Load and show image previews in pinned bar.

Telegram/SourceFiles/data/data_document.cpp

@@ -1266,6 +1266,15 @@ Image *DocumentData::getReplyPreview(Data::FileOrigin origin) {
 	return _replyPreview->image(origin);
 }
 
+bool DocumentData::replyPreviewLoaded() const {
+	if (!hasThumbnail()) {
+		return true;
+	} else if (!_replyPreview) {
+		return false;
+	}
+	return _replyPreview->loaded();
+}
+
 StickerData *DocumentData::sticker() const {
 	return (type == StickerDocument)
 		? static_cast<StickerData*>(_additional.get())

Telegram/SourceFiles/data/data_document.h

@@ -126,6 +126,7 @@ public:
 	[[nodiscard]] bool saveToCache() const;
 
 	[[nodiscard]] Image *getReplyPreview(Data::FileOrigin origin);
+	[[nodiscard]] bool replyPreviewLoaded() const;
 
 	[[nodiscard]] StickerData *sticker() const;
 	[[nodiscard]] Data::FileOrigin stickerSetOrigin() const;

Telegram/SourceFiles/data/data_media_types.cpp

@@ -209,6 +209,10 @@ Image *Media::replyPreview() const {
 	return nullptr;
 }
 
+bool Media::replyPreviewLoaded() const {
+	return true;
+}
+
 bool Media::allowsForward() const {
 	return true;
 }
@@ -312,6 +316,10 @@ Image *MediaPhoto::replyPreview() const {
 	return _photo->getReplyPreview(parent()->fullId());
 }
 
+bool MediaPhoto::replyPreviewLoaded() const {
+	return _photo->replyPreviewLoaded();
+}
+
 QString MediaPhoto::notificationText() const {
 	return WithCaptionNotificationText(
 		tr::lng_in_dlg_photo(tr::now),
@@ -476,6 +484,10 @@ Image *MediaFile::replyPreview() const {
 	return _document->getReplyPreview(parent()->fullId());
 }
 
+bool MediaFile::replyPreviewLoaded() const {
+	return _document->replyPreviewLoaded();
+}
+
 QString MediaFile::chatListText() const {
 	if (const auto sticker = _document->sticker()) {
 		return Media::chatListText();
@@ -987,6 +999,15 @@ Image *MediaWebPage::replyPreview() const {
 	return nullptr;
 }
 
+bool MediaWebPage::replyPreviewLoaded() const {
+	if (const auto document = MediaWebPage::document()) {
+		return document->replyPreviewLoaded();
+	} else if (const auto photo = MediaWebPage::photo()) {
+		return photo->replyPreviewLoaded();
+	}
+	return true;
+}
+
 QString MediaWebPage::chatListText() const {
 	return notificationText();
 }
@@ -1051,6 +1072,15 @@ Image *MediaGame::replyPreview() const {
 	return nullptr;
 }
 
+bool MediaGame::replyPreviewLoaded() const {
+	if (const auto document = _game->document) {
+		return document->replyPreviewLoaded();
+	} else if (const auto photo = _game->photo) {
+		return photo->replyPreviewLoaded();
+	}
+	return true;
+}
+
 QString MediaGame::notificationText() const {
 	// Add a game controller emoji before game title.
 	auto result = QString();
@@ -1153,6 +1183,13 @@ Image *MediaInvoice::replyPreview() const {
 	return nullptr;
 }
 
+bool MediaInvoice::replyPreviewLoaded() const {
+	if (const auto photo = _invoice.photo) {
+		return photo->replyPreviewLoaded();
+	}
+	return true;
+}
+
 QString MediaInvoice::notificationText() const {
 	return _invoice.title;
 }

Telegram/SourceFiles/data/data_media_types.h

@@ -88,6 +88,7 @@ public:
 	virtual bool canBeGrouped() const;
 	virtual bool hasReplyPreview() const;
 	virtual Image *replyPreview() const;
+	virtual bool replyPreviewLoaded() const;
 	// Returns text with link-start and link-end commands for service-color highlighting.
 	// Example: "[link1-start]You:[link1-end] [link1-start]Photo,[link1-end] caption text"
 	virtual QString chatListText() const;
@@ -143,6 +144,7 @@ public:
 	bool canBeGrouped() const override;
 	bool hasReplyPreview() const override;
 	Image *replyPreview() const override;
+	bool replyPreviewLoaded() const override;
 	QString chatListText() const override;
 	QString notificationText() const override;
 	QString pinnedTextSubstring() const override;
@@ -180,6 +182,7 @@ public:
 	bool canBeGrouped() const override;
 	bool hasReplyPreview() const override;
 	Image *replyPreview() const override;
+	bool replyPreviewLoaded() const override;
 	QString chatListText() const override;
 	QString notificationText() const override;
 	QString pinnedTextSubstring() const override;
@@ -311,6 +314,7 @@ public:
 
 	bool hasReplyPreview() const override;
 	Image *replyPreview() const override;
+	bool replyPreviewLoaded() const override;
 	QString chatListText() const override;
 	QString notificationText() const override;
 	QString pinnedTextSubstring() const override;
@@ -341,6 +345,7 @@ public:
 
 	bool hasReplyPreview() const override;
 	Image *replyPreview() const override;
+	bool replyPreviewLoaded() const override;
 	QString notificationText() const override;
 	QString pinnedTextSubstring() const override;
 	TextForMimeData clipboardText() const override;
@@ -377,6 +382,7 @@ public:
 
 	bool hasReplyPreview() const override;
 	Image *replyPreview() const override;
+	bool replyPreviewLoaded() const override;
 	QString notificationText() const override;
 	QString pinnedTextSubstring() const override;
 	TextForMimeData clipboardText() const override;

