Implement premium lock of similar channels.

Telegram/CMakeLists.txt

@@ -899,6 +899,8 @@ PRIVATE
     info/profile/info_profile_widget.h
     info/settings/info_settings_widget.cpp
     info/settings/info_settings_widget.h
+    info/similar_channels/info_similar_channels_widget.cpp
+    info/similar_channels/info_similar_channels_widget.h
     info/statistics/info_statistics_common.h
     info/statistics/info_statistics_inner_widget.cpp
     info/statistics/info_statistics_inner_widget.h

Telegram/Resources/langs/lang.strings

@@ -1175,6 +1175,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 "lng_profile_bot_privacy" = "Bot Privacy Policy";
 "lng_profile_common_groups#one" = "{count} group in common";
 "lng_profile_common_groups#other" = "{count} groups in common";
+"lng_profile_similar_channels#one" = "{count} similar channel";
+"lng_profile_similar_channels#other" = "{count} similar channels";
 "lng_profile_participants_section" = "Members";
 "lng_profile_subscribers_section" = "Subscribers";
 "lng_profile_add_contact" = "Add Contact";
@@ -1686,6 +1688,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 "lng_similar_channels_premium_all#one" = "Subscribe to {link} to unlock up to **{count}** similar channel.";
 "lng_similar_channels_premium_all#other" = "Subscribe to {link} to unlock up to **{count}** similar channels.";
 "lng_similar_channels_premium_all_link" = "Telegram Premium";
+"lng_similar_channels_show_more" = "Show more channels";
 
 "lng_premium_gift_duration_months#one" = "for {count} month";
 "lng_premium_gift_duration_months#other" = "for {count} months";

Telegram/SourceFiles/api/api_chat_participants.cpp

@@ -227,7 +227,9 @@ void ApplyBotsList(
 			}
 		}
 		if constexpr (MTPDmessages_chatsSlice::Is<decltype(data)>()) {
-			result.more = data.vcount().v - data.vchats().v.size();
+			if (channel->session().premiumPossible()) {
+				result.more = data.vcount().v - data.vchats().v.size();
+			}
 		}
 	});
 	return result;

Telegram/SourceFiles/data/data_premium_limits.cpp

@@ -29,6 +29,18 @@ int PremiumLimits::channelsCurrent() const {
 		: channelsDefault();
 }
 
+int PremiumLimits::similarChannelsDefault() const {
+	return appConfigLimit("recommended_channels_limit_default", 10);
+}
+int PremiumLimits::similarChannelsPremium() const {
+	return appConfigLimit("recommended_channels_limit_premium", 100);
+}
+int PremiumLimits::similarChannelsCurrent() const {
+	return isPremium()
+		? channelsPremium()
+		: channelsDefault();
+}
+
 int PremiumLimits::gifsDefault() const {
 	return appConfigLimit("saved_gifs_limit_default", 200);
 }

Telegram/SourceFiles/data/data_premium_limits.h

@@ -21,6 +21,10 @@ public:
 	[[nodiscard]] int channelsPremium() const;
 	[[nodiscard]] int channelsCurrent() const;
 
+	[[nodiscard]] int similarChannelsDefault() const;
+	[[nodiscard]] int similarChannelsPremium() const;
+	[[nodiscard]] int similarChannelsCurrent() const;
+
 	[[nodiscard]] int gifsDefault() const;
 	[[nodiscard]] int gifsPremium() const;
 	[[nodiscard]] int gifsCurrent() const;

Telegram/SourceFiles/history/view/media/history_view_similar_channels.cpp

@@ -12,6 +12,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "boxes/peer_lists_box.h"
 #include "core/click_handler_types.h"
 #include "data/data_channel.h"
+#include "data/data_premium_limits.h"
 #include "data/data_session.h"
 #include "dialogs/ui/dialogs_stories_content.h"
 #include "dialogs/ui/dialogs_stories_list.h"
@@ -19,9 +20,10 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "history/view/history_view_cursor_state.h"
 #include "history/history.h"
 #include "history/history_item.h"
+#include "info/similar_channels/info_similar_channels_widget.h"
+#include "info/info_controller.h"
+#include "info/info_memento.h"
 #include "lang/lang_keys.h"
-#include "main/main_account.h"
-#include "main/main_app_config.h"
 #include "main/main_session.h"
 #include "settings/settings_premium.h"
 #include "ui/chat/chat_style.h"
@@ -37,73 +39,19 @@ namespace {
 
 using Channels = Api::ChatParticipants::Channels;
 
