Add Qt 6 support

Tested only on Linux so far

Telegram/CMakeLists.txt

@@ -1197,7 +1197,7 @@ else()
     )
 endif()
 
-if (DESKTOP_APP_DISABLE_WAYLAND_INTEGRATION)
+if (DESKTOP_APP_DISABLE_WAYLAND_INTEGRATION OR DESKTOP_APP_QT6)
     remove_target_sources(Telegram ${src_loc}
         platform/linux/linux_wayland_integration.cpp
     )
@@ -1289,10 +1289,16 @@ elseif (APPLE)
     endif()
 else()
     if (NOT DESKTOP_APP_DISABLE_DBUS_INTEGRATION)
+        if (NOT DESKTOP_APP_QT6)
+            target_link_libraries(Telegram
+            PRIVATE
+                desktop-app::external_statusnotifieritem
+                desktop-app::external_dbusmenu_qt
+            )
+        endif()
+
         target_link_libraries(Telegram
         PRIVATE
-            desktop-app::external_statusnotifieritem
-            desktop-app::external_dbusmenu_qt
             desktop-app::external_glibmm
             desktop-app::external_glib
         )
@@ -1309,8 +1315,14 @@ else()
         target_link_libraries(Telegram
         PRIVATE
             desktop-app::lib_waylandshells
-            desktop-app::external_kwayland
         )
+
+        if (NOT DESKTOP_APP_QT6)
+            target_link_libraries(Telegram
+            PRIVATE
+                desktop-app::external_kwayland
+            )
+        endif()
     endif()
 endif()
 

Telegram/SourceFiles/api/api_blocked_peers.cpp

@@ -26,7 +26,7 @@ BlockedPeers::Slice TLToSlice(
 		Data::Session &owner) {
 	const auto create = [&](int count, const QVector<MTPPeerBlocked> &list) {
 		auto slice = BlockedPeers::Slice();
-		slice.total = std::max(count, list.size());
+		slice.total = std::max(count, int(list.size()));
 		slice.list.reserve(list.size());
 		for (const auto &contact : list) {
 			contact.match([&](const MTPDpeerBlocked &data) {

Telegram/SourceFiles/api/api_sending.cpp

@@ -212,7 +212,7 @@ void SendExistingPhoto(
 }
 
 bool SendDice(Api::MessageToSend &message) {
-	const auto full = message.textWithTags.text.midRef(0).trimmed();
+	const auto full = QStringView(message.textWithTags.text).trimmed();
 	auto length = 0;
 	if (!Ui::Emoji::Find(full.data(), full.data() + full.size(), &length)
 		|| length != full.size()) {

Telegram/SourceFiles/api/api_who_read.cpp

@@ -159,7 +159,7 @@ struct State {
 				auto &entry = context->cache(item);
 				entry.requestId = 0;
 				auto peers = std::vector<PeerId>();
-				peers.reserve(std::max(result.v.size(), 1));
+				peers.reserve(std::max(int(result.v.size()), 1));
 				for (const auto &id : result.v) {
 					peers.push_back(UserId(id));
 				}

Telegram/SourceFiles/apiwrap.cpp

@@ -478,7 +478,7 @@ void ApiWrap::sendMessageFail(
 			link)));
 	} else if (error.type().startsWith(qstr("SLOWMODE_WAIT_"))) {
 		const auto chop = qstr("SLOWMODE_WAIT_").size();
-		const auto left = error.type().midRef(chop).toInt();
+		const auto left = base::StringViewMid(error.type(), chop).toInt();
 		if (const auto channel = peer->asChannel()) {
 			const auto seconds = channel->slowmodeSeconds();
 			if (seconds >= left) {
@@ -3263,7 +3263,7 @@ void ApiWrap::requestMessageAfterDate(
 	// So we request a message with offset_date = desired_date - 1 and add_offset = -1.
 	// This should give us the first message with date >= desired_date.
 	const auto offsetId = 0;
-	const auto offsetDate = static_cast<int>(base::QDateToDateTime(date).toTime_t()) - 1;
+	const auto offsetDate = static_cast<int>(date.startOfDay().toSecsSinceEpoch()) - 1;
 	const auto addOffset = -1;
 	const auto limit = 1;
 	const auto maxId = 0;

Telegram/SourceFiles/boxes/connection_box.cpp

@@ -74,7 +74,7 @@ void HostInput::correctValue(
 	QString newText;
 	int newCursor = nowCursor;
 	newText.reserve(now.size());
-	for (auto i = 0, l = now.size(); i < l; ++i) {
+	for (auto i = 0, l = int(now.size()); i < l; ++i) {
 		if (now[i] == ',') {
 			newText.append('.');
 		} else {
@@ -120,7 +120,7 @@ void Base64UrlInput::correctValue(
 	QString newText;
 	newText.reserve(now.size());
 	auto newPos = nowCursor;
-	for (auto i = 0, l = now.size(); i < l; ++i) {
+	for (auto i = 0, l = int(now.size()); i < l; ++i) {
 		const auto ch = now[i];
 		if ((ch >= '0' && ch <= '9')
 			|| (ch >= 'a' && ch <= 'z')
@@ -537,8 +537,8 @@ void ProxyRow::showMenu() {
 			_deleteClicks.fire({});
 		});
 	}
-	const auto parentTopLeft = window()->mapToGlobal({ 0, 0 });
-	const auto buttonTopLeft = _menuToggle->mapToGlobal({ 0, 0 });
+	const auto parentTopLeft = window()->mapToGlobal(QPoint());
+	const auto buttonTopLeft = _menuToggle->mapToGlobal(QPoint());
 	const auto parent = QRect(parentTopLeft, window()->size());
 	const auto button = QRect(buttonTopLeft, _menuToggle->size());
 	const auto bottom = button.y()

Telegram/SourceFiles/boxes/dictionaries_manager.cpp

@@ -39,11 +39,6 @@ using DictState = BlobState;
 using QueryCallback = Fn<void(const QString &)>;
 constexpr auto kMaxQueryLength = 15;
 
-#if QT_VERSION < QT_VERSION_CHECK(5, 10, 0)
-#define OLD_QT
-using QStringView = QString;
-#endif
-
 class Inner : public Ui::RpWidget {
 public:
 	Inner(

Telegram/SourceFiles/boxes/language_box.cpp

@@ -478,7 +478,7 @@ void Rows::showMenu(int index) {
 		}
 	}
 	const auto toggle = menuToggleArea(row);
-	const auto parentTopLeft = window()->mapToGlobal({ 0, 0 });
+	const auto parentTopLeft = window()->mapToGlobal(QPoint());
 	const auto buttonTopLeft = mapToGlobal(toggle.topLeft());
 	const auto parent = QRect(parentTopLeft, window()->size());
 	const auto button = QRect(buttonTopLeft, toggle.size());

Telegram/SourceFiles/boxes/passcode_box.cpp

@@ -32,6 +32,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_layers.h"
 #include "styles/style_passport.h"
 #include "styles/style_boxes.h"
+#include "base/qt_adapters.h"
 
 namespace {
 
@@ -525,7 +526,7 @@ void PasscodeBox::setPasswordFail(
 		const MTP::Error &error) {
 	const auto prefix = qstr("EMAIL_UNCONFIRMED_");
 	if (error.type().startsWith(prefix)) {
-		const auto codeLength = error.type().midRef(prefix.size()).toInt();
+		const auto codeLength = base::StringViewMid(error.type(), prefix.size()).toInt();
 
 		closeReplacedBy();
 		_setRequest = 0;

Telegram/SourceFiles/boxes/peer_list_box.cpp

@@ -1240,7 +1240,7 @@ int PeerListContent::resizeGetHeight(int newWidth) {
 	return belowTop + _belowHeight;
 }
 
