Preload chats in support switch.

Telegram/SourceFiles/dialogs/dialogs_inner_widget.cpp

@@ -3025,6 +3025,24 @@ void InnerWidget::updateRowCornerStatusShown(
 	}
 }
 
+RowDescriptor InnerWidget::resolveChatNext(RowDescriptor from) const {
+	const auto row = from.key ? from : _controller->activeChatEntryCurrent();
+	return row.key
+		? computeJump(
+			chatListEntryAfter(row),
+			JumpSkip::NextOrEnd)
+		: row;
+}
+
+RowDescriptor InnerWidget::resolveChatPrevious(RowDescriptor from) const {
+	const auto row = from.key ? from : _controller->activeChatEntryCurrent();
+	return row.key
+		? computeJump(
+			chatListEntryBefore(row),
+			JumpSkip::PreviousOrBegin)
+		: row;
+}
+
 void InnerWidget::setupShortcuts() {
 	Shortcuts::Requests(
 	) | rpl::filter([=] {
@@ -3197,7 +3215,7 @@ void InnerWidget::setupShortcuts() {
 
 RowDescriptor InnerWidget::computeJump(
 		const RowDescriptor &to,
-		JumpSkip skip) {
+		JumpSkip skip) const {
 	auto result = to;
 	if (result.key) {
 		const auto down = (skip == JumpSkip::NextOrEnd)

Telegram/SourceFiles/dialogs/dialogs_inner_widget.h

@@ -125,6 +125,9 @@ public:
 	[[nodiscard]] rpl::producer<ChosenRow> chosenRow() const;
 	[[nodiscard]] rpl::producer<> updated() const;
 
+	[[nodiscard]] RowDescriptor resolveChatNext(RowDescriptor from = {}) const;
+	[[nodiscard]] RowDescriptor resolveChatPrevious(RowDescriptor from = {}) const;
+
 	~InnerWidget();
 
 public Q_SLOTS:
@@ -238,7 +241,7 @@ private:
 	void setupShortcuts();
 	RowDescriptor computeJump(
 		const RowDescriptor &to,
-		JumpSkip skip);
+		JumpSkip skip) const;
 	bool jumpToDialogRow(RowDescriptor to);
 
 	RowDescriptor chatListEntryBefore(const RowDescriptor &which) const;

Telegram/SourceFiles/dialogs/dialogs_widget.cpp

@@ -1685,6 +1685,14 @@ void Widget::updateForwardBar() {
 	update();
 }
 
+RowDescriptor Widget::resolveChatNext(RowDescriptor from) const {
+	return _inner->resolveChatNext(from);
+}
+
+RowDescriptor Widget::resolveChatPrevious(RowDescriptor from) const {
+   return _inner->resolveChatPrevious(from);
+}
+
 void Widget::keyPressEvent(QKeyEvent *e) {
 	if (e->key() == Qt::Key_Escape) {
 		if (_openedFolder) {

Telegram/SourceFiles/dialogs/dialogs_widget.h

@@ -91,6 +91,9 @@ public:
 
 	[[nodiscard]] rpl::producer<> closeForwardBarRequests() const;
 
+	[[nodiscard]] RowDescriptor resolveChatNext(RowDescriptor from = {}) const;
+	[[nodiscard]] RowDescriptor resolveChatPrevious(RowDescriptor from = {}) const;
+
 	// Float player interface.
 	bool floatPlayerHandleWheelEvent(QEvent *e) override;
 	QRect floatPlayerAvailableRect() override;

Telegram/SourceFiles/history/history_widget.cpp

@@ -818,6 +818,13 @@ HistoryWidget::HistoryWidget(
 		}
 	}, lifetime());
 