-class SimilarChannelsController final : public PeerListController {
-public:
-	SimilarChannelsController(
-		not_null<Window::SessionController*> controller,
-		Channels channels);
-
-	void prepare() override;
-	void loadMoreRows() override;
-	void rowClicked(not_null<PeerListRow*> row) override;
-	Main::Session &session() const override;
-
-private:
-	const not_null<Window::SessionController*> _controller;
-	const Channels _channels;
-
-};
-
-SimilarChannelsController::SimilarChannelsController(
-	not_null<Window::SessionController*> controller,
-	Channels channels)
-: _controller(controller)
-, _channels(std::move(channels)) {
-}
-
-void SimilarChannelsController::prepare() {
-	for (const auto &channel : _channels.list) {
-		auto row = std::make_unique<PeerListRow>(channel);
-		if (const auto count = channel->membersCount(); count > 1) {
-			row->setCustomStatus(tr::lng_chat_status_subscribers(
-				tr::now,
-				lt_count,
-				count));
-		}
-		delegate()->peerListAppendRow(std::move(row));
-	}
-	delegate()->peerListRefreshRows();
-}
-
-void SimilarChannelsController::loadMoreRows() {
-}
-
-void SimilarChannelsController::rowClicked(not_null<PeerListRow*> row) {
-	const auto other = ClickHandlerContext{
-		.sessionWindow = _controller,
-		.show = _controller->uiShow(),
-	};
-	row->peer()->openLink()->onClick({
-		Qt::LeftButton,
-		QVariant::fromValue(other)
-	});
-}
-
-Main::Session &SimilarChannelsController::session() const {
-	return _channels.list.front()->session();
-}
-
-[[nodiscard]] object_ptr<Ui::BoxContent> SimilarChannelsBox(
-		not_null<Window::SessionController*> controller,
-		const Channels &channels) {
-	const auto initBox = [=](not_null<PeerListBox*> box) {
-		box->setTitle(tr::lng_similar_channels_title());
-		box->addButton(tr::lng_close(), [=] { box->closeBox(); });
-	};
-	return Box<PeerListBox>(
-		std::make_unique<SimilarChannelsController>(controller, channels),
-		initBox);
-}
+//void SimilarChannelsController::prepare() {
+//	for (const auto &channel : _channels.list) {
+//		auto row = std::make_unique<PeerListRow>(channel);
+//		if (const auto count = channel->membersCount(); count > 1) {
+//			row->setCustomStatus(tr::lng_chat_status_subscribers(
+//				tr::now,
+//				lt_count,
+//				count));
+//		}
+//		delegate()->peerListAppendRow(std::move(row));
+//	}
+//	delegate()->peerListRefreshRows();
+//}
 
 [[nodiscard]] ClickHandlerPtr MakeViewAllLink(
 		not_null<ChannelData*> channel,
@@ -113,10 +61,8 @@ Main::Session &SimilarChannelsController::session() const {
 		if (const auto strong = my.sessionWindow.get()) {
 			Assert(channel != nullptr);
 			if (promoForNonPremium && !channel->session().premium()) {
-				const auto account = &channel->session().account();
-				const auto upto = account->appConfig().get<int>(
-					u"recommended_channels_limit_premium"_q,
-					100);
+				const auto upto = Data::PremiumLimits(
+					&channel->session()).similarChannelsPremium();
 				Settings::ShowPremiumPromoToast(
 					strong->uiShow(),
 					tr::lng_similar_channels_premium_all(
@@ -137,7 +83,10 @@ Main::Session &SimilarChannelsController::session() const {
 			if (list.list.empty()) {
 				return;
 			}
-			strong->show(SimilarChannelsBox(strong, list));
+			strong->showSection(
+				std::make_shared<Info::Memento>(
+					channel,
+					Info::Section::Type::SimilarChannels));
 		}
 	});
 }
@@ -217,6 +166,7 @@ void SimilarChannels::draw(Painter &p, const PaintContext &context) const {
 	const auto padding = st::chatSimilarChannelPadding;
 	p.setClipRect(geometry);
 	_hasHeavyPart = 1;
+	validateLastPremiumLock();
 	const auto drawOne = [&](const Channel &channel) {
 		const auto geometry = channel.geometry.translated(-_scrollLeft, 0);
 		const auto right = geometry.x() + geometry.width();
@@ -394,12 +344,68 @@ void SimilarChannels::draw(Painter &p, const PaintContext &context) const {
 	p.setClipping(false);
 }
 