-void PeerListContent::enterEventHook(QEvent *e) {
+void PeerListContent::enterEventHook(QEnterEvent *e) {
 	setMouseTracking(true);
 }
 

Telegram/SourceFiles/boxes/peer_list_box.h

@@ -622,7 +622,7 @@ protected:
 		int visibleBottom) override;
 
 	void paintEvent(QPaintEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 	void mouseMoveEvent(QMouseEvent *e) override;
 	void mousePressEvent(QMouseEvent *e) override;

Telegram/SourceFiles/boxes/peers/edit_participant_box.cpp

@@ -34,7 +34,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_user.h"
 #include "core/core_cloud_password.h"
 #include "base/unixtime.h"
-#include "base/qt_adapters.h"
 #include "apiwrap.h"
 #include "api/api_cloud_password.h"
 #include "main/main_session.h"
@@ -710,7 +709,7 @@ void EditRestrictedBox::showRestrictUntil() {
 			highlighted,
 			[this](const QDate &date) {
 				setRestrictUntil(
-					static_cast<int>(base::QDateToDateTime(date).toTime_t()));
+					static_cast<int>(date.startOfDay().toSecsSinceEpoch()));
 			}),
 		Ui::LayerOption::KeepOther);
 	_restrictUntilBox->setMaxDate(

Telegram/SourceFiles/boxes/share_box.cpp

@@ -72,7 +72,7 @@ protected:
 		int visibleBottom) override;
 
 	void paintEvent(QPaintEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 	void mouseMoveEvent(QMouseEvent *e) override;
 	void mousePressEvent(QMouseEvent *e) override;
@@ -906,7 +906,7 @@ void ShareBox::Inner::paintEvent(QPaintEvent *e) {
 	}
 }
 
-void ShareBox::Inner::enterEventHook(QEvent *e) {
+void ShareBox::Inner::enterEventHook(QEnterEvent *e) {
 	setMouseTracking(true);
 }
 

Telegram/SourceFiles/boxes/sticker_set_box.cpp

@@ -404,7 +404,7 @@ void StickerSetBox::Inner::gotSet(const MTPmessages_StickerSet &set) {
 
 					auto p = StickersPack();
 					p.reserve(stickers.size());
-					for (auto j = 0, c = stickers.size(); j != c; ++j) {
+					for (auto j = 0, c = int(stickers.size()); j != c; ++j) {
 						auto doc = _controller->session().data().document(stickers[j].v);
 						if (!doc || !doc->sticker()) continue;
 
@@ -532,7 +532,7 @@ void StickerSetBox::Inner::installDone(
 	auto &order = isMasks
 		? stickers.maskSetsOrderRef()
 		: stickers.setsOrderRef();
-	const auto insertAtIndex = 0, currentIndex = order.indexOf(_setId);
+	const auto insertAtIndex = 0, currentIndex = int(order.indexOf(_setId));
 	if (currentIndex != insertAtIndex) {
 		if (currentIndex > 0) {
 			order.removeAt(currentIndex);

Telegram/SourceFiles/calls/calls_panel.cpp

@@ -50,7 +50,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_calls.h"
 #include "styles/style_chat.h"
 
-#include <QtWidgets/QDesktopWidget>
 #include <QtWidgets/QApplication>
 #include <QtGui/QWindow>
 #include <QtCore/QTimer>

Telegram/SourceFiles/calls/calls_video_incoming.cpp

@@ -15,8 +15,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "webrtc/webrtc_video_track.h"
 #include "styles/style_calls.h"
 
-#include <QtGui/QOpenGLShader>
-#include <QtGui/QOpenGLBuffer>
+#include <QOpenGLShader>
+#include <QOpenGLBuffer>
 
 namespace Calls {
 namespace {

Telegram/SourceFiles/calls/group/calls_group_panel.cpp

@@ -55,7 +55,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_calls.h"
 #include "styles/style_layers.h"
 
-#include <QtWidgets/QDesktopWidget>
 #include <QtWidgets/QApplication>
 #include <QtGui/QWindow>
 #include <QtGui/QScreen>

Telegram/SourceFiles/calls/group/calls_group_viewport.cpp

@@ -26,7 +26,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_calls.h"
 
 #include <QtGui/QtEvents>
-#include <QtGui/QOpenGLShader>
+#include <QOpenGLShader>
 
 namespace Calls::Group {
 namespace {

Telegram/SourceFiles/calls/group/calls_group_viewport_opengl.cpp

@@ -16,7 +16,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_peer.h"
 #include "styles/style_calls.h"
 
-#include <QtGui/QOpenGLShader>
+#include <QOpenGLShader>
 
 namespace Calls::Group {
 namespace {

Telegram/SourceFiles/calls/group/calls_group_viewport_opengl.h

@@ -15,8 +15,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "ui/gl/gl_surface.h"
 #include "ui/gl/gl_image.h"
 
-#include <QtGui/QOpenGLBuffer>
-#include <QtGui/QOpenGLShaderProgram>
+#include <QOpenGLBuffer>
+#include <QOpenGLShaderProgram>
 
 namespace Webrtc {
 struct FrameWithInfo;

Telegram/SourceFiles/chat_helpers/bot_keyboard.cpp

@@ -160,7 +160,7 @@ void BotKeyboard::mouseReleaseEvent(QMouseEvent *e) {
 	}
 }
 
-void BotKeyboard::enterEventHook(QEvent *e) {
+void BotKeyboard::enterEventHook(QEnterEvent *e) {
 	_lastMousePos = QCursor::pos();
 	updateSelected();
 }

Telegram/SourceFiles/chat_helpers/bot_keyboard.h

@@ -74,7 +74,7 @@ protected:
 	void mousePressEvent(QMouseEvent *e) override;
 	void mouseMoveEvent(QMouseEvent *e) override;
 	void mouseReleaseEvent(QMouseEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 
 private:

Telegram/SourceFiles/chat_helpers/emoji_keywords.cpp

@@ -132,7 +132,7 @@ void CreateCacheFilePath() {
 			}
 			list.push_back(entry);
 		}
-		result.maxKeyLength = std::max(result.maxKeyLength, key.size());
+		result.maxKeyLength = std::max(result.maxKeyLength, int(key.size()));
 	}
 	result.version = version;
 	return result;

Telegram/SourceFiles/chat_helpers/emoji_list_widget.cpp

@@ -166,7 +166,7 @@ void EmojiColorPicker::showEmoji(EmojiPtr emoji) {
 	_ignoreShow = false;
 
 	_variants.resize(emoji->variantsCount() + 1);
-	for (auto i = 0, size = _variants.size(); i != size; ++i) {
+	for (auto i = 0, size = int(_variants.size()); i != size; ++i) {
 		_variants[i] = emoji->variant(i);
 	}
 
@@ -219,7 +219,7 @@ void EmojiColorPicker::paintEvent(QPaintEvent *e) {
 	p.fillRect(x, st::emojiPanMargins.top() + st::emojiColorsPadding, st::emojiColorsSep, inner.height() - st::emojiColorsPadding * 2, st::emojiColorsSepColor);
 
 	if (_variants.isEmpty()) return;
-	for (auto i = 0, count = _variants.size(); i != count; ++i) {
+	for (auto i = 0, count = int(_variants.size()); i != count; ++i) {
 		drawVariant(p, i);
 	}
 }

Telegram/SourceFiles/chat_helpers/emoji_suggestions_widget.cpp

@@ -495,7 +495,7 @@ void SuggestionsWidget::triggerRow(const Row &row) const {
 	_triggered.fire(row.emoji->text());
 }
 
-void SuggestionsWidget::enterEventHook(QEvent *e) {
+void SuggestionsWidget::enterEventHook(QEnterEvent *e) {
 	if (!inner().contains(mapToInner(QCursor::pos()))) {
 		clearMouseSelection();
 	}

