From 28032e5e0d9f84ab665d7ce1fa9f4eebc48d1077 Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Fri, 21 Feb 2020 18:02:13 +0400
Subject: [PATCH] Fix jump to a specific message.

---
 Telegram/SourceFiles/data/data_histories.cpp  |  7 ++-
 .../SourceFiles/history/history_widget.cpp    | 49 +++++++++++++------
 Telegram/SourceFiles/history/history_widget.h |  3 +-
 3 files changed, 38 insertions(+), 21 deletions(-)

diff --git a/Telegram/SourceFiles/data/data_histories.cpp b/Telegram/SourceFiles/data/data_histories.cpp
index 25a9dfe35..449f900ee 100644
--- a/Telegram/SourceFiles/data/data_histories.cpp
+++ b/Telegram/SourceFiles/data/data_histories.cpp
@@ -597,10 +597,9 @@ int Histories::sendRequest(
 }
 
 void Histories::checkPostponed(not_null<History*> history, int id) {
-	const auto state = lookup(history);
-	Assert(state != nullptr);
-
-	finishSentRequest(history, state, id);
+	if (const auto state = lookup(history)) {
+		finishSentRequest(history, state, id);
+	}
 }
 
 void Histories::cancelRequest(int id) {
diff --git a/Telegram/SourceFiles/history/history_widget.cpp b/Telegram/SourceFiles/history/history_widget.cpp
index 043476576..715f9fdf9 100644
--- a/Telegram/SourceFiles/history/history_widget.cpp
+++ b/Telegram/SourceFiles/history/history_widget.cpp
@@ -1916,9 +1916,13 @@ void HistoryWidget::showHistory(
 }
 
 void HistoryWidget::clearDelayedShowAt() {
+	_delayedShowAtMsgId = -1;
+	clearDelayedShowAtRequest();
+}
+
+void HistoryWidget::clearDelayedShowAtRequest() {
 	Expects(_history != nullptr);
 
-	_delayedShowAtMsgId = -1;
 	if (_delayedShowAtRequest) {
 		_history->owner().histories().cancelRequest(_delayedShowAtRequest);
 		_delayedShowAtRequest = 0;
@@ -1929,7 +1933,7 @@ void HistoryWidget::clearAllLoadRequests() {
 	Expects(_history != nullptr);
 
 	auto &histories = _history->owner().histories();
-	clearDelayedShowAt();
+	clearDelayedShowAtRequest();
 	if (_firstLoadRequest) {
 		histories.cancelRequest(_firstLoadRequest);
 		_firstLoadRequest = 0;
@@ -2472,19 +2476,19 @@ void HistoryWidget::messagesReceived(PeerData *peer, const MTPmessages_Messages
 			_migrated->clear(History::ClearType::Unload);
 		}
 
-		_delayedShowAtRequest = 0;
+		clearAllLoadRequests();
+		_firstLoadRequest = -1; // hack - don't updateListSize yet
 		_history->getReadyFor(_delayedShowAtMsgId);
 		if (_history->isEmpty()) {
-			clearAllLoadRequests();
-			_firstLoadRequest = -1; // hack - don't updateListSize yet
 			addMessagesToFront(peer, *histList);
-			_firstLoadRequest = 0;
-			if (_history->loadedAtTop()
-				&& _history->isEmpty()
-				&& count > 0) {
-				firstLoadMessages();
-				return;
-			}
+		}
+		_firstLoadRequest = 0;
+
+		if (_history->loadedAtTop()
+			&& _history->isEmpty()
+			&& count > 0) {
+			firstLoadMessages();
+			return;
 		}
 		while (_replyReturn) {
 			if (_replyReturn->history() == _history
@@ -2498,6 +2502,7 @@ void HistoryWidget::messagesReceived(PeerData *peer, const MTPmessages_Messages
 			}
 		}
 
+		_delayedShowAtRequest = 0;
 		setMsgId(_delayedShowAtMsgId);
 		historyLoaded();
 	}
@@ -2521,6 +2526,7 @@ bool HistoryWidget::doWeReadMentions() const {
 		&& _list
 		&& _historyInited
 		&& !_firstLoadRequest
+		&& !_delayedShowAtRequest
 		&& !_a_show.animating()
 		&& App::wnd()->doWeMarkAsRead();
 }
@@ -2707,7 +2713,7 @@ void HistoryWidget::delayedShowAt(MsgId showAtMsgId) {
 		return;
 	}
 
-	clearDelayedShowAt();
+	clearAllLoadRequests();
 	_delayedShowAtMsgId = showAtMsgId;
 
 	auto from = _history;
@@ -2799,7 +2805,11 @@ void HistoryWidget::visibleAreaUpdated() {
 }
 
 void HistoryWidget::preloadHistoryIfNeeded() {
-	if (_firstLoadRequest || _scroll->isHidden() || !_peer) {
+	if (_firstLoadRequest
+		|| _delayedShowAtRequest
+		|| _scroll->isHidden()
+		|| !_peer
+		|| !_historyInited) {
 		return;
 	}
 
@@ -2818,7 +2828,11 @@ void HistoryWidget::preloadHistoryIfNeeded() {
 }
 
 void HistoryWidget::preloadHistoryByScroll() {
-	if (_firstLoadRequest || _scroll->isHidden() || !_peer) {
+	if (_firstLoadRequest
+		|| _delayedShowAtRequest
+		|| _scroll->isHidden()
+		|| !_peer
+		|| !_historyInited) {
 		return;
 	}
 
@@ -2834,7 +2848,10 @@ void HistoryWidget::preloadHistoryByScroll() {
 }
 
 void HistoryWidget::checkReplyReturns() {
-	if (_firstLoadRequest || _scroll->isHidden() || !_peer) {
+	if (_firstLoadRequest
+		|| _scroll->isHidden()
+		|| !_peer
+		|| !_historyInited) {
 		return;
 	}
 	auto scrollTop = _scroll->scrollTop();
diff --git a/Telegram/SourceFiles/history/history_widget.h b/Telegram/SourceFiles/history/history_widget.h
index f672559e1..3b6ccafa2 100644
--- a/Telegram/SourceFiles/history/history_widget.h
+++ b/Telegram/SourceFiles/history/history_widget.h
@@ -213,8 +213,9 @@ public:
 	void applyDraft(
 		FieldHistoryAction fieldHistoryAction = FieldHistoryAction::Clear);
 	void showHistory(const PeerId &peer, MsgId showAtMsgId, bool reload = false);
-	void clearDelayedShowAt();
 	void clearAllLoadRequests();
+	void clearDelayedShowAtRequest();
+	void clearDelayedShowAt();
 	void saveFieldToHistoryLocalDraft();
 
 	void applyCloudDraft(History *history);