Message Logger: hidden messages on the server, removed chats, old chat photos

- Hidden deleted messages are marked on the server (local marks migrated);
  "Reveal hidden messages" in the chat menu, Unhide in the message menu and
  the selection bar.
- Chats an account lost are reported, listed among its chats again and
  opened read-only with their logged messages, all deleted.
- Logged chat photos: a removed chat's avatar, and in a chat's photos the
  ones it no longer has, translucent with a trash icon in the viewer's
  previews.
- Fix: the deleted-post comments thread is answered locally again.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/hooks/hidden.py

@@ -0,0 +1,202 @@
+"""Deleted messages removed from view ("hidden"), marked on the server so
+every client skips them; a chat can reveal its hidden messages again.
+
+- `flush` sends the marks waiting in the store to the server;
+- the chat menu toggles revealing (per chat, until the app restarts): the
+  hidden deleted messages come back from the logger, then go again;
+- a revealed hidden message has "Unhide" in its menu (hooks/menu.py), and
+  while revealing, the selection bar gets an Unhide button for those
+  selected (ChatActivity.createActionMode adds the bar's items,
+  updateActionModeTitle runs on every selection change; probed on 12.10.6).
+"""
+
+import threading
+
+from base_plugin import MethodHook
+
+import diag
+import peers
+import store
+from api import ApiError
+from jutil import field, hook_methods, in_background, on_ui
+
+CHAT = "org.telegram.ui.ChatActivity"
+_UNHIDE_ID = 0x4D4C01  # the selection bar item
+
+
+def _bulletin(text, error=False):
+    def show():
+        from ui.bulletin import BulletinHelper
+
+        (BulletinHelper.show_error if error else BulletinHelper.show_info)(text)
+
+    on_ui(show)
+
+
+def _selected(chat):
+    """MessageObjects selected in the chat (both halves of a merged chat)."""
+    out = []
+    for array in field(chat, "selectedMessagesIds") or []:
+        if array is None:
+            continue
+        for index in range(array.size()):
+            message = array.valueAt(index)
+            if message is not None:
+                out.append(message)
+    return out
+
+
+def is_revealed_hidden(message):
+    """A hidden deleted message shown because its chat reveals them."""
+    if message is None or int(message.getId()) <= 0:
+        return False
+    account, dialog_id = int(message.currentAccount), int(message.getDialogId())
+    message_id = int(message.getId())
+    return (
+        store.is_revealed(account, dialog_id)
+        and store.is_deleted(account, dialog_id, message_id)
+        and store.is_hidden(account, dialog_id, message_id)
+    )
+
+
+class Hidden:
+    def __init__(self, plugin, api, chats):
+        self.plugin = plugin
+        self.api = api
+        self.chats = chats  # hooks/chat.ChatSync
+        self.handles = []
+        self._flushing = threading.Lock()
+        self._items = {}  # ChatActivity classGuid -> the bar's Unhide item
+
+    def install(self):
+        hidden = self
+
+        class AfterActionMode(MethodHook):
+            def after_hooked_method(self, param):
+                try:
+                    hidden.add_bar_item(param.thisObject)
+                except Exception as exc:
+                    diag.error("hidden.bar", exc)
+
+        class AfterTitle(MethodHook):
+            def after_hooked_method(self, param):
+                try:
+                    hidden.update_bar_item(param.thisObject)
+                except Exception as exc:
+                    diag.error("hidden.title", exc)
+
+        self.handles += hook_methods(self.plugin, CHAT, "createActionMode", AfterActionMode())
+        self.handles += hook_methods(self.plugin, CHAT, "updateActionModeTitle", AfterTitle())
+        in_background(self.flush)
+
+    def uninstall(self):
+        for handle in self.handles:
+            try:
+                self.plugin.unhook_method(handle)
+            except Exception:
+                pass
+        self.handles = []
+
+    # the server
+
+    def flush(self):
+        """Sends hidden marks waiting in the store (background)."""