Telegram/SourceFiles/chat_helpers/emoji_suggestions_widget.h

@@ -50,7 +50,7 @@ private:
 	void mouseMoveEvent(QMouseEvent *e) override;
 	void mousePressEvent(QMouseEvent *e) override;
 	void mouseReleaseEvent(QMouseEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 
 	void scrollByWheelEvent(not_null<QWheelEvent*> e);

Telegram/SourceFiles/chat_helpers/field_autocomplete.cpp

@@ -41,6 +41,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_chat.h"
 #include "styles/style_widgets.h"
 #include "styles/style_chat_helpers.h"
+#include "base/qt_adapters.h"
 
 #include <QtWidgets/QApplication>
 
@@ -84,7 +85,7 @@ private:
 	void paintEvent(QPaintEvent *e) override;
 	void resizeEvent(QResizeEvent *e) override;
 
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 
 	void mousePressEvent(QMouseEvent *e) override;
@@ -257,19 +258,19 @@ void FieldAutocomplete::showFiltered(
 
 	query = query.toLower();
 	auto type = Type::Stickers;
-	auto plainQuery = query.midRef(0);
+	auto plainQuery = QStringView(query);
 	switch (query.at(0).unicode()) {
 	case '@':
 		type = Type::Mentions;
-		plainQuery = query.midRef(1);
+		plainQuery = base::StringViewMid(query, 1);
 		break;
 	case '#':
 		type = Type::Hashtags;
-		plainQuery = query.midRef(1);
+		plainQuery = base::StringViewMid(query, 1);
 		break;
 	case '/':
 		type = Type::BotCommands;
-		plainQuery = query.midRef(1);
+		plainQuery = base::StringViewMid(query, 1);
 		break;
 	}
 	bool resetScroll = (_type != type || _filter != plainQuery);
@@ -1202,7 +1203,7 @@ void FieldAutocomplete::Inner::contextMenuEvent(QContextMenuEvent *e) {
 	}
 }
 
-void FieldAutocomplete::Inner::enterEventHook(QEvent *e) {
+void FieldAutocomplete::Inner::enterEventHook(QEnterEvent *e) {
 	setMouseTracking(true);
 }
 

Telegram/SourceFiles/chat_helpers/message_field.cpp

@@ -30,6 +30,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_layers.h"
 #include "styles/style_boxes.h"
 #include "styles/style_chat.h"
+#include "base/qt_adapters.h"
 
 #include <QtCore/QMimeData>
 #include <QtCore/QStack>
@@ -93,7 +94,7 @@ QString FieldTagMimeProcessor::tagFromMimeTag(const QString &mimeTag) {
 		const auto userId = _controller->session().userId();
 		auto match = QRegularExpression(":(\\d+)$").match(mimeTag);
 		if (!match.hasMatch()
-			|| match.capturedRef(1).toULongLong() != userId.bare) {
+			|| match.capturedView(1).toULongLong() != userId.bare) {
 			return QString();
 		}
 		return mimeTag.mid(0, mimeTag.size() - match.capturedLength());
@@ -380,7 +381,7 @@ InlineBotQuery ParseInlineBotQuery(
 					< inlineUsernameStart + inlineUsernameLength)) {
 				return InlineBotQuery();
 			}
-			auto username = text.midRef(inlineUsernameStart, inlineUsernameLength);
+			auto username = base::StringViewMid(text, inlineUsernameStart, inlineUsernameLength);
 			if (username != result.username) {
 				result.username = username.toString();
 				if (const auto peer = session->data().peerByUsername(result.username)) {
@@ -661,7 +662,7 @@ void MessageLinksParser::parse() {
 			}
 		}
 		const auto range = LinkRange {
-			domainOffset,
+			int(domainOffset),
 			static_cast<int>(p - start - domainOffset),
 			QString()
 		};
@@ -685,8 +686,8 @@ void MessageLinksParser::apply(
 	const auto current = _list.current();
 	const auto computeLink = [&](const LinkRange &range) {
 		return range.custom.isEmpty()
-			? text.midRef(range.start, range.length)
-			: range.custom.midRef(0);
+			? base::StringViewMid(text, range.start, range.length)
+			: QStringView(range.custom);
 	};
 	const auto changed = [&] {
 		if (current.size() != count) {

Telegram/SourceFiles/chat_helpers/spellchecker_common.cpp

@@ -184,7 +184,7 @@ void AddExceptions() {
 		return word.utf16();
 	}) | ranges::views::filter([](const auto &word) {
 		return !(Platform::Spellchecker::IsWordInDictionary(word)
-			|| Spellchecker::IsWordSkippable(&word));
+			|| Spellchecker::IsWordSkippable(word));
 	}) | ranges::to_vector;
 
 	ranges::for_each(exceptions, Platform::Spellchecker::AddWord);

Telegram/SourceFiles/chat_helpers/tabbed_panel.cpp

@@ -207,7 +207,7 @@ void TabbedPanel::moveByBottom() {
 	updateContentHeight();
 }
 
-void TabbedPanel::enterEventHook(QEvent *e) {
+void TabbedPanel::enterEventHook(QEnterEvent *e) {
 	Core::App().registerLeaveSubscription(this);
 	showAnimated();
 }

Telegram/SourceFiles/chat_helpers/tabbed_panel.h

@@ -58,7 +58,7 @@ public:
 	~TabbedPanel();
 
 protected:
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 	void otherEnter();
 	void otherLeave();

Telegram/SourceFiles/core/application.cpp

@@ -25,6 +25,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "core/ui_integration.h"
 #include "chat_helpers/emoji_keywords.h"
 #include "chat_helpers/stickers_emoji_image_loader.h"
+#include "base/qt_adapters.h"
 #include "base/platform/base_platform_url_scheme.h"
 #include "base/platform/base_platform_last_input.h"
 #include "base/platform/base_platform_info.h"
@@ -83,7 +84,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "boxes/share_box.h"
 #include "app.h"
 
-#include <QtWidgets/QDesktopWidget>
 #include <QtCore/QMimeDatabase>
 #include <QtGui/QGuiApplication>
 #include <QtGui/QScreen>
@@ -830,7 +830,7 @@ bool Application::openCustomUrl(
 		|| passcodeLocked()) {
 		return false;
 	}
-	const auto command = urlTrimmed.midRef(protocol.size(), 8192);
+	const auto command = base::StringViewMid(urlTrimmed, protocol.size(), 8192);
 	const auto controller = _window ? _window->sessionController() : nullptr;
 
 	using namespace qthelp;

Telegram/SourceFiles/core/changelogs.cpp

@@ -13,6 +13,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "main/main_session.h"
 #include "storage/storage_domain.h"
 #include "data/data_session.h"
+#include "base/qt_adapters.h"
 #include "mainwindow.h"
 #include "apiwrap.h"
 
@@ -194,7 +195,7 @@ void Changelogs::addBetaLog(int changeVersion, const char *changes) {
 		static const auto simple = u"\n- "_q;
 		static const auto separator = QString::fromUtf8("\n\xE2\x80\xA2 ");
 		auto result = QString::fromUtf8(changes).trimmed();
-		if (result.startsWith(simple.midRef(1))) {
+		if (result.startsWith(base::StringViewMid(simple, 1))) {
 			result = separator.mid(1) + result.mid(simple.size() - 1);
 		}
 		return result.replace(simple, separator);

Telegram/SourceFiles/core/launcher.cpp

@@ -288,6 +288,7 @@ void Launcher::init() {
 	QApplication::setApplicationName(qsl("TelegramDesktop"));
 	QApplication::setAttribute(Qt::AA_DisableHighDpiScaling, true);
 
