return;
+        }
+
+        // اگر قبلاً دانلود شده (و فایل واقعاً وجود دارد)
+        try {
+            Path existing = Session.downloadsIndex.find(mediaKey);
+            if (existing != null) {
+                System.out.println("✅ Already downloaded: " + existing);
+                return;
+            }
+        } catch (IllegalStateException notInit) {
+            System.out.println("⚠️ DownloadsIndex not initialized. Call DownloadsIndex.init(<internal_uuid>) after login.");
+            // ادامه می‌دهیم؛ فقط کش نمی‌شود.
+        }
+
+        // جلوگیری از overwrite با انتخاب نام یکتا
+        Path target = uniquePath(saveDir, fileName);
+
+
+        // دانلود روی همان سوکت: Listener را موقتاً متوقف کن
+        TelegramClient.mediaBusy.set(true);
+        try {
+            Path saved = TelegramClient.getDownloader().download(mediaKey, saveDir, target.getFileName().toString());
+
+            long sizeToRecord = declaredSize > 0 ? declaredSize : Files.size(saved);
+            try {
+               Session.downloadsIndex.put(mediaKey, saved, sizeToRecord);
+            } catch (IllegalStateException notInit) {
+                // اگر init نشده بود، تنها کش نمی‌کنیم
+            }
+
+            System.out.println("✅ Saved to: " + saved + "  (" + humanSize(sizeToRecord) + ")");
+        } catch (Exception ex) {
+            System.out.println("❌ Download failed: " + ex.getMessage());
+        } finally {
+            TelegramClient.mediaBusy.set(false);
+        }
+    }
+
+    // نام یکتا اگر فایل موجود است: name.png -> name (1).png
+    private static Path uniquePath(Path dir, String fileName) {
+        Path p = dir.resolve(fileName);
+        if (!Files.exists(p)) return p;
+
+        String name = fileName;
+        String ext  = "";
+        int dot = fileName.lastIndexOf('.');
+        if (dot > 0 && dot < fileName.length()-1) {
+            name = fileName.substring(0, dot);
+            ext  = fileName.substring(dot); // includes dot
+        }
+        int i = 1;
+        while (true) {
+            Path cand = dir.resolve(String.format("%s (%d)%s", name, i, ext));
+            if (!Files.exists(cand)) return cand;
+            i++;
+        }
+    }
+
+    private static String sanitizeFileName(String s) {
+        // حذف مسیر و کاراکترهای غیرمجاز (برای ویندوز/یونیکس)
+        s = s.replace("\\", "/");
+        if (s.contains("/")) s = s.substring(s.lastIndexOf('/') + 1);
+        // کاراکترهای نامعتبر ویندوز: \ / : * ? " < > |
+        s = s.replaceAll("[\\\\/:*?\"<>|]", "_");
+        // جلوگیری از parent traversal
+        if (s.equals(".") || s.equals("..") || s.isBlank()) s = "file";
+        return s;
+    }
+
+    private static String humanSize(long b) {
+        if (b <= 0) return "0 B";
+        String[] u = {"B","KB","MB","GB","TB"};
+        int i = (int) Math.floor(Math.log(b) / Math.log(1024));
+        if (i < 0) i = 0;
+        if (i >= u.length) i = u.length - 1;
+        double v = b / Math.pow(1024, i);
+        return String.format("%.1f %s", v, u[i]);
+    }
+
+
+
     private void editMessage(UUID messageId) {
         System.out.print("📝 Enter new content: ");
         String newContent = scanner.nextLine().trim();
@@ -4130,6 +4279,39 @@ public class ActionHandler {
     }
 
 
+
+    private static String safeName(String s) {
+        if (s == null) return "unknown";
+        s = s.replace("\\", "/");
+        if (s.contains("/")) s = s.substring(s.lastIndexOf('/') + 1);
+        s = s.replaceAll("[\\\\/:*?\"<>|]", "_").trim();
+        if (s.isEmpty() || s.equals(".") || s.equals("..")) s = "unknown";
+        return s;
+    }
+
+    private static String accountFolderName() {
+        // اولویت: username → user_id → profile_name → internal_uuid
+        JSONObject me = Session.currentUser;
+        String acc = me.optString("username",
+                me.optString("user_id",
+                        me.optString("profile_name",
+                                me.optString("internal_uuid", "me"))));
+        return safeName(acc);
+    }
+
+    private static String chatFolderName(ChatEntry chat) {
+        // پرایوت: اسم طرف مقابل؛ گروه/کانال: اسم چت
+        String name = chat.getName();
+        if (name == null || name.isBlank()) {
+            // fallback به displayId یا id
+            name = chat.getDisplayId() != null && !chat.getDisplayId().isBlank()
+                    ? chat.getDisplayId()
+                    : String.valueOf(chat.getId());
+        }
+        return safeName(name);
+    }
+
+
 }
 
 

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

@@ -0,0 +1,30 @@
+// DownloadIndexRegistry.java
+package org.to.telegramfinalproject.Client;
+
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+
+public final class DownloadIndexRegistry {
+    private static final ConcurrentHashMap<UUID, DownloadsIndex> INSTANCES = new ConcurrentHashMap<>();
+    private static volatile boolean HOOK_REGISTERED = false;
+
+    private DownloadIndexRegistry() {}
+
+    public static DownloadsIndex forAccount(UUID accountId) {
+        registerHookOnce();
+        return INSTANCES.computeIfAbsent(accountId, DownloadsIndex::new);
+    }
+
+    public static void closeAccount(UUID accountId) {
+        DownloadsIndex idx = INSTANCES.remove(accountId);
+        if (idx != null) idx.saveQuietly();
+    }
+
+    private static synchronized void registerHookOnce() {
+        if (HOOK_REGISTERED) return;
+        Runtime.getRuntime().addShutdownHook(new Thread(() -> {
+            for (DownloadsIndex idx : INSTANCES.values()) idx.saveQuietly();
+        }));
+        HOOK_REGISTERED = true;
+    }
+}