+	if (session().supportMode()) {
+		session().data().chatListEntryRefreshes(
+		) | rpl::start_with_next([=] {
+			crl::on_main(this, [=] { checkSupportPreload(true); });
+		}, lifetime());
+	}
+
 	setupScheduledToggle();
 	setupSendAsToggle();
 	orderWidgets();
@@ -2299,9 +2306,11 @@ void HistoryWidget::setHistory(History *history) {
 			history->forceFullResize();
 		}
 	};
+
 	if (_history) {
 		unregisterDraftSources();
 		clearAllLoadRequests();
+		clearSupportPreloadRequest();
 		const auto wasHistory = base::take(_history);
 		const auto wasMigrated = base::take(_migrated);
 		unloadHeavyViewParts(wasHistory);
@@ -2371,6 +2380,16 @@ void HistoryWidget::clearDelayedShowAtRequest() {
 	}
 }
 
+void HistoryWidget::clearSupportPreloadRequest() {
+	Expects(_history != nullptr);
+
+	if (_supportPreloadRequest) {
+		auto &histories = _history->owner().histories();
+		histories.cancelRequest(_supportPreloadRequest);
+		_supportPreloadRequest = 0;
+	}
+}
+
 void HistoryWidget::clearAllLoadRequests() {
 	Expects(_history != nullptr);
 
@@ -2990,6 +3009,9 @@ void HistoryWidget::messagesReceived(PeerData *peer, const MTPmessages_Messages
 		setMsgId(_delayedShowAtMsgId);
 		historyLoaded();
 	}
+	if (session().supportMode()) {
+		crl::on_main(this, [=] { checkSupportPreload(); });
+	}
 }
 
 void HistoryWidget::historyLoaded() {
@@ -3337,6 +3359,96 @@ void HistoryWidget::preloadHistoryByScroll() {
 	if (scrollTop <= kPreloadHeightsCount * scrollHeight) {
 		loadMessages();
 	}
+	if (session().supportMode()) {
+		crl::on_main(this, [=] { checkSupportPreload(); });
+	}
+}
+
+void HistoryWidget::checkSupportPreload(bool force) {
+	if (!_history
+		|| _firstLoadRequest
+		|| _preloadRequest
+		|| _preloadDownRequest
+		|| (_supportPreloadRequest && !force)
+		|| controller()->activeChatEntryCurrent().key.history() != _history) {
+		return;
+	}
+
+	const auto setting = session().settings().supportSwitch();
+	const auto command = Support::GetSwitchCommand(setting);
+	const auto descriptor = !command
+		? Dialogs::RowDescriptor()
+		: (*command == Shortcuts::Command::ChatNext)
+		? controller()->resolveChatNext()
+		: controller()->resolveChatPrevious();
+	auto history = descriptor.key.history();
+	if (!history || _supportPreloadHistory == history) {
+		return;
+	}
+	clearSupportPreloadRequest();
+	_supportPreloadHistory = history;
+	auto offsetId = MsgId();
+	auto offset = 0;
+	auto loadCount = kMessagesPerPage;
+	if (const auto around = history->loadAroundId()) {
+		history->getReadyFor(ShowAtUnreadMsgId);
+		offset = -loadCount / 2;
+		offsetId = around;
+	}
+	const auto offsetDate = 0;
+	const auto maxId = 0;
+	const auto minId = 0;
+	const auto historyHash = uint64(0);
+	const auto tmp = history->peer->name.toStdString();
+	const auto tmp2 = _history->peer->name.toStdString();
+	LOG(("PRELOADING FROM: %1 FOR: %2").arg(_history->peer->name).arg(history->peer->name));
+	const auto type = Data::Histories::RequestType::History;
+	auto &histories = history->owner().histories();
+	_supportPreloadRequest = histories.sendRequest(history, type, [=](Fn<void()> finish) {
+		return history->session().api().request(MTPmessages_GetHistory(
+			history->peer->input,
+			MTP_int(offsetId),
+			MTP_int(offsetDate),
+			MTP_int(offset),
+			MTP_int(loadCount),
+			MTP_int(maxId),
+			MTP_int(minId),
+			MTP_long(historyHash)
+		)).done([=](const MTPmessages_Messages &result) {
+			if (const auto around = history->loadAroundId()) {
+				if (around != offsetId) {
+					LOG(("RE-PRELOADING FOR: %1").arg(history->peer->name));
+					_supportPreloadRequest = 0;
+					_supportPreloadHistory = nullptr;
+					crl::on_main(this, [=] { checkSupportPreload(); });
+					return;
+				}
+				history->clear(History::ClearType::Unload);
+				history->getReadyFor(ShowAtUnreadMsgId);
+			} else if (offsetId) {
+				LOG(("RE-PRELOADING FOR: %1").arg(history->peer->name));
+				_supportPreloadRequest = 0;
+				_supportPreloadHistory = nullptr;
+				crl::on_main(this, [=] { checkSupportPreload(); });
+				return;
+			} else {
+				history->clear(History::ClearType::Unload);
+				history->getReadyFor(ShowAtTheEndMsgId);
+			}
+			LOG(("PRELOADED FOR: %1").arg(history->peer->name));
+			auto count = 0;
+			const QVector<MTPMessage> emptyList, *histList = &emptyList;
+			result.match([](const MTPDmessages_messagesNotModified&) {
+			}, [&](const auto &data) {
+				history->owner().processUsers(data.vusers());
+				history->owner().processChats(data.vchats());
+				history->addOlderSlice(data.vmessages().v);
+			});
+			finish();
+		}).fail([=](const MTP::Error &error) {
+			finish();
+		}).send();
+	});
 }
 