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 	// fallback session management is useless for tdesktop since it doesn't have
 	// any "are you sure you want to close this window?" dialogs
 	// but it produces bugs like https://github.com/telegramdesktop/tdesktop/issues/5022
@@ -295,6 +296,7 @@ void Launcher::init() {
 	// and https://github.com/telegramdesktop/tdesktop/issues/948
 	// more info: https://doc.qt.io/qt-5/qguiapplication.html#isFallbackSessionManagementEnabled
 	QApplication::setFallbackSessionManagementEnabled(false);
+#endif // Qt < 6.0.0
 
 	initHook();
 }
@@ -402,7 +404,7 @@ void Launcher::prepareSettings() {
 	if (!path.isEmpty()) {
 		auto info = QFileInfo(path);
 		if (info.isSymLink()) {
-			info = info.symLinkTarget();
+			info = QFileInfo(info.symLinkTarget());
 		}
 		if (info.exists()) {
 			const auto dir = info.absoluteDir().absolutePath();

Telegram/SourceFiles/core/local_url_handlers.cpp

@@ -41,6 +41,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "main/main_session.h"
 #include "main/main_session_settings.h"
 #include "history/history.h"
+#include "base/qt_adapters.h"
 #include "apiwrap.h"
 
 #include <QtGui/QGuiApplication>
@@ -100,7 +101,7 @@ bool SetLanguage(
 		Window::SessionController *controller,
 		const Match &match,
 		const QVariant &context) {
-	if (match->capturedRef(1).isEmpty()) {
+	if (match->capturedView(1).isEmpty()) {
 		ShowLanguagesBox();
 	} else {
 		const auto languageId = match->captured(2);
@@ -688,7 +689,7 @@ QString TryConvertUrlToLocal(QString url) {
 	auto matchOptions = RegExOption::CaseInsensitive;
 	auto telegramMeMatch = regex_match(qsl("^(https?://)?(www\\.)?(telegram\\.(me|dog)|t\\.me)/(.+)$"), url, matchOptions);
 	if (telegramMeMatch) {
-		auto query = telegramMeMatch->capturedRef(5);
+		auto query = telegramMeMatch->capturedView(5);
 		if (auto joinChatMatch = regex_match(qsl("^(joinchat/|\\+|\\%20)([a-zA-Z0-9\\.\\_\\-]+)(\\?|$)"), query, matchOptions)) {
 			return qsl("tg://join?invite=") + url_encode(joinChatMatch->captured(2));
 		} else if (auto stickerSetMatch = regex_match(qsl("^addstickers/([a-zA-Z0-9\\.\\_]+)(\\?|$)"), query, matchOptions)) {
@@ -746,7 +747,7 @@ bool InternalPassportLink(const QString &url) {
 	if (!urlTrimmed.startsWith(qstr("tg://"), Qt::CaseInsensitive)) {
 		return false;
 	}
-	const auto command = urlTrimmed.midRef(qstr("tg://").size());
+	const auto command = base::StringViewMid(urlTrimmed, qstr("tg://").size());
 
 	using namespace qthelp;
 	const auto matchOptions = RegExOption::CaseInsensitive;

Telegram/SourceFiles/core/sandbox.cpp

@@ -265,7 +265,10 @@ void Sandbox::socketReading() {
 	}
 	_localSocketReadData.append(_localSocket.readAll());
 	if (QRegularExpression("RES:(\\d+);").match(_localSocketReadData).hasMatch()) {
-		uint64 pid = _localSocketReadData.midRef(4, _localSocketReadData.length() - 5).toULongLong();
+		uint64 pid = base::StringViewMid(
+			_localSocketReadData,
+			4,
+			_localSocketReadData.length() - 5).toULongLong();
 		if (pid != kEmptyPidForCommandResponse) {
 			psActivateProcess(pid);
 		}
@@ -388,7 +391,7 @@ void Sandbox::readClients() {
 			QString cmds(QString::fromLatin1(i->second));
 			int32 from = 0, l = cmds.length();
 			for (int32 to = cmds.indexOf(QChar(';'), from); to >= from; to = (from < l) ? cmds.indexOf(QChar(';'), from) : -1) {
-				QStringRef cmd(&cmds, from, to - from);
+				auto cmd = base::StringViewMid(cmds, from, to - from);
 				if (cmd.startsWith(qsl("CMD:"))) {
 					execExternal(cmds.mid(from + 4, to - from - 4));
 					const auto response = qsl("RES:%1;").arg(QApplication::applicationPid()).toLatin1();
@@ -409,7 +412,7 @@ void Sandbox::readClients() {
 					const auto response = qsl("RES:%1;").arg(responsePid).toLatin1();
 					i->first->write(response.data(), response.size());
 				} else {
-					LOG(("Sandbox Error: unknown command %1 passed in local socket").arg(QString(cmd.constData(), cmd.length())));
+					LOG(("Sandbox Error: unknown command %1 passed in local socket").arg(cmd.toString()));
 				}
 				from = to + 1;
 			}
@@ -571,7 +574,7 @@ void Sandbox::processPostponedCalls(int level) {
 bool Sandbox::nativeEventFilter(
 		const QByteArray &eventType,
 		void *message,
-		long *result) {
+		base::NativeEventResult *result) {
 	registerEnterFromEventLoop();
 	return false;
 }

Telegram/SourceFiles/core/sandbox.h

@@ -8,6 +8,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #pragma once
 
 #include "mtproto/mtproto_proxy_data.h"
+#include "base/qt_adapters.h"
 
 #include <QtWidgets/QApplication>
 #include <QtNetwork/QLocalServer>
@@ -85,7 +86,7 @@ private:
 	bool nativeEventFilter(
 		const QByteArray &eventType,
 		void *message,
-		long *result) override;
+		base::NativeEventResult *result) override;
 	void processPostponedCalls(int level);
 	void singleInstanceChecked();
 	void launchApplication();

Telegram/SourceFiles/core/shortcuts.cpp

@@ -16,7 +16,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "platform/platform_specific.h"
 #include "base/parse_helper.h"
 
-#include <QtWidgets/QShortcut>
+#include <QShortcut>
 #include <QtCore/QJsonDocument>
 #include <QtCore/QJsonObject>
 #include <QtCore/QJsonArray>

Telegram/SourceFiles/core/update_checker.cpp

@@ -582,7 +582,7 @@ bool ParseCommonMap(
 			if ((*version).isString()) {
 				const auto string = (*version).toString();
 				if (const auto index = string.indexOf(':'); index > 0) {
-					return string.midRef(0, index).toULongLong();
+					return base::StringViewMid(string, 0, index).toULongLong();
 				}
 				return string.toULongLong();
 			} else if ((*version).isDouble()) {
@@ -1014,7 +1014,7 @@ auto MtpChecker::parseText(const QByteArray &text) const
 			return false;
 		}
 		bestLocation.username = full.mid(start + 1, post - start - 1);
-		bestLocation.postId = full.midRef(post + 1).toInt();
+		bestLocation.postId = base::StringViewMid(full, post + 1).toInt();
 		if (bestLocation.username.isEmpty() || !bestLocation.postId) {
 			LOG(("Update Error: MTP entry '%1' is bad for version %2."
 				).arg(full

Telegram/SourceFiles/countries/countries_instance.cpp

@@ -7,6 +7,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #include "countries/countries_instance.h"
 
+#include "base/qt_adapters.h"
+
 namespace Countries {
 namespace {
 
@@ -328,11 +330,11 @@ FormatResult CountriesInstance::format(FormatArgs args) {
 			if (phoneNumber.startsWith(callingCode.callingCode)) {
 				const auto codeSize = callingCode.callingCode.size();
 				for (const auto &prefix : callingCode.prefixes) {
-					if (prefix.startsWith(phoneNumber.midRef(codeSize))) {
+					if (prefix.startsWith(base::StringViewMid(phoneNumber, codeSize))) {
 						isPrefix = true;
 					}
 					if ((codeSize + prefix.size()) > bestLength &&
-							phoneNumber.midRef(codeSize).startsWith(prefix)) {
+							base::StringViewMid(phoneNumber, codeSize).startsWith(prefix)) {
 						bestCountryPtr = &country;
 						bestCallingCodePtr = &callingCode;
 						bestLength = codeSize + prefix.size();