+void SimilarChannels::validateLastPremiumLock() const {
+	if (_channels.empty()) {
+		return;
+	}
+	if (!_moreThumbnailsValid) {
+		_moreThumbnailsValid = 1;
+		fillMoreThumbnails();
+	}
+	const auto &last = _channels.back();
+	if (!last.more) {
+		return;
+	}
+	const auto premium = history()->session().premium();
+	const auto locked = !premium && history()->session().premiumPossible();
+	if (last.moreLocked == locked) {
+		return;
+	}
+	last.moreLocked = locked ? 1 : 0;
+	last.counterBgValid = 0;
+}
+
+void SimilarChannels::fillMoreThumbnails() const {
+	const auto channel = parent()->history()->peer->asChannel();
+	Assert(channel != nullptr);
+
+	_moreThumbnails = {};
+	const auto api = &channel->session().api();
+	const auto &similar = api->chatParticipants().similar(channel);
+	for (auto i = 0, count = int(_moreThumbnails.size()); i != count; ++i) {
+		if (similar.list.size() <= _channels.size() + i) {
+			break;
+		}
+		_moreThumbnails[i] = Dialogs::Stories::MakeUserpicThumbnail(
+			similar.list[_channels.size() + i]);
+	}
+}
+
 void SimilarChannels::validateCounterBg(const Channel &channel) const {
 	if (channel.counterBgValid) {
 		return;
 	}
 	channel.counterBgValid = 1;
+
 	const auto photo = st::chatSimilarChannelPhoto;
+	const auto inner = QRect(0, 0, photo, photo);
+	const auto outer = inner.marginsAdded(st::chatSimilarChannelPadding);
+	const auto length = st::chatSimilarBadgeFont->width(channel.counter);
+	const auto contents = length
+		+ (!channel.more
+			? st::chatSimilarBadgeIcon.width()
+			: channel.moreLocked
+			? st::chatSimilarLockedIcon.width()
+			: 0);
+	const auto delta = (outer.width() - contents) / 2;
+	const auto badge = QRect(
+		delta,
+		st::chatSimilarBadgeTop,
+		outer.width() - 2 * delta,
+		st::chatSimilarBadgeFont->height);
+	channel.counterRect = badge.marginsAdded(
+		st::chatSimilarBadgePadding);
+
 	const auto width = channel.counterRect.width();
 	const auto height = channel.counterRect.height();
 	const auto ratio = style::DevicePixelRatio();
@@ -517,8 +523,9 @@ QSize SimilarChannels::countOptimalSize() {
 	const auto api = &channel->session().api();
 	api->chatParticipants().loadSimilarChannels(channel);
 	const auto premium = channel->session().premium();
-	const auto similar = api->chatParticipants().similar(channel);
+	const auto &similar = api->chatParticipants().similar(channel);
 	_empty = similar.list.empty() ? 1 : 0;
+	_moreThumbnailsValid = 0;
 	using Flag = ChannelDataFlag;
 	_toggled = (channel->flags() & Flag::SimilarExpanded) ? 1 : 0;
 	if (_empty || !_toggled) {
@@ -532,9 +539,8 @@ QSize SimilarChannels::countOptimalSize() {
 	const auto photo = st::chatSimilarChannelPhoto;
 	const auto inner = QRect(0, 0, photo, photo);
 	const auto outer = inner.marginsAdded(st::chatSimilarChannelPadding);
-	const auto limit = channel->session().account().appConfig().get<int>(
-		u"recommended_channels_limit_default"_q,
-		10);
+	const auto limit = Data::PremiumLimits(
+		&channel->session()).similarChannelsDefault();
 	const auto take = (similar.more > 0 || similar.list.size() > 2 * limit)
 		? limit
 		: int(similar.list.size());
@@ -565,34 +571,11 @@ QSize SimilarChannels::countOptimalSize() {
 			? moreCounter :
 			channel->membersCount();
 		if (moreCounter || counter > 1) {
-			const auto text = (moreCounter ? u"+"_q : QString())
+			last.counter = (moreCounter ? u"+"_q : QString())
 				+ Lang::FormatCountToShort(counter).string;
-			const auto length = st::chatSimilarBadgeFont->width(text);
-			const auto width = length
-				+ (!moreCounter
-					? st::chatSimilarBadgeIcon.width()
-					: !premium
-					? st::chatSimilarLockedIcon.width()
-					: 0);
-			const auto delta = (outer.width() - width) / 2;
-			const auto badge = QRect(
-				delta,
-				st::chatSimilarBadgeTop,
-				outer.width() - 2 * delta,
-				st::chatSimilarBadgeFont->height);
-			last.counter = text;
-			last.counterRect = badge.marginsAdded(
-				st::chatSimilarBadgePadding);
 		}
 		x += outer.width() + skip;
 	}
-	for (auto i = 0, count = int(_moreThumbnails.size()); i != count; ++i) {
-		if (similar.list.size() <= _channels.size() + i) {
-			break;
-		}
-		_moreThumbnails[i] = Dialogs::Stories::MakeUserpicThumbnail(
-			similar.list[_channels.size() + i]);
-	}
 	_title = tr::lng_similar_channels_title(tr::now);
 	_titleWidth = st::chatSimilarTitle->width(_title);
 	_viewAll = tr::lng_similar_channels_view_all(tr::now);
@@ -604,7 +587,7 @@ QSize SimilarChannels::countOptimalSize() {
 	const auto bubble = full.marginsAdded(st::chatSimilarPadding);
 	_fullWidth = bubble.width();
 	const auto titleSkip = st::chatSimilarTitlePosition.x();
-	const auto min = _titleWidth + 2 * titleSkip;
+	const auto min = int(_titleWidth) + 2 * titleSkip;
 	const auto limited = std::max(
 		std::min(int(_fullWidth), st::chatSimilarWidthMax),
 		min);

Telegram/SourceFiles/history/view/media/history_view_similar_channels.h

@@ -65,16 +65,18 @@ private:
 		std::shared_ptr<Thumbnail> thumbnail;
 		ClickHandlerPtr link;
 		QString counter;
-		QRect counterRect;
+		mutable QRect counterRect;
 		mutable QImage counterBg;
 		mutable std::unique_ptr<Ui::RippleAnimation> ripple;
 		uint32 more : 29 = 0;
-		uint32 moreLocked : 1 = 0;
+		mutable uint32 moreLocked : 1 = 0;
 		mutable uint32 subscribed : 1 = 0;
 		mutable uint32 counterBgValid : 1 = 0;
 	};
 
 	void ensureCacheReady(QSize size) const;
+	void validateLastPremiumLock() const;
+	void fillMoreThumbnails() const;
 	void validateCounterBg(const Channel &channel) const;
 	[[nodiscard]] ClickHandlerPtr ensureToggleLink() const;
 
@@ -85,7 +87,8 @@ private:
 	mutable QImage _roundedCache;
 	mutable std::array<QImage, 4> _roundedCorners;
 	mutable QPoint _lastPoint;
-	int _titleWidth = 0;
+	uint32 _titleWidth : 15 = 0;
+	mutable uint32 _moreThumbnailsValid : 1 = 0;
 	uint32 _viewAllWidth : 15 = 0;
 	uint32 _fullWidth : 15 = 0;
 	uint32 _empty : 1 = 0;
@@ -96,7 +99,7 @@ private:
 	mutable uint32 _hasHeavyPart : 1 = 0;
 
 	std::vector<Channel> _channels;
-	std::array<std::shared_ptr<Thumbnail>, 2> _moreThumbnails;
+	mutable std::array<std::shared_ptr<Thumbnail>, 2> _moreThumbnails;
 	mutable ClickHandlerPtr _viewAllLink;
 	mutable ClickHandlerPtr _toggleLink;
 