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

@@ -0,0 +1,122 @@
+package org.to.telegramfinalproject.Client;
+
+import org.json.JSONObject;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.*;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+
+public final class DownloadsIndex {
+    private final UUID accountId;
+    private final Path indexFile;
+    private final Map<UUID, Entry> map = new ConcurrentHashMap<>();
+
+    public DownloadsIndex(UUID accountId) {
+        this.accountId = accountId;
+        this.indexFile = resolveIndexPath(accountId.toString());
+        load();
+    }
+
+
+    /** مسیر فایل ایندکس مخصوص هر اکانت */
+    private static Path resolveIndexPath(String accountId) {
+        String os = System.getProperty("os.name", "").toLowerCase();
+        String home = System.getProperty("user.home");
+
+        Path dir;
+        if (os.contains("win")) {
+            String appData = System.getenv("APPDATA");
+            dir = (appData != null)
+                    ? Paths.get(appData, "TeleSock")
+                    : Paths.get(home, "AppData", "Roaming", "TeleSock");
+        } else {
+            dir = Paths.get(home, ".telesock");
+        }
+        try { Files.createDirectories(dir); } catch (IOException ignored) {}
+        return dir.resolve("downloads-index-" + accountId + ".json");
+    }
+
+    /** لود از دیسک (اگر فایل وجود داشته باشد) */
+    private synchronized void load() {
+        map.clear();
+        try {
+            if (!Files.exists(indexFile)) return;
+            String json = Files.readString(indexFile, StandardCharsets.UTF_8);
+            if (json == null || json.isBlank()) return;
+
+            JSONObject root  = new JSONObject(json);
+            JSONObject items = root.optJSONObject("items");
+            if (items == null) return;
+
+            for (String key : items.keySet()) {
+                JSONObject e = items.getJSONObject(key);
+                map.put(UUID.fromString(key), new Entry(
+                        e.getString("path"),
+                        e.optLong("size", 0L),
+                        e.optLong("ts", System.currentTimeMillis())
+                ));
+            }
+        } catch (Exception e) {
+            System.err.println("⚠️ DownloadsIndex load failed: " + e.getMessage());
+        }
+    }
+
+    /** ذخیره اتمیک روی دیسک */
+    private synchronized void save() throws IOException {
+        JSONObject items = new JSONObject();
+        for (Map.Entry<UUID, Entry> it : map.entrySet()) {
+            JSONObject e = new JSONObject();
+            e.put("path", it.getValue().path);
+            e.put("size", it.getValue().size);
+            e.put("ts",   it.getValue().ts);
+            items.put(it.getKey().toString(), e);
+        }
+        byte[] data = new JSONObject().put("items", items).toString(2).getBytes(StandardCharsets.UTF_8);
+
+        Path tmp = indexFile.resolveSibling(indexFile.getFileName() + ".tmp");
+        Files.write(tmp, data);
+        try {
+            Files.move(tmp, indexFile, StandardCopyOption.REPLACE_EXISTING, StandardCopyOption.ATOMIC_MOVE);
+        } catch (AtomicMoveNotSupportedException ex) {
+            Files.move(tmp, indexFile, StandardCopyOption.REPLACE_EXISTING);
+        }
+    }
+
+    /** ذخیره‌ی بی‌سر‌وصدا */
+    public void saveQuietly() {
+        try { save(); } catch (Exception ignored) {}
+    }
+
+    /** اگر قبلاً دانلود شده و فایلش هست، مسیر را برمی‌گرداند؛ وگرنه رکورد کهنه پاک می‌شود. */
+    public Path find(UUID mediaKey) {
+        Entry e = map.get(mediaKey);
+        if (e == null) return null;
+        Path p = Paths.get(e.path);
+        if (Files.exists(p)) return p;
+        map.remove(mediaKey);
+        saveQuietly();
+        return null;
+    }
+
+    /** بعد از دانلود موفق */
+    public void put(UUID mediaKey, Path path, long size) {
+        map.put(mediaKey, new Entry(path.toString(), size, System.currentTimeMillis()));
+        saveQuietly();
+    }
+
+    /** اختیاری */
+    public void remove(UUID mediaKey) {
+        map.remove(mediaKey);
+        saveQuietly();
+    }
+
+    private static final class Entry {
+        final String path; final long size; final long ts;
+        Entry(String path, long size, long ts) {
+            this.path = path; this.size = size; this.ts = ts;
+        }
+    }
+}

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

@@ -11,6 +11,7 @@ import java.util.concurrent.BlockingQueue;
 
 public class IncomingMessageListener implements Runnable {
     private final BufferedReader in;
+    private volatile boolean running = true;
 
     public IncomingMessageListener(BufferedReader in) {
         this.in = in;
@@ -21,15 +22,41 @@ public class IncomingMessageListener implements Runnable {
         try {
             System.out.println("👂 Real-Time Listener started.");
 
-            String line;
+            while (running) {
-            while ((line = in.readLine()) != null) {
+                // ✅ اگر دانلود/آپلود مدیا در حال انجامه، اصلاً نخون
+                if (TelegramClient.mediaBusy.get()) {
+                    try { Thread.sleep(15); } catch (InterruptedException ignored) {}
+                    continue;
+                }
 
+                // ✅ فقط وقتی دادهٔ متنی آماده است بخوان (بدون بلاک شدن روی readLine)
+                if (!in.ready()) {
+                    try { Thread.sleep(10); } catch (InterruptedException ignored) {}
+                    continue;
+                }
+
+                String line = in.readLine();
+                if (line == null) {
+                    // socket بسته شده
+                    break;
+                }
+
+                // خط‌های خالی/سفید رو رد کن
+                if (line.isBlank()) continue;
+
+                // تلاش برای پارس JSON
+                final JSONObject response;
+                try {
+                    response = new JSONObject(line);
+                } catch (Exception badJson) {
+                    // اگر به هر دلیلی خط JSON نبود (مثلاً نویز)، امن رد کن
+                    System.out.println("⚠️ [Listener] Non-JSON line ignored: " + line);
+                    continue;
+                }
 
-                JSONObject response = new JSONObject(line);
                 System.out.println("📥 Received raw line: " + line);
 
-
+                // --- Media ACK routing by message_id ---
-                //for media
                 String mid = response.optString("message_id", "");
                 if (!mid.isEmpty()) {
                     BlockingQueue<JSONObject> q = TelegramClient.pendingResponses.get(mid);
@@ -39,9 +66,9 @@ public class IncomingMessageListener implements Runnable {
                     }
                 }
 
-               //if it has reqID answer
+                // --- General request_id response routing ---
                 if (response.has("request_id")) {
-                    String requestId = response.getString("request_id");
+                    String requestId = response.optString("request_id", "");
                     System.out.println("📬 Response with request_id: " + requestId);
                     System.out.println("📬 Full response: " + response.toString(2));
 
@@ -52,15 +79,12 @@ public class IncomingMessageListener implements Runnable {
                         System.out.println("⚠️ No pending queue for request_id = " + requestId + ". Putting in responseQueue...");
                         TelegramClient.responseQueue.put(response);
                     }
-
                     continue;
                 }
 
-
+                // --- Real-time actions ---
-
-                //if it has action check it
                 if (response.has("action")) {
-                    String action = response.getString("action");
+                    String action = response.optString("action", "");
                     System.out.println("🎯 [Listener] Action received: " + response.toString(2));
                     System.out.println("🎯 Received action: " + action);
 
