Read feed while scrolling.

Telegram/Resources/langs/lang.strings

@@ -1024,6 +1024,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 "lng_user_action_upload_file" = "{user} is sending a file";
 "lng_unread_bar#one" = "{count} unread message";
 "lng_unread_bar#other" = "{count} unread messages";
+"lng_unread_bar_some" = "Unread messages";
 
 "lng_maps_point" = "Location";
 "lng_save_photo" = "Save image";

Telegram/SourceFiles/apiwrap.cpp

@@ -55,6 +55,7 @@ constexpr auto kSharedMediaLimit = 100;
 constexpr auto kFeedMessagesLimit = 50;
 constexpr auto kReadFeaturedSetsTimeout = TimeMs(1000);
 constexpr auto kFileLoaderQueueStopTimeout = TimeMs(5000);
+constexpr auto kFeedReadTimeout = TimeMs(1000);
 
 bool IsSilentPost(not_null<HistoryItem*> item, bool silent) {
 	const auto history = item->history();
@@ -133,7 +134,8 @@ ApiWrap::ApiWrap(not_null<AuthSession*> session)
 , _webPagesTimer([this] { resolveWebPages(); })
 , _draftsSaveTimer([this] { saveDraftsToCloud(); })
 , _featuredSetsReadTimer([this] { readFeaturedSets(); })
-, _fileLoader(std::make_unique<TaskQueue>(kFileLoaderQueueStopTimeout)) {
+, _fileLoader(std::make_unique<TaskQueue>(kFileLoaderQueueStopTimeout))
+, _feedReadTimer([this] { readFeeds(); }) {
 }
 
 void ApiWrap::requestChangelog(
@@ -3076,9 +3078,12 @@ void ApiWrap::feedMessagesDone(
 		if (data.has_read_max_position()) {
 			return Data::FeedPositionFromMTP(data.vread_max_position);
 		} else if (!messageId) {
-			return ids.empty()
+			const auto result = ids.empty()
 				? noSkipRange.till
 				: ids.back();
+			return Data::MessagePosition(
+				result.date,
+				FullMsgId(result.fullId.channel, result.fullId.msg - 1));
 		}
 		return Data::MessagePosition();
 	}();
@@ -3712,6 +3717,56 @@ void ApiWrap::readServerHistoryForce(not_null<History*> history) {
 	}
 }
 
+void ApiWrap::readFeed(
+		not_null<Data::Feed*> feed,
+		Data::MessagePosition position) {
+	const auto already = feed->unreadPosition();
+	if (already && already >= position) {
+		return;
+	}
+	feed->setUnreadPosition(position);
+	if (!_feedReadsDelayed.contains(feed)) {
+		if (_feedReadsDelayed.empty()) {
+			_feedReadTimer.callOnce(kFeedReadTimeout);
+		}
+		_feedReadsDelayed.emplace(feed, getms(true) + kFeedReadTimeout);
+	}
+}
+
+void ApiWrap::readFeeds() {
+	auto delay = kFeedReadTimeout;
+	const auto now = getms(true);
+	for (auto i = begin(_feedReadsDelayed); i != end(_feedReadsDelayed);) {
+		const auto [feed, time] = *i;
+		if (time > now) {
+			accumulate_min(delay, time - now);
+			++i;
+		} else if (_feedReadRequests.contains(feed)) {
+			++i;
+		} else {
+			const auto position = feed->unreadPosition();
+			const auto requestId = request(MTPchannels_ReadFeed(
+				MTP_int(feed->id()),
+				MTP_feedPosition(
+					MTP_int(position.date),
+					MTP_peerChannel(MTP_int(position.fullId.channel)),
+					MTP_int(position.fullId.msg))
+			)).done([=](const MTPUpdates &result) {
+				applyUpdates(result);
+				_feedReadRequests.remove(feed);
+			}).fail([=](const RPCError &error) {
+				_feedReadRequests.remove(feed);
+			}).send();
+			_feedReadRequests.emplace(feed, requestId);
+
+			i = _feedReadsDelayed.erase(i);
+		}
+	}
+	if (!_feedReadRequests.empty()) {
+		_feedReadTimer.callOnce(delay);
+	}
+}
+
 void ApiWrap::sendReadRequest(not_null<PeerData*> peer, MsgId upTo) {
 	const auto requestId = [&] {
 		const auto finished = [=] {