Telegram/SourceFiles/info/info.style

@@ -395,6 +395,7 @@ infoIconMediaFile: icon {{ "info/info_media_file", infoIconFg }};
 infoIconMediaAudio: icon {{ "info/info_media_audio", infoIconFg }};
 infoIconMediaLink: icon {{ "info/info_media_link", infoIconFg }};
 infoIconMediaGroup: icon {{ "info/info_common_groups", infoIconFg }};
+infoIconMediaChannel: icon {{ "menu/channel", infoIconFg, point(4px, 4px) }};
 infoIconMediaVoice: icon {{ "info/info_media_voice", infoIconFg }};
 infoIconMediaStories: icon {{ "info/info_media_stories", infoIconFg }};
 infoIconMediaStoriesArchive: icon {{ "info/info_stories_archive", infoIconFg }};
@@ -530,7 +531,7 @@ infoMediaLeft: 3px;
 infoMediaMargin: margins(0px, 6px, 0px, 2px);
 infoMediaMinGridSize: 90px;
 
-infoCommonGroupsMargin: margins(0px, 13px, 0px, 2px);
+infoCommonGroupsMargin: margins(0px, 2px, 0px, 2px);
 infoCommonGroupsListItem: PeerListItem(defaultPeerListItem) {
 	height: 52px;
 	photoSize: 40px;
@@ -952,3 +953,14 @@ shortInfoCover: ShortInfoCover {
 }
 
 permissionsExpandIcon: icon{{ "info/edit/expand_arrow_small", windowBoldFg }};
+
+similarChannelsLockOverlap: 58px;
+similarChannelsLockFade: 58px;
+similarChannelsLock: defaultActiveButton;
+similarChannelsLockPadding: margins(12px, 12px, 12px, 12px);
+similarChannelsLockAbout: FlatLabel(defaultFlatLabel) {
+	textFg: windowSubTextFg;
+	align: align(top);
+	minWidth: 128px;
+}
+similarChannelsLockAboutPadding: margins(12px, 12px, 12px, 12px);

Telegram/SourceFiles/info/info_controller.h

@@ -125,6 +125,7 @@ public:
 		Profile,
 		Media,
 		CommonGroups,
+		SimilarChannels,
 		Members,
 		Settings,
 		Downloads,

Telegram/SourceFiles/info/info_memento.cpp

@@ -12,6 +12,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "info/members/info_members_widget.h"
 #include "info/common_groups/info_common_groups_widget.h"
 #include "info/settings/info_settings_widget.h"
+#include "info/similar_channels/info_similar_channels_widget.h"
 #include "info/polls/info_polls_results_widget.h"
 #include "info/info_section_widget.h"
 #include "info/info_layer_widget.h"
@@ -141,6 +142,9 @@ std::shared_ptr<ContentMemento> Memento::DefaultContent(
 			section.mediaType());
 	case Section::Type::CommonGroups:
 		return std::make_shared<CommonGroups::Memento>(peer->asUser());
+	case Section::Type::SimilarChannels:
+		return std::make_shared<SimilarChannels::Memento>(
+			peer->asChannel());
 	case Section::Type::Members:
 		return std::make_shared<Members::Memento>(
 			peer,

Telegram/SourceFiles/info/media/info_media_buttons.h

@@ -20,6 +20,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "ui/wrap/vertical_layout.h"
 #include "ui/widgets/buttons.h"
 #include "window/window_session_controller.h"
+#include "data/data_channel.h"
 #include "data/data_user.h"
 #include "styles/style_info.h"
 
@@ -120,7 +121,33 @@ inline auto AddCommonGroupsButton(
 		tracker)->entity();
 	result->addClickHandler([=] {
 		navigation->showSection(
-			std::make_shared<Info::Memento>(user, Section::Type::CommonGroups));
+			std::make_shared<Info::Memento>(
+				user,
+				Section::Type::CommonGroups));
+	});
+	return result;
+};
+
+inline auto AddSimilarChannelsButton(
+		Ui::VerticalLayout *parent,
+		not_null<Window::SessionNavigation*> navigation,
+		not_null<ChannelData*> channel,
+		Ui::MultiSlideTracker &tracker) {
+	auto result = AddCountedButton(
+		parent,
+		Profile::SimilarChannelsCountValue(channel),
+		[](int count) {
+			return tr::lng_profile_similar_channels(
+				tr::now,
+				lt_count,
+				count);
+		},
+		tracker)->entity();
+	result->addClickHandler([=] {
+		navigation->showSection(
+			std::make_shared<Info::Memento>(
+				channel,
+				Section::Type::SimilarChannels));
 	});
 	return result;
 };

Telegram/SourceFiles/info/profile/info_profile_inner_widget.cpp

@@ -186,6 +186,19 @@ object_ptr<Ui::RpWidget> InnerWidget::setupSharedMedia(
 			icon,
 			st::infoSharedMediaButtonIconPosition);
 	};
+	const auto addSimilarChannelsButton = [&](
+			not_null<ChannelData*> channel,
+			const style::icon &icon) {
+		auto result = Media::AddSimilarChannelsButton(
+			content,
+			_controller,
+			channel,
+			tracker);
+		object_ptr<Profile::FloatingIcon>(
+			result,
+			icon,
+			st::infoSharedMediaButtonIconPosition);
+	};
 	auto addStoriesButton = [&](
 			not_null<PeerData*> peer,
 			const style::icon &icon) {
@@ -211,8 +224,10 @@ object_ptr<Ui::RpWidget> InnerWidget::setupSharedMedia(
 	addMediaButton(MediaType::Link, st::infoIconMediaLink);
 	addMediaButton(MediaType::RoundVoiceFile, st::infoIconMediaVoice);
 	addMediaButton(MediaType::GIF, st::infoIconMediaGif);
-	if (auto user = _peer->asUser()) {
+	if (const auto user = _peer->asUser()) {
 		addCommonGroupsButton(user, st::infoIconMediaGroup);
+	} else if (const auto channel = _peer->asChannel()) {
+		addSimilarChannelsButton(channel, st::infoIconMediaChannel);
 	}
 
 	auto result = object_ptr<Ui::SlideWrap<Ui::VerticalLayout>>(

Telegram/SourceFiles/info/profile/info_profile_values.cpp

@@ -7,6 +7,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #include "info/profile/info_profile_values.h"
 
