Update current theme in realtime.

Telegram/SourceFiles/data/data_cloud_themes.cpp

@@ -7,12 +7,21 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #include "data/data_cloud_themes.h"
 
+#include "window/themes/window_theme.h"
+#include "window/themes/window_theme_preview.h"
 #include "data/data_session.h"
 #include "data/data_document.h"
+#include "data/data_file_origin.h"
 #include "main/main_session.h"
 #include "apiwrap.h"
 
 namespace Data {
+namespace {
+
+constexpr auto kFirstReloadTimeout = 60 * crl::time(1000);
+constexpr auto kReloadTimeout = 3600 * crl::time(1000);
+
+} // namespace
 
 CloudTheme CloudTheme::Parse(
 		not_null<Main::Session*> session,
@@ -36,7 +45,103 @@ QString CloudThemes::Format() {
 }
 
 CloudThemes::CloudThemes(not_null<Main::Session*> session)
-: _session(session) {
+: _session(session)
+, _reloadCurrentTimer([=] { reloadCurrent(); }) {
+	setupReload();
+}
+
+void CloudThemes::setupReload() {
+	using namespace Window::Theme;
+
+	if (needReload()) {
+		_reloadCurrentTimer.callOnce(kFirstReloadTimeout);
+	}
+	base::ObservableViewer(
+		*Background()
+	) | rpl::filter([](const BackgroundUpdate &update) {
+		return (update.type == BackgroundUpdate::Type::ApplyingTheme);
+	}) | rpl::map([=] {
+		return needReload();
+	}) | rpl::start_with_next([=](bool need) {
+		if (need) {
+			scheduleReload();
+		} else {
+			_reloadCurrentTimer.cancel();
+		}
+	}, _lifetime);
+}
+
+bool CloudThemes::needReload() const {
+	const auto &fields = Window::Theme::Background()->themeObject().cloud;
+	return fields.id && fields.documentId;
+}
+
+void CloudThemes::reloadCurrent() {
+	if (!needReload()) {
+		return;
+	}
+	const auto &fields = Window::Theme::Background()->themeObject().cloud;
+	_session->api().request(MTPaccount_GetTheme(
+		MTP_string(Format()),
+		MTP_inputTheme(MTP_long(fields.id), MTP_long(fields.accessHash)),
+		MTP_long(fields.documentId)
+	)).done([=](const MTPTheme &result) {
+		applyUpdate(result);
+	}).fail([=](const RPCError &error) {
+		_reloadCurrentTimer.callOnce(kReloadTimeout);
+	}).send();
+}
+
+void CloudThemes::applyUpdate(const MTPTheme &theme) {
+	theme.match([&](const MTPDtheme &data) {
+		const auto cloud = CloudTheme::Parse(_session, data);
+		const auto &object = Window::Theme::Background()->themeObject();
+		if ((cloud.id != object.cloud.id)
+			|| (cloud.documentId == object.cloud.documentId)) {
+			return;
+		}
+		if (const auto updated = data.vdocument()) {
+			updateFromDocument(
+				cloud,
+				_session->data().processDocument(*updated));
+		}
+	}, [&](const MTPDthemeDocumentNotModified &data) {
+	});
+	scheduleReload();
+}
+
+void CloudThemes::updateFromDocument(
+		const CloudTheme &cloud,
+		not_null<DocumentData*> document) {
+	if (_updatingFrom) {
+		_updatingFrom->cancel();
+	} else {
+		base::ObservableViewer(
+			_session->downloaderTaskFinished()
+		) | rpl::filter([=] {
+			return _updatingFrom->loaded();
+		}) | rpl::start_with_next([=] {
+			_updatingFromLifetime.destroy();
+			auto preview = Window::Theme::PreviewFromFile(
+				document->data(),
+				document->location().name(),
+				cloud);
+			if (preview) {
+				Window::Theme::Apply(std::move(preview));
+			}
+		}, _updatingFromLifetime);
+	}
+
+	_updatingFrom = document;
+	_updatingFrom->save(Data::FileOrigin(), QString()); // #TODO themes
+}
+
+void CloudThemes::scheduleReload() {
+	if (needReload()) {
+		_reloadCurrentTimer.callOnce(kReloadTimeout);
+	} else {
+		_reloadCurrentTimer.cancel();
+	}
 }
 
 void CloudThemes::refresh() {

Telegram/SourceFiles/data/data_cloud_themes.h

@@ -7,6 +7,10 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #pragma once
 
+#include "base/timer.h"
+
+class DocumentData;
+
 namespace Main {
 class Session;
 } // namespace Main
@@ -37,15 +41,31 @@ public:
 	[[nodiscard]] const std::vector<CloudTheme> &list() const;
 	void apply(const CloudTheme &data);
 
+	void applyUpdate(const MTPTheme &theme);
+
 private:
 	void parseThemes(const QVector<MTPTheme> &list);
 
+	void setupReload();
+	[[nodiscard]] bool needReload() const;
+	void scheduleReload();
+	void reloadCurrent();
+	void updateFromDocument(
+		const CloudTheme &cloud,
+		not_null<DocumentData*> document);
+
 	const not_null<Main::Session*> _session;
 	int32 _hash = 0;
 	mtpRequestId _requestId = 0;
 	std::vector<CloudTheme> _list;
 	rpl::event_stream<> _updates;
 
+	base::Timer _reloadCurrentTimer;
+	DocumentData *_updatingFrom = nullptr;
+	rpl::lifetime _updatingFromLifetime;
+
+	rpl::lifetime _lifetime;
+
 };
 
 } // namespace Data

Telegram/SourceFiles/mainwidget.cpp

@@ -4612,5 +4612,11 @@ void MainWidget::feedUpdate(const MTPUpdate &update) {
 		}
 	} break;
 
+	////// Cloud themes
+	case mtpc_updateTheme: {
+		const auto &data = update.c_updateTheme();
+		session().data().cloudThemes().applyUpdate(data.vtheme());
+	} break;
+
 	}
 }