Telegram/SourceFiles/apiwrap.h

@@ -226,6 +226,9 @@ public:
 	void shareContact(not_null<UserData*> user, const SendOptions &options);
 	void readServerHistory(not_null<History*> history);
 	void readServerHistoryForce(not_null<History*> history);
+	void readFeed(
+		not_null<Data::Feed*> feed,
+		Data::MessagePosition position);
 
 	void sendVoiceMessage(
 		QByteArray result,
@@ -399,6 +402,8 @@ private:
 		bool silent,
 		uint64 randomId);
 
+	void readFeeds();
+
 	not_null<AuthSession*> _session;
 
 	MessageDataRequests _messageDataRequests;
@@ -511,6 +516,7 @@ private:
 	};
 	base::flat_map<not_null<PeerData*>, ReadRequest> _readRequests;
 	base::flat_map<not_null<PeerData*>, MsgId> _readRequestsPending;
+
 	std::unique_ptr<TaskQueue> _fileLoader;
 	base::flat_map<uint64, std::shared_ptr<SendingAlbum>> _sendingAlbums;
 
@@ -518,4 +524,8 @@ private:
 
 	rpl::event_stream<uint64> _stickerSetInstalled;
 
+	base::flat_map<not_null<Data::Feed*>, TimeMs> _feedReadsDelayed;
+	base::flat_map<not_null<Data::Feed*>, mtpRequestId> _feedReadRequests;
+	base::Timer _feedReadTimer;
+
 };

Telegram/SourceFiles/history/feed/history_feed_section.cpp

@@ -27,6 +27,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_session.h"
 #include "storage/storage_feed_messages.h"
 #include "mainwidget.h"
+#include "apiwrap.h"
 #include "auth_session.h"
 #include "styles/style_widgets.h"
 #include "styles/style_history.h"
@@ -241,6 +242,40 @@ void Widget::listSelectionChanged(HistoryView::SelectedItems &&items) {
 	_topBar->showSelected(state);
 }
 
+void Widget::listVisibleItemsChanged(HistoryItemsList &&items) {
+	const auto reversed = ranges::view::reverse(items);
+	const auto good = ranges::find_if(reversed, [](auto item) {
+		return IsServerMsgId(item->id);
+	});
+	if (good != end(reversed)) {
+		Auth().api().readFeed(_feed, (*good)->position());
+	}
+}
+
+base::optional<int> Widget::listUnreadBarView(
+		const std::vector<not_null<Element*>> &elements) {
+	const auto position = _feed->unreadPosition();
+	if (!position || elements.empty()) {
+		return base::none;
+	}
+	const auto minimal = ranges::upper_bound(
+		elements,
+		position,
+		std::less<>(),
+		[](auto view) { return view->data()->position(); });
+	if (minimal == end(elements)) {
+		return base::none;
+	}
+	const auto view = *minimal;
+	const auto unreadMessagesHeight = elements.back()->y()
+		+ elements.back()->height()
+		- view->y();
+	if (unreadMessagesHeight < _scroll->height()) {
+		return base::none;
+	}
+	return base::make_optional(int(minimal - begin(elements)));
+}
+
 std::unique_ptr<Window::SectionMemento> Widget::createMemento() {
 	auto result = std::make_unique<Memento>(_feed);
 	saveState(result.get());
@@ -272,7 +307,9 @@ void Widget::resizeEvent(QResizeEvent *e) {
 void Widget::updateControlsGeometry() {
 	const auto contentWidth = width();
 
-	const auto newScrollTop = _scroll->scrollTop() + topDelta();
+	const auto newScrollTop = _scroll->isHidden()
+		? base::none
+		: base::make_optional(_scroll->scrollTop() + topDelta());
 	_topBar->resizeToWidth(contentWidth);
 	_topBarShadow->resize(contentWidth, st::lineWidth);
 
@@ -282,14 +319,14 @@ void Widget::updateControlsGeometry() {
 		- _showNext->height();
 	const auto scrollSize = QSize(contentWidth, scrollHeight);
 	if (_scroll->size() != scrollSize) {
+		_skipScrollEvent = true;
 		_scroll->resize(scrollSize);
 		_inner->resizeToWidth(scrollSize.width(), _scroll->height());
-		//_inner->restoreScrollPosition();
+		_skipScrollEvent = false;
 	}
-
 	if (!_scroll->isHidden()) {
-		if (topDelta()) {
-			_scroll->scrollToY(newScrollTop);
+		if (newScrollTop) {
+			_scroll->scrollToY(*newScrollTop);
 		}
 		updateInnerVisibleArea();
 	}
@@ -320,12 +357,16 @@ void Widget::paintEvent(QPaintEvent *e) {
 }
 
