Support topic on-the-fly creation.

Telegram/SourceFiles/data/data_forum.cpp

@@ -124,20 +124,18 @@ void Forum::applyTopicAdded(
 		MsgId rootId,
 		const QString &title,
 		DocumentId iconId) {
-	if (const auto i = _topics.find(rootId); i != end(_topics)) {
-		i->second->applyTitle(title);
-		i->second->applyIconId(iconId);
-	} else {
-		const auto raw = _topics.emplace(
+	const auto i = _topics.find(rootId);
+	const auto raw = (i != end(_topics))
+		? i->second.get()
+		: _topics.emplace(
 			rootId,
 			std::make_unique<ForumTopic>(_history, rootId)
 		).first->second.get();
-		raw->applyTitle(title);
-		raw->applyIconId(iconId);
-		if (!creating(rootId)) {
-			raw->addToChatList(FilterId(), topicsList());
-			_chatsListChanges.fire({});
-		}
+	raw->applyTitle(title);
+	raw->applyIconId(iconId);
+	if (!creating(rootId)) {
+		raw->addToChatList(FilterId(), topicsList());
+		_chatsListChanges.fire({});
 	}
 }
 
@@ -171,6 +169,25 @@ bool Forum::creating(MsgId rootId) const {
 	return _creatingRootIds.contains(rootId);
 }
 
+void Forum::created(MsgId rootId, MsgId realId) {
+	if (rootId == realId) {
+		return;
+	}
+	_creatingRootIds.remove(rootId);
+	const auto i = _topics.find(rootId);
+	Assert(i != end(_topics));
+	auto topic = std::move(i->second);
+	_topics.erase(i);
+	const auto id = FullMsgId(_history->peer->id, realId);
+	if (!_topics.contains(realId)) {
+		_topics.emplace(
+			realId,
+			std::move(topic)
+		).first->second->setRealRootId(realId);
+	}
+	_history->owner().notifyItemIdChange({ id, rootId });
+}
+
 ForumTopic *Forum::topicFor(not_null<HistoryItem*> item) {
 	const auto maybe = topicFor(item->replyToTop());
 	return maybe ? maybe : topicFor(item->topicRootId());

Telegram/SourceFiles/data/data_forum.h

@@ -36,6 +36,7 @@ public:
 		const QString &title,
 		DocumentId iconId);
 	void applyTopicRemoved(MsgId rootId);
+	void applyTopicCreated(MsgId rootId, MsgId realId);
 	[[nodiscard]] ForumTopic *topicFor(not_null<HistoryItem*> item);
 	[[nodiscard]] ForumTopic *topicFor(MsgId rootId);
 
@@ -46,6 +47,7 @@ public:
 		DocumentId iconId);
 	void discardCreatingId(MsgId rootId);
 	[[nodiscard]] bool creating(MsgId rootId) const;
+	void created(MsgId rootId, MsgId realId);
 
 private:
 	void applyReceivedTopics(

Telegram/SourceFiles/data/data_forum_topic.cpp

@@ -29,6 +29,8 @@ ForumTopic::ForumTopic(not_null<History*> history, MsgId rootId)
 , _rootId(rootId) {
 }
 
+ForumTopic::~ForumTopic() = default;
+
 not_null<ChannelData*> ForumTopic::channel() const {
 	return _history->peer->asChannel();
 }
@@ -45,6 +47,10 @@ MsgId ForumTopic::rootId() const {
 	return _rootId;
 }
 
+void ForumTopic::setRealRootId(MsgId realId) {
+	_rootId = realId;
+}
+
 void ForumTopic::applyTopic(const MTPForumTopic &topic) {
 	Expects(_rootId == topic.data().vid().v);
 

Telegram/SourceFiles/data/data_forum_topic.h

@@ -30,6 +30,7 @@ public:
 	static constexpr auto kGeneralId = 1;
 
 	ForumTopic(not_null<History*> history, MsgId rootId);
+	~ForumTopic();
 
 	ForumTopic(const ForumTopic &) = delete;
 	ForumTopic &operator=(const ForumTopic &) = delete;
@@ -42,6 +43,8 @@ public:
 		return (_rootId == kGeneralId);
 	}
 
+	void setRealRootId(MsgId realId);
+
 	void applyTopic(const MTPForumTopic &topic);
 