+#include "api/api_chat_participants.h"
+#include "apiwrap.h"
 #include "info/profile/info_profile_badge.h"
 #include "core/application.h"
 #include "core/click_handler_types.h"
@@ -520,6 +522,20 @@ rpl::producer<int> CommonGroupsCountValue(not_null<UserData*> user) {
 	});
 }
 
+rpl::producer<int> SimilarChannelsCountValue(
+		not_null<ChannelData*> channel) {
+	const auto participants = &channel->session().api().chatParticipants();
+	participants->loadSimilarChannels(channel);
+	return rpl::single(channel) | rpl::then(
+		participants->similarLoaded()
+	) | rpl::filter(
+		rpl::mappers::_1 == channel
+	) | rpl::map([=] {
+		const auto &similar = participants->similar(channel);
+		return int(similar.list.size()) + similar.more;
+	});
+}
+
 rpl::producer<bool> CanAddMemberValue(not_null<PeerData*> peer) {
 	if (const auto chat = peer->asChat()) {
 		return peer->session().changes().peerFlagsValue(

Telegram/SourceFiles/info/profile/info_profile_values.h

@@ -102,6 +102,8 @@ rpl::producer<not_null<PeerData*>> MigratedOrMeValue(
 	Storage::SharedMediaType type);
 [[nodiscard]] rpl::producer<int> CommonGroupsCountValue(
 	not_null<UserData*> user);
+[[nodiscard]] rpl::producer<int> SimilarChannelsCountValue(
+	not_null<ChannelData*> channel);
 [[nodiscard]] rpl::producer<bool> CanAddMemberValue(
 	not_null<PeerData*> peer);
 [[nodiscard]] rpl::producer<int> FullReactionsCountValue(