 void Widget::onScroll() {
+	if (_skipScrollEvent) {
+		return;
+	}
 	updateInnerVisibleArea();
 }
 
 void Widget::updateInnerVisibleArea() {
 	const auto scrollTop = _scroll->scrollTop();
 	_inner->setVisibleTopBottom(scrollTop, scrollTop + _scroll->height());
+
 }
 
 void Widget::showAnimatedHook(

Telegram/SourceFiles/history/feed/history_feed_section.h

@@ -21,6 +21,7 @@ class FlatButton;
 namespace HistoryView {
 class ListWidget;
 class TopBarWidget;
+class Element;
 } // namespace HistoryView
 
 namespace HistoryFeed {
@@ -31,6 +32,8 @@ class Widget final
 	: public Window::SectionWidget
 	, public HistoryView::ListDelegate {
 public:
+	using Element = HistoryView::Element;
+
 	Widget(
 		QWidget *parent,
 		not_null<Window::Controller*> controller,
@@ -75,6 +78,9 @@ public:
 		not_null<HistoryItem*> second) override;
 	void listSelectionChanged(
 		HistoryView::SelectedItems &&items) override;
+	void listVisibleItemsChanged(HistoryItemsList &&items) override;
+	base::optional<int> listUnreadBarView(
+		const std::vector<not_null<Element*>> &elements) override;
 
 protected:
 	void resizeEvent(QResizeEvent *e) override;
@@ -104,6 +110,7 @@ private:
 	object_ptr<HistoryView::TopBarWidget> _topBar;
 	object_ptr<Ui::PlainShadow> _topBarShadow;
 	object_ptr<Ui::FlatButton> _showNext;
+	bool _skipScrollEvent = false;
 	bool _undefinedAroundPosition = false;
 
 };

Telegram/SourceFiles/history/view/history_view_element.cpp

@@ -57,11 +57,14 @@ TextSelection ShiftItemSelection(
 	return ShiftItemSelection(selection, byText.length());
 }
 
-void UnreadBar::init(int count) {
+void UnreadBar::init(int newCount) {
 	if (freezed) {
 		return;
 	}
-	text = lng_unread_bar(lt_count, count);
+	count = newCount;
+	text = (count == kCountUnknown)
+		? lang(lng_unread_bar_some)
+		: lng_unread_bar(lt_count, count);
 	width = st::semiboldFont->width(text);
 }
 
@@ -311,8 +314,6 @@ void Element::destroyUnreadBar() {
 }
 
 void Element::setUnreadBarCount(int count) {
-	Expects(count > 0);
-
 	const auto changed = AddComponents(UnreadBar::Bit());
 	const auto bar = Get<UnreadBar>();
 	if (bar->freezed) {

Telegram/SourceFiles/history/view/history_view_element.h

@@ -61,15 +61,18 @@ TextSelection ShiftItemSelection(
 // Any HistoryView::Element can have this Component for
 // displaying the unread messages bar above the message.
 struct UnreadBar : public RuntimeComponent<UnreadBar, Element> {
-	void init(int count);
+	void init(int newCount);
 
 	static int height();
 	static int marginTop();
 
 	void paint(Painter &p, int y, int w) const;
 
+	static constexpr auto kCountUnknown = std::numeric_limits<int>::max();
+
 	QString text;
 	int width = 0;
+	int count = 0;
 
 	// If unread bar is freezed the new messages do not
 	// increment the counter displayed by this bar.
@@ -150,8 +153,6 @@ public:
 
 	bool computeIsAttachToPrevious(not_null<Element*> previous);
 
-	// count > 0 - creates the unread bar if necessary and
-	// sets unread messages count if bar is not freezed yet
 	void setUnreadBarCount(int count);
 	void destroyUnreadBar();
 

Telegram/SourceFiles/history/view/history_view_list_widget.cpp

@@ -238,6 +238,7 @@ ListWidget::ListWidget(
 , _context(_delegate->listContext())
 , _itemAverageHeight(itemMinimalHeight())
 , _scrollDateCheck([this] { scrollDateCheck(); })
+, _applyUpdatedScrollState([this] { applyUpdatedScrollState(); })
 , _selectEnabled(_delegate->listAllowsMultiSelect()) {
 	setMouseTracking(true);
 	_scrollDateHideTimer.setCallback([this] { scrollDateHideByTimer(); });
@@ -320,10 +321,21 @@ void ListWidget::refreshRows() {
 	updateAroundPositionFromRows();
 
 	updateItemsGeometry();
+	checkUnreadBarCreation();
 	restoreScrollState();
 	mouseActionUpdate(QCursor::pos());
 }
 