@@ -69,11 +93,12 @@ public class IncomingMessageListener implements Runnable {
                     } else {
                         TelegramClient.responseQueue.put(response);
                     }
-
                 } else if (response.has("status") && response.has("message")) {
-                    TelegramClient.responseQueue.put(response); // general answer
+                    // General success/error
+                    TelegramClient.responseQueue.put(response);
                 } else {
-                    TelegramClient.responseQueue.put(response); // fallback
+                    // Fallback
+                    TelegramClient.responseQueue.put(response);
                 }
             }
 
@@ -90,26 +115,30 @@ public class IncomingMessageListener implements Runnable {
                  "update_group_or_channel", "chat_deleted",
                  "blocked_by_user", "unblocked_by_user", "message_seen",
                  "removed_from_group", "removed_from_channel",
-                 "became_admin", "removed_admin", "ownership_transferred","admin_permissions_updated","created_private_chat" , "message_reacted" , "message_unreacted" -> true;
+                 "became_admin", "removed_admin", "ownership_transferred",
+                 "admin_permissions_updated", "created_private_chat",
+                 "message_reacted", "message_unreacted" -> true;
             default -> false;
         };
     }
 
     void handleRealTimeEvent(JSONObject response) throws IOException {
-        String action = response.getString("action");
+        String action = response.optString("action", "");
-        JSONObject msg = response.has("data") ? response.getJSONObject("data") : new JSONObject();
+        JSONObject msg = response.has("data") ? response.optJSONObject("data") : new JSONObject();
-
 
         switch (action) {
             case "added_to_group", "added_to_channel",
-                 "removed_from_group", "removed_from_channel", "chat_deleted","created_private_chat" -> {
+                 "removed_from_group", "removed_from_channel",
+                 "chat_deleted", "created_private_chat" -> {
                 System.out.println("🔄 Chat list changed. Updating...");
                 Session.forceRefreshChatList = true;
                 System.out.println("🧪 Calling requestChatList() after being added");
 
-                String chatId = msg.getString("chat_id");
+                String chatId = msg.optString("chat_id", "");
-                String chatType = msg.getString("chat_type");
+                String chatType = msg.optString("chat_type", "");
+                if (!chatId.isBlank() && !chatType.isBlank()) {
                     ActionHandler.requestChatInfo(chatId, chatType);
+                }
 
                 if (action.equals("removed_from_group") || action.equals("removed_from_channel") || action.equals("chat_deleted")) {
                     System.out.println("🚫 You were removed from the chat or chat was deleted. Exiting...");
@@ -119,33 +148,22 @@ public class IncomingMessageListener implements Runnable {
 
             case "chat_updated" -> {
                 System.out.println("\n🔄 Chat info updated.");
-
                 if (msg.has("last_message_time")) {
                     updateLastMessageTime(msg);
                 } else {
                     new Thread(() -> {
-                        try {
+                        try { handleAdminRoleChanged(msg); } catch (IOException e) { e.printStackTrace(); }
-                            handleAdminRoleChanged(msg);
-                        } catch (IOException e) {
-                            e.printStackTrace();
-                        }
                     }).start();
                 }
             }
 
-
+            case "became_admin", "removed_admin", "ownership_transferred", "admin_permissions_updated" -> {
-            case "became_admin", "removed_admin", "ownership_transferred","admin_permissions_updated" -> {
                 System.out.println("🧩 Detected admin/owner role change. Calling handler...");
                 new Thread(() -> {
-                    try {
+                    try { handleAdminRoleChanged(msg); } catch (IOException e) { e.printStackTrace(); }
-                        handleAdminRoleChanged(msg); //new thread
-                    } catch (IOException e) {
-                        e.printStackTrace();
-                    }
                 }).start();
             }
 
-
             default -> displayRealTimeMessage(action, msg);
         }
 
@@ -157,25 +175,19 @@ public class IncomingMessageListener implements Runnable {
             UUID chatUUID = UUID.fromString(msg.getString("chat_id"));
             String newTime = msg.optString("last_message_time", null);
 
-            Session.chatList.stream()
+            Session.chatList.stream().filter(chat -> chat.getId().equals(chatUUID)).findFirst()
-                    .filter(chat -> chat.getId().equals(chatUUID))
-                    .findFirst()
                     .ifPresent(chat -> {
                         chat.setLastMessageTime(newTime);
                         System.out.println("✅ Updated last message time for chat: " + chat.getDisplayId());
                     });
 
-            Session.activeChats.stream()
+            Session.activeChats.stream().filter(chat -> chat.getId().equals(chatUUID)).findFirst()
-                    .filter(chat -> chat.getId().equals(chatUUID))
-                    .findFirst()
                     .ifPresent(chat -> {
                         chat.setLastMessageTime(newTime);
                         System.out.println("✅ Updated last message time for chat: " + chat.getDisplayId());
                     });
 
-            Session.archivedChats.stream()
+            Session.archivedChats.stream().filter(chat -> chat.getId().equals(chatUUID)).findFirst()
-                    .filter(chat -> chat.getId().equals(chatUUID))
-                    .findFirst()
                     .ifPresent(chat -> {
                         chat.setLastMessageTime(newTime);
                         System.out.println("✅ Updated last message time for chat: " + chat.getDisplayId());
@@ -185,24 +197,21 @@ public class IncomingMessageListener implements Runnable {
                 if (c1.getLastMessageTime() == null && c2.getLastMessageTime() == null) return 0;
                 if (c1.getLastMessageTime() == null) return 1;
                 if (c2.getLastMessageTime() == null) return -1;
-                return c2.getLastMessageTime().compareTo(c1.getLastMessageTime()); // descending
+                return c2.getLastMessageTime().compareTo(c1.getLastMessageTime());
             });
             Session.activeChats.sort((c1, c2) -> {
                 if (c1.getLastMessageTime() == null && c2.getLastMessageTime() == null) return 0;
                 if (c1.getLastMessageTime() == null) return 1;
                 if (c2.getLastMessageTime() == null) return -1;
-                return c2.getLastMessageTime().compareTo(c1.getLastMessageTime()); // descending
+                return c2.getLastMessageTime().compareTo(c1.getLastMessageTime());
             });
             Session.archivedChats.sort((c1, c2) -> {
                 if (c1.getLastMessageTime() == null && c2.getLastMessageTime() == null) return 0;
                 if (c1.getLastMessageTime() == null) return 1;
                 if (c2.getLastMessageTime() == null) return -1;
-                return c2.getLastMessageTime().compareTo(c1.getLastMessageTime()); // descending
+                return c2.getLastMessageTime().compareTo(c1.getLastMessageTime());
             });
 