Telegram/SourceFiles/data/data_document.cpp

@@ -988,7 +988,7 @@ QByteArray documentWaveformEncode5bit(const VoiceWaveform &waveform) {
 	// Write each 0-31 unsigned char as 5 bit to result.
 	// We reserve one extra byte to be able to dereference any of required bytes
 	// as a uint16 without overflowing, even the byte with index "bytesCount - 1".
-	for (auto i = 0, l = waveform.size(); i < l; ++i) {
+	for (auto i = 0, l = int(waveform.size()); i < l; ++i) {
 		auto byteIndex = (i * 5) / 8;
 		auto bitShift = (i * 5) % 8;
 		auto value = (static_cast<uint16>(waveform[i]) & 0x1F) << bitShift;
@@ -1337,7 +1337,7 @@ bool DocumentData::isAudioFile() const {
 		}
 		return false;
 	}
-	const auto left = _mimeString.midRef(prefix.size()).toString();
+	const auto left = _mimeString.mid(prefix.size());
 	const auto types = { qstr("x-wav"), qstr("wav"), qstr("mp4") };
 	return ranges::contains(types, left);
 }

Telegram/SourceFiles/data/data_document_resolver.cpp

@@ -232,7 +232,7 @@ void ResolveDocument(
 				location.accessDisable();
 			});
 			const auto path = location.name();
-			if (Core::MimeTypeForFile(path).name().startsWith("image/")
+			if (Core::MimeTypeForFile(QFileInfo(path)).name().startsWith("image/")
 				&& QImageReader(path).canRead()) {
 				showDocument();
 				return true;

Telegram/SourceFiles/data/data_peer_values.cpp

@@ -12,7 +12,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_chat.h"
 #include "data/data_user.h"
 #include "base/unixtime.h"
-#include "base/qt_adapters.h"
 
 namespace Data {
 namespace {
@@ -40,7 +39,7 @@ int OnlinePhraseChangeInSeconds(TimeId online, TimeId now) {
 		return (hours + 1) * 3600 - (now - online);
 	}
 	const auto nowFull = base::unixtime::parse(now);
-	const auto tomorrow = base::QDateToDateTime(nowFull.date().addDays(1));
+	const auto tomorrow = nowFull.date().addDays(1).startOfDay();
 	return std::max(static_cast<TimeId>(nowFull.secsTo(tomorrow)), 0);
 }
 

Telegram/SourceFiles/data/data_web_page.cpp

@@ -14,7 +14,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_photo.h"
 #include "data/data_channel.h"
 #include "data/data_document.h"
-#include "base/qt_adapters.h"
 #include "ui/image/image.h"
 #include "ui/text/text_entity.h"
 
@@ -27,7 +26,7 @@ QString SiteNameFromUrl(const QString &url) {
 	if (m.hasMatch()) pretty = pretty.mid(m.capturedLength());
 	int32 slash = pretty.indexOf('/');
 	if (slash > 0) pretty = pretty.mid(0, slash);
-	QStringList components = pretty.split('.', base::QStringSkipEmptyParts);
+	QStringList components = pretty.split('.', Qt::SkipEmptyParts);
 	if (components.size() >= 2) {
 		components = components.mid(components.size() - 2);
 		return components.at(0).at(0).toUpper() + components.at(0).mid(1) + '.' + components.at(1);

Telegram/SourceFiles/data/stickers/data_stickers.cpp

@@ -679,7 +679,7 @@ void Stickers::setPackAndEmoji(
 
 			auto p = StickersPack();
 			p.reserve(stickers.size());
-			for (auto j = 0, c = stickers.size(); j != c; ++j) {
+			for (auto j = 0, c = int(stickers.size()); j != c; ++j) {
 				auto document = owner().document(stickers[j].v);
 				if (!document || !document->sticker()) continue;
 
@@ -1302,7 +1302,7 @@ StickersSet *Stickers::feedSetFull(const MTPmessages_StickerSet &data) {
 		set->stickers = pack;
 		set->emoji.clear();
 		auto &v = d.vpacks().v;
-		for (auto i = 0, l = v.size(); i != l; ++i) {
+		for (auto i = 0, l = int(v.size()); i != l; ++i) {
 			if (v[i].type() != mtpc_stickerPack) continue;
 
 			auto &pack = v[i].c_stickerPack();
@@ -1312,7 +1312,7 @@ StickersSet *Stickers::feedSetFull(const MTPmessages_StickerSet &data) {
 
 				StickersPack p;
 				p.reserve(stickers.size());
-				for (auto j = 0, c = stickers.size(); j != c; ++j) {
+				for (auto j = 0, c = int(stickers.size()); j != c; ++j) {
 					auto doc = owner().document(stickers[j].v);
 					if (!doc || !doc->sticker()) continue;
 

Telegram/SourceFiles/dialogs/dialogs_inner_widget.cpp

@@ -52,6 +52,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_dialogs.h"
 #include "styles/style_chat_helpers.h"
 #include "styles/style_window.h"
+#include "base/qt_adapters.h"
 
 namespace Dialogs {
 namespace {
@@ -1619,7 +1620,7 @@ void InnerWidget::updateDialogRow(
 	}
 }
 
-void InnerWidget::enterEventHook(QEvent *e) {
+void InnerWidget::enterEventHook(QEnterEvent *e) {
 	setMouseTracking(true);
 }
 
@@ -1844,7 +1845,7 @@ void InnerWidget::applyFilterUpdate(QString newFilter, bool force) {
 	}
 }
 
-void InnerWidget::onHashtagFilterUpdate(QStringRef newFilter) {
+void InnerWidget::onHashtagFilterUpdate(QStringView newFilter) {
 	if (newFilter.isEmpty() || newFilter.at(0) != '#' || _searchInChat) {
 		_hashtagFilter = QString();
 		if (!_hashtagResults.empty()) {
@@ -1863,7 +1864,7 @@ void InnerWidget::onHashtagFilterUpdate(QStringRef newFilter) {
 	if (!recent.isEmpty()) {
 		_hashtagResults.reserve(qMin(recent.size(), kHashtagResultsLimit));
 		for (const auto &tag : recent) {
-			if (tag.first.startsWith(_hashtagFilter.midRef(1), Qt::CaseInsensitive)
+			if (tag.first.startsWith(base::StringViewMid(_hashtagFilter, 1), Qt::CaseInsensitive)
 				&& tag.first.size() + 1 != newFilter.size()) {
 				_hashtagResults.push_back(std::make_unique<HashtagResult>(tag.first));
 				if (_hashtagResults.size() == kHashtagResultsLimit) break;
@@ -2291,7 +2292,7 @@ void InnerWidget::searchInChat(Key key, PeerData *from) {
 	_searchFromPeer = from;
 	if (_searchInChat) {
 		_controller->closeFolder();
-		onHashtagFilterUpdate(QStringRef());
+		onHashtagFilterUpdate(QStringView());
 		_cancelSearchInChat->show();
 		refreshSearchInChatLabel();
 	} else {

Telegram/SourceFiles/dialogs/dialogs_inner_widget.h

@@ -114,7 +114,7 @@ public:
 	void searchInChat(Key key, PeerData *from);
 
 	void applyFilterUpdate(QString newFilter, bool force = false);
-	void onHashtagFilterUpdate(QStringRef newFilter);
+	void onHashtagFilterUpdate(QStringView newFilter);
 
 	PeerData *updateFromParentDrag(QPoint globalPosition);
 
@@ -148,7 +148,7 @@ protected:
 	void mousePressEvent(QMouseEvent *e) override;
 	void mouseReleaseEvent(QMouseEvent *e) override;
 	void resizeEvent(QResizeEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 	void contextMenuEvent(QContextMenuEvent *e) override;
 

