From 388fe6adfb203f55fee0215819e660b0d15e870f Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Tue, 20 Sep 2022 22:12:30 +0400
Subject: [PATCH] Allow enabling forum, creating topics.

---
 Telegram/CMakeLists.txt                       |   2 +
 Telegram/SourceFiles/data/data_channel.cpp    |   8 +-
 Telegram/SourceFiles/data/data_channel.h      |   2 +-
 Telegram/SourceFiles/data/data_folder.cpp     |   6 +-
 Telegram/SourceFiles/data/data_folder.h       |   8 +-
 Telegram/SourceFiles/data/data_forum.cpp      | 166 ++++++++-
 Telegram/SourceFiles/data/data_forum.h        |  36 +-
 .../SourceFiles/data/data_forum_topic.cpp     | 340 ++++++++++++++++++
 Telegram/SourceFiles/data/data_forum_topic.h  | 115 ++++++
 Telegram/SourceFiles/data/data_session.cpp    |   5 +
 Telegram/SourceFiles/data/data_types.h        |  31 +-
 .../SourceFiles/dialogs/dialogs_entry.cpp     |  20 +-
 Telegram/SourceFiles/dialogs/dialogs_entry.h  |   7 +-
 .../dialogs/dialogs_inner_widget.cpp          |  34 +-
 .../dialogs/dialogs_inner_widget.h            |   5 +-
 Telegram/SourceFiles/dialogs/dialogs_key.cpp  |  12 +
 Telegram/SourceFiles/dialogs/dialogs_key.h    |   4 +
 .../SourceFiles/dialogs/dialogs_widget.cpp    |  10 +-
 Telegram/SourceFiles/history/history.cpp      |  13 +-
 Telegram/SourceFiles/history/history_item.cpp |   3 +-
 Telegram/SourceFiles/history/history_item.h   |   3 +
 21 files changed, 781 insertions(+), 49 deletions(-)
 create mode 100644 Telegram/SourceFiles/data/data_forum_topic.cpp
 create mode 100644 Telegram/SourceFiles/data/data_forum_topic.h

diff --git a/Telegram/CMakeLists.txt b/Telegram/CMakeLists.txt
index f6952c4b9a..6e38a09d5e 100644
--- a/Telegram/CMakeLists.txt
+++ b/Telegram/CMakeLists.txt
@@ -469,6 +469,8 @@ PRIVATE
     data/data_folder.h
     data/data_forum.cpp
     data/data_forum.h
+    data/data_forum_topic.cpp
+    data/data_forum_topic.h
     data/data_file_click_handler.cpp
     data/data_file_click_handler.h
     data/data_file_origin.cpp
diff --git a/Telegram/SourceFiles/data/data_channel.cpp b/Telegram/SourceFiles/data/data_channel.cpp
index 0cbebc4286..14903e079d 100644
--- a/Telegram/SourceFiles/data/data_channel.cpp
+++ b/Telegram/SourceFiles/data/data_channel.cpp
@@ -60,11 +60,11 @@ Data::ChatBotCommands::Changed MegagroupInfo::setBotCommands(
 	return _botCommands.update(list);
 }
 
-void MegagroupInfo::setIsForum(bool is) {
+void MegagroupInfo::setIsForum(not_null<ChannelData*> that, bool is) {
 	if (is == (_forum != nullptr)) {
 		return;
 	} else if (is) {
-		_forum = std::make_unique<Data::Forum>();
+		_forum = std::make_unique<Data::Forum>(that->owner().history(that));
 	} else {
 		_forum = nullptr;
 	}
@@ -97,10 +97,6 @@ ChannelData::ChannelData(not_null<Data::Session*> owner, PeerId id)
 				mgInfo = nullptr;
 			}
 		}
-		if (change.diff & Flag::Forum) {
-			Assert(mgInfo != nullptr);
-			mgInfo->setIsForum(change.value & Flag::Forum);
-		}
 		if (change.diff & Flag::CallNotEmpty) {
 			if (const auto history = this->owner().historyLoaded(this)) {
 				history->updateChatListEntry();
diff --git a/Telegram/SourceFiles/data/data_channel.h b/Telegram/SourceFiles/data/data_channel.h
index 99f68bf272..6aa6210b64 100644
--- a/Telegram/SourceFiles/data/data_channel.h
+++ b/Telegram/SourceFiles/data/data_channel.h
@@ -100,7 +100,7 @@ public:
 		return _botCommands;
 	}
 
-	void setIsForum(bool is);
+	void setIsForum(not_null<ChannelData*> that, bool is);
 	[[nodiscard]] Data::Forum *forum() const;
 
 	std::deque<not_null<UserData*>> lastParticipants;
diff --git a/Telegram/SourceFiles/data/data_folder.cpp b/Telegram/SourceFiles/data/data_folder.cpp
index 4c5e4016aa..0c9aa0fb78 100644
--- a/Telegram/SourceFiles/data/data_folder.cpp
+++ b/Telegram/SourceFiles/data/data_folder.cpp
@@ -41,8 +41,7 @@ Folder::Folder(not_null<Data::Session*> owner, FolderId id)
 	&owner->session(),
 	FilterId(),
 	owner->maxPinnedChatsLimitValue(this, FilterId()))
-, _name(tr::lng_archived_name(tr::now))
-, _chatListNameSortKey(owner->nameSortKey(_name)) {
+, _name(tr::lng_archived_name(tr::now)) {
 	indexNameParts();
 
 	session().changes().peerUpdates(
@@ -374,7 +373,8 @@ const base::flat_set<QChar> &Folder::chatListFirstLetters() const {
 }
 
 const QString &Folder::chatListNameSortKey() const {
-	return _chatListNameSortKey;
+	static const auto empty = QString();
+	return empty;
 }
 
 } // namespace Data
diff --git a/Telegram/SourceFiles/data/data_folder.h b/Telegram/SourceFiles/data/data_folder.h
index a79e8b8ed2..c589dd762b 100644
--- a/Telegram/SourceFiles/data/data_folder.h
+++ b/Telegram/SourceFiles/data/data_folder.h
@@ -21,7 +21,6 @@ class Session;
 namespace Data {
 
 class Session;
-class Folder;
 
 class Folder final : public Dialogs::Entry, public base::has_weak_ptr {
 public:
@@ -31,12 +30,12 @@ public:
 	Folder(const Folder &) = delete;
 	Folder &operator=(const Folder &) = delete;
 
-	FolderId id() const;
+	[[nodiscard]] FolderId id() const;
 	void registerOne(not_null<History*> history);
 	void unregisterOne(not_null<History*> history);
 	void oneListMessageChanged(HistoryItem *from, HistoryItem *to);
 