Telegram/SourceFiles/info/similar_channels/info_similar_channels_widget.cpp

@@ -0,0 +1,515 @@
+/*
+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 "info/similar_channels/info_similar_channels_widget.h"
+
+#include "api/api_chat_participants.h"
+#include "apiwrap.h"
+#include "boxes/peer_list_box.h"
+#include "data/data_channel.h"
+#include "data/data_peer_values.h"
+#include "data/data_premium_limits.h"
+#include "data/data_session.h"
+#include "info/info_controller.h"
+#include "main/main_session.h"
+#include "ui/text/text_utilities.h"
+#include "ui/widgets/buttons.h"
+#include "ui/widgets/scroll_area.h"
+#include "ui/widgets/tooltip.h"
+#include "ui/ui_utility.h"
+#include "lang/lang_keys.h"
+#include "settings/settings_premium.h"
+#include "window/window_session_controller.h"
+#include "styles/style_info.h"
+#include "styles/style_widgets.h"
+
+namespace Info::SimilarChannels {
+namespace {
+
+class ListController final : public PeerListController {
+public:
+	ListController(
+		not_null<Controller*> controller,
+		not_null<ChannelData*> channel);
+
+	Main::Session &session() const override;
+	void prepare() override;
+	void rowClicked(not_null<PeerListRow*> row) override;
+	void loadMoreRows() override;
+
+	std::unique_ptr<PeerListRow> createRestoredRow(
+			not_null<PeerData*> peer) override {
+		return createRow(peer);
+	}
+
+	std::unique_ptr<PeerListState> saveState() const override;
+	void restoreState(std::unique_ptr<PeerListState> state) override;
+
+	void setContentWidget(not_null<Ui::RpWidget*> widget);
+	[[nodiscard]] rpl::producer<int> unlockHeightValue() const;
+
+private:
+	std::unique_ptr<PeerListRow> createRow(not_null<PeerData*> peer);
+	void setupUnlock();
+	void rebuild();
+
+	struct SavedState : SavedStateBase {
+	};
+	const not_null<Controller*> _controller;
+	const not_null<ChannelData*> _channel;
+	Ui::RpWidget *_content = nullptr;
+	Ui::RpWidget *_unlock = nullptr;
+	rpl::variable<int> _unlockHeight;
+
+};
+
+ListController::ListController(
+	not_null<Controller*> controller,
+	not_null<ChannelData*> channel)
+: PeerListController()
+, _controller(controller)
+, _channel(channel) {
+}
+
+Main::Session &ListController::session() const {
+	return _channel->session();
+}
+
+std::unique_ptr<PeerListRow> ListController::createRow(
+		not_null<PeerData*> peer) {
+	auto result = std::make_unique<PeerListRow>(peer);
+	if (const auto channel = peer->asChannel()) {
+		if (const auto count = channel->membersCount(); count > 1) {
+			result->setCustomStatus(
+				tr::lng_chat_status_subscribers(tr::now, lt_count, count));
+		}
+	}
+	return result;
+}
+
+void ListController::prepare() {
+	delegate()->peerListSetTitle(tr::lng_similar_channels_title());
+
+	const auto participants = &_channel->session().api().chatParticipants();
+
+	Data::AmPremiumValue(
+		&_channel->session()
+	) | rpl::start_with_next([=] {
+		participants->loadSimilarChannels(_channel);
+		rebuild();
+	}, lifetime());
+
+	participants->similarLoaded(
+	) | rpl::filter(
+		rpl::mappers::_1 == _channel
+	) | rpl::start_with_next([=] {
+		rebuild();
+	}, lifetime());
+}
+
+void ListController::setContentWidget(not_null<Ui::RpWidget*> widget) {
+	_content = widget;
+}
+
+rpl::producer<int> ListController::unlockHeightValue() const {
+	return _unlockHeight.value();
+}
+
+void ListController::rebuild() {
+	const auto participants = &_channel->session().api().chatParticipants();
+	const auto &list = participants->similar(_channel);
+	for (const auto channel : list.list) {
+		if (!delegate()->peerListFindRow(channel->id.value)) {
+			delegate()->peerListAppendRow(createRow(channel));
+		}
+	}
+	if (!list.more
+		|| _channel->session().premium()
+		|| !_channel->session().premiumPossible()) {
+		delete base::take(_unlock);
+		_unlockHeight = 0;
+	} else if (!_unlock) {
+		setupUnlock();
+	}
+	delegate()->peerListRefreshRows();
+}
+
+void ListController::setupUnlock() {
+	Expects(_content != nullptr);
+
+	_unlock = Ui::CreateChild<Ui::RpWidget>(_content);
+	_unlock->show();
+
+	const auto button = Ui::CreateChild<Ui::RoundButton>(
+		_unlock,
+		tr::lng_similar_channels_show_more(),
+		st::similarChannelsLock);
+	button->setTextTransform(Ui::RoundButton::TextTransform::NoTransform);
+	button->setClickedCallback([=] {
+		const auto window = _controller->parentController();
+		::Settings::ShowPremium(window, u"similar_channels"_q);
+	});
+	const auto upto = Data::PremiumLimits(
+		&_channel->session()).similarChannelsPremium();
+	const auto about = Ui::CreateChild<Ui::FlatLabel>(
+		_unlock,
+		tr::lng_similar_channels_premium_all(
+			lt_count,
+			rpl::single(upto * 1.),
+			lt_link,
+			tr::lng_similar_channels_premium_all_link(
+			) | Ui::Text::ToBold() | Ui::Text::ToLink(),
+			Ui::Text::RichLangValue),
+		st::similarChannelsLockAbout);
+	about->setClickHandlerFilter([=](const auto &...) {
+		const auto window = _controller->parentController();
+		::Settings::ShowPremium(window, u"similar_channels"_q);
+		return false;
+	});
+
+	rpl::combine(
+		_content->sizeValue(),
+		tr::lng_similar_channels_show_more()
+	) | rpl::start_with_next([=](QSize size, const auto &) {
+		auto top = st::similarChannelsLockFade
+			+ st::similarChannelsLockPadding.top();
+		button->setGeometry(
+			st::similarChannelsLockPadding.left(),
+			top,
+			(size.width()
+				- st::similarChannelsLockPadding.left()
+				- st::similarChannelsLockPadding.right()),
+			button->height());
+		top += button->height() + st::similarChannelsLockPadding.bottom();
+
+		const auto minWidth = st::similarChannelsLockAbout.minWidth;
+		const auto maxWidth = std::max(
+			minWidth + 1,
+			(size.width()
+				- st::similarChannelsLockAboutPadding.left()
+				- st::similarChannelsLockAboutPadding.right()));
+		const auto countAboutHeight = [&](int width) {
+			about->resizeToWidth(width);
+			return about->height();
+		};
+		const auto desired = Ui::FindNiceTooltipWidth(
+			minWidth,
+			maxWidth,
+			countAboutHeight);
+		about->resizeToWidth(desired);
+		about->move((size.width() - about->width()) / 2, top);
+		top += about->height()
+			+ st::similarChannelsLockAboutPadding.bottom();
+		_unlock->setGeometry(0, size.height() - top, size.width(), top);
+	}, _unlock->lifetime());
+
+	_unlockHeight = _unlock->heightValue();
+
+	_unlock->paintRequest(
+	) | rpl::start_with_next([=] {
+		auto p = QPainter(_unlock);
+		const auto width = _unlock->width();
+		const auto fade = st::similarChannelsLockFade;
+		auto gradient = QLinearGradient(0, 0, 0, fade);
+		gradient.setStops({
+			{ 0., QColor(255, 255, 255, 0) },
+			{ 1., st::windowBg->c },
+		});
+		p.fillRect(0, 0, width, fade, gradient);
+		p.fillRect(0, fade, width, _unlock->height() - fade, st::windowBg);
+	}, _unlock->lifetime());
+}
+
+void ListController::loadMoreRows() {
+}
+
+std::unique_ptr<PeerListState> ListController::saveState() const {
+	auto result = PeerListController::saveState();
+	auto my = std::make_unique<SavedState>();
+	result->controllerState = std::move(my);
+	return result;
+}
+
+void ListController::restoreState(
+		std::unique_ptr<PeerListState> state) {
+	auto typeErasedState = state
+		? state->controllerState.get()
+		: nullptr;
+	if (auto my = dynamic_cast<SavedState*>(typeErasedState)) {
+		PeerListController::restoreState(std::move(state));
+	}
+}
+
+void ListController::rowClicked(not_null<PeerListRow*> row) {