Telegram/SourceFiles/dialogs/dialogs_widget.cpp

@@ -51,6 +51,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_chat.h"
 #include "styles/style_info.h"
 #include "styles/style_window.h"
+#include "base/qt_adapters.h"
 
 #include <QtCore/QMimeData>
 
@@ -1475,12 +1476,12 @@ void Widget::showSearchFrom() {
 void Widget::onFilterCursorMoved(int from, int to) {
 	if (to < 0) to = _filter->cursorPosition();
 	QString t = _filter->getLastText();
-	QStringRef r;
+	QStringView r;
 	for (int start = to; start > 0;) {
 		--start;
 		if (t.size() <= start) break;
 		if (t.at(start) == '#') {
-			r = t.midRef(start, to - start);
+			r = base::StringViewMid(t, start, to - start);
 			break;
 		}
 		if (!t.at(start).isLetterOrNumber() && t.at(start) != '_') break;
@@ -1495,7 +1496,9 @@ void Widget::onCompleteHashtag(QString tag) {
 		--start;
 		if (t.size() <= start) break;
 		if (t.at(start) == '#') {
-			if (cur == start + 1 || t.midRef(start + 1, cur - start - 1) == tag.midRef(0, cur - start - 1)) {
+			if (cur == start + 1
+				|| base::StringViewMid(t, start + 1, cur - start - 1)
+					== base::StringViewMid(tag, 0, cur - start - 1)) {
 				for (; cur < t.size() && cur - start - 1 < tag.size(); ++cur) {
 					if (t.at(cur) != tag.at(cur - start - 1)) break;
 				}

Telegram/SourceFiles/editor/editor_crop.cpp

@@ -92,7 +92,7 @@ void Crop::applyTransform(
 	const auto cropHolder = QRectF(QPointF(), scaledImageSize);
 	const auto cropHolderCenter = cropHolder.center();
 
-	auto matrix = QMatrix()
+	auto matrix = QTransform()
 		.translate(cropHolderCenter.x(), cropHolderCenter.y())
 		.scale(flipped ? -1 : 1, 1)
 		.rotate(angle)
@@ -151,12 +151,12 @@ void Crop::setCropPaint(QRectF &&rect) {
 }
 
 void Crop::convertCropPaintToOriginal() {
-	const auto cropHolder = QMatrix()
+	const auto cropHolder = QTransform()
 		.scale(_ratio.w, _ratio.h)
 		.mapRect(QRectF(QPointF(), FlipSizeByRotation(_imageSize, _angle)));
 	const auto cropHolderCenter = cropHolder.center();
 
-	const auto matrix = QMatrix()
+	const auto matrix = QTransform()
 		.translate(cropHolderCenter.x(), cropHolderCenter.y())
 		.rotate(-_angle)
 		.scale((_flipped ? -1 : 1) * 1. / _ratio.w, 1. / _ratio.h)

Telegram/SourceFiles/editor/editor_paint.cpp

@@ -133,7 +133,7 @@ void Paint::applyTransform(QRect geometry, int angle, bool flipped) {
 	setGeometry(geometry);
 	const auto size = geometry.size();
 
-	const auto rotatedImageSize = QMatrix()
+	const auto rotatedImageSize = QTransform()
 		.rotate(angle)
 		.mapRect(QRect(QPoint(), _imageSize));
 

Telegram/SourceFiles/export/data/export_data_types.cpp

@@ -177,7 +177,7 @@ Utf8String FillLeft(const Utf8String &data, int length, char filler) {
 	}
 	auto result = Utf8String();
 	result.reserve(length);
-	for (auto i = 0, count = length - data.size(); i != count; ++i) {
+	for (auto i = 0, count = length - int(data.size()); i != count; ++i) {
 		result.append(filler);
 	}
 	result.append(data);
@@ -1806,7 +1806,7 @@ Utf8String FormatDateTime(
 	if (!date) {
 		return Utf8String();
 	}
-	const auto value = QDateTime::fromTime_t(date);
+	const auto value = QDateTime::fromSecsSinceEpoch(date);
 	return (QString("%1") + dateSeparator + "%2" + dateSeparator + "%3"
 		+ separator + "%4" + timeSeparator + "%5" + timeSeparator + "%6"
 	).arg(value.date().day(), 2, 10, QChar('0')

Telegram/SourceFiles/export/export_api_wrap.cpp

@@ -736,7 +736,7 @@ void ApiWrap::requestUserpics(
 
 		auto startInfo = result.match(
 		[](const MTPDphotos_photos &data) {
-			return Data::UserpicsInfo{ data.vphotos().v.size() };
+			return Data::UserpicsInfo{ int(data.vphotos().v.size()) };
 		}, [](const MTPDphotos_photosSlice &data) {
 			return Data::UserpicsInfo{ data.vcount().v };
 		});
@@ -968,7 +968,7 @@ void ApiWrap::requestMessagesCount(int localSplitIndex) {
 
 		const auto count = result.match(
 			[](const MTPDmessages_messages &data) {
-			return data.vmessages().v.size();
+			return int(data.vmessages().v.size());
 		}, [](const MTPDmessages_messagesSlice &data) {
 			return data.vcount().v;
 		}, [](const MTPDmessages_channelMessages &data) {

Telegram/SourceFiles/export/output/export_output_file.cpp

@@ -9,6 +9,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 
 #include "export/output/export_output_result.h"
 #include "export/output/export_output_stats.h"
+#include "base/qt_adapters.h"
 
 #include <QtCore/QFileInfo>
 #include <QtCore/QDir>
@@ -102,10 +103,10 @@ QString File::PrepareRelativePath(
 
 	// Not lastIndexOf('.') so that "file.tar.xz" won't be messed up.
 	const auto position = suggested.indexOf('.');
-	const auto base = suggested.midRef(0, position).toString();
+	const auto base = suggested.mid(0, position);
 	const auto extension = (position >= 0)
-		? suggested.midRef(position)
-		: QStringRef();
+		? base::StringViewMid(suggested, position)
+		: QStringView();
 	const auto relativePart = [&](int attempt) {
 		auto result = base + QString(" (%1)").arg(attempt);
 		result.append(extension);

Telegram/SourceFiles/export/output/export_output_html.cpp

@@ -283,12 +283,12 @@ bool DisplayDate(TimeId date, TimeId previousDate) {
 	if (!previousDate) {
 		return true;
 	}
-	return QDateTime::fromTime_t(date).date()
-		!= QDateTime::fromTime_t(previousDate).date();
+	return QDateTime::fromSecsSinceEpoch(date).date()
+		!= QDateTime::fromSecsSinceEpoch(previousDate).date();
 }
 
 QByteArray FormatDateText(TimeId date) {
-	const auto parsed = QDateTime::fromTime_t(date).date();
+	const auto parsed = QDateTime::fromSecsSinceEpoch(date).date();
 	const auto month = [](int index) {
 		switch (index) {
 		case 1: return "January";
@@ -314,7 +314,7 @@ QByteArray FormatDateText(TimeId date) {
 }
 
 QByteArray FormatTimeText(TimeId date) {
-	const auto parsed = QDateTime::fromTime_t(date).time();
+	const auto parsed = QDateTime::fromSecsSinceEpoch(date).time();
 	return Data::NumberToString(parsed.hour(), 2)
 		+ ':'
 		+ Data::NumberToString(parsed.minute(), 2);
@@ -1256,8 +1256,8 @@ bool HtmlWriter::Wrap::messageNeedsWrap(
 		return true;
 	} else if (message.viaBotId != previous->viaBotId) {
 		return true;
-	} else if (QDateTime::fromTime_t(previous->date).date()
-		!= QDateTime::fromTime_t(message.date).date()) {
+	} else if (QDateTime::fromSecsSinceEpoch(previous->date).date()
+		!= QDateTime::fromSecsSinceEpoch(message.date).date()) {
 		return true;
 	} else if (message.forwarded != previous->forwarded
 		|| message.showForwardedAsOriginal != previous->showForwardedAsOriginal