-	not_null<Dialogs::MainList*> chatsList();
+	[[nodiscard]] not_null<Dialogs::MainList*> chatsList();
 
 	void applyDialog(const MTPDdialogFolder &data);
 	void applyPinnedUpdate(const MTPDupdateDialogPinned &data);
@@ -94,13 +93,12 @@ private:
 		const style::color *overrideBg,
 		const style::color *overrideFg) const;
 
-	FolderId _id = 0;
+	const FolderId _id = 0;
 	Dialogs::MainList _chatsList;
 
 	QString _name;
 	base::flat_set<QString> _nameWords;
 	base::flat_set<QChar> _nameFirstLetters;
-	QString _chatListNameSortKey;
 
 	std::vector<not_null<History*>> _lastHistories;
 	HistoryItem *_chatListMessage = nullptr;
diff --git a/Telegram/SourceFiles/data/data_forum.cpp b/Telegram/SourceFiles/data/data_forum.cpp
index 527f63112c..225ace2006 100644
--- a/Telegram/SourceFiles/data/data_forum.cpp
+++ b/Telegram/SourceFiles/data/data_forum.cpp
@@ -7,10 +7,172 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #include "data/data_forum.h"
 
-namespace Data {
+#include "data/data_channel.h"
+#include "data/data_session.h"
+#include "data/data_forum_topic.h"
+#include "history/history.h"
+#include "history/history_item.h"
+#include "main/main_session.h"
+#include "base/random.h"
+#include "apiwrap.h"
+#include "lang/lang_keys.h"
+#include "ui/layers/generic_box.h"
+#include "ui/widgets/input_fields.h"
+#include "window/window_session_controller.h"
+#include "styles/style_boxes.h"
 
-Forum::Forum() = default;
+namespace Data {
+namespace {
+
+constexpr auto kTopicsFirstLoad = 20;
+constexpr auto kTopicsPerPage = 500;
+
+} // namespace
+
+Forum::Forum(not_null<History*> forum)
+: _forum(forum)
+, _topicsList(&forum->session(), FilterId(0), rpl::single(1)) {
+}
 
 Forum::~Forum() = default;
 
+not_null<Dialogs::MainList*> Forum::topicsList() {
+	return &_topicsList;
+}
+
+void Forum::requestTopics() {
+	if (_allLoaded || _requestId) {
+		return;
+	}
+	const auto forum = _forum;
+	const auto firstLoad = !_offsetDate;
+	const auto loadCount = firstLoad ? kTopicsFirstLoad : kTopicsPerPage;
+	const auto api = &forum->session().api();
+	_requestId = api->request(MTPchannels_GetForumTopics(
+		MTP_flags(0),
+		forum->peer->asChannel()->inputChannel,
+		MTPstring(), // q
+		MTP_int(_offsetDate),
+		MTP_int(_offsetId),
+		MTP_int(_offsetTopicId),
+		MTP_int(loadCount)
+	)).done([=](const MTPmessages_ForumTopics &result) {
+		if (!forum->peer->isForum()) {
+			return;
+		}
+		const auto &data = result.data();
+		const auto owner = &forum->owner();
+		owner->processUsers(data.vusers());
+		owner->processChats(data.vchats());
+		owner->processMessages(data.vmessages(), NewMessageType::Existing);
+		forum->peer->asChannel()->ptsReceived(data.vpts().v);
+		const auto &list = data.vtopics().v;
+		for (const auto &topic : list) {
+			const auto rootId = MsgId(topic.data().vid().v);
+			if (const auto i = _topics.find(rootId); i != end(_topics)) {
+				i->second->applyTopic(topic);
+			} else {
+				const auto raw = _topics.emplace(
+					rootId,
+					std::make_unique<ForumTopic>(forum, rootId)
+				).first->second.get();
+				raw->applyTopic(topic);
+				raw->addToChatList(FilterId(), topicsList());
+			}
+		}
+		if (list.isEmpty() || list.size() == data.vcount().v) {
+			_allLoaded = true;
+		}
+		if (const auto date = data.vnext_date()) {
+			_offsetDate = date->v;
+		}
+		_requestId = 0;
+		_chatsListChanges.fire({});
+		if (_allLoaded) {
+			_chatsListLoadedEvents.fire({});
+		}
+	}).fail([=](const MTP::Error &error) {
+		_allLoaded = true;
+		_requestId = 0;
+	}).send();
+}
+
+void Forum::topicAdded(not_null<HistoryItem*> root) {
+	const auto rootId = root->id;
+	if (const auto i = _topics.find(rootId); i != end(_topics)) {
+		//i->second->applyTopic(topic);
+	} else {
+		const auto raw = _topics.emplace(
+			rootId,
+			std::make_unique<ForumTopic>(_forum, rootId)
+		).first->second.get();
+		//raw->applyTopic(topic);
+		raw->addToChatList(FilterId(), topicsList());
+		_chatsListChanges.fire({});
+	}
+}
+
+rpl::producer<> Forum::chatsListChanges() const {
+	return _chatsListChanges.events();
+}
+
+rpl::producer<> Forum::chatsListLoadedEvents() const {
+	return _chatsListLoadedEvents.events();
+}
+
+void ShowAddForumTopic(
+		not_null<Window::SessionController*> controller,
+		not_null<ChannelData*> forum) {
+	controller->show(Box([=](not_null<Ui::GenericBox*> box) {
+		box->setTitle(rpl::single(u"New Topic"_q));
+
+		const auto title = box->addRow(
+			object_ptr<Ui::InputField>(
+				box,
+				st::defaultInputField,
+				rpl::single(u"Topic Title"_q))); // #TODO forum
+		const auto message = box->addRow(
+			object_ptr<Ui::InputField>(
+				box,
+				st::newGroupDescription,
+				Ui::InputField::Mode::MultiLine,
+				rpl::single(u"Message"_q))); // #TODO forum
+		box->setFocusCallback([=] {
+			title->setFocusFast();
+		});
+		box->addButton(tr::lng_create_group_create(), [=] {
+			if (!forum->isForum()) {
+				box->closeBox();
+				return;
+			} else if (title->getLastText().trimmed().isEmpty()) {
+				title->setFocus();
+				return;
+			} else if (message->getLastText().trimmed().isEmpty()) {
+				message->setFocus();
+				return;
+			}
+			const auto randomId = base::RandomValue<uint64>();
+			const auto api = &forum->session().api();
+			api->request(MTPchannels_CreateForumTopic(
+				MTP_flags(0),
+				forum->inputChannel,
+				MTP_string(title->getLastText().trimmed()),
+				MTPInputMedia(),
+				MTP_string(message->getLastText().trimmed()),
+				MTP_long(randomId),
+				MTPVector<MTPMessageEntity>(),
+				MTPInputPeer() // send_as
+			)).done([=](const MTPUpdates &result) {
+				api->applyUpdates(result, randomId);
+				box->closeBox();
+			}).fail([=](const MTP::Error &error) {
+				api->sendMessageFail(error, forum, randomId);
+			}).send();
+		});
+		box->addButton(tr::lng_cancel(), [=] {
+			box->closeBox();
+		});
+	}), Ui::LayerOption::KeepOther);
+}
+
 } // namespace Data
diff --git a/Telegram/SourceFiles/data/data_forum.h b/Telegram/SourceFiles/data/data_forum.h
index 437e87f42d..51fc36230b 100644
--- a/Telegram/SourceFiles/data/data_forum.h
+++ b/Telegram/SourceFiles/data/data_forum.h
@@ -7,15 +7,49 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #pragma once
 
