Repair unread mention count in channels when a mention is read.

td/telegram/MessagesManager.cpp

@@ -5572,6 +5572,7 @@ void MessagesManager::Dialog::store(StorerT &storer) const {
     STORE_FLAG(has_history_generation);
     STORE_FLAG(need_repair_unread_reaction_count);
     STORE_FLAG(is_translatable);
+    STORE_FLAG(need_repair_unread_mention_count);
     END_STORE_FLAGS();
   }
 
@@ -5836,6 +5837,7 @@ void MessagesManager::Dialog::parse(ParserT &parser) {
     PARSE_FLAG(has_history_generation);
     PARSE_FLAG(need_repair_unread_reaction_count);
     PARSE_FLAG(is_translatable);
+    PARSE_FLAG(need_repair_unread_mention_count);
     END_PARSE_FLAGS();
   } else {
     need_repair_action_bar = false;
@@ -12429,8 +12431,23 @@ void MessagesManager::read_channel_message_content_from_updates(Dialog *d, Messa
   Message *m = get_message_force(d, message_id, "read_channel_message_content_from_updates");
   if (m != nullptr) {
     read_message_content(d, m, false, "read_channel_message_content_from_updates");
-  } else if (message_id > d->last_new_message_id && d->last_new_message_id.is_valid()) {
+  } else {
-    get_channel_difference(d->dialog_id, d->pts, true, "read_channel_message_content_from_updates");
+    if (!have_input_peer(d->dialog_id, AccessRights::Read)) {
+      LOG(INFO) << "Ignore updateChannelReadMessagesContents in inaccessible " << d->dialog_id;
+      if (d->unread_mention_count != 0) {
+        set_dialog_unread_mention_count(d, 0);
+      }
+      return;
+    }
+    if (message_id > d->last_new_message_id && d->last_new_message_id.is_valid()) {
+      get_channel_difference(d->dialog_id, d->pts, true, "read_channel_message_content_from_updates");
+    } else {
+      // there is no message, so the update can be ignored
+      if (d->unread_mention_count > 0) {
+        // but if the chat has unread mentions, then number of unread mentions could have been changed
+        repair_dialog_unread_mention_count(d, "read_channel_message_content_from_updates");
+      }
+    }
   }
 }
 
@@ -12604,6 +12621,20 @@ void MessagesManager::repair_dialog_unread_reaction_count(Dialog *d, Promise<Uni
   send_get_dialog_query(d->dialog_id, std::move(promise), 0, source);
 }
 
+void MessagesManager::repair_dialog_unread_mention_count(Dialog *d, const char *source) {
+  CHECK(d != nullptr);
+
+  if (td_->auth_manager_->is_bot()) {
+    return;
+  }
+  if (!d->need_repair_unread_mention_count) {
+    d->need_repair_unread_mention_count = true;
+    on_dialog_updated(d->dialog_id, "repair_dialog_unread_mention_count");
+  }
+
+  send_get_dialog_query(d->dialog_id, Promise<Unit>(), 0, source);
+}
+
 void MessagesManager::read_history_inbox(DialogId dialog_id, MessageId max_message_id, int32 unread_count,
                                          const char *source) {
   CHECK(!max_message_id.is_scheduled());
@@ -16163,7 +16194,15 @@ void MessagesManager::on_get_dialogs(FolderId folder_id, vector<tl_object_ptr<te
       }
     }
 
-    if (!G()->parameters().use_message_db || is_new) {
+    if (!G()->parameters().use_message_db || is_new || d->need_repair_unread_mention_count) {
+      if (d->need_repair_unread_mention_count) {
+        if (d->unread_mention_count != dialog->unread_mentions_count_) {
+          LOG(INFO) << "Repaired unread mention count in " << dialog_id << " from " << d->unread_mention_count << " to "
+                    << dialog->unread_mentions_count_;
+        }
+        d->need_repair_unread_mention_count = false;
+        on_dialog_updated(dialog_id, "repaired dialog unread mention count");
+      }
       if (d->unread_mention_count != dialog->unread_mentions_count_) {
         set_dialog_unread_mention_count(d, dialog->unread_mentions_count_);
         update_dialog_mention_notification_count(d);
@@ -16181,7 +16220,7 @@ void MessagesManager::on_get_dialogs(FolderId folder_id, vector<tl_object_ptr<te
       }
       if (d->unread_reaction_count != dialog->unread_reactions_count_) {
         set_dialog_unread_reaction_count(d, dialog->unread_reactions_count_);
-        // update_dialog_mention_notification_count(d);
+        // update_dialog_reaction_notification_count(d);
         send_update_chat_unread_reaction_count(d, source);
       }
     }
@@ -38180,6 +38219,9 @@ void MessagesManager::fix_new_dialog(Dialog *d, unique_ptr<Message> &&last_datab
   if (d->need_repair_unread_reaction_count) {
     repair_dialog_unread_reaction_count(d, Promise<Unit>(), "fix_new_dialog");
   }
+  if (d->need_repair_unread_mention_count) {
+    repair_dialog_unread_mention_count(d, "fix_new_dialog");
+  }
 }
 
 bool MessagesManager::add_dialog_last_database_message(Dialog *d, unique_ptr<Message> &&last_database_message) {

td/telegram/MessagesManager.h

@@ -1390,6 +1390,7 @@ class MessagesManager final : public Actor {
     bool is_available_reactions_inited = false;
     bool had_yet_unsent_message_id_overflow = false;
     bool need_repair_unread_reaction_count = false;
+    bool need_repair_unread_mention_count = false;
     bool is_translatable = false;
 
     bool increment_view_counter = false;
@@ -2272,6 +2273,8 @@ class MessagesManager final : public Actor {
 
   void repair_dialog_unread_reaction_count(Dialog *d, Promise<Unit> &&promise, const char *source);
 
+  void repair_dialog_unread_mention_count(Dialog *d, const char *source);
+
   void read_history_outbox(DialogId dialog_id, MessageId max_message_id, int32 read_date = -1);
 
   void read_history_on_server(Dialog *d, MessageId max_message_id);