Telegram/SourceFiles/export/output/export_output_json.cpp

@@ -71,7 +71,7 @@ QByteArray SerializeString(const QByteArray &value) {
 
 QByteArray SerializeDate(TimeId date) {
 	return SerializeString(
-		QDateTime::fromTime_t(date).toString(Qt::ISODate).toUtf8());
+		QDateTime::fromSecsSinceEpoch(date).toString(Qt::ISODate).toUtf8());
 }
 
 QByteArray StringAllowEmpty(const Data::Utf8String &data) {

Telegram/SourceFiles/export/view/export_view_panel_controller.cpp

@@ -23,6 +23,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "data/data_session.h"
 #include "base/platform/base_platform_info.h"
 #include "base/unixtime.h"
+#include "base/qt_adapters.h"
 #include "styles/style_export.h"
 #include "styles/style_layers.h"
 
@@ -219,7 +220,8 @@ void PanelController::showError(const ApiErrorState &error) {
 	if (error.data.type() == qstr("TAKEOUT_INVALID")) {
 		showError(tr::lng_export_invalid(tr::now));
 	} else if (error.data.type().startsWith(qstr("TAKEOUT_INIT_DELAY_"))) {
-		const auto seconds = std::max(error.data.type().midRef(
+		const auto seconds = std::max(base::StringViewMid(
+			error.data.type(),
 			qstr("TAKEOUT_INIT_DELAY_").size()).toInt(), 1);
 		const auto now = QDateTime::currentDateTime();
 		const auto when = now.addSecs(seconds);

Telegram/SourceFiles/export/view/export_view_settings.cpp

@@ -25,7 +25,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "platform/platform_specific.h"
 #include "core/file_utilities.h"
 #include "base/unixtime.h"
-#include "base/qt_adapters.h"
 #include "main/main_session.h"
 #include "styles/style_widgets.h"
 #include "styles/style_export.h"
@@ -479,7 +478,7 @@ void SettingsWidget::editDateLimit(
 		}));
 	};
 	const auto callback = crl::guard(this, [=](const QDate &date) {
-		done(base::unixtime::serialize(base::QDateToDateTime(date)));
+		done(base::unixtime::serialize(date.startOfDay()));
 		if (const auto weak = shared->data()) {
 			weak->closeBox();
 		}

Telegram/SourceFiles/ffmpeg/ffmpeg_utility.cpp

@@ -56,13 +56,10 @@ void UnPremultiplyLine(uchar *dst, const uchar *src, int intsCount) {
 	for (auto i = 0; i != intsCount; ++i) {
 		udst[i] = qUnpremultiply(usrc[i]);
 	}
-#elif QT_VERSION < QT_VERSION_CHECK(5, 12, 0)
-	static const auto layout = &qPixelLayouts[QImage::Format_ARGB32];
-	layout->convertFromARGB32PM(udst, usrc, intsCount, layout, nullptr);
-#else // Qt >= 5.12
+#else // !LIB_FFMPEG_USE_QT_PRIVATE_API
 	static const auto layout = &qPixelLayouts[QImage::Format_ARGB32];
 	layout->storeFromARGB32PM(dst, usrc, 0, intsCount, nullptr, nullptr);
-#endif // Qt >= 5.12
+#endif // LIB_FFMPEG_USE_QT_PRIVATE_API
 }
 
 void PremultiplyLine(uchar *dst, const uchar *src, int intsCount) {
@@ -73,13 +70,10 @@ void PremultiplyLine(uchar *dst, const uchar *src, int intsCount) {
 	for (auto i = 0; i != intsCount; ++i) {
 		udst[i] = qPremultiply(usrc[i]);
 	}
-#elif QT_VERSION < QT_VERSION_CHECK(5, 12, 0)
-	static const auto layout = &qPixelLayouts[QImage::Format_ARGB32];
-	layout->convertToARGB32PM(udst, usrc, intsCount, layout, nullptr);
-#else // Qt >= 5.12
+#else // !LIB_FFMPEG_USE_QT_PRIVATE_API
 	static const auto layout = &qPixelLayouts[QImage::Format_ARGB32];
 	layout->fetchToARGB32PM(udst, src, 0, intsCount, nullptr, nullptr);
-#endif // Qt >= 5.12
+#endif // LIB_FFMPEG_USE_QT_PRIVATE_API
 }
 
 } // namespace

Telegram/SourceFiles/history/admin_log/history_admin_log_inner.cpp

@@ -1464,7 +1464,7 @@ void InnerWidget::mouseReleaseEvent(QMouseEvent *e) {
 	}
 }
 
-void InnerWidget::enterEventHook(QEvent *e) {
+void InnerWidget::enterEventHook(QEnterEvent *e) {
 	mouseActionUpdate(QCursor::pos());
 	return TWidget::enterEventHook(e);
 }

Telegram/SourceFiles/history/admin_log/history_admin_log_inner.h

@@ -153,7 +153,7 @@ protected:
 	void mouseMoveEvent(QMouseEvent *e) override;
 	void mouseReleaseEvent(QMouseEvent *e) override;
 	void mouseDoubleClickEvent(QMouseEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 	void contextMenuEvent(QContextMenuEvent *e) override;
 

Telegram/SourceFiles/history/admin_log/history_admin_log_item.cpp

@@ -38,7 +38,7 @@ TextWithEntities PrepareText(const QString &value, const QString &emptyValue) {
 			result.entities.push_back({
 				EntityType::Italic,
 				0,
-				emptyValue.size() });
+				int(emptyValue.size()) });
 		}
 	} else {
 		TextUtilities::ParseEntities(result, TextParseLinks | TextParseMentions | TextParseHashtags | TextParseBotCommands);
@@ -296,7 +296,7 @@ TextWithEntities GenerateInviteLinkChangeText(
 		link.entities.push_back({
 			EntityType::CustomUrl,
 			0,
-			link.text.size(),
+			int(link.text.size()),
 			InternalInviteLinkUrl(newLink) });
 	}
 	auto result = tr::lng_admin_log_edited_invite_link(tr::now, lt_link, link, Ui::Text::WithEntities);
@@ -350,7 +350,7 @@ auto GenerateParticipantString(
 		name.entities.push_back({
 			EntityType::MentionName,
 			0,
-			name.text.size(),
+			int(name.text.size()),
 			entityData });
 	}
 	auto username = peer->userName();
@@ -361,7 +361,7 @@ auto GenerateParticipantString(
 	mention.entities.push_back({
 		EntityType::Mention,
 		0,
-		mention.text.size() });
+		int(mention.text.size()) });
 	return tr::lng_admin_log_user_with_username(
 		tr::now,
 		lt_name,

Telegram/SourceFiles/history/history.cpp

@@ -49,6 +49,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "core/crash_reports.h"
 #include "core/application.h"
 #include "base/unixtime.h"
+#include "base/qt_adapters.h"
 #include "styles/style_dialogs.h"
 
 namespace {
@@ -2655,10 +2656,10 @@ void History::cacheTopPromotion(
 	}
 }
 
-QStringRef History::topPromotionType() const {
+QStringView History::topPromotionType() const {
 	return topPromotionAboutShown()
-		? _topPromotedType.midRef(5)
-		: _topPromotedType.midRef(0);
+		? base::StringViewMid(_topPromotedType, 5)
+		: QStringView(_topPromotedType);
 }
 
 bool History::topPromotionAboutShown() const {

Telegram/SourceFiles/history/history.h

@@ -277,7 +277,7 @@ public:
 		bool promoted,
 		const QString &type,
 		const QString &message);
-	[[nodiscard]] QStringRef topPromotionType() const;
+	[[nodiscard]] QStringView topPromotionType() const;
 	[[nodiscard]] QString topPromotionMessage() const;
 	[[nodiscard]] bool topPromotionAboutShown() const;
 	void markTopPromotionAboutShown();