 	TimeId adjustedChatListTimeId() const override;
@@ -109,7 +112,7 @@ private:
 
 	const not_null<History*> _history;
 	const not_null<Dialogs::MainList*> _list;
-	const MsgId _rootId = 0;
+	MsgId _rootId = 0;
 
 	QString _title;
 	DocumentId _iconId = 0;

Telegram/SourceFiles/data/data_histories.cpp

@@ -11,8 +11,11 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_channel.h"
 #include "data/data_chat.h"
 #include "data/data_folder.h"
+#include "data/data_forum.h"
+#include "data/data_forum_topic.h"
 #include "data/data_scheduled_messages.h"
 #include "base/unixtime.h"
+#include "base/random.h"
 #include "main/main_session.h"
 #include "window/notifications_manager.h"
 #include "history/history.h"
@@ -841,14 +844,74 @@ int Histories::sendRequest(
 	return id;
 }
 
+void Histories::sendCreateTopicRequest(
+		not_null<History*> history,
+		MsgId rootId) {
+	Expects(history->peer->isChannel());
+
+	const auto forum = history->peer->forum();
+	Assert(forum != nullptr);
+	const auto topic = forum->topicFor(rootId);
+	Assert(topic != nullptr);
+	const auto randomId = base::RandomValue<uint64>();
+	session().data().registerMessageRandomId(
+		randomId,
+		{ history->peer->id, rootId });
+	const auto api = &session().api();
+	using Flag = MTPchannels_CreateForumTopic::Flag;
+	api->request(MTPchannels_CreateForumTopic(
+		MTP_flags(topic->iconId() ? Flag::f_icon_emoji_id : Flag(0)),
+		history->peer->asChannel()->inputChannel,
+		MTP_string(topic->title()),
+		MTP_long(topic->iconId()),
+		MTP_long(randomId),
+		MTPInputPeer() // send_as
+	)).done([=](const MTPUpdates &result) {
+		//AssertIsDebug();
+		//const auto id = result.c_updates().vupdates().v.front().c_updateMessageID().vrandom_id().v;
+		//session().data().registerMessageRandomId(
+		//	id,
+		//	{ history->peer->id, rootId });
+		api->applyUpdates(result, randomId);
+	}).fail([=](const MTP::Error &error) {
+		api->sendMessageFail(error, history->peer, randomId);
+	}).send();
+}
+
+bool Histories::isCreatingTopic(
+		not_null<History*> history,
+		MsgId rootId) const {
+	const auto forum = history->peer->forum();
+	return forum && forum->creating(rootId);
+}
+
 int Histories::sendPreparedMessage(
 		not_null<History*> history,
 		MsgId replyTo,
 		uint64 randomId,
-		PreparedMessage message,
+		Fn<PreparedMessage(MsgId replyTo)> message,
 		Fn<void(const MTPUpdates&, const MTP::Response&)> done,
 		Fn<void(const MTP::Error&, const MTP::Response&)> fail) {
-	return v::match(message, [&](const auto &request) {
+	if (isCreatingTopic(history, replyTo)) {
+		const auto id = ++_requestAutoincrement;
+		const auto creatingId = FullMsgId(history->peer->id, replyTo);
+		auto i = _creatingTopics.find(creatingId);
+		if (i == end(_creatingTopics)) {
+			sendCreateTopicRequest(history, replyTo);
+			i = _creatingTopics.emplace(creatingId).first;
+		}
+		i->second.push_back({
+			.randomId = randomId,
+			.message = std::move(message),
+			.done = std::move(done),
+			.fail = std::move(fail),
+			.requestId = id,
+		});
+		_creatingTopicRequests.emplace(id);
+		return id;
+	}
+	const auto realTo = convertTopicReplyTo(history, replyTo);
+	return v::match(message(realTo), [&](const auto &request) {
 		const auto type = RequestType::Send;
 		return sendRequest(history, type, [=](Fn<void()> finish) {
 			const auto session = &_owner->session();
@@ -874,6 +937,54 @@ int Histories::sendPreparedMessage(
 	});
 }
 