+#include "dialogs/dialogs_main_list.h"
+
+class History;
+class ChannelData;
+
+namespace Window {
+class SessionController;
+} // namespace Window;
+
 namespace Data {
 
 class Forum final {
 public:
-	Forum();
+	explicit Forum(not_null<History*> forum);
 	~Forum();
 
+	[[nodiscard]] not_null<Dialogs::MainList*> topicsList();
+
+	void requestTopics();
+	[[nodiscard]] rpl::producer<> chatsListChanges() const;
+	[[nodiscard]] rpl::producer<> chatsListLoadedEvents() const;
+
+	void topicAdded(not_null<HistoryItem*> root);
+
 private:
+	const not_null<History*> _forum;
+
+	base::flat_map<MsgId, std::unique_ptr<ForumTopic>> _topics;
+	Dialogs::MainList _topicsList;
+
+	mtpRequestId _requestId = 0;
+	TimeId _offsetDate = 0;
+	MsgId _offsetId = 0;
+	MsgId _offsetTopicId = 0;
+	bool _allLoaded = false;
+
+	rpl::event_stream<> _chatsListChanges;
+	rpl::event_stream<> _chatsListLoadedEvents;
 
 };
 
+void ShowAddForumTopic(
+	not_null<Window::SessionController*> controller,
+	not_null<ChannelData*> forum);
+
 } // namespace Data
diff --git a/Telegram/SourceFiles/data/data_forum_topic.cpp b/Telegram/SourceFiles/data/data_forum_topic.cpp
new file mode 100644
index 0000000000..8970669334
--- /dev/null
+++ b/Telegram/SourceFiles/data/data_forum_topic.cpp
@@ -0,0 +1,340 @@
+/*
+This file is part of Telegram Desktop,
+the official desktop application for the Telegram messaging service.
+
+For license and copyright information please follow this link:
+https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
+*/
+#include "data/data_forum_topic.h"
+
+#include "data/data_channel.h"
+#include "data/data_forum.h"
+#include "data/data_session.h"
+#include "dialogs/dialogs_main_list.h"
+#include "core/application.h"
+#include "core/core_settings.h"
+#include "history/history.h"
+#include "history/history_item.h"
+
+namespace Data {
+
+ForumTopic::ForumTopic(not_null<History*> forum, MsgId rootId)
+: Entry(&forum->owner(), Type::ForumTopic)
+, _forum(forum)
+, _list(forum->peer->asChannel()->forum()->topicsList())
+, _rootId(rootId) {
+}
+
+not_null<History*> ForumTopic::forum() const {
+	return _forum;
+}
+
+MsgId ForumTopic::rootId() const {
+	return _rootId;
+}
+
+void ForumTopic::applyTopic(const MTPForumTopic &topic) {
+	Expects(_rootId == topic.data().vid().v);
+
+	const auto &data = topic.data();
+	const auto title = qs(data.vtitle());
+	if (_title != title) {
+		_title = title;
+		++_titleVersion;
+		indexTitleParts();
+		updateChatListEntry();
+	}
+
+	const auto pinned = _list->pinned();
+	if (data.is_pinned()) {
+		pinned->addPinned(Dialogs::Key(this));
+	} else {
+		pinned->setPinned(Dialogs::Key(this), false);
+	}
+
+	applyTopicFields(
+		data.vunread_count().v,
+		data.vread_inbox_max_id().v,
+		data.vread_outbox_max_id().v);
+	applyTopicTopMessage(data.vtop_message().v);
+	//setUnreadMark(data.is_unread_mark());
+}
+
+void ForumTopic::indexTitleParts() {
+	_titleWords.clear();
+	_titleFirstLetters.clear();
+	auto toIndexList = QStringList();
+	auto appendToIndex = [&](const QString &value) {
+		if (!value.isEmpty()) {
+			toIndexList.push_back(TextUtilities::RemoveAccents(value));
+		}
+	};
+
+	appendToIndex(_title);
+	const auto appendTranslit = !toIndexList.isEmpty()
+		&& cRussianLetters().match(toIndexList.front()).hasMatch();
+	if (appendTranslit) {
+		appendToIndex(translitRusEng(toIndexList.front()));
+	}
+	auto toIndex = toIndexList.join(' ');
+	toIndex += ' ' + rusKeyboardLayoutSwitch(toIndex);
+
+	const auto namesList = TextUtilities::PrepareSearchWords(toIndex);
+	for (const auto &name : namesList) {
+		_titleWords.insert(name);
+		_titleFirstLetters.insert(name[0]);
+	}
+}
+
+int ForumTopic::chatListNameVersion() const {
+	return _titleVersion;
+}
+
+void ForumTopic::applyTopicFields(
+		int unreadCount,
+		MsgId maxInboxRead,
+		MsgId maxOutboxRead) {
+	if (maxInboxRead + 1 >= _inboxReadBefore.value_or(1)) {
+		setUnreadCount(unreadCount);
+		setInboxReadTill(maxInboxRead);
+	}
+	setOutboxReadTill(maxOutboxRead);
+}
+
+void ForumTopic::applyTopicTopMessage(MsgId topMessageId) {
+	if (topMessageId) {
+		const auto itemId = FullMsgId(_forum->peer->id, topMessageId);
+		if (const auto item = owner().message(itemId)) {
+			setLastServerMessage(item);
+		} else {
+			setLastServerMessage(nullptr);
+		}
+	} else {
+		setLastServerMessage(nullptr);
+	}
+}
+
+void ForumTopic::setLastServerMessage(HistoryItem *item) {
+	_lastServerMessage = item;
+	if (_lastMessage
+		&& *_lastMessage
+		&& !(*_lastMessage)->isRegular()
+		&& (!item || (*_lastMessage)->date() > item->date())) {
+		return;
+	}
+	setLastMessage(item);
+}
+
+void ForumTopic::setLastMessage(HistoryItem *item) {