+	_controller->parentController()->showPeerHistory(
+		row->peer(),
+		Window::SectionShow::Way::Forward);
+}
+
+} // namespace
+
+class InnerWidget final
+	: public Ui::RpWidget
+	, private PeerListContentDelegate {
+public:
+	InnerWidget(
+		QWidget *parent,
+		not_null<Controller*> controller,
+		not_null<ChannelData*> channel);
+
+	[[nodiscard]] not_null<ChannelData*> channel() const {
+		return _channel;
+	}
+
+	rpl::producer<Ui::ScrollToRequest> scrollToRequests() const;
+
+	int desiredHeight() const;
+
+	void saveState(not_null<Memento*> memento);
+	void restoreState(not_null<Memento*> memento);
+
+protected:
+	void visibleTopBottomUpdated(
+		int visibleTop,
+		int visibleBottom) override;
+
+private:
+	using ListWidget = PeerListContent;
+
+	// PeerListContentDelegate interface.
+	void peerListSetTitle(rpl::producer<QString> title) override;
+	void peerListSetAdditionalTitle(rpl::producer<QString> title) override;
+	bool peerListIsRowChecked(not_null<PeerListRow*> row) override;
+	int peerListSelectedRowsCount() override;
+	void peerListScrollToTop() override;
+	void peerListAddSelectedPeerInBunch(
+		not_null<PeerData*> peer) override;
+	void peerListAddSelectedRowInBunch(
+		not_null<PeerListRow*> row) override;
+	void peerListFinishSelectedRowsBunch() override;
+	void peerListSetDescription(
+		object_ptr<Ui::FlatLabel> description) override;
+	std::shared_ptr<Main::SessionShow> peerListUiShow() override;
+
+	object_ptr<ListWidget> setupList(
+		RpWidget *parent,
+		not_null<ListController*> controller);
+
+	const std::shared_ptr<Main::SessionShow> _show;
+	not_null<Controller*> _controller;
+	const not_null<ChannelData*> _channel;
+	std::unique_ptr<ListController> _listController;
+	object_ptr<ListWidget> _list;
+
+	rpl::event_stream<Ui::ScrollToRequest> _scrollToRequests;
+
+};
+
+InnerWidget::InnerWidget(
+	QWidget *parent,
+	not_null<Controller*> controller,
+	not_null<ChannelData*> channel)
+: RpWidget(parent)
+, _show(controller->uiShow())
+, _controller(controller)
+, _channel(channel)
+, _listController(std::make_unique<ListController>(controller, _channel))
+, _list(setupList(this, _listController.get())) {
+	setContent(_list.data());
+	_listController->setDelegate(static_cast<PeerListDelegate*>(this));
+}
+
+void InnerWidget::visibleTopBottomUpdated(
+		int visibleTop,
+		int visibleBottom) {
+	setChildVisibleTopBottom(_list, visibleTop, visibleBottom);
+}
+
+void InnerWidget::saveState(not_null<Memento*> memento) {
+	memento->setListState(_listController->saveState());
+}
+
+void InnerWidget::restoreState(not_null<Memento*> memento) {
+	_listController->restoreState(memento->listState());
+}
+
+rpl::producer<Ui::ScrollToRequest> InnerWidget::scrollToRequests() const {
+	return _scrollToRequests.events();
+}
+
+int InnerWidget::desiredHeight() const {
+	auto desired = 0;
+	desired += _list->fullRowsCount() * st::infoMembersList.item.height;
+	return qMax(height(), desired);
+}
+
+object_ptr<InnerWidget::ListWidget> InnerWidget::setupList(
+		RpWidget *parent,
+		not_null<ListController*> controller) {
+	controller->setStyleOverrides(&st::infoMembersList);
+	auto result = object_ptr<ListWidget>(
+		parent,
+		controller);
+	controller->setContentWidget(this);
+	result->scrollToRequests(
+	) | rpl::start_with_next([this](Ui::ScrollToRequest request) {
+		auto addmin = (request.ymin < 0)
+			? 0
+			: st::infoCommonGroupsMargin.top();
+		auto addmax = (request.ymax < 0)
+			? 0
+			: st::infoCommonGroupsMargin.top();
+		_scrollToRequests.fire({
+			request.ymin + addmin,
+			request.ymax + addmax });
+	}, result->lifetime());
+	result->moveToLeft(0, st::infoCommonGroupsMargin.top());
+	parent->widthValue(
+	) | rpl::start_with_next([list = result.data()](int newWidth) {
+		list->resizeToWidth(newWidth);
+	}, result->lifetime());
+	rpl::combine(
+		result->heightValue(),
+		controller->unlockHeightValue()
+	) | rpl::start_with_next([=](int listHeight, int unlockHeight) {
+		auto newHeight = st::infoCommonGroupsMargin.top()
+			+ listHeight
+			+ (unlockHeight
+				? (unlockHeight - st::similarChannelsLockOverlap)
+				: st::infoCommonGroupsMargin.bottom());
+		parent->resize(parent->width(), std::max(newHeight, 0));
+	}, result->lifetime());
+	return result;
+}
+
+void InnerWidget::peerListSetTitle(rpl::producer<QString> title) {
+}
+
+void InnerWidget::peerListSetAdditionalTitle(rpl::producer<QString> title) {
+}
+
+bool InnerWidget::peerListIsRowChecked(not_null<PeerListRow*> row) {
+	return false;
+}
+
+int InnerWidget::peerListSelectedRowsCount() {
+	return 0;
+}
+
+void InnerWidget::peerListScrollToTop() {
+	_scrollToRequests.fire({ -1, -1 });
+}
+
+void InnerWidget::peerListAddSelectedPeerInBunch(not_null<PeerData*> peer) {
+	Unexpected("Item selection in Info::Profile::Members.");
+}
+
+void InnerWidget::peerListAddSelectedRowInBunch(not_null<PeerListRow*> row) {
+	Unexpected("Item selection in Info::Profile::Members.");
+}
+
+void InnerWidget::peerListFinishSelectedRowsBunch() {
+}
+
+void InnerWidget::peerListSetDescription(
+		object_ptr<Ui::FlatLabel> description) {
+	description.destroy();
+}
+
+std::shared_ptr<Main::SessionShow> InnerWidget::peerListUiShow() {
+	return _show;
+}
+
+Memento::Memento(not_null<ChannelData*> channel)
+: ContentMemento(channel, nullptr, PeerId()) {
+}
+
+Section Memento::section() const {
+	return Section(Section::Type::SimilarChannels);
+}
+
+not_null<ChannelData*> Memento::channel() const {
+	return peer()->asChannel();
+}
+
+object_ptr<ContentWidget> Memento::createWidget(
+		QWidget *parent,
+		not_null<Controller*> controller,
+		const QRect &geometry) {
+	auto result = object_ptr<Widget>(parent, controller, channel());
+	result->setInternalState(geometry, this);
+	return result;
+}
+
+void Memento::setListState(std::unique_ptr<PeerListState> state) {
+	_listState = std::move(state);
+}
+
+std::unique_ptr<PeerListState> Memento::listState() {
+	return std::move(_listState);
+}
+
+Memento::~Memento() = default;
+
+Widget::Widget(
+	QWidget *parent,
+	not_null<Controller*> controller,
+	not_null<ChannelData*> channel)
+: ContentWidget(parent, controller) {
+	_inner = setInnerWidget(object_ptr<InnerWidget>(
+		this,
+		controller,
+		channel));
+}
+
+rpl::producer<QString> Widget::title() {
+	return tr::lng_similar_channels_title();
+}
+
+not_null<ChannelData*> Widget::channel() const {
+	return _inner->channel();
+}
+
+bool Widget::showInternal(not_null<ContentMemento*> memento) {
+	if (!controller()->validateMementoPeer(memento)) {
+		return false;
+	}
+	if (auto similarMemento = dynamic_cast<Memento*>(memento.get())) {
+		if (similarMemento->channel() == channel()) {
+			restoreState(similarMemento);
+			return true;
+		}
+	}
+	return false;
+}
+
+void Widget::setInternalState(
+		const QRect &geometry,
+		not_null<Memento*> memento) {
+	setGeometry(geometry);
+	Ui::SendPendingMoveResizeEvents(this);
+	restoreState(memento);
+}
+
+std::shared_ptr<ContentMemento> Widget::doCreateMemento() {
+	auto result = std::make_shared<Memento>(channel());
+	saveState(result.get());
+	return result;
+}
+
+void Widget::saveState(not_null<Memento*> memento) {
+	memento->setScrollTop(scrollTopSave());
+	_inner->saveState(memento);
+}
+
+void Widget::restoreState(not_null<Memento*> memento) {
+	_inner->restoreState(memento);
+	scrollTopRestore(memento->scrollTop());
+}
+
+} // namespace Info::SimilarChannels
+