-
-
-
             if (Session.inChatListMenu) {
                 ActionHandler.displayChatList();
                 System.out.print("Select a chat by number: ");
@@ -213,12 +222,12 @@ public class IncomingMessageListener implements Runnable {
         }
     }
 
-
     private void handleAdminRoleChanged(JSONObject data) throws IOException {
-        String chatType = data.getString("chat_type");
+        String chatType = data.optString("chat_type", "");
-        String chatId = data.optString("group_id", data.optString("channel_id", data.optString("chat_id", null)));
+        String chatId = data.optString("group_id",
+                data.optString("channel_id", data.optString("chat_id", "")));
 
-        if (chatId == null) {
+        if (chatId.isBlank()) {
             System.out.println("⚠️ No valid ID found in real-time data: " + data.toString(2));
             return;
         }
@@ -226,11 +235,10 @@ public class IncomingMessageListener implements Runnable {
         System.out.println("\n🔄 Your admin status changed. Updating chat info...");
 
         try {
-            // 1. get chat info
+            JSONObject chatInfoReq = new JSONObject()
-            JSONObject chatInfoReq = new JSONObject();
+                    .put("action", "get_chat_info")
-            chatInfoReq.put("action", "get_chat_info");
+                    .put("receiver_id", chatId)
-            chatInfoReq.put("receiver_id", chatId);
+                    .put("receiver_type", chatType);
-            chatInfoReq.put("receiver_type", chatType);
             System.out.println("📤 Sending get_chat_info: " + chatInfoReq);
             JSONObject chatInfoResp = ActionHandler.sendWithResponse(chatInfoReq);
             JSONObject chatData = chatInfoResp.getJSONObject("data");
@@ -256,21 +264,17 @@ public class IncomingMessageListener implements Runnable {
                 Session.currentChatEntry = chat;
             });
 
-            // 2. get permission
             JSONObject permissionReq = new JSONObject();
             if (chatType.equalsIgnoreCase("group")) {
-                permissionReq.put("action", "get_group_permissions");
+                permissionReq.put("action", "get_group_permissions").put("group_id", chatId);
-                permissionReq.put("group_id", chatId);
             } else {
-                permissionReq.put("action", "get_channel_permissions");
+                permissionReq.put("action", "get_channel_permissions").put("channel_id", chatId);
-                permissionReq.put("channel_id", chatId);
             }
 
             JSONObject permissionResp = ActionHandler.sendWithResponse(permissionReq);
             JSONObject perm = permissionResp.getJSONObject("data");
             entry.ifPresent(chat -> chat.setPermissions(perm));
 
-            // 3. set currentChatId
             Session.currentChatId = chatUUID.toString();
 
             System.out.println("🧪 Checking refresh conditions...");
@@ -293,20 +297,11 @@ public class IncomingMessageListener implements Runnable {
         }
     }
 
-
-
-
-
-
-
-
-
-
     private void displayRealTimeMessage(String action, JSONObject msg) {
         switch (action) {
             case "new_message" -> {
                 String senderName = msg.optString("sender_name","Unknown");
-                String content    = msg.optString("content","(empty)");
+                String content    = msg.optString("content","");
                 String sendAt     = msg.optString("send_at","-");
                 String chatId     = msg.optString("receiver_id", msg.optString("chat_id",""));
                 String kind       = msg.optString("kind","plain");
@@ -325,47 +320,47 @@ public class IncomingMessageListener implements Runnable {
                         Session.currentChatId != null && Session.currentChatId.equals(chatId);
 
                 if (isInCurrentChat) {
+                    if (content.isBlank()) content = "(no content)"; // برای مدیا بدون کپشن
                     System.out.println(senderName + ": " + prefix + content + "   (" + sendAt + ")");
                 } else {
-                    System.out.println("💬 Message from " + senderName + ": " + prefix + content);
+                    String preview = content.isBlank() ? "[media]" : content;
+                    System.out.println("💬 Message from " + senderName + ": " + prefix + preview);
                     Session.forceRefreshChatList = true;
                 }
             }
 
-
             case "message_edited" -> {
                 System.out.println("\n✏️ Message Edited:");
-                System.out.println("ID: " + msg.getString("message_id"));
+                System.out.println("ID: " + msg.optString("message_id",""));
-                System.out.println("New Content: " + msg.getString("new_content"));
+                System.out.println("New Content: " + msg.optString("new_content",""));
-                System.out.println("Edit Time: " + msg.getString("edited_at"));
+                System.out.println("Edit Time: " + msg.optString("edited_at",""));
             }
             case "message_deleted_global" -> {
                 System.out.println("\n🗑️ Message Deleted:");
-                System.out.println("Message ID: " + msg.getString("message_id"));
+                System.out.println("Message ID: " + msg.optString("message_id",""));
             }
             case "message_reacted", "message_unreacted" -> {
-                String mid    = msg.getString("message_id");
+                String mid    = msg.optString("message_id","");
-                String emoji  = msg.getString("emoji");
+                String emoji  = msg.optString("emoji","");
-                JSONObject counts = msg.optJSONObject("counts");
                 int n = msg.optInt("count_for_emoji", 0);
                 System.out.println("\n⭐ Reaction update on " + mid + " : " + emoji + " → " + n);
             }
 
             case "user_status_changed" -> {
                 System.out.println("\n🔄 User Status Changed:");
-                System.out.println("User: " + msg.getString("user_id"));
+                System.out.println("User: " + msg.optString("user_id",""));
-                System.out.println("Status: " + msg.getString("status"));
+                System.out.println("Status: " + msg.optString("status",""));
             }
             case "blocked_by_user" -> {
-                System.out.println("\n⛔ You were blocked by user: " + msg.getString("blocker_id"));
+                System.out.println("\n⛔ You were blocked by user: " + msg.optString("blocker_id",""));
             }
             case "unblocked_by_user" -> {
-                System.out.println("\n✅ You were unblocked by user: " + msg.getString("unblocker_id"));
+                System.out.println("\n✅ You were unblocked by user: " + msg.optString("unblocker_id",""));
             }
             case "message_seen" -> {
                 System.out.println("\n👁️ Your message was seen:");
-                System.out.println("Message ID: " + msg.getString("message_id"));
+                System.out.println("Message ID: " + msg.optString("message_id",""));
-                System.out.println("Seen at: " + msg.getString("seen_at"));
+                System.out.println("Seen at: " + msg.optString("seen_at",""));
             }
             default -> {
                 System.out.println("\n❓ Unknown real-time action: " + action);