 void HistoryWidget::checkReplyReturns() {
@@ -7534,10 +7646,7 @@ HistoryWidget::~HistoryWidget() {
 		// Saving a draft on account switching.
 		saveFieldToHistoryLocalDraft();
 		session().api().saveDraftToCloudDelayed(_history);
-
-		clearAllLoadRequests();
 		setHistory(nullptr);
-		unregisterDraftSources();
 	}
 	setTabbedPanel(nullptr);
 }

Telegram/SourceFiles/history/history_widget.h

@@ -234,6 +234,7 @@ public:
 		Ui::ReportReason reason,
 		Fn<void(MessageIdsList)> callback);
 	void clearAllLoadRequests();
+	void clearSupportPreloadRequest();
 	void clearDelayedShowAtRequest();
 	void clearDelayedShowAt();
 	void saveFieldToHistoryLocalDraft();
@@ -598,6 +599,7 @@ private:
 	bool readyToForward() const;
 	bool hasSilentToggle() const;
 
+	void checkSupportPreload(bool force = false);
 	void handleSupportSwitch(not_null<History*> updated);
 
 	void inlineBotResolveDone(const MTPcontacts_ResolvedPeer &result);
@@ -685,6 +687,9 @@ private:
 	MsgId _delayedShowAtMsgId = -1;
 	int _delayedShowAtRequest = 0; // Not real mtpRequestId.
 
+	History *_supportPreloadHistory = nullptr;
+	int _supportPreloadRequest = 0; // Not real mtpRequestId.
+
 	object_ptr<HistoryView::TopBarWidget> _topBar;
 	object_ptr<Ui::ContinuousScroll> _scroll;
 	QPointer<HistoryInner> _list;

Telegram/SourceFiles/mainwidget.cpp

@@ -1779,6 +1779,16 @@ bool MainWidget::isThirdSectionShown() const {
 	return _thirdSection != nullptr;
 }
 
+Dialogs::RowDescriptor MainWidget::resolveChatNext(
+		Dialogs::RowDescriptor from) const {
+	return _dialogs ? _dialogs->resolveChatNext(from) : Dialogs::RowDescriptor();
+}
+
+Dialogs::RowDescriptor MainWidget::resolveChatPrevious(
+		Dialogs::RowDescriptor from) const {
+	return _dialogs ? _dialogs->resolveChatPrevious(from) : Dialogs::RowDescriptor();
+}
+
 bool MainWidget::stackIsEmpty() const {
 	return _stack.empty();
 }

Telegram/SourceFiles/mainwidget.h

@@ -128,6 +128,11 @@ public:
 	[[nodiscard]] bool isMainSectionShown() const;
 	[[nodiscard]] bool isThirdSectionShown() const;
 