+	if (_lastMessage && *_lastMessage == item) {
+		return;
+	}
+	_lastMessage = item;
+	if (!item || item->isRegular()) {
+		_lastServerMessage = item;
+	}
+	setChatListMessage(item);
+}
+
+void ForumTopic::setChatListMessage(HistoryItem *item) {
+	if (_chatListMessage && *_chatListMessage == item) {
+		return;
+	}
+	const auto was = _chatListMessage.value_or(nullptr);
+	if (item) {
+		if (item->isSponsored()) {
+			return;
+		}
+		if (_chatListMessage
+			&& *_chatListMessage
+			&& !(*_chatListMessage)->isRegular()
+			&& (*_chatListMessage)->date() > item->date()) {
+			return;
+		}
+		_chatListMessage = item;
+		setChatListTimeId(item->date());
+
+#if 0 // #TODO forum
+		// If we have a single message from a group, request the full album.
+		if (hasOrphanMediaGroupPart()
+			&& !item->toPreview({
+				.hideSender = true,
+				.hideCaption = true }).images.empty()) {
+			owner().histories().requestGroupAround(item);
+		}
+#endif
+	} else if (!_chatListMessage || *_chatListMessage) {
+		_chatListMessage = nullptr;
+		updateChatListEntry();
+	}
+}
+
+void ForumTopic::setInboxReadTill(MsgId upTo) {
+	if (_inboxReadBefore) {
+		accumulate_max(*_inboxReadBefore, upTo + 1);
+	} else {
+		_inboxReadBefore = upTo + 1;
+	}
+}
+
+void ForumTopic::setOutboxReadTill(MsgId upTo) {
+	if (_outboxReadBefore) {
+		accumulate_max(*_outboxReadBefore, upTo + 1);
+	} else {
+		_outboxReadBefore = upTo + 1;
+	}
+}
+
+void ForumTopic::loadUserpic() {
+}
+
+void ForumTopic::paintUserpic(
+		Painter &p,
+		std::shared_ptr<Data::CloudImageView> &view,
+		int x,
+		int y,
+		int size) const {
+	// #TODO forum
+}
+
+void ForumTopic::requestChatListMessage() {
+	if (!chatListMessageKnown()) {
+		// #TODO forum
+	}
+}
+
+TimeId ForumTopic::adjustedChatListTimeId() const {
+	const auto result = chatListTimeId();
+#if 0 // #TODO forum
+	if (const auto draft = cloudDraft()) {
+		if (!Data::draftIsNull(draft) && !session().supportMode()) {
+			return std::max(result, draft->date);
+		}
+	}
+#endif
+	return result;
+}
+
+int ForumTopic::fixedOnTopIndex() const {
+	return kArchiveFixOnTopIndex;
+}
+
+bool ForumTopic::shouldBeInChatList() const {
+	return isPinnedDialog(FilterId())
+		|| !lastMessageKnown()
+		|| (lastMessage() != nullptr);
+}
+
+HistoryItem *ForumTopic::lastMessage() const {
+	return _lastMessage.value_or(nullptr);
+}
+
+bool ForumTopic::lastMessageKnown() const {
+	return _lastMessage.has_value();
+}
+
+HistoryItem *ForumTopic::lastServerMessage() const {
+	return _lastServerMessage.value_or(nullptr);
+}
+
+bool ForumTopic::lastServerMessageKnown() const {
+	return _lastServerMessage.has_value();
+}
+
+int ForumTopic::unreadCount() const {
+	return _unreadCount ? *_unreadCount : 0;
+}
+
+int ForumTopic::unreadCountForBadge() const {
+	const auto result = unreadCount();
+	return (!result && unreadMark()) ? 1 : result;
+}
+
+bool ForumTopic::unreadCountKnown() const {
+	return _unreadCount.has_value();
+}
+
+void ForumTopic::setUnreadCount(int newUnreadCount) {
+	if (_unreadCount == newUnreadCount) {
+		return;
+	}
+	const auto wasForBadge = (unreadCountForBadge() > 0);
+	const auto notifier = unreadStateChangeNotifier(true);
+	_unreadCount = newUnreadCount;
+}
+
+void ForumTopic::setUnreadMark(bool unread) {
+	if (_unreadMark == unread) {
+		return;
+	}
+	const auto noUnreadMessages = !unreadCount();
+	const auto refresher = gsl::finally([&] {
+		if (inChatList() && noUnreadMessages) {
+			updateChatListEntry();
+		}
+	});
+	const auto notifier = unreadStateChangeNotifier(noUnreadMessages);
+	_unreadMark = unread;
+}
+
+bool ForumTopic::unreadMark() const {
+	return _unreadMark;
+}
+
+int ForumTopic::chatListUnreadCount() const {
+	const auto state = chatListUnreadState();
+	return state.marks
+		+ (Core::App().settings().countUnreadMessages()
+			? state.messages
+			: state.chats);
+}
+
+Dialogs::UnreadState ForumTopic::chatListUnreadState() const {
+	auto result = Dialogs::UnreadState();
+	const auto count = _unreadCount.value_or(0);
+	const auto mark = !count && _unreadMark;
+	const auto muted = _forum->mute();
+	result.messages = count;
+	result.messagesMuted = muted ? count : 0;
+	result.chats = count ? 1 : 0;
+	result.chatsMuted = (count && muted) ? 1 : 0;
+	result.marks = mark ? 1 : 0;
+	result.marksMuted = (mark && muted) ? 1 : 0;
+	result.known = _unreadCount.has_value();
+	return result;
+}
+
+bool ForumTopic::chatListUnreadMark() const {
+	return false;
+}
+
+bool ForumTopic::chatListMutedBadge() const {
+	return true;
+}
+
+HistoryItem *ForumTopic::chatListMessage() const {
+	return _lastMessage.value_or(nullptr);
+}
+
+bool ForumTopic::chatListMessageKnown() const {