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

@@ -28,7 +28,7 @@ public class Session {
     public static ChatEntry currentChatEntry = null;
     public static List<ContactEntry> contactEntries = new ArrayList<>();
     public static boolean inContactListMenu = false;
-
+    public static DownloadsIndex downloadsIndex = null;
 
     public static String getUserUUID() {
         if (currentUser.has("uuid")) return currentUser.getString("uuid");
@@ -110,4 +110,7 @@ public class Session {
                 .filter(ChatEntry::isArchived)
                 .toList();
     }
+
+    public void setDownloadIndex(DownloadsIndex idx){ this.downloadsIndex = idx; }
+
 }

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

@@ -0,0 +1,78 @@
+package org.to.telegramfinalproject.Client;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.PrintWriter;
+
+public final class SocketMediaDownloader {
+    private static final int MAGIC_DL = 0x4D444D32;
+    private final PrintWriter outText;         // NEW
+    private final DataInputStream inBin;
+    private final DataOutputStream outBin;
+
+    public SocketMediaDownloader(PrintWriter outText, DataInputStream inBin, DataOutputStream outBin) {
+        this.outText = outText;
+        this.inBin = inBin;
+        this.outBin = outBin;
+    }
+
+
+    public java.nio.file.Path download(java.util.UUID mediaKey, java.nio.file.Path saveDir, String fileNameHint) throws Exception {
+        // 1) سوییچ مود با PrintWriter
+        outText.print("MEDIA_DL\n");
+        outText.flush();
+
+        // 2) هدر باینری درخواست
+        org.json.JSONObject req = new org.json.JSONObject()
+                .put("op","download")
+                .put("media_key", mediaKey.toString())
+                .put("offset", 0);
+        byte[] hb = req.toString().getBytes(java.nio.charset.StandardCharsets.UTF_8);
+
+        outBin.writeInt(MAGIC_DL);
+        outBin.writeInt(hb.length);
+        outBin.write(hb);
+        outBin.flush();
+
+        // 3) پاسخ
+        int magic = inBin.readInt();
+        if (magic != MAGIC_DL) throw new java.io.IOException("bad magic");
+
+        int hlen = inBin.readInt();
+        byte[] hbytes = inBin.readNBytes(hlen);
+        org.json.JSONObject hdr = new org.json.JSONObject(new String(hbytes, java.nio.charset.StandardCharsets.UTF_8));
+        if (!"success".equalsIgnoreCase(hdr.optString("status"))) {
+            throw new java.io.IOException("download error: " + hdr.optString("message"));
+        }
+
+        long contentLen = inBin.readLong();
+        String serverName = hdr.optString("file_name", fileNameHint != null ? fileNameHint : mediaKey.toString());
+
+        java.nio.file.Files.createDirectories(saveDir);
+        java.nio.file.Path dest = uniquePath(saveDir, serverName);
+
+        try (java.io.OutputStream os = java.nio.file.Files.newOutputStream(dest)) {
+            byte[] buf = new byte[8192];
+            long remain = contentLen;
+            while (remain > 0) {
+                int toRead = (int) Math.min(buf.length, remain);
+                int n = inBin.read(buf, 0, toRead);
+                if (n == -1) throw new java.io.EOFException("unexpected EOF");
+                os.write(buf, 0, n);
+                remain -= n;
+            }
+        }
+        return dest;
+    }
+
+    private static java.nio.file.Path uniquePath(java.nio.file.Path dir, String name) throws java.io.IOException {
+        java.nio.file.Path p = dir.resolve(name);
+        if (!java.nio.file.Files.exists(p)) return p;
+        String base = name, ext = "";
+        int dot = name.lastIndexOf('.');
+        if (dot >= 0) { base = name.substring(0, dot); ext = name.substring(dot); }
+        int i = 1;
+        while (java.nio.file.Files.exists(dir.resolve(base + " (" + i + ")" + ext))) i++;
+        return dir.resolve(base + " (" + i + ")" + ext);
+    }
+}

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

@@ -4,12 +4,14 @@ import org.json.JSONObject;
 
 import java.io.*;
 import java.net.Socket;
+import java.nio.charset.StandardCharsets;
 import java.util.Map;
 import java.util.Scanner;
 import java.util.UUID;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.atomic.AtomicBoolean;
 
 public class TelegramClient {
     private static final String SERVER_HOST = "localhost";
@@ -22,7 +24,10 @@ public class TelegramClient {
     public static BlockingQueue<JSONObject> responseQueue = new LinkedBlockingQueue<>();
     public static UUID loggedInUserId = null;
     public static final Map<String, BlockingQueue<JSONObject>> pendingResponses = new ConcurrentHashMap<>();
-
+    private DataInputStream inBin;                     // NEW
+    private static SocketMediaDownloader downloader;   // NEW
+    public static final AtomicBoolean mediaBusy = new AtomicBoolean(false); //
+    private DownloadsIndex downloadIndex;
 
     private static TelegramClient instance;
 
@@ -31,6 +36,10 @@ public class TelegramClient {
         instance = this;
     }
 
+    public static SocketMediaDownloader getDownloader() {
+        return downloader;
+    }
+
     public static TelegramClient getInstance() {
         return instance;
     }
@@ -39,9 +48,14 @@ public class TelegramClient {
     public void start() {
         try {
             socket = new Socket(SERVER_HOST, SERVER_PORT);
-            in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
+            InputStream rawIn  = socket.getInputStream();
-            out = new PrintWriter(socket.getOutputStream(), true);
+            OutputStream rawOut = socket.getOutputStream();
-            outBin = new DataOutputStream(new BufferedOutputStream(socket.getOutputStream())); // برای MEDIA
+            in  = new BufferedReader(new InputStreamReader(rawIn, StandardCharsets.UTF_8));
+            out = new PrintWriter(new OutputStreamWriter(rawOut, StandardCharsets.UTF_8), true);
+
+            inBin  = new DataInputStream(rawIn);
+            outBin = new DataOutputStream(rawOut);
+            downloader = new SocketMediaDownloader(out, inBin, outBin);
 
             System.out.println("✅ Connected to Telegram Server");
             handler = new ActionHandler(out, in, outBin, scanner);
@@ -78,7 +92,7 @@ public class TelegramClient {
 
                         UUID internalId = UUID.fromString(Session.currentUser.getString("internal_uuid"));
                         loggedInUserId = internalId;
-
+                        this.downloadIndex = DownloadIndexRegistry.forAccount(internalId);
                         handler.userMenu(internalId);
                     } else {
                         System.out.println("❌ Login failed.");
@@ -120,3 +134,4 @@ public class TelegramClient {
     }
 