+	[[nodiscard]] Dialogs::RowDescriptor resolveChatNext(
+		Dialogs::RowDescriptor from) const;
+	[[nodiscard]] Dialogs::RowDescriptor resolveChatPrevious(
+		Dialogs::RowDescriptor from) const;
+
 	void returnTabbedSelector();
 
 	void showAnimated(const QPixmap &bgAnimCache, bool back = false);

Telegram/SourceFiles/support/support_common.cpp

@@ -21,14 +21,19 @@ Qt::KeyboardModifiers SkipSwitchModifiers() {
 	return Qt::ControlModifier | Qt::ShiftModifier;
 }
 
-FnMut<bool()> GetSwitchMethod(SwitchSettings value) {
+std::optional<Shortcuts::Command> GetSwitchCommand(SwitchSettings value) {
 	switch (value) {
 	case SwitchSettings::Next:
-		return Shortcuts::RequestHandler(Shortcuts::Command::ChatNext);
+		return Shortcuts::Command::ChatNext;
 	case SwitchSettings::Previous:
-		return Shortcuts::RequestHandler(Shortcuts::Command::ChatPrevious);
+		return Shortcuts::Command::ChatPrevious;
 	}
-	return nullptr;
+	return std::nullopt;
+}
+
+FnMut<bool()> GetSwitchMethod(SwitchSettings value) {
+	const auto command = GetSwitchCommand(value);
+	return command ? Shortcuts::RequestHandler(*command) : nullptr;
 }
 
 } // namespace Support

Telegram/SourceFiles/support/support_common.h

@@ -7,6 +7,10 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #pragma once
 
+namespace Shortcuts {
+enum class Command;
+} // namespace Shortcuts
+
 namespace Support {
 
 enum class SwitchSettings {
@@ -15,8 +19,10 @@ enum class SwitchSettings {
 	Previous,
 };
 
-Qt::KeyboardModifiers SkipSwitchModifiers();
+[[nodiscard]] Qt::KeyboardModifiers SkipSwitchModifiers();
-bool HandleSwitch(Qt::KeyboardModifiers modifiers);
+[[nodiscard]] bool HandleSwitch(Qt::KeyboardModifiers modifiers);
-FnMut<bool()> GetSwitchMethod(SwitchSettings value);
+[[nodiscard]] std::optional<Shortcuts::Command> GetSwitchCommand(
+	SwitchSettings value);
+[[nodiscard]] FnMut<bool()> GetSwitchMethod(SwitchSettings value);
 
 } // namespace Support

Telegram/SourceFiles/window/window_session_controller.cpp

@@ -795,6 +795,16 @@ bool SessionController::jumpToChatListEntry(Dialogs::RowDescriptor row) {
 	return false;
 }
 
+Dialogs::RowDescriptor SessionController::resolveChatNext(
+		Dialogs::RowDescriptor from) const {
+	return content()->resolveChatNext(from);
+}
+
+Dialogs::RowDescriptor SessionController::resolveChatPrevious(
+		Dialogs::RowDescriptor from) const {
+	return content()->resolveChatPrevious(from);
+}
+
 void SessionController::pushToChatEntryHistory(Dialogs::RowDescriptor row) {
 	if (!_chatEntryHistory.empty()
 		&& _chatEntryHistory[_chatEntryHistoryPosition] == row) {

Telegram/SourceFiles/window/window_session_controller.h

@@ -301,6 +301,12 @@ public:
 	rpl::producer<Dialogs::RowDescriptor> activeChatEntryValue() const;
 	rpl::producer<Dialogs::Key> activeChatValue() const;
 	bool jumpToChatListEntry(Dialogs::RowDescriptor row);
+
+	[[nodiscard]] Dialogs::RowDescriptor resolveChatNext(
+		Dialogs::RowDescriptor from = {}) const;
+	[[nodiscard]] Dialogs::RowDescriptor resolveChatPrevious(
+		Dialogs::RowDescriptor from = {}) const;
+
 	void showEditPeerBox(PeerData *peer);
 
 	void enableGifPauseReason(GifPauseReason reason);