+void ListWidget::checkUnreadBarCreation() {
+	if (!_unreadBarElement) {
+		if (const auto index = _delegate->listUnreadBarView(_items)) {
+			_unreadBarElement = _items[*index].get();
+			_unreadBarElement->setUnreadBarCount(UnreadBar::kCountUnknown);
+			refreshAttachmentsAtIndex(*index);
+		}
+	}
+}
+
 void ListWidget::saveScrollState() {
 	if (!_scrollTopState.item) {
 		_scrollTopState = countScrollState();
@@ -331,9 +343,16 @@ void ListWidget::saveScrollState() {
 }
 
 void ListWidget::restoreScrollState() {
-	if (_items.empty() || !_scrollTopState.item) {
+	if (_items.empty()) {
 		return;
 	}
+	if (!_scrollTopState.item) {
+		if (!_unreadBarElement) {
+			return;
+		}
+		_scrollTopState.item = _unreadBarElement->data()->position();
+		_scrollTopState.shift = st::lineWidth + st::historyUnreadBarMargin;
+	}
 	const auto index = findNearestItem(_scrollTopState.item);
 	if (index >= 0) {
 		const auto view = _items[index];
@@ -393,21 +412,57 @@ int ListWidget::findNearestItem(Data::MessagePosition position) const {
 		: int(after - begin(_items));
 }
 
+HistoryItemsList ListWidget::collectVisibleItems() const {
+	auto result = HistoryItemsList();
+	const auto from = std::lower_bound(
+		begin(_items),
+		end(_items),
+		_visibleTop,
+		[this](auto &elem, int top) {
+			return this->itemTop(elem) + elem->height() <= top;
+		});
+	const auto to = std::lower_bound(
+		begin(_items),
+		end(_items),
+		_visibleBottom,
+		[this](auto &elem, int bottom) {
+			return this->itemTop(elem) < bottom;
+		});
+	result.reserve(to - from);
+	for (auto i = from; i != to; ++i) {
+		result.push_back((*i)->data());
+	}
+	return result;
+}
+
 void ListWidget::visibleTopBottomUpdated(
 		int visibleTop,
 		int visibleBottom) {
-	auto scrolledUp = (visibleTop < _visibleTop);
+	if (!(visibleTop < visibleBottom)) {
+		return;
+	}
+
+	const auto initializing = !(_visibleTop < _visibleBottom);
+	const auto scrolledUp = (visibleTop < _visibleTop);
 	_visibleTop = visibleTop;
 	_visibleBottom = visibleBottom;
 
+	if (initializing) {
+		checkUnreadBarCreation();
+	}
 	updateVisibleTopItem();
-	checkMoveToOtherViewer();
 	if (scrolledUp) {
 		_scrollDateCheck.call();
 	} else {
 		scrollDateHideByTimer();
 	}
 	_controller->floatPlayerAreaUpdated().notify(true);
+	_applyUpdatedScrollState.call();
+}
+
+void ListWidget::applyUpdatedScrollState() {
+	checkMoveToOtherViewer();
+	_delegate->listVisibleItemsChanged(collectVisibleItems());
 }
 
 void ListWidget::updateVisibleTopItem() {
@@ -938,11 +993,16 @@ void ListWidget::updateItemsGeometry() {
 }
 
 void ListWidget::updateSize() {
-	TWidget::resizeToWidth(width());
-	restoreScrollPosition();
+	resizeToWidth(width(), _minHeight);
 	updateVisibleTopItem();
 }
 
+void ListWidget::resizeToWidth(int newWidth, int minHeight) {
+	_minHeight = minHeight;
+	TWidget::resizeToWidth(newWidth);
+	restoreScrollPosition();
+}
+
 int ListWidget::resizeGetHeight(int newWidth) {
 	update();
 
@@ -963,7 +1023,9 @@ int ListWidget::resizeGetHeight(int newWidth) {
 	}
 	_itemsWidth = newWidth;
 	_itemsHeight = newHeight;
-	_itemsTop = (_minHeight > _itemsHeight + st::historyPaddingBottom) ? (_minHeight - _itemsHeight - st::historyPaddingBottom) : 0;
+	_itemsTop = (_minHeight > _itemsHeight + st::historyPaddingBottom)
+		? (_minHeight - _itemsHeight - st::historyPaddingBottom)
+		: 0;
 	return _itemsTop + _itemsHeight + st::historyPaddingBottom;
 }
 