 }
+

src/main/java/org/to/telegramfinalproject/Database/ChannelDatabase.java

@@ -195,7 +195,7 @@ public class ChannelDatabase {
         """;
 
         try (Connection conn = ConnectionDb.connect()) {
-            // مرحله اول: ساخت کانال
+
             PreparedStatement stmt = conn.prepareStatement(sql);
             stmt.setString(1, channel.getChannel_id());
             stmt.setString(2, channel.getChannel_name());
@@ -208,9 +208,8 @@ public class ChannelDatabase {
             if (!rs.next()) return false;
 
             UUID internalUUID = (UUID) rs.getObject("internal_uuid");
-            channel.setInternal_uuid(internalUUID); // اختیاری برای پیگیری بعدی
+            channel.setInternal_uuid(internalUUID);
 
-            // مرحله دوم: افزودن کاربر به لیست سابسکرایبرها
             PreparedStatement subStmt = conn.prepareStatement(subscriberSql);
             subStmt.setObject(1, internalUUID);
             subStmt.setObject(2, creatorId);

src/main/java/org/to/telegramfinalproject/Database/MessageDatabase.java

@@ -1,14 +1,12 @@
 package org.to.telegramfinalproject.Database;
 
 import org.to.telegramfinalproject.Models.FileAttachment;
+import org.to.telegramfinalproject.Models.MediaRow;
 import org.to.telegramfinalproject.Models.Message;
 
 import java.sql.*;
 import java.time.LocalDateTime;
-import java.util.ArrayList;
+import java.util.*;
-import java.util.Collections;
-import java.util.List;
-import java.util.UUID;
 import java.util.stream.Collectors;
 
 public class MessageDatabase {
@@ -1197,4 +1195,171 @@ public class MessageDatabase {
         }
     }
 
+
+//
+//    public static MediaRow findMediaByKey(UUID mediaKey) throws SQLException {
+//        final String sql = """
+//        SELECT a.message_id, a.storage_path, a.file_name, a.mime_type, a.file_size,
+//               m.receiver_type, m.receiver_id, m.sender_id
+//        FROM message_attachments a
+//        JOIN messages m ON m.message_id = a.message_id
+//        WHERE a.media_key = ?
+//    """;
+//        try (Connection c = ConnectionDb.connect();
+//             PreparedStatement ps = c.prepareStatement(sql)) {
+//            ps.setObject(1, mediaKey);
+//            try (ResultSet rs = ps.executeQuery()) {
+//                if (!rs.next()) return null;
+//                MediaRow mr = new MediaRow();
+//                mr.messageId   = (UUID) rs.getObject(1);
+//                mr.storagePath = rs.getString(2);
+//                mr.fileName    = rs.getString(3);
+//                mr.mimeType    = rs.getString(4);
+//                mr.fileSize    = rs.getLong(5);
+//                mr.receiverType= rs.getString(6);
+//                mr.receiverId  = (UUID) rs.getObject(7);
+//                mr.senderId    = (UUID) rs.getObject(8);
+//                return mr;
+//            }
+//        }
+//    }
+
+//    public static boolean canAccess(UUID requester, MediaRow mr) {
+//        if ("private".equals(mr.receiverType)) {
+//            return requester.equals(mr.senderId) || requester.equals(mr.receiverId);
+//        } else if ("group".equals(mr.receiverType)) {
+//            return GroupDatabase.isMember(mr.receiverId, requester);
+//        } else if ("channel".equals(mr.receiverType)) {
+//            return ChannelDatabase.isUserInChannel(mr.receiverId, requester);
+//        }
+//        return false;
+//    }
+
+    public static Map<UUID, List<MediaRow>> findAttachmentsForMessages(List<UUID> ids) throws SQLException {
+        Map<UUID, List<MediaRow>> map = new java.util.HashMap<>();
+        if (ids == null || ids.isEmpty()) return map;
+
+        // ساخت IN به‌صورت امن
+        String placeholders = ids.stream().map(x -> "?").collect(java.util.stream.Collectors.joining(","));
+        String sql = """
+        SELECT attachment_id, message_id, media_key, file_name, file_size, mime_type, file_type,
+               width, height, duration_seconds, thumbnail_url, file_url, storage_path
+        FROM message_attachments
+        WHERE message_id IN (""" + placeholders + ") ORDER BY uploaded_at ASC";
+
+        try (Connection c = ConnectionDb.connect();
+             PreparedStatement ps = c.prepareStatement(sql)) {
+            int i = 1;
+            for (UUID id : ids) ps.setObject(i++, id);
+            try (ResultSet rs = ps.executeQuery()) {
+                while (rs.next()) {
+                    MediaRow a = new MediaRow();
+                    a.attachmentId    = (UUID) rs.getObject("attachment_id");
+                    a.messageId       = (UUID) rs.getObject("message_id");
+                    a.mediaKey        = (UUID) rs.getObject("media_key");
+                    a.fileName        = rs.getString("file_name");
+                    long sz           = rs.getLong("file_size");
+                    a.fileSize        = rs.wasNull() ? null : sz;
+                    a.mimeType        = rs.getString("mime_type");
+                    a.fileType        = rs.getString("file_type");
+                    int w             = rs.getInt("width");
+                    a.width           = rs.wasNull() ? null : w;
+                    int h             = rs.getInt("height");
+                    a.height          = rs.wasNull() ? null : h;
+                    int d             = rs.getInt("duration_seconds");
+                    a.durationSeconds = rs.wasNull() ? null : d;
+                    a.thumbnailUrl    = rs.getString("thumbnail_url");
+                    a.fileUrl         = rs.getString("file_url");
+                    a.storagePath     = rs.getString("storage_path");
+
+                    map.computeIfAbsent(a.messageId, k -> new java.util.ArrayList<>()).add(a);
+                }
+            }
+        }
+        return map;
+    }
+
+
+
+
+
+    public static MediaRow findMediaByKey(UUID mediaKey) throws SQLException {
+        String sql = """
+        SELECT
+          ma.attachment_id,
+          ma.message_id,
+          ma.media_key,
+          ma.file_name,
+          ma.file_size,
+          ma.mime_type,
+          ma.file_type,
+          ma.width,
+          ma.height,
+          ma.duration_seconds,
+          ma.thumbnail_url,
+          ma.file_url,
+          ma.storage_path,
+          m.receiver_type,
+          m.receiver_id,
+          m.sender_id
+        FROM message_attachments ma
+        JOIN messages m ON m.message_id = ma.message_id
+        WHERE ma.media_key = ?
+        LIMIT 1
+    """;
+
+        try (Connection c = ConnectionDb.connect();
+             PreparedStatement ps = c.prepareStatement(sql)) {
+            ps.setObject(1, mediaKey);
+            try (ResultSet rs = ps.executeQuery()) {
+                if (!rs.next()) return null;
+
+                MediaRow a = new MediaRow();
+                a.attachmentId    = (UUID) rs.getObject("attachment_id");
+                a.messageId       = (UUID) rs.getObject("message_id");
+                a.mediaKey        = (UUID) rs.getObject("media_key");
+                a.fileName        = rs.getString("file_name");
+
+                long sz = rs.getLong("file_size");
+                a.fileSize = rs.wasNull() ? null : sz; // MediaRow.fileSize = Long
+
+                a.mimeType        = rs.getString("mime_type");
+                a.fileType        = rs.getString("file_type");
+                int w = rs.getInt("width");            a.width  = rs.wasNull() ? null : w;
+                int h = rs.getInt("height");           a.height = rs.wasNull() ? null : h;
+                int d = rs.getInt("duration_seconds"); a.durationSeconds = rs.wasNull() ? null : d;
+                a.thumbnailUrl    = rs.getString("thumbnail_url");
+                a.fileUrl         = rs.getString("file_url");
+                a.storagePath     = rs.getString("storage_path");
+                a.receiverType    = rs.getString("receiver_type");
+                a.receiverId      = (UUID) rs.getObject("receiver_id");
+                a.senderId        = (UUID) rs.getObject("sender_id");
+                return a;
+            }
+        }
+    }
+
+
+    public static boolean canAccess(UUID requester, MediaRow mr) {
+        if (requester == null || mr == null || mr.receiverType == null) return false;
+
+        // اختیاری: فرستنده همیشه مجاز
+        if (requester.equals(mr.senderId)) return true;
+
+        switch (mr.receiverType.toLowerCase(Locale.ROOT)) {
+            case "private":
+                // receiver_id در پیام‌های private = UUID چت خصوصی
+                return PrivateChatDatabase.isParticipant(mr.receiverId, requester);
+
+            case "group":
+                return GroupDatabase.isMember(mr.receiverId, requester);
+
+            case "channel":
+                return ChannelDatabase.isUserInChannel(mr.receiverId, requester);
+
+            default:
+                return false;
+        }
+    }
+
 }