+	return _lastMessage.has_value();
+}
+
+const QString &ForumTopic::chatListName() const {
+	return _title;
+}
+
+const base::flat_set<QString> &ForumTopic::chatListNameWords() const {
+	return _titleWords;
+}
+
+const base::flat_set<QChar> &ForumTopic::chatListFirstLetters() const {
+	return _titleFirstLetters;
+}
+
+const QString &ForumTopic::chatListNameSortKey() const {
+	static const auto empty = QString();
+	return empty;
+}
+
+} // namespace Data
diff --git a/Telegram/SourceFiles/data/data_forum_topic.h b/Telegram/SourceFiles/data/data_forum_topic.h
new file mode 100644
index 0000000000..844dbd14e1
--- /dev/null
+++ b/Telegram/SourceFiles/data/data_forum_topic.h
@@ -0,0 +1,115 @@
+/*
+This file is part of Telegram Desktop,
+the official desktop application for the Telegram messaging service.
+
+For license and copyright information please follow this link:
+https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
+*/
+#pragma once
+
+#include "dialogs/dialogs_entry.h"
+
+class ChannelData;
+
+namespace Dialogs {
+class MainList;
+} // namespace Dialogs
+
+namespace Main {
+class Session;
+} // namespace Main
+
+namespace Data {
+
+class Session;
+
+class ForumTopic final : public Dialogs::Entry {
+public:
+	ForumTopic(not_null<History*> forum, MsgId rootId);
+
+	ForumTopic(const ForumTopic &) = delete;
+	ForumTopic &operator=(const ForumTopic &) = delete;
+
+	[[nodiscard]] not_null<History*> forum() const;
+	[[nodiscard]] MsgId rootId() const;
+
+	void applyTopic(const MTPForumTopic &topic);
+
+	TimeId adjustedChatListTimeId() const override;
+
+	int fixedOnTopIndex() const override;
+	bool shouldBeInChatList() const override;
+	int chatListUnreadCount() const override;
+	bool chatListUnreadMark() const override;
+	bool chatListMutedBadge() const override;
+	Dialogs::UnreadState chatListUnreadState() const override;
+	HistoryItem *chatListMessage() const override;
+	bool chatListMessageKnown() const override;
+	void requestChatListMessage() override;
+	const QString &chatListName() const override;
+	const QString &chatListNameSortKey() const override;
+	const base::flat_set<QString> &chatListNameWords() const override;
+	const base::flat_set<QChar> &chatListFirstLetters() const override;
+
+	[[nodiscard]] HistoryItem *lastMessage() const;
+	[[nodiscard]] HistoryItem *lastServerMessage() const;
+	[[nodiscard]] bool lastMessageKnown() const;
+	[[nodiscard]] bool lastServerMessageKnown() const;
+
+	void loadUserpic() override;
+	void paintUserpic(
+		Painter &p,
+		std::shared_ptr<Data::CloudImageView> &view,
+		int x,
+		int y,
+		int size) const override;
+
+	[[nodiscard]] int unreadCount() const;
+	[[nodiscard]] bool unreadCountKnown() const;
+
+	[[nodiscard]] int unreadCountForBadge() const; // unreadCount || unreadMark ? 1 : 0.
+
+	void setUnreadCount(int newUnreadCount);
+	void setUnreadMark(bool unread);
+	[[nodiscard]] bool unreadMark() const;
+
+private:
+	void indexTitleParts();
+	void applyTopicTopMessage(MsgId topMessageId);
+	void applyTopicFields(
+		int unreadCount,
+		MsgId maxInboxRead,
+		MsgId maxOutboxRead);
+	void applyChatListMessage(HistoryItem *item);
+
+	void setLastMessage(HistoryItem *item);
+	void setLastServerMessage(HistoryItem *item);
+	void setChatListMessage(HistoryItem *item);
+
+	void setInboxReadTill(MsgId upTo);
+	void setOutboxReadTill(MsgId upTo);
+
+	int chatListNameVersion() const override;
+
+	const not_null<History*> _forum;
+	const not_null<Dialogs::MainList*> _list;
+	const MsgId _rootId = 0;
+
+	QString _title;
+	base::flat_set<QString> _titleWords;
+	base::flat_set<QChar> _titleFirstLetters;
+	int _titleVersion = 0;
+
+	std::optional<MsgId> _inboxReadBefore;
+	std::optional<MsgId> _outboxReadBefore;
+	std::optional<int> _unreadCount;
+	std::optional<HistoryItem*> _lastMessage;
+	std::optional<HistoryItem*> _lastServerMessage;
+	std::optional<HistoryItem*> _chatListMessage;
+	bool _unreadMark = false;
+
+	rpl::lifetime _lifetime;
+
+};
+
+} // namespace Data
diff --git a/Telegram/SourceFiles/data/data_session.cpp b/Telegram/SourceFiles/data/data_session.cpp
index ccea61bf5b..4651f4b8b1 100644
--- a/Telegram/SourceFiles/data/data_session.cpp
+++ b/Telegram/SourceFiles/data/data_session.cpp
@@ -805,7 +805,12 @@ not_null<PeerData*> Session::processChat(const MTPChat &data) {
 			| ((data.is_forum() && data.is_megagroup())
 				? Flag::Forum
 				: Flag());
+		const auto wasForum = channel->isForum();
 		channel->setFlags((channel->flags() & ~flagsMask) | flagsSet);
+		if (const auto nowForum = channel->isForum(); nowForum != wasForum) {
+			Assert(channel->mgInfo != nullptr);
+			channel->mgInfo->setIsForum(channel, nowForum);
+		}
 
