Remove flags checking for backgrounds.

Also limit image size to 2960px.

Fixes #5641.

Telegram/SourceFiles/boxes/background_box.cpp

@@ -573,8 +573,7 @@ void BackgroundPreviewBox::checkLoadedDocument() {
 		|| _generating) {
 		return;
 	}
-	_generating = Data::ReadImageAsync(document, [=](
-			QImage &&image) mutable {
+	const auto generateCallback = [=](QImage &&image) {
 		auto [left, right] = base::make_binary_guard();
 		_generating = std::move(left);
 		crl::async([
@@ -598,7 +597,11 @@ void BackgroundPreviewBox::checkLoadedDocument() {
 				update();
 			});
 		});
-	});
+	};
+	_generating = Data::ReadImageAsync(
+		document,
+		Window::Theme::ProcessBackgroundImage,
+		generateCallback);
 }
 
 bool BackgroundPreviewBox::Start(

Telegram/SourceFiles/data/data_document.cpp

@@ -1597,11 +1597,13 @@ vst vstm vstx vsw vsx vtx website ws wsc wsf wsh xbap xll xnk");
 
 base::binary_guard ReadImageAsync(
 		not_null<DocumentData*> document,
+		FnMut<QImage(QImage)> postprocess,
 		FnMut<void(QImage&&)> done) {
 	auto [left, right] = base::make_binary_guard();
 	crl::async([
 		bytes = document->data(),
 		path = document->filepath(),
+		postprocess = std::move(postprocess),
 		guard = std::move(left),
 		callback = std::move(done)
 	]() mutable {
@@ -1616,6 +1618,9 @@ base::binary_guard ReadImageAsync(
 		auto image = bytes.isEmpty()
 			? QImage()
 			: App::readImage(bytes, &format, false, nullptr);
+		if (postprocess) {
+			image = postprocess(std::move(image));
+		}
 		crl::on_main([
 			guard = std::move(guard),
 			image = std::move(image),

Telegram/SourceFiles/data/data_document.h

@@ -378,6 +378,7 @@ bool IsValidMediaFile(const QString &filepath);
 bool IsExecutableName(const QString &filepath);
 base::binary_guard ReadImageAsync(
 	not_null<DocumentData*> document,
+	FnMut<QImage(QImage)> postprocess,
 	FnMut<void(QImage&&)> done);
 
 } // namespace Data

Telegram/SourceFiles/mainwidget.cpp

@@ -1629,14 +1629,17 @@ void MainWidget::checkChatBackground() {
 		return;
 	}
 
-	_background->generating = Data::ReadImageAsync(document, [=](
-			QImage &&image) {
+	const auto generateCallback = [=](QImage &&image) {
 		const auto background = base::take(_background);
 		const auto ready = image.isNull()
 			? Data::DefaultWallPaper()
 			: background->data;
 		setReadyChatBackground(ready, std::move(image));
-	});
+	};
+	_background->generating = Data::ReadImageAsync(
+		document,
+		Window::Theme::ProcessBackgroundImage,
+		generateCallback);
 }
 
 Image *MainWidget::newBackgroundThumb() {

Telegram/SourceFiles/window/themes/window_theme.cpp

@@ -38,26 +38,6 @@ constexpr auto kCustomBackground = FromLegacyBackgroundId(-1);
 constexpr auto kLegacy1DefaultBackground = FromLegacyBackgroundId(0);
 constexpr auto kDefaultBackground = FromLegacyBackgroundId(105);
 
-[[nodiscard]] bool ValidateFlags(MTPDwallPaper::Flags flags) {
-	using Flag = MTPDwallPaper::Flag;
-	const auto all = Flag(0)
-		| Flag::f_creator
-		| Flag::f_default
-		| Flag::f_pattern
-		| Flag::f_settings;
-	return !(flags & ~all);
-}
-
-[[nodiscard]] bool ValidateFlags(MTPDwallPaperSettings::Flags flags) {
-	using Flag = MTPDwallPaperSettings::Flag;
-	const auto all = Flag(0)
-		| Flag::f_background_color
-		| Flag::f_blur
-		| Flag::f_intensity
-		| Flag::f_motion;
-	return !(flags & ~all);
-}
-
 quint32 SerializeMaybeColor(std::optional<QColor> color) {
 	return color
 		? ((quint32(std::clamp(color->red(), 0, 255)) << 16)
@@ -351,9 +331,6 @@ std::optional<WallPaper> WallPaper::FromSerialized(
 	result._settings = MTPDwallPaperSettings::Flags::from_raw(settings);
 	result._backgroundColor = MaybeColorFromSerialized(backgroundColor);
 	result._intensity = intensity;
-	if (!ValidateFlags(result._flags) || !ValidateFlags(result._settings)) {
-		return std::nullopt;
-	}
 	return result;
 }
 
@@ -367,9 +344,6 @@ std::optional<WallPaper> WallPaper::FromLegacySerialized(
 	result._flags = MTPDwallPaper::Flags::from_raw(flags);
 	result._slug = slug;
 	result._backgroundColor = ColorFromString(slug);
-	if (!ValidateFlags(result._flags)) {
-		return std::nullopt;
-	}
 	return result;
 }
 
@@ -897,10 +871,7 @@ void ChatBackground::start() {
 }
 
 void ChatBackground::set(const Data::WallPaper &paper, QImage image) {
-	if (image.format() != QImage::Format_ARGB32_Premultiplied) {
-		image = std::move(image).convertToFormat(
-			QImage::Format_ARGB32_Premultiplied);
-	}
+	image = ProcessBackgroundImage(std::move(image));
 
 	const auto needResetAdjustable = Data::IsDefaultWallPaper(paper)
 		&& !Data::IsDefaultWallPaper(_paper)
@@ -1578,6 +1549,32 @@ QColor AdjustedColor(QColor original, QColor background) {
 	).toRgb();
 }
 
+QImage ProcessBackgroundImage(QImage image) {
+	constexpr auto kMaxSize = 2960;
+
+	if (image.format() != QImage::Format_ARGB32_Premultiplied) {
+		image = std::move(image).convertToFormat(
+			QImage::Format_ARGB32_Premultiplied);
+	}
+	if (image.width() > 40 * image.height()) {
+		const auto width = 40 * image.height();
+		const auto height = image.height();
+		image = image.copy((image.width() - width) / 2, 0, width, height);
+	} else if (image.height() > 40 * image.width()) {
+		const auto width = image.width();
+		const auto height = 40 * image.width();
+		image = image.copy(0, (image.height() - height) / 2, width, height);
+	}
+	if (image.width() > kMaxSize || image.height() > kMaxSize) {
+		image = image.scaled(
+			kMaxSize,
+			kMaxSize,
+			Qt::KeepAspectRatio,
+			Qt::SmoothTransformation);
+	}
+	return image;
+}
+
 void ComputeBackgroundRects(QRect wholeFill, QSize imageSize, QRect &to, QRect &from) {
 	if (uint64(imageSize.width()) * wholeFill.height() > uint64(imageSize.height()) * wholeFill.width()) {
 		float64 pxsize = wholeFill.height() / float64(imageSize.height());

Telegram/SourceFiles/window/themes/window_theme.h

@@ -155,6 +155,7 @@ bool LoadFromFile(const QString &file, Instance *out, QByteArray *outContent);
 bool IsPaletteTestingPath(const QString &path);
 QColor CountAverageColor(const QImage &image);
 QColor AdjustedColor(QColor original, QColor background);
+QImage ProcessBackgroundImage(QImage image);
 
 struct BackgroundUpdate {
 	enum class Type {