Telegram/SourceFiles/data/data_photo.cpp

@@ -205,6 +205,13 @@ Image *PhotoData::getReplyPreview(Data::FileOrigin origin) {
 	return _replyPreview->image(origin);
 }
 
+bool PhotoData::replyPreviewLoaded() const {
+	if (!_replyPreview) {
+		return false;
+	}
+	return _replyPreview->loaded();
+}
+
 void PhotoData::setRemoteLocation(
 		int32 dc,
 		uint64 access,

Telegram/SourceFiles/data/data_photo.h

@@ -65,6 +65,7 @@ public:
 	[[nodiscard]] bool waitingForAlbum() const;
 
 	[[nodiscard]] Image *getReplyPreview(Data::FileOrigin origin);
+	[[nodiscard]] bool replyPreviewLoaded() const;
 
 	void setRemoteLocation(
 		int32 dc,

Telegram/SourceFiles/data/data_reply_preview.cpp

@@ -107,4 +107,8 @@ Image *ReplyPreview::image(Data::FileOrigin origin) {
 	return _image.get();
 }
 
+bool ReplyPreview::loaded() const {
+	return _checked;
+}
+
 } // namespace Data

Telegram/SourceFiles/data/data_reply_preview.h

@@ -24,6 +24,7 @@ public:
 	~ReplyPreview();
 
 	[[nodiscard]] Image *image(Data::FileOrigin origin);
+	[[nodiscard]] bool loaded() const;
 
 private:
 	void prepare(not_null<Image*> image, Images::Options options);

Telegram/SourceFiles/history/view/history_view_pinned_bar.cpp

@@ -23,29 +23,84 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 namespace HistoryView {
 namespace {
 
+[[nodiscard]] Ui::MessageBarContent ContentWithoutPreview(
+		not_null<HistoryItem*> item,
+		PinnedIdType type) {
+	const auto media = item->media();
+	const auto poll = media ? media->poll() : nullptr;
+	return Ui::MessageBarContent{
+		.id = item->id,
+		.title = ((type == PinnedIdType::First)
+			? tr::lng_pinned_previous(tr::now) // #TODO pinned first?
+			: (type == PinnedIdType::Middle)
+			? tr::lng_pinned_previous(tr::now)
+			: !poll
+			? tr::lng_pinned_message(tr::now)
+			: poll->quiz()
+			? tr::lng_pinned_quiz(tr::now)
+			: tr::lng_pinned_poll(tr::now)),
+		.text = item->inReplyText(),
+	};
+}
+
+[[nodiscard]] Ui::MessageBarContent ContentWithPreview(
+		not_null<HistoryItem*> item,
+		PinnedIdType type,
+		Image *preview) {
+	auto result = ContentWithoutPreview(item, type);
+	if (!preview) {
+		static const auto kEmpty = [&] {
+			const auto size = st::historyReplyHeight * cIntRetinaFactor();
+			auto result = QImage(
+				QSize(size, size),
+				QImage::Format_ARGB32_Premultiplied);
+			result.fill(Qt::transparent);
+			result.setDevicePixelRatio(cRetinaFactor());
+			return result;
+		}();
+		result.preview = kEmpty;
+	} else {
+		result.preview = preview->original();
+	}
+	return result;
+}
+
 [[nodiscard]] rpl::producer<Ui::MessageBarContent> ContentByItem(
 		not_null<HistoryItem*> item,
 		PinnedIdType type) {
 	return item->history()->session().changes().messageFlagsValue(
 		item,
 		Data::MessageUpdate::Flag::Edited
-	) | rpl::map([=] {
+	) | rpl::map([=]() -> rpl::producer<Ui::MessageBarContent> {
 		const auto media = item->media();
-		const auto poll = media ? media->poll() : nullptr;
-		return Ui::MessageBarContent{
-			.id = item->id,
-			.title = ((type == PinnedIdType::First)
-				? tr::lng_pinned_previous(tr::now) // #TODO pinned first?
-				: (type == PinnedIdType::Middle)
-				? tr::lng_pinned_previous(tr::now)
-				: !poll
-				? tr::lng_pinned_message(tr::now)
-				: poll->quiz()
-				? tr::lng_pinned_quiz(tr::now)
-				: tr::lng_pinned_poll(tr::now)),
-			.text = item->inReplyText(),
+		if (!media || !media->hasReplyPreview()) {
+			return rpl::single(ContentWithoutPreview(item, type));
+		}
+		constexpr auto kFullLoaded = 2;
+		constexpr auto kSomeLoaded = 1;
+		constexpr auto kNotLoaded = 0;
+		const auto loadedLevel = [=] {
+			const auto preview = media->replyPreview();
+			return media->replyPreviewLoaded()
+				? kFullLoaded
+				: preview
+				? kSomeLoaded
+				: kNotLoaded;
 		};
-	});
+		return rpl::single(
+			loadedLevel()
+		) | rpl::then(
+			item->history()->session().downloaderTaskFinished(
+			) | rpl::map(loadedLevel)
+		) | rpl::distinct_until_changed(
+		) | rpl::take_while([=](int loadLevel) {
+			return loadLevel < kFullLoaded;
+		}) | rpl::then(
+			rpl::single(kFullLoaded)
+		) | rpl::map([=] {
+			return ContentWithPreview(item, type, media->replyPreview());
+		});
+	}) | rpl::flatten_latest();
 }
 
 [[nodiscard]] rpl::producer<Ui::MessageBarContent> ContentByItemId(