@@ -2131,6 +2193,18 @@ void ListWidget::viewReplaced(not_null<const Element*> was, Element *now) {
 	if (_visibleTopItem == was) _visibleTopItem = now;
 	if (_scrollDateLastItem == was) _scrollDateLastItem = now;
 	if (_overElement == was) _overElement = now;
+	if (_unreadBarElement == was) {
+		const auto bar = _unreadBarElement->Get<UnreadBar>();
+		const auto count = bar ? bar->count : 0;
+		const auto freezed = bar ? bar->freezed : false;
+		_unreadBarElement = now;
+		if (now && count) {
+			_unreadBarElement->setUnreadBarCount(count);
+			if (freezed) {
+				_unreadBarElement->setUnreadBarFreezed();
+			}
+		}
+	}
 }
 
 void ListWidget::itemRemoved(not_null<const HistoryItem*> item) {

Telegram/SourceFiles/history/view/history_view_list_widget.h

@@ -61,6 +61,9 @@ public:
 		not_null<HistoryItem*> first,
 		not_null<HistoryItem*> second) = 0;
 	virtual void listSelectionChanged(SelectedItems &&items) = 0;
+	virtual void listVisibleItemsChanged(HistoryItemsList &&items) = 0;
+	virtual base::optional<int> listUnreadBarView(
+		const std::vector<not_null<Element*>> &elements) = 0;
 
 };
 
@@ -127,10 +130,7 @@ public:
 	// Set the correct scroll position after being resized.
 	void restoreScrollPosition();
 
-	void resizeToWidth(int newWidth, int minHeight) {
-		_minHeight = minHeight;
-		return TWidget::resizeToWidth(newWidth);
-	}
+	void resizeToWidth(int newWidth, int minHeight);
 
 	void saveState(not_null<ListMemento*> memento);
 	void restoreState(not_null<ListMemento*> memento);
@@ -264,6 +264,7 @@ private:
 	Element *strictFindItemByY(int y) const;
 	int findNearestItem(Data::MessagePosition position) const;
 	void viewReplaced(not_null<const Element*> was, Element *now);
+	HistoryItemsList collectVisibleItems() const;
 
 	void checkMoveToOtherViewer();
 	void updateVisibleTopItem();
@@ -352,6 +353,8 @@ private:
 	TextSelection computeRenderSelection(
 		not_null<const SelectedMap*> selected,
 		not_null<const Element*> view) const;
+	void checkUnreadBarCreation();
+	void applyUpdatedScrollState();
 
 	// This function finds all history items that are displayed and calls template method
 	// for each found message (in given direction) in the passed history with passed top offset.
@@ -409,6 +412,9 @@ private:
 	base::Timer _scrollDateHideTimer;
 	Element *_scrollDateLastItem = nullptr;
 	int _scrollDateLastItemTop = 0;
+	SingleQueuedInvokation _applyUpdatedScrollState;
+
+	Element *_unreadBarElement = nullptr;
 
 	MouseAction _mouseAction = MouseAction::None;
 	TextSelectType _mouseSelectType = TextSelectType::Letters;

Telegram/SourceFiles/mainwidget.cpp

@@ -18,6 +18,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_drafts.h"
 #include "data/data_session.h"
 #include "data/data_media_types.h"
+#include "data/data_feed.h"
 #include "ui/special_buttons.h"
 #include "ui/widgets/buttons.h"
 #include "ui/widgets/shadow.h"
@@ -4676,7 +4677,17 @@ void MainWidget::feedUpdate(const MTPUpdate &update) {
 	case mtpc_updateReadFeed: {
 		const auto &d = update.c_updateReadFeed();
 		const auto feedId = d.vfeed_id.v;
-		// #TODO feeds
+		if (const auto feed = Auth().data().feedLoaded(feedId)) {
+			feed->setUnreadPosition(
+				Data::FeedPositionFromMTP(d.vmax_position));
+			if (d.has_unread_count() && d.has_unread_muted_count()) {
+				feed->setUnreadCounts(
+					d.vunread_count.v,
+					d.vunread_muted_count.v);
+			} else {
+				Auth().api().requestDialogEntry(feed);
+			}
+		}
 	} break;
 
 	// Deleted messages.