src/main/java/org/to/telegramfinalproject/Database/MessageReactionDatabase.java

@@ -1,6 +1,7 @@
 package org.to.telegramfinalproject.Database;
 
 import org.json.JSONObject;
+import org.to.telegramfinalproject.Models.MediaRow;
 
 import java.sql.Connection;
 import java.sql.PreparedStatement;
@@ -8,6 +9,7 @@ import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.UUID;
 
 public class MessageReactionDatabase {
@@ -73,4 +75,8 @@ public class MessageReactionDatabase {
         return counts; // مثال: {"❤️":2,"👍":1}
     }
 
+
+
+
+
 }

src/main/java/org/to/telegramfinalproject/Database/PrivateChatDatabase.java

@@ -315,4 +315,27 @@ public class PrivateChatDatabase {
         return null;
     }
 
+    public static boolean isParticipant(java.util.UUID chatId, java.util.UUID userId) {
+        String sql = """
+        SELECT 1
+        FROM private_chat
+        WHERE chat_id = ?
+          AND (user1_id = ? OR user2_id = ?)
+        LIMIT 1
+    """;
+        try (var c = ConnectionDb.connect();
+             var ps = c.prepareStatement(sql)) {
+            ps.setObject(1, chatId);
+            ps.setObject(2, userId);
+            ps.setObject(3, userId);
+            try (var rs = ps.executeQuery()) {
+                return rs.next();
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+            return false;
+        }
+    }
+
+
 }

src/main/java/org/to/telegramfinalproject/Models/MediaRow.java

@@ -0,0 +1,22 @@
+package org.to.telegramfinalproject.Models;
+
+import java.util.UUID;
+
+public class MediaRow {
+    public UUID messageId;
+    public String storagePath;
+    public String fileName;
+    public String mimeType;
+    public Long fileSize;
+    public String receiverType;
+    public UUID receiverId;
+    public UUID senderId;
+    public java.util.UUID attachmentId;
+    public java.util.UUID mediaKey;
+    public String fileType; // IMAGE/AUDIO/...
+    public Integer width;
+    public Integer height;
+    public Integer durationSeconds; //for audio only
+    public String thumbnailUrl;
+    public String fileUrl;     //display link
+}

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

@@ -32,12 +32,31 @@ public class ClientHandler implements Runnable {
         UUID userId = null;
 
         try (
+
+//                InputStream  rawIn  = socket.getInputStream();
+//                OutputStream rawOut = socket.getOutputStream();
+//
+//                BufferedReader in = new BufferedReader(new InputStreamReader(rawIn, java.nio.charset.StandardCharsets.UTF_8));
+//                PrintWriter    out = new PrintWriter(new OutputStreamWriter(rawOut, java.nio.charset.StandardCharsets.UTF_8), true);
+
+//                DataInputStream  dis  = new DataInputStream(rawIn);
+//                DataOutputStream dos  = new DataOutputStream(new BufferedOutputStream(rawOut));
+
 //                BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
 //                PrintWriter out = new PrintWriter(socket.getOutputStream(), true)
-                BufferedInputStream bis = new BufferedInputStream(socket.getInputStream());
+//                BufferedInputStream bis = new BufferedInputStream(socket.getInputStream());
-                DataInputStream dis = new DataInputStream(bis); //for binary headers
+               // DataInputStream dis = new DataInputStream(bis); //for binary headers
 
-                PrintWriter out = new PrintWriter(new OutputStreamWriter(socket.getOutputStream(), java.nio.charset.StandardCharsets.UTF_8), true);
+                //PrintWriter out = new PrintWriter(new OutputStreamWriter(socket.getOutputStream(), java.nio.charset.StandardCharsets.UTF_8), true);
+               InputStream  rawIn  = socket.getInputStream();
+               OutputStream rawOut = socket.getOutputStream();
+
+               BufferedInputStream  bis = new BufferedInputStream(rawIn);
+               BufferedOutputStream bos = new BufferedOutputStream(rawOut);
+
+               DataInputStream  dis = new DataInputStream(bis);
+               DataOutputStream dos = new DataOutputStream(bos);
+               PrintWriter      out = new PrintWriter(new OutputStreamWriter(bos, java.nio.charset.StandardCharsets.UTF_8), true);
 
         ) {
 
@@ -45,11 +64,23 @@ public class ClientHandler implements Runnable {
 
             String inputLine;
             while ((inputLine = readUtf8Line(bis)) != null) {
+
+                String line = inputLine.trim();
+
                 if ("MEDIA".equalsIgnoreCase(inputLine.trim())) {
                     handleMediaFrame(dis, out);
                     continue;
                 }
 