 		channel->setName(
 			qs(data.vtitle()),
diff --git a/Telegram/SourceFiles/data/data_types.h b/Telegram/SourceFiles/data/data_types.h
index 3896ad2c6a..43c06cab85 100644
--- a/Telegram/SourceFiles/data/data_types.h
+++ b/Telegram/SourceFiles/data/data_types.h
@@ -239,52 +239,53 @@ enum class MessageFlag : uint64 {
 	MentionsMe            = (1ULL << 15),
 	IsOrWasScheduled      = (1ULL << 16),
 	NoForwards            = (1ULL << 17),
+	TopicStart            = (1ULL << 18),
 
 	// Needs to return back to inline mode.
-	HasSwitchInlineButton = (1ULL << 18),
+	HasSwitchInlineButton = (1ULL << 19),
 
 	// For "shared links" indexing.
-	HasTextLinks          = (1ULL << 19),
+	HasTextLinks          = (1ULL << 20),
 
 	// Group / channel create or migrate service message.
-	IsGroupEssential      = (1ULL << 20),
+	IsGroupEssential      = (1ULL << 21),
 
 	// Edited media is generated on the client
 	// and should not update media from server.
-	IsLocalUpdateMedia    = (1ULL << 21),
+	IsLocalUpdateMedia    = (1ULL << 22),
 
 	// Sent from inline bot, need to re-set media when sent.
-	FromInlineBot         = (1ULL << 22),
+	FromInlineBot         = (1ULL << 23),
 
 	// Generated on the client side and should be unread.
-	ClientSideUnread      = (1ULL << 23),
+	ClientSideUnread      = (1ULL << 24),
 
 	// In a supergroup.
-	HasAdminBadge         = (1ULL << 24),
+	HasAdminBadge         = (1ULL << 25),
 
 	// Outgoing message that is being sent.
-	BeingSent             = (1ULL << 25),
+	BeingSent             = (1ULL << 26),
 
 	// Outgoing message and failed to be sent.
-	SendingFailed         = (1ULL << 26),
+	SendingFailed         = (1ULL << 27),
 
 	// No media and only a several emoji or an only custom emoji text.
-	SpecialOnlyEmoji      = (1ULL << 27),
+	SpecialOnlyEmoji      = (1ULL << 28),
 
 	// Message existing in the message history.
-	HistoryEntry          = (1ULL << 28),
+	HistoryEntry          = (1ULL << 29),
 
 	// Local message, not existing on the server.
-	Local                 = (1ULL << 29),
+	Local                 = (1ULL << 30),
 
 	// Fake message for some UI element.
-	FakeHistoryItem       = (1ULL << 30),
+	FakeHistoryItem       = (1ULL << 31),
 
 	// Contact sign-up message, notification should be skipped for Silent.
-	IsContactSignUp       = (1ULL << 31),
+	IsContactSignUp       = (1ULL << 32),
 
 	// Optimization for item text custom emoji repainting.
-	CustomEmojiRepainting = (1ULL << 32),
+	CustomEmojiRepainting = (1ULL << 33),
 };
 inline constexpr bool is_flag_type(MessageFlag) { return true; }
 using MessageFlags = base::flags<MessageFlag>;
diff --git a/Telegram/SourceFiles/dialogs/dialogs_entry.cpp b/Telegram/SourceFiles/dialogs/dialogs_entry.cpp
index 2c85eb42fc..cea7af9ec1 100644
--- a/Telegram/SourceFiles/dialogs/dialogs_entry.cpp
+++ b/Telegram/SourceFiles/dialogs/dialogs_entry.cpp
@@ -12,6 +12,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_changes.h"
 #include "data/data_session.h"
 #include "data/data_folder.h"
+#include "data/data_forum_topic.h"
 #include "data/data_chat_filters.h"
 #include "mainwidget.h"
 #include "main/main_session.h"
@@ -45,7 +46,7 @@ uint64 PinnedDialogPos(int pinnedIndex) {
 
 Entry::Entry(not_null<Data::Session*> owner, Type type)
 : _owner(owner)
-, _isFolder(type == Type::Folder) {
+, _type(type) {
 }
 
 Data::Session &Entry::owner() const {
@@ -57,11 +58,19 @@ Main::Session &Entry::session() const {
 }
 
 History *Entry::asHistory() {
-	return _isFolder ? nullptr : static_cast<History*>(this);
+	return (_type == Type::History) ? static_cast<History*>(this) : nullptr;
 }
 
 Data::Folder *Entry::asFolder() {
-	return _isFolder ? static_cast<Data::Folder*>(this) : nullptr;
+	return (_type == Type::Folder)
+		? static_cast<Data::Folder*>(this)
+		: nullptr;
+}
+
+Data::ForumTopic *Entry::asForumTopic() {
+	return (_type == Type::ForumTopic)
+		? static_cast<Data::ForumTopic*>(this)
+		: nullptr;
 }
 
 void Entry::pinnedIndexChanged(FilterId filterId, int was, int now) {
@@ -177,6 +186,9 @@ const Ui::Text::String &Entry::chatListNameText() const {
 }
 
 void Entry::setChatListExistence(bool exists) {
+	if (asForumTopic()) {
+		return;
+	}
 	if (exists && _sortKeyInChatList) {
 		owner().refreshChatListEntry(this);
 		updateChatListEntry();
@@ -251,7 +263,7 @@ not_null<Row*> Entry::addToChatList(
 void Entry::removeFromChatList(
 		FilterId filterId,
 		not_null<MainList*> list) {
-	if (isPinnedDialog(filterId)) {
+	if (!asForumTopic() && isPinnedDialog(filterId)) {
 		owner().setChatPinned(this, filterId, false);
 	}
 
diff --git a/Telegram/SourceFiles/dialogs/dialogs_entry.h b/Telegram/SourceFiles/dialogs/dialogs_entry.h
index 9706376350..d18c5a2381 100644
--- a/Telegram/SourceFiles/dialogs/dialogs_entry.h
+++ b/Telegram/SourceFiles/dialogs/dialogs_entry.h
@@ -19,6 +19,7 @@ class Session;
 namespace Data {
 class Session;
 class Folder;
+class ForumTopic;
 class CloudImageView;
 } // namespace Data
 
@@ -91,9 +92,10 @@ inline UnreadState operator-(const UnreadState &a, const UnreadState &b) {
 
 class Entry {
 public:
-	enum class Type {
+	enum class Type : uchar {
 		History,
 		Folder,
+		ForumTopic,
 	};
 	Entry(not_null<Data::Session*> owner, Type type);
 	Entry(const Entry &other) = delete;
@@ -105,6 +107,7 @@ public:
 
 	History *asHistory();
 	Data::Folder *asFolder();
+	Data::ForumTopic *asForumTopic();
 
 	PositionChange adjustByPosInChatList(
 		FilterId filterId,
@@ -230,7 +233,7 @@ private:
 	mutable int _chatListNameVersion = 0;
 	TimeId _timeId = 0;
 	bool _isTopPromoted = false;
-	const bool _isFolder = false;
+	const Type _type;
 