+        if not self.api.configured or not self._flushing.acquire(blocking=False):
+            return
+        try:
+            for (account, dialog_id, hidden), ids in store.pending_hidden().items():
+                me = peers.own_user_id(account)
+                chat_id = peers.marked_chat_id(account, dialog_id)
+                if not me or chat_id is None:
+                    continue
+                try:
+                    self.api.hidden(me, chat_id, ids, hidden)
+                except ApiError as exc:
+                    diag.log(f"hidden {chat_id}: {exc}")
+                    continue
+                store.hidden_sent(account, dialog_id, ids, hidden)
+                diag.log(f"{'hid' if hidden else 'unhid'} {chat_id}: {ids}")
+        finally:
+            self._flushing.release()
+
+    def hide(self, account, dialog_id, ids, hidden=True):
+        store.set_hidden(account, dialog_id, ids, hidden)
+        in_background(self.flush)
+
+    # revealing (chat menu)
+
+    def toggle_reveal(self, fragment):
+        account = int(fragment.getCurrentAccount())
+        dialog_id = int(fragment.getDialogId())
+        on = not store.is_revealed(account, dialog_id)
+        store.reveal(account, dialog_id, on)
+        if on:
+            count = self.chats.restore_hidden(fragment)
+            # And the server's answer, for those not cached.
+            store.expire_coverage(account, dialog_id)
+            self.chats.schedule(fragment)
+            _bulletin(
+                f"Message Logger: revealing hidden deleted messages ({count} loaded)"
+                if count
+                else "Message Logger: revealing hidden deleted messages"
+            )
+        else:
+            ids = store.hidden_deleted(account, dialog_id)
+            self.chats.drop_from_view(account, dialog_id, ids)
+            _bulletin("Message Logger: hidden deleted messages are hidden again")
+
+    # unhiding
+
+    def unhide(self, messages):
+        by_chat = {}
+        for message in messages:
+            if is_revealed_hidden(message):
+                key = (int(message.currentAccount), int(message.getDialogId()))
+                by_chat.setdefault(key, []).append(int(message.getId()))
+        for (account, dialog_id), ids in by_chat.items():
+            self.hide(account, dialog_id, ids, hidden=False)
+            self.chats.refresh_dialog(account, dialog_id, ids)
+        count = sum(len(ids) for ids in by_chat.values())
+        if count:
+            _bulletin(f"Message Logger: {count} message{'s' if count > 1 else ''} unhidden")
+
+    # the selection bar
+
+    def add_bar_item(self, chat):
+        """The bar's Unhide item (also for a chat opened before the plugin
+        loaded: its bar exists already)."""
+        bar = chat.getActionBar()
+        menu = bar.createActionMode() if bar is not None else None
+        if menu is None:
+            return None
+        from android.view import View
+        from android_utils import OnClickListener
+        from org.telegram.messenger import AndroidUtilities, R
+
+        item = menu.getItem(_UNHIDE_ID)
+        if item is None:
+            item = menu.addItemWithWidth(
+                _UNHIDE_ID, R.drawable.msg_views, AndroidUtilities.dp(54)
+            )
+            item.setContentDescription("Unhide")
+            item.setVisibility(View.GONE)
+
+        def chosen(_view):
+            self.unhide(_selected(chat))
+            chat.clearSelectionMode()
+
+        item.setOnClickListener(OnClickListener(chosen))
+        self._items[int(chat.getClassGuid())] = item
+        return item
+
+    def update_bar_item(self, chat):
+        item = self._items.get(int(chat.getClassGuid())) or self.add_bar_item(chat)
+        if item is None:
+            return
+        from android.view import View
+
+        account, dialog_id = int(chat.getCurrentAccount()), int(chat.getDialogId())
+        show = store.is_revealed(account, dialog_id) and any(
+            is_revealed_hidden(m) for m in _selected(chat)
+        )
+        item.setVisibility(View.VISIBLE if show else View.GONE)