+                if ("MEDIA_DL".equalsIgnoreCase(line)) {
+                    if (this.currentUser.getInternal_uuid() == null) {
+                        sendDlErr(dos, "not authorized");
+                        continue;
+                    }
+                    handleMediaDownload(dis, dos, this.currentUser.getInternal_uuid());
+                    continue;
+                }
+
                 JSONObject requestJson = new JSONObject(inputLine);
                 String action = requestJson.getString("action");
                 ResponseModel response = null;
@@ -2144,6 +2175,13 @@ public class ClientHandler implements Runnable {
 
                         List<Message> messages = MessageDatabase.getMessagesForChat(chatId, chatType, currentUser.getInternal_uuid(), offset, limit);
 
+                        java.util.List<UUID> mids = new java.util.ArrayList<>();
+                        for (Message m : messages) mids.add(m.getMessage_id());
+
+                        // ⬅️ همهٔ اتچمنت‌ها را یک‌جا بگیر: message_id -> list(attachments)
+                        java.util.Map<UUID, java.util.List<MediaRow>> attMap =
+                                MessageDatabase.findAttachmentsForMessages(mids);
+
                         JSONArray result = new JSONArray();
                         for (Message m : messages) {
                             JSONObject obj = new JSONObject();
@@ -2211,6 +2249,26 @@ public class ClientHandler implements Runnable {
                             obj.put("reactions", new JSONArray(reactions));
 
 
+                            JSONArray atts = new JSONArray();
+                            java.util.List<MediaRow> list = attMap.getOrDefault(m.getMessage_id(), java.util.Collections.emptyList());
+                            for (MediaRow a : list) {
+                                JSONObject aj = new JSONObject()
+                                        .put("media_key", a.mediaKey != null ? a.mediaKey.toString() : JSONObject.NULL)
+                                        .put("file_name", a.fileName != null ? a.fileName : JSONObject.NULL)
+                                        .put("file_size", a.fileSize != null ? a.fileSize : JSONObject.NULL)
+                                        .put("mime_type", a.mimeType != null ? a.mimeType : JSONObject.NULL)
+                                        .put("file_type", a.fileType != null ? a.fileType : JSONObject.NULL)
+                                        .put("width",     a.width   != null ? a.width   : JSONObject.NULL)
+                                        .put("height",    a.height  != null ? a.height  : JSONObject.NULL)
+                                        .put("duration_seconds", a.durationSeconds != null ? a.durationSeconds : JSONObject.NULL)
+                                        .put("thumbnail_url", a.thumbnailUrl != null ? a.thumbnailUrl : JSONObject.NULL)
+                                        // اختیاری/دیباگ
+                                        .put("file_url", a.fileUrl != null ? a.fileUrl : JSONObject.NULL);
+                                atts.put(aj);
+                            }
+                            obj.put("attachments", atts);
+
+
                             result.put(obj);
                         }
 
@@ -2570,6 +2628,8 @@ public class ClientHandler implements Runnable {
                 userDatabase.updateLastSeen(userId);
                 SessionManager.removeUser(userId);
             }
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
         } finally {
             try {
                 if (currentUser != null) {
@@ -2863,6 +2923,75 @@ public class ClientHandler implements Runnable {
         }
     }
 
+    private static final int MAGIC_DL = 0x4D444D32; // "MDM2"
+
+    private void handleMediaDownload(DataInputStream inBin, DataOutputStream outBin, UUID requesterId) {
+        try {
+            int magic = inBin.readInt();
+            if (magic != MAGIC_DL) { sendDlErr(outBin, "bad magic"); return; }
+
+            int hlen = inBin.readInt();
+            if (hlen <= 0 || hlen > 64 * 1024) { sendDlErr(outBin, "bad header length"); return; }
+
+            byte[] hb = inBin.readNBytes(hlen);
+            if (hb.length != hlen) { sendDlErr(outBin, "header truncated"); return; }
+
+            JSONObject hdr = new JSONObject(new String(hb, java.nio.charset.StandardCharsets.UTF_8));
+            if (!"download".equalsIgnoreCase(hdr.optString("op"))) { sendDlErr(outBin, "bad op"); return; }
+
+            UUID mediaKey = UUID.fromString(hdr.getString("media_key"));
+            long offset   = Math.max(0L, hdr.optLong("offset", 0L));
+
+            MediaRow mr = MessageDatabase.findMediaByKey(mediaKey);
+            if (mr == null) { sendDlErr(outBin, "not found"); return; }
+            if (!MessageDatabase.canAccess(requesterId, mr)) { sendDlErr(outBin, "not authorized"); return; }
+
+            java.nio.file.Path path = java.nio.file.Paths.get(mr.storagePath).normalize();
+            long size = java.nio.file.Files.size(path);
+            if (offset > size) offset = 0L;
+
+            JSONObject ok = new JSONObject()
+                    .put("status","success")
+                    .put("media_key", mediaKey.toString())
+                    .put("file_name", mr.fileName)
+                    .put("mime_type", mr.mimeType)
+                    .put("file_size", size);
+
+            byte[] okb = ok.toString().getBytes(java.nio.charset.StandardCharsets.UTF_8);
+
+            outBin.writeInt(MAGIC_DL);
+            outBin.writeInt(okb.length);
+            outBin.write(okb);
+            outBin.writeLong(size - offset);
+
+            try (java.io.InputStream fis = new java.io.BufferedInputStream(java.nio.file.Files.newInputStream(path))) {
+                if (offset > 0) fis.skipNBytes(offset);
+                byte[] buf = new byte[8192];
+                long remain = size - offset;
+                while (remain > 0) {
+                    int n = fis.read(buf, 0, (int) Math.min(buf.length, remain));
+                    if (n == -1) break;
+                    outBin.write(buf, 0, n);
+                    remain -= n;
+                }
+            }
+            outBin.flush();
+
+        } catch (Exception e) {
+            e.printStackTrace();
+            try { sendDlErr(outBin, "exception"); } catch (Exception ignored) {}
+        }
+    }
+
+    private void sendDlErr(DataOutputStream outBin, String msg) throws java.io.IOException {
+        JSONObject j = new JSONObject().put("status","error").put("message", msg);
+        byte[] b = j.toString().getBytes(java.nio.charset.StandardCharsets.UTF_8);
+        outBin.writeInt(MAGIC_DL);
+        outBin.writeInt(b.length);
+        outBin.write(b);
+        outBin.writeLong(0L);
+        outBin.flush();
+    }
 
     private static void skip(DataInputStream dis, long n) throws IOException {
         if (n <= 0) return;