 };
 
diff --git a/Telegram/SourceFiles/dialogs/dialogs_inner_widget.cpp b/Telegram/SourceFiles/dialogs/dialogs_inner_widget.cpp
index d677a81d81..0b6b665fc3 100644
--- a/Telegram/SourceFiles/dialogs/dialogs_inner_widget.cpp
+++ b/Telegram/SourceFiles/dialogs/dialogs_inner_widget.cpp
@@ -24,6 +24,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "ui/ui_utility.h"
 #include "data/data_drafts.h"
 #include "data/data_folder.h"
+#include "data/data_forum.h"
 #include "data/data_session.h"
 #include "data/data_channel.h"
 #include "data/data_chat.h"
@@ -409,6 +410,17 @@ void InnerWidget::changeOpenedForum(ChannelData *forum) {
 	stopReorderPinned();
 	clearSelection();
 	_openedForum = forum;
+
+	_openedForumLifetime.destroy();
+	if (forum) {
+		rpl::merge(
+			forum->forum()->chatsListChanges(),
+			forum->forum()->chatsListLoadedEvents()
+		) | rpl::start_with_next([=] {
+			refresh();
+		}, _openedForumLifetime);
+	}
+
 	refreshWithCollapsedRows(true);
 	if (_loadMoreCallback) {
 		_loadMoreCallback();
@@ -1778,6 +1790,8 @@ void InnerWidget::updateSelectedRow(Key key) {
 not_null<IndexedList*> InnerWidget::shownDialogs() const {
 	return _filterId
 		? session().data().chatsFilters().chatsList(_filterId)->indexed()
+		: _openedForum
+		? _openedForum->forum()->topicsList()->indexed()
 		: session().data().chatsList(_openedFolder)->indexed();
 }
 
@@ -2346,6 +2360,8 @@ void InnerWidget::refreshEmptyLabel() {
 	const auto data = &session().data();
 	const auto state = !shownDialogs()->empty()
 		? EmptyState::None
+		: _openedForum
+		? EmptyState::EmptyForum
 		: (!_filterId && data->contactsLoaded().current())
 		? EmptyState::NoContacts
 		: (_filterId > 0) && data->chatsList()->loaded()
@@ -2364,11 +2380,17 @@ void InnerWidget::refreshEmptyLabel() {
 		? tr::lng_no_chats()
 		: (state == EmptyState::EmptyFolder)
 		? tr::lng_no_chats_filter()
+		: (state == EmptyState::EmptyForum)
+		// #TODO forum
+		? rpl::single(u"No chats currently created in this forum."_q)
 		: tr::lng_contacts_loading();
 	auto link = (state == EmptyState::NoContacts)
 		? tr::lng_add_contact_button()
 		: (state == EmptyState::EmptyFolder)
 		? tr::lng_filters_context_edit()
+		: (state == EmptyState::EmptyForum)
+		// #TODO forum
+		? rpl::single(u"Create topic"_q)
 		: rpl::single(QString());
 	auto full = rpl::combine(
 		std::move(phrase),
@@ -2387,6 +2409,8 @@ void InnerWidget::refreshEmptyLabel() {
 			_controller->showAddContact();
 		} else if (_emptyState == EmptyState::EmptyFolder) {
 			editOpenedFilter();
+		} else if (_emptyState == EmptyState::EmptyForum) {
+			Data::ShowAddForumTopic(_controller, _openedForum);
 		}
 	});
 	_empty->setVisible(_state == WidgetState::Default);
@@ -3261,9 +3285,13 @@ void InnerWidget::setupShortcuts() {
 			return jumpToDialogRow(last);
 		});
 		request->check(Command::ChatSelf) && request->handle([=] {
-			_controller->content()->choosePeer(
-				session().userPeerId(),
-				ShowAtUnreadMsgId);
+			if (_openedForum) {
+				Data::ShowAddForumTopic(_controller, _openedForum);
+			} else {
+				_controller->content()->choosePeer(
+					session().userPeerId(),
+					ShowAtUnreadMsgId);
+			}
 			return true;
 		});
 		request->check(Command::ShowArchive) && request->handle([=] {
diff --git a/Telegram/SourceFiles/dialogs/dialogs_inner_widget.h b/Telegram/SourceFiles/dialogs/dialogs_inner_widget.h
index e37fc4a325..1098952205 100644
--- a/Telegram/SourceFiles/dialogs/dialogs_inner_widget.h
+++ b/Telegram/SourceFiles/dialogs/dialogs_inner_widget.h
@@ -331,7 +331,7 @@ private:
 	void clearSearchResults(bool clearPeerSearchResults = true);
 	void updateSelectedRow(Key key = Key());
 
-	not_null<IndexedList*> shownDialogs() const;
+	[[nodiscard]] not_null<IndexedList*> shownDialogs() const;
 
 	void checkReorderPinnedStart(QPoint localPosition);
 	int updateReorderIndexGetCount();
@@ -343,7 +343,7 @@ private:
 	bool pinnedShiftAnimationCallback(crl::time now);
 	void handleChatListEntryRefreshes();
 
-	not_null<Window::SessionController*> _controller;
+	const not_null<Window::SessionController*> _controller;
 
 	FilterId _filterId = 0;
 	bool _mouseSelection = false;
@@ -352,6 +352,7 @@ private:
 
 	Data::Folder *_openedFolder = nullptr;
 	ChannelData *_openedForum = nullptr;
+	rpl::lifetime _openedForumLifetime;
 
 	std::vector<std::unique_ptr<CollapsedRow>> _collapsedRows;
 	int _collapsedSelected = -1;
diff --git a/Telegram/SourceFiles/dialogs/dialogs_key.cpp b/Telegram/SourceFiles/dialogs/dialogs_key.cpp
index a9013a29f1..0d6c570b09 100644
--- a/Telegram/SourceFiles/dialogs/dialogs_key.cpp
+++ b/Telegram/SourceFiles/dialogs/dialogs_key.cpp
@@ -8,12 +8,14 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "dialogs/dialogs_key.h"
 
 #include "data/data_folder.h"
+#include "data/data_forum_topic.h"
 #include "history/history.h"
 
 namespace Dialogs {
 namespace {
 
 using Folder = Data::Folder;
+using ForumTopic = Data::ForumTopic;
 
 } // namespace
 
@@ -23,12 +25,18 @@ Key::Key(History *history) : _value(history) {
 Key::Key(Data::Folder *folder) : _value(folder) {
 }
 
+Key::Key(Data::ForumTopic *forumTopic) : _value(forumTopic) {
+}
+
 Key::Key(not_null<History*> history) : _value(history) {
 }
 
 Key::Key(not_null<Data::Folder*> folder) : _value(folder) {
 }
 
+Key::Key(not_null<Data::ForumTopic*> forumTopic) : _value(forumTopic) {
+}
+
 not_null<Entry*> Key::entry() const {
 	Expects(_value != nullptr);
 
@@ -43,6 +51,10 @@ Folder *Key::folder() const {
 	return _value ? _value->asFolder() : nullptr;
 }
 
