From 917c9dc0137ab0b58880a8a023e3d5bf0c03f13d Mon Sep 17 00:00:00 2001
From: levlam <levlam@telegram.org>
Date: Mon, 4 Sep 2023 15:34:54 +0300
Subject: [PATCH] Add ForumTopicManager::read_forum_topic_messages.

---
 td/telegram/ForumTopicManager.cpp | 46 +++++++++++++++++++++++++++++++
 td/telegram/ForumTopicManager.h   |  3 ++
 td/telegram/MessagesManager.cpp   |  6 +++-
 3 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/td/telegram/ForumTopicManager.cpp b/td/telegram/ForumTopicManager.cpp
index 1c73036db..117d44be7 100644
--- a/td/telegram/ForumTopicManager.cpp
+++ b/td/telegram/ForumTopicManager.cpp
@@ -414,6 +414,35 @@ class GetForumTopicsQuery final : public Td::ResultHandler {
   }
 };
 
+class ReadForumTopicQuery final : public Td::ResultHandler {
+  DialogId dialog_id_;
+
+ public:
+  void send(DialogId dialog_id, MessageId top_thread_message_id, MessageId max_message_id) {
+    dialog_id_ = dialog_id;
+    auto input_peer = td_->messages_manager_->get_input_peer(dialog_id, AccessRights::Read);
+    if (input_peer == nullptr) {
+      return on_error(Status::Error(400, "Can't access the chat"));
+    }
+    send_query(G()->net_query_creator().create(
+        telegram_api::messages_readDiscussion(std::move(input_peer),
+                                              top_thread_message_id.get_server_message_id().get(),
+                                              max_message_id.get_server_message_id().get()),
+        {{dialog_id}}));
+  }
+
+  void on_result(BufferSlice packet) final {
+    auto result_ptr = fetch_result<telegram_api::messages_readDiscussion>(packet);
+    if (result_ptr.is_error()) {
+      return on_error(result_ptr.move_as_error());
+    }
+  }
+
+  void on_error(Status status) final {
+    td_->messages_manager_->on_get_dialog_error(dialog_id_, status, "ReadForumTopicQuery");
+  }
+};
+
 template <class StorerT>
 void ForumTopicManager::Topic::store(StorerT &storer) const {
   CHECK(info_ != nullptr);
@@ -538,6 +567,23 @@ void ForumTopicManager::edit_forum_topic(DialogId dialog_id, MessageId top_threa
       ->send(channel_id, top_thread_message_id, edit_title, new_title, edit_icon_custom_emoji, icon_custom_emoji_id);
 }
 
+void ForumTopicManager::read_forum_topic_messages(DialogId dialog_id, MessageId top_thread_message_id,
+                                                  MessageId last_read_inbox_message_id) {
+  CHECK(!td_->auth_manager_->is_bot());
+  auto topic = get_topic(dialog_id, top_thread_message_id);
+  if (topic == nullptr || topic->topic_ == nullptr) {
+    return;
+  }
+
+  if (topic->topic_->update_last_read_inbox_message_id(last_read_inbox_message_id, -1)) {
+    // TODO send updates
+    auto max_message_id = last_read_inbox_message_id.get_prev_server_message_id();
+    LOG(INFO) << "Send read topic history request in topic of " << top_thread_message_id << " in " << dialog_id
+              << " up to " << max_message_id;
+    td_->create_handler<ReadForumTopicQuery>()->send(dialog_id, top_thread_message_id, max_message_id);
+  }
+}
+
 void ForumTopicManager::on_update_forum_topic_unread(DialogId dialog_id, MessageId top_thread_message_id,
                                                      MessageId last_message_id, MessageId last_read_inbox_message_id,
                                                      MessageId last_read_outbox_message_id, int32 unread_count) {
diff --git a/td/telegram/ForumTopicManager.h b/td/telegram/ForumTopicManager.h
index 0eaf529b6..c414a35f9 100644
--- a/td/telegram/ForumTopicManager.h
+++ b/td/telegram/ForumTopicManager.h
@@ -87,6 +87,9 @@ class ForumTopicManager final : public Actor {
 
   void delete_all_dialog_topics(DialogId dialog_id);
 
+  void read_forum_topic_messages(DialogId dialog_id, MessageId top_thread_message_id,
+                                 MessageId last_read_inbox_message_id);
+
   void on_update_forum_topic_unread(DialogId dialog_id, MessageId top_thread_message_id, MessageId last_message_id,
                                     MessageId last_read_inbox_message_id, MessageId last_read_outbox_message_id,
                                     int32 unread_count);
diff --git a/td/telegram/MessagesManager.cpp b/td/telegram/MessagesManager.cpp
index b615b442f..150e12465 100644
--- a/td/telegram/MessagesManager.cpp
+++ b/td/telegram/MessagesManager.cpp
@@ -20268,7 +20268,11 @@ Status MessagesManager::view_messages(DialogId dialog_id, vector<MessageId> mess
     return Status::OK();
   }
   if (source == MessageSource::ForumTopicHistory) {
-    // TODO read forum topic history
+    if (!forum_topic_id.is_valid() || !max_message_id.is_valid()) {
+      return Status::OK();
+    }
+
+    td_->forum_topic_manager_->read_forum_topic_messages(dialog_id, forum_topic_id, max_message_id);
     return Status::OK();
   }