Telegram/SourceFiles/info/similar_channels/info_similar_channels_widget.h

@@ -0,0 +1,71 @@
+/*
+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 "info/info_content_widget.h"
+
+class ChannelData;
+struct PeerListState;
+
+namespace Info::SimilarChannels {
+
+class InnerWidget;
+
+class Memento final : public ContentMemento {
+public:
+	explicit Memento(not_null<ChannelData*> channel);
+
+	object_ptr<ContentWidget> createWidget(
+		QWidget *parent,
+		not_null<Controller*> controller,
+		const QRect &geometry) override;
+
+	Section section() const override;
+
+	[[nodiscard]] not_null<ChannelData*> channel() const;
+
+	void setListState(std::unique_ptr<PeerListState> state);
+	std::unique_ptr<PeerListState> listState();
+
+	~Memento();
+
+private:
+	std::unique_ptr<PeerListState> _listState;
+
+};
+
+class Widget final : public ContentWidget {
+public:
+	Widget(
+		QWidget *parent,
+		not_null<Controller*> controller,
+		not_null<ChannelData*> channel);
+
+	[[nodiscard]] not_null<ChannelData*> channel() const;
+
+	bool showInternal(
+		not_null<ContentMemento*> memento) override;
+
+	void setInternalState(
+		const QRect &geometry,
+		not_null<Memento*> memento);
+
+	rpl::producer<QString> title() override;
+
+private:
+	void saveState(not_null<Memento*> memento);
+	void restoreState(not_null<Memento*> memento);
+
+	std::shared_ptr<ContentMemento> doCreateMemento() override;
+
+	InnerWidget *_inner = nullptr;
+
+};
+
+} // namespace Info::SimilarChannels
+

Telegram/SourceFiles/window/window_session_controller.h

@@ -160,6 +160,7 @@ struct SectionShow {
 	anim::activation activation = anim::activation::normal;
 	bool thirdColumn = false;
 	bool childColumn = false;
+	bool forbidLayer = false;
 	bool reapplyLocalDraft = false;
 	Origin origin;
 

Telegram/lib_ui

@@ -1 +1 @@
-Subproject commit 66ca90c1b2c111fe8ae45453c7bf180af2593d8d
+Subproject commit 44161f183c255dc0dac7ebe9558a1ca48f5e5258