+ForumTopic *Key::forumTopic() const {
+	return _value ? _value->asForumTopic() : nullptr;
+}
+
 PeerData *Key::peer() const {
 	if (const auto history = this->history()) {
 		return history->peer;
diff --git a/Telegram/SourceFiles/dialogs/dialogs_key.h b/Telegram/SourceFiles/dialogs/dialogs_key.h
index 2f5967b45b..f77acc3bfc 100644
--- a/Telegram/SourceFiles/dialogs/dialogs_key.h
+++ b/Telegram/SourceFiles/dialogs/dialogs_key.h
@@ -14,6 +14,7 @@ class PeerData;
 
 namespace Data {
 class Folder;
+class ForumTopic;
 } // namespace Data
 
 namespace Dialogs {
@@ -27,10 +28,12 @@ public:
 	}
 	Key(History *history);
 	Key(Data::Folder *folder);
+	Key(Data::ForumTopic *forumTopic);
 	Key(not_null<Entry*> entry) : _value(entry) {
 	}
 	Key(not_null<History*> history);
 	Key(not_null<Data::Folder*> folder);
+	Key(not_null<Data::ForumTopic*> forumTopic);
 
 	explicit operator bool() const {
 		return (_value != nullptr);
@@ -38,6 +41,7 @@ public:
 	not_null<Entry*> entry() const;
 	History *history() const;
 	Data::Folder *folder() const;
+	Data::ForumTopic *forumTopic() const;
 	PeerData *peer() const;
 
 	inline bool operator<(const Key &other) const {
diff --git a/Telegram/SourceFiles/dialogs/dialogs_widget.cpp b/Telegram/SourceFiles/dialogs/dialogs_widget.cpp
index 9da3065040..cb53901c33 100644
--- a/Telegram/SourceFiles/dialogs/dialogs_widget.cpp
+++ b/Telegram/SourceFiles/dialogs/dialogs_widget.cpp
@@ -46,6 +46,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_chat.h"
 #include "data/data_user.h"
 #include "data/data_folder.h"
+#include "data/data_forum.h"
+#include "data/data_forum_topic.h"
 #include "data/data_histories.h"
 #include "data/data_changes.h"
 #include "data/data_download_manager.h"
@@ -261,7 +263,11 @@ Widget::Widget(
 		const auto openSearchResult = !controller->selectingPeer()
 			&& row.filteredRow;
 		const auto history = row.key.history();
-		if (history && history->peer->isForum()) {
+		if (const auto forumTopic = row.key.forumTopic()) {
+			controller->showRepliesForMessage(
+				forumTopic->forum(),
+				forumTopic->rootId());
+		} else if (history && history->peer->isForum()) {
 			controller->openForum(history->peer->asChannel());
 		} else if (history) {
 			const auto peer = history->peer;
@@ -372,6 +378,8 @@ Widget::Widget(
 					&& _searchFull
 					&& !_searchFullMigrated))) {
 			searchMore();
+		} else if (_openedForum) {
+			_openedForum->forum()->requestTopics();
 		} else {
 			const auto folder = _inner->shownFolder();
 			if (!folder || !folder->chatsList()->loaded()) {
diff --git a/Telegram/SourceFiles/history/history.cpp b/Telegram/SourceFiles/history/history.cpp
index af5d9f0ad4..a9fda3af7b 100644
--- a/Telegram/SourceFiles/history/history.cpp
+++ b/Telegram/SourceFiles/history/history.cpp
@@ -27,6 +27,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_sponsored_messages.h"
 #include "data/data_send_action.h"
 #include "data/data_folder.h"
+#include "data/data_forum.h"
 #include "data/data_photo.h"
 #include "data/data_channel.h"
 #include "data/data_chat.h"
@@ -1123,6 +1124,11 @@ void History::newItemAdded(not_null<HistoryItem*> item) {
 	if (!folderKnown()) {
 		owner().histories().requestDialogEntry(this);
 	}
+	if (item->isTopicStart() && peer->isForum()) {
+		if (const auto forum = peer->asChannel()->forum()) {
+			forum->topicAdded(item);
+		}
+	}
 }
 
 void History::registerClientSideMessage(not_null<HistoryItem*> item) {
@@ -2019,12 +2025,13 @@ Dialogs::UnreadState History::chatListUnreadState() const {
 	auto result = Dialogs::UnreadState();
 	const auto count = _unreadCount.value_or(0);
 	const auto mark = !count && _unreadMark;
+	const auto muted = mute();
 	result.messages = count;
-	result.messagesMuted = mute() ? count : 0;
+	result.messagesMuted = muted ? count : 0;
 	result.chats = count ? 1 : 0;
-	result.chatsMuted = (count && mute()) ? 1 : 0;
+	result.chatsMuted = (count && muted) ? 1 : 0;
 	result.marks = mark ? 1 : 0;
-	result.marksMuted = (mark && mute()) ? 1 : 0;
+	result.marksMuted = (mark && muted) ? 1 : 0;
 	result.known = _unreadCount.has_value();
 	return result;
 }
diff --git a/Telegram/SourceFiles/history/history_item.cpp b/Telegram/SourceFiles/history/history_item.cpp
index ce3f4fe923..d593d7dbe9 100644
--- a/Telegram/SourceFiles/history/history_item.cpp
+++ b/Telegram/SourceFiles/history/history_item.cpp
@@ -1424,7 +1424,8 @@ MessageFlags FlagsFromMTP(
 		| ((flags & MTP::f_reply_markup) ? Flag::HasReplyMarkup : Flag())
 		| ((flags & MTP::f_from_scheduled) ? Flag::IsOrWasScheduled : Flag())
 		| ((flags & MTP::f_views) ? Flag::HasViews : Flag())
-		| ((flags & MTP::f_noforwards) ? Flag::NoForwards : Flag());
+		| ((flags & MTP::f_noforwards) ? Flag::NoForwards : Flag())
+		| ((flags & MTP::f_topic_start) ? Flag::TopicStart : Flag());
 }
 
 MessageFlags FlagsFromMTP(
diff --git a/Telegram/SourceFiles/history/history_item.h b/Telegram/SourceFiles/history/history_item.h
index c402150b42..b6e66fece1 100644
--- a/Telegram/SourceFiles/history/history_item.h
+++ b/Telegram/SourceFiles/history/history_item.h
@@ -145,6 +145,9 @@ public:
 	[[nodiscard]] bool isPinned() const {
 		return _flags & MessageFlag::Pinned;
 	}
+	[[nodiscard]] bool isTopicStart() const {
+		return _flags & MessageFlag::TopicStart;
+	}
 	[[nodiscard]] bool unread() const;
 	[[nodiscard]] bool showNotification() const;
 	void markClientSideAsRead();