From 5fb71cb165089181af266e9dc34fec14b7674cb8 Mon Sep 17 00:00:00 2001
From: 23rd <23rd@vivaldi.net>
Date: Tue, 3 May 2022 18:43:04 +0300
Subject: [PATCH] Added ability to append pinned to bottom content to settings
 sections.

---
 .../SourceFiles/info/info_content_widget.cpp  | 23 +++++++++++++------
 .../SourceFiles/info/info_content_widget.h    |  2 ++
 .../info/settings/info_settings_widget.cpp    | 23 ++++++++++++++++++-
 .../info/settings/info_settings_widget.h      |  1 +
 .../SourceFiles/settings/settings_common.h    |  4 ++++
 5 files changed, 45 insertions(+), 8 deletions(-)

diff --git a/Telegram/SourceFiles/info/info_content_widget.cpp b/Telegram/SourceFiles/info/info_content_widget.cpp
index bec308988..eadc09e7c 100644
--- a/Telegram/SourceFiles/info/info_content_widget.cpp
+++ b/Telegram/SourceFiles/info/info_content_widget.cpp
@@ -61,7 +61,9 @@ ContentWidget::ContentWidget(
 			refreshSearchField(shown);
 		}, lifetime());
 	}
-	_scrollTopSkip.changes(
+	rpl::merge(
+		_scrollTopSkip.changes(),
+		_scrollBottomSkip.changes()
 	) | rpl::start_with_next([this] {
 		updateControlsGeometry();
 	}, lifetime());
@@ -79,7 +81,7 @@ void ContentWidget::updateControlsGeometry() {
 
 	auto newScrollTop = _scroll->scrollTop() + _topDelta;
 	auto scrollGeometry = rect().marginsRemoved(
-		QMargins(0, _scrollTopSkip.current(), 0, 0));
+		{ 0, _scrollTopSkip.current(), 0, _scrollBottomSkip.current() });
 	if (_scroll->geometry() != scrollGeometry) {
 		_scroll->setGeometry(scrollGeometry);
 	}
@@ -159,9 +161,11 @@ Ui::RpWidget *ContentWidget::doSetInnerWidget(
 }
 
 int ContentWidget::scrollTillBottom(int forHeight) const {
-	auto scrollHeight = forHeight - _scrollTopSkip.current();
-	auto scrollBottom = _scroll->scrollTop() + scrollHeight;
-	auto desired = _innerDesiredHeight;
+	const auto scrollHeight = forHeight
+		- _scrollTopSkip.current()
+		- _scrollBottomSkip.current();
+	const auto scrollBottom = _scroll->scrollTop() + scrollHeight;
+	const auto desired = _innerDesiredHeight;
 	return std::max(desired - scrollBottom, 0);
 }
 
@@ -173,6 +177,10 @@ void ContentWidget::setScrollTopSkip(int scrollTopSkip) {
 	_scrollTopSkip = scrollTopSkip;
 }
 
+void ContentWidget::setScrollBottomSkip(int scrollBottomSkip) {
+	_scrollBottomSkip = scrollBottomSkip;
+}
+
 rpl::producer<int> ContentWidget::scrollHeightValue() const {
 	return _scroll->heightValue();
 }
@@ -187,8 +195,9 @@ rpl::producer<int> ContentWidget::desiredHeightValue() const {
 	using namespace rpl::mappers;
 	return rpl::combine(
 		_innerWrap->entity()->desiredHeightValue(),
-		_scrollTopSkip.value()
-	) | rpl::map(_1 + _2);
+		_scrollTopSkip.value(),
+		_scrollBottomSkip.value()
+	) | rpl::map(_1 + _2 + _3);
 }
 
 rpl::producer<bool> ContentWidget::desiredShadowVisibility() const {
diff --git a/Telegram/SourceFiles/info/info_content_widget.h b/Telegram/SourceFiles/info/info_content_widget.h
index 3cc5b34a5..be548fbf1 100644
--- a/Telegram/SourceFiles/info/info_content_widget.h
+++ b/Telegram/SourceFiles/info/info_content_widget.h
@@ -94,6 +94,7 @@ protected:
 	void paintEvent(QPaintEvent *e) override;
 