+void Histories::checkTopicCreated(FullMsgId rootId, MsgId realId) {
+	const auto i = _creatingTopics.find(rootId);
+	if (i != end(_creatingTopics)) {
+		auto scheduled = base::take(i->second);
+		_creatingTopics.erase(i);
+
+		_createdTopicIds.emplace(rootId, realId);
+
+		if (const auto forum = _owner->peer(rootId.peer)->forum()) {
+			forum->created(rootId.msg, realId);
+		}
+
+		const auto history = _owner->history(rootId.peer);
+		for (auto &entry : scheduled) {
+			_creatingTopicRequests.erase(entry.requestId);
+			//AssertIsDebug();
+			sendPreparedMessage(
+				history,
+				realId,
+				entry.randomId,
+				std::move(entry.message),
+				std::move(entry.done),
+				std::move(entry.fail));
+		}
+		for (const auto &item : history->clientSideMessages()) {
+			const auto replace = [&](MsgId nowId) {
+				return (nowId == rootId.msg) ? realId : nowId;
+			};
+			if (item->replyToTop() == rootId.msg) {
+				item->setReplyFields(
+					replace(item->replyToId()),
+					realId,
+					true);
+			}
+		}
+	}
+}
+
+MsgId Histories::convertTopicReplyTo(
+		not_null<History*> history,
+		MsgId replyTo) const {
+	if (!replyTo) {
+		return {};
+	}
+	const auto i = _createdTopicIds.find({ history->peer->id, replyTo });
+	return (i != end(_createdTopicIds)) ? i->second : replyTo;
+}
+
 void Histories::checkPostponed(not_null<History*> history, int id) {
 	if (const auto state = lookup(history)) {
 		finishSentRequest(history, state, id);
@@ -883,6 +994,9 @@ void Histories::checkPostponed(not_null<History*> history, int id) {
 void Histories::cancelRequest(int id) {
 	if (!id) {
 		return;
+	} else if (_creatingTopicRequests.contains(id)) {
+		cancelDelayedByTopicRequest(id);
+		return;
 	}
 	const auto history = _historyByRequest.take(id);
 	if (!history) {
@@ -896,6 +1010,15 @@ void Histories::cancelRequest(int id) {
 	finishSentRequest(*history, state, id);
 }
 
+void Histories::cancelDelayedByTopicRequest(int id) {
+	for (auto &[rootId, messages] : _creatingTopics) {
+		messages.erase(
+			ranges::remove(messages, id, &DelayedByTopicMessage::requestId),
+			end(messages));
+	}
+	_creatingTopicRequests.remove(id);
+}
+
 void Histories::finishSentRequest(
 		not_null<History*> history,
 		not_null<State*> state,

Telegram/SourceFiles/data/data_histories.h

@@ -104,10 +104,25 @@ public:
 		not_null<History*> history,
 		MsgId replyTo,
 		uint64 randomId,
-		PreparedMessage message,
-		Fn<void(const MTPUpdates&, const MTP::Response &)> done,
+		Fn<PreparedMessage(MsgId replyTo)> message,
+		Fn<void(const MTPUpdates&, const MTP::Response&)> done,
 		Fn<void(const MTP::Error&, const MTP::Response&)> fail);
 
+	struct ReplyToPlaceholder {
+	};
+	template <typename RequestType, typename ...Args>
+	static Fn<Histories::PreparedMessage(MsgId)> PrepareMessage(
+			const Args &...args) {
+		return [=](MsgId replyTo) {
+			return RequestType(ReplaceReplyTo(args, replyTo)...);
+		};
+	}
+
+	void checkTopicCreated(FullMsgId rootId, MsgId realId);
+	[[nodiscard]] MsgId convertTopicReplyTo(
+		not_null<History*> history,
+		MsgId replyTo) const;
+
 private:
 	struct PostponedHistoryRequest {
 		Fn<mtpRequestId(Fn<void()> finish)> generator;
@@ -130,6 +145,22 @@ private:
 		MsgId aroundId = 0;
 		mtpRequestId requestId = 0;
 	};
+	struct DelayedByTopicMessage {
+		uint64 randomId = 0;
+		Fn<PreparedMessage(MsgId replyTo)> message;
+		Fn<void(const MTPUpdates&, const MTP::Response&)> done;
+		Fn<void(const MTP::Error&, const MTP::Response&)> fail;
+		int requestId = 0;
+	};
+
+	template <typename Arg>
+	static auto ReplaceReplyTo(Arg arg, MsgId replyTo) {
+		return arg;
+	}
+	template <>
+	static auto ReplaceReplyTo(ReplyToPlaceholder, MsgId replyTo) {
+		return MTP_int(replyTo);
+	}
 
 	void readInboxTill(not_null<History*> history, MsgId tillId, bool force);
 	void sendReadRequests();
@@ -147,6 +178,12 @@ private:
 
 	void sendDialogRequests();
 