 	void setScrollTopSkip(int scrollTopSkip);
+	void setScrollBottomSkip(int scrollBottomSkip);
 	int scrollTopSave() const;
 	void scrollTopRestore(int scrollTop);
 	void scrollTo(const Ui::ScrollToRequest &request);
@@ -109,6 +110,7 @@ private:
 
 	style::color _bg;
 	rpl::variable<int> _scrollTopSkip = -1;
+	rpl::variable<int> _scrollBottomSkip = -1;
 	rpl::event_stream<int> _scrollTillBottomChanges;
 	object_ptr<Ui::ScrollArea> _scroll;
 	Ui::PaddingWrap<Ui::RpWidget> *_innerWrap = nullptr;
diff --git a/Telegram/SourceFiles/info/settings/info_settings_widget.cpp b/Telegram/SourceFiles/info/settings/info_settings_widget.cpp
index d20d5490f..285497ed6 100644
--- a/Telegram/SourceFiles/info/settings/info_settings_widget.cpp
+++ b/Telegram/SourceFiles/info/settings/info_settings_widget.cpp
@@ -48,7 +48,8 @@ Widget::Widget(
 , _inner(
 	setInnerWidget(
 		_type()->create(this, controller->parentController())))
-, _pinnedToTop(_inner->createPinnedToTop(this)) {
+, _pinnedToTop(_inner->createPinnedToTop(this))
+, _pinnedToBottom(_inner->createPinnedToBottom(this)) {
 	_inner->sectionShowOther(
 	) | rpl::start_with_next([=](Type type) {
 		controller->showSettings(type);
@@ -81,6 +82,26 @@ Widget::Widget(
 			setScrollTopSkip(h);
 		}, _pinnedToTop->lifetime());
 	}
+
+	if (_pinnedToBottom) {
+		const auto processHeight = [=](int bottomHeight, int height) {
+			setScrollBottomSkip(bottomHeight);
+			_pinnedToBottom->moveToLeft(
+				_pinnedToBottom->x(),
+				height - bottomHeight);
+		};
+
+		_inner->sizeValue(
+		) | rpl::start_with_next([=](const QSize &s) {
+			_pinnedToBottom->resizeToWidth(s.width());
+			processHeight(_pinnedToBottom->height(), height());
+		}, _pinnedToBottom->lifetime());
+
+		rpl::combine(
+			_pinnedToBottom->heightValue(),
+			heightValue()
+		) | rpl::start_with_next(processHeight, _pinnedToBottom->lifetime());
+	}
 }
 
 Widget::~Widget() = default;
diff --git a/Telegram/SourceFiles/info/settings/info_settings_widget.h b/Telegram/SourceFiles/info/settings/info_settings_widget.h
index d6de4287d..5b6290ba8 100644
--- a/Telegram/SourceFiles/info/settings/info_settings_widget.h
+++ b/Telegram/SourceFiles/info/settings/info_settings_widget.h
@@ -83,6 +83,7 @@ private:
 
 	not_null<::Settings::AbstractSection*> _inner;
 	QPointer<Ui::RpWidget> _pinnedToTop;
+	QPointer<Ui::RpWidget> _pinnedToBottom;
 
 	rpl::event_stream<std::vector<Type>> _removesFromStack;
 
diff --git a/Telegram/SourceFiles/settings/settings_common.h b/Telegram/SourceFiles/settings/settings_common.h
index 03566fdfb..adf4e62fd 100644
--- a/Telegram/SourceFiles/settings/settings_common.h
+++ b/Telegram/SourceFiles/settings/settings_common.h
@@ -96,6 +96,10 @@ public:
 			not_null<QWidget*> parent) {
 		return nullptr;
 	}
+	[[nodiscard]] virtual QPointer<Ui::RpWidget> createPinnedToBottom(
+			not_null<Ui::RpWidget*> parent) {
+		return nullptr;
+	}
 };
 
 template <typename SectionType>