+	[[nodiscard]] bool isCreatingTopic(
+		not_null<History*> history,
+		MsgId rootId) const;
+	void sendCreateTopicRequest(not_null<History*> history, MsgId rootId);
+	void cancelDelayedByTopicRequest(int id);
+
 	const not_null<Session*> _owner;
 
 	std::unordered_map<PeerId, std::unique_ptr<History>> _map;
@@ -169,6 +206,12 @@ private:
 		not_null<History*>,
 		ChatListGroupRequest> _chatListGroupRequests;
 
+	base::flat_map<
+		FullMsgId,
+		std::vector<DelayedByTopicMessage>> _creatingTopics;
+	base::flat_map<FullMsgId, MsgId> _createdTopicIds;
+	base::flat_set<mtpRequestId> _creatingTopicRequests;
+
 };
 
 } // namespace Data

Telegram/SourceFiles/data/data_replies_list.cpp

@@ -137,9 +137,6 @@ void RepliesList::appendClientSideMessages(MessagesSlice &slice) {
 		}
 		slice.ids.reserve(messages.size());
 		for (const auto &item : messages) {
-			const auto checkId = (_rootId == ForumTopic::kGeneralId)
-				? item->topicRootId()
-				: item->replyToTop();
 			if (!item->inThread(_rootId)) {
 				continue;
 			}

Telegram/SourceFiles/data/data_session.cpp

@@ -1407,10 +1407,12 @@ rpl::producer<not_null<HistoryItem*>> Session::newItemAdded() const {
 	return _newItemAdded.events();
 }
 
-void Session::changeMessageId(PeerId peerId, MsgId wasId, MsgId nowId) {
+HistoryItem *Session::changeMessageId(PeerId peerId, MsgId wasId, MsgId nowId) {
 	const auto list = messagesListForInsert(peerId);
-	auto i = list->find(wasId);
-	Assert(i != list->end());
+	const auto i = list->find(wasId);
+	if (i == list->end()) {
+		return nullptr;
+	}
 	const auto item = i->second;
 	list->erase(i);
 	const auto [j, ok] = list->emplace(nowId, item);
@@ -1427,6 +1429,7 @@ void Session::changeMessageId(PeerId peerId, MsgId wasId, MsgId nowId) {
 	}
 
 	Ensures(ok);
+	return item;
 }
 
 bool Session::queryItemVisibility(not_null<HistoryItem*> item) const {
@@ -1448,19 +1451,23 @@ void Session::itemVisibilitiesUpdated() {
 }
 
 void Session::notifyItemIdChange(IdChange event) {
-	const auto item = event.item;
-	changeMessageId(item->history()->peer->id, event.oldId, item->id);
+	const auto item = changeMessageId(
+		event.newId.peer,
+		event.oldId,
+		event.newId.msg);
 
 	_itemIdChanges.fire_copy(event);
 
-	const auto refreshViewDataId = [](not_null<ViewElement*> view) {
-		view->refreshDataId();
-	};
-	enumerateItemViews(item, refreshViewDataId);
-	if (const auto group = groups().find(item)) {
-		const auto leader = group->items.front();
-		if (leader != item) {
-			enumerateItemViews(leader, refreshViewDataId);
+	if (item) {
+		const auto refreshViewDataId = [](not_null<ViewElement*> view) {
+			view->refreshDataId();
+		};
+		enumerateItemViews(item, refreshViewDataId);
+		if (const auto group = groups().find(item)) {
+			const auto leader = group->items.front();
+			if (leader != item) {
+				enumerateItemViews(leader, refreshViewDataId);
+			}
 		}
 	}
 }

Telegram/SourceFiles/data/data_session.h

@@ -243,7 +243,7 @@ public:
 	void itemVisibilitiesUpdated();
 
 	struct IdChange {
-		not_null<HistoryItem*> item;
+		FullMsgId newId;
 		MsgId oldId = 0;
 	};
 	void notifyItemIdChange(IdChange event);
@@ -728,7 +728,7 @@ private:
 	not_null<Messages*> messagesListForInsert(PeerId peerId);
 	not_null<HistoryItem*> registerMessage(
 		std::unique_ptr<HistoryItem> item);
-	void changeMessageId(PeerId peerId, MsgId wasId, MsgId nowId);
+	HistoryItem *changeMessageId(PeerId peerId, MsgId wasId, MsgId nowId);
 	void removeDependencyMessage(not_null<HistoryItem*> item);
 
 	void photoApplyFields(