Telegram/SourceFiles/history/history_inner_widget.cpp

@@ -76,6 +76,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "app.h"
 #include "styles/style_chat.h"
 #include "styles/style_window.h" // st::windowMinWidth
+#include "base/qt_adapters.h"
 
 #include <QtGui/QClipboard>
 #include <QtWidgets/QApplication>
@@ -866,7 +867,7 @@ bool HistoryInner::eventHook(QEvent *e) {
 		|| e->type() == QEvent::TouchEnd
 		|| e->type() == QEvent::TouchCancel) {
 		QTouchEvent *ev = static_cast<QTouchEvent*>(e);
-		if (ev->device()->type() == QTouchDevice::TouchScreen) {
+		if (ev->device()->type() == base::TouchDevice::TouchScreen) {
 			touchEvent(ev);
 			return true;
 		}
@@ -2504,7 +2505,7 @@ void HistoryInner::updateSize() {
 	}
 }
 
-void HistoryInner::enterEventHook(QEvent *e) {
+void HistoryInner::enterEventHook(QEnterEvent *e) {
 	mouseActionUpdate(QCursor::pos());
 	return TWidget::enterEventHook(e);
 }

Telegram/SourceFiles/history/history_inner_widget.h

@@ -167,7 +167,7 @@ protected:
 	void mousePressEvent(QMouseEvent *e) override;
 	void mouseReleaseEvent(QMouseEvent *e) override;
 	void mouseDoubleClickEvent(QMouseEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 	void resizeEvent(QResizeEvent *e) override;
 	void keyPressEvent(QKeyEvent *e) override;

Telegram/SourceFiles/history/history_item_components.cpp

@@ -32,7 +32,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "main/main_session.h"
 #include "window/window_session_controller.h"
 #include "facades.h"
-#include "base/qt_adapters.h"
 #include "styles/style_widgets.h"
 #include "styles/style_chat.h"
 
@@ -136,7 +135,7 @@ HiddenSenderInfo::HiddenSenderInfo(const QString &name, bool external)
 		? Ui::EmptyUserpic::ExternalName()
 		: name)) {
 	nameText.setText(st::msgNameStyle, name, Ui::NameTextOptions());
-	const auto parts = name.trimmed().split(' ', base::QStringSkipEmptyParts);
+	const auto parts = name.trimmed().split(' ', Qt::SkipEmptyParts);
 	firstName = parts[0];
 	for (const auto &part : parts.mid(1)) {
 		if (!lastName.isEmpty()) {

Telegram/SourceFiles/history/history_service.cpp

@@ -120,7 +120,7 @@ void HistoryService::setMessageByAction(const MTPmessageAction &action) {
 			result.text = tr::lng_action_add_user(tr::now, lt_from, fromLinkText(), lt_user, qsl("somebody"));
 		} else {
 			result.links.push_back(fromLink());
-			for (auto i = 0, l = users.size(); i != l; ++i) {
+			for (auto i = 0, l = int(users.size()); i != l; ++i) {
 				auto user = history()->owner().user(users[i].v);
 				result.links.push_back(user->createOpenLink());
 
@@ -641,7 +641,7 @@ HistoryService::PreparedText HistoryService::prepareInvitedToCallText(
 	} else if (users.isEmpty()) {
 		result.text = tr::lng_action_invite_user(tr::now, lt_from, fromLinkText(), lt_user, qsl("somebody"), lt_chat, chatText);
 	} else {
-		for (auto i = 0, l = users.size(); i != l; ++i) {
+		for (auto i = 0, l = int(users.size()); i != l; ++i) {
 			auto user = owner->user(users[i].v);
 			result.links.push_back(user->createOpenLink());
 

Telegram/SourceFiles/history/history_widget.cpp

@@ -168,7 +168,7 @@ const auto kPsaAboutPrefix = "cloud_lng_about_psa_";
 
 [[nodiscard]] crl::time CountToastDuration(const TextWithEntities &text) {
 	return std::clamp(
-		crl::time(1000) * text.text.size() / 14,
+		crl::time(1000) * int(text.text.size()) / 14,
 		crl::time(1000) * 5,
 		crl::time(1000) * 8);
 }
@@ -1653,7 +1653,7 @@ bool HistoryWidget::notify_switchInlineBotButtonReceived(const QString &query, U
 	if (samePeerBot) {
 		if (_history) {
 			TextWithTags textWithTags = { '@' + samePeerBot->username + ' ' + query, TextWithTags::Tags() };
-			MessageCursor cursor = { textWithTags.text.size(), textWithTags.text.size(), QFIXED_MAX };
+			MessageCursor cursor = { int(textWithTags.text.size()), int(textWithTags.text.size()), QFIXED_MAX };
 			_history->setLocalDraft(std::make_unique<Data::Draft>(
 				textWithTags,
 				0,
@@ -1674,7 +1674,7 @@ bool HistoryWidget::notify_switchInlineBotButtonReceived(const QString &query, U
 		using Section = Dialogs::EntryState::Section;
 
 		TextWithTags textWithTags = { '@' + bot->username + ' ' + query, TextWithTags::Tags() };
-		MessageCursor cursor = { textWithTags.text.size(), textWithTags.text.size(), QFIXED_MAX };
+		MessageCursor cursor = { int(textWithTags.text.size()), int(textWithTags.text.size()), QFIXED_MAX };
 		auto draft = std::make_unique<Data::Draft>(
 			textWithTags,
 			to.currentReplyToId,
@@ -6254,8 +6254,8 @@ void HistoryWidget::editMessage(not_null<HistoryItem*> item) {
 
 	const auto editData = PrepareEditText(item);
 	const auto cursor = MessageCursor {
-		editData.text.size(),
-		editData.text.size(),
+		int(editData.text.size()),
+		int(editData.text.size()),
 		QFIXED_MAX
 	};
 	const auto previewPage = [&]() -> WebPageData* {
@@ -6550,7 +6550,7 @@ void HistoryWidget::updatePreview() {
 				st::msgNameStyle,
 				tr::lng_preview_loading(tr::now),
 				Ui::NameTextOptions());
-			auto linkText = _previewLinks.splitRef(' ').at(0).toString();
+			auto linkText = QStringView(_previewLinks).split(' ').at(0).toString();
 			_previewDescription.setText(
 				st::messageTextStyle,
 				TextUtilities::Clean(linkText),

Telegram/SourceFiles/history/view/controls/history_view_compose_controls.cpp

@@ -2024,8 +2024,8 @@ void ComposeControls::editMessage(not_null<HistoryItem*> item) {
 	}
 	const auto editData = PrepareEditText(item);
 	const auto cursor = MessageCursor{
-		editData.text.size(),
-		editData.text.size(),
+		int(editData.text.size()),
+		int(editData.text.size()),
 		QFIXED_MAX
 	};
 	const auto previewPage = [&]() -> WebPageData* {
@@ -2164,7 +2164,7 @@ void ComposeControls::initWebpageProcess() {
 		if (ShowWebPagePreview(*previewData)) {
 			if (const auto till = (*previewData)->pendingTill) {
 				t = tr::lng_preview_loading(tr::now);
-				d = (*previewLinks).splitRef(' ').at(0).toString();
+				d = QStringView(*previewLinks).split(' ').at(0).toString();
 
 				const auto timeout = till - base::unixtime::now();
 				previewTimer->callOnce(

Telegram/SourceFiles/history/view/history_view_list_widget.cpp

@@ -2033,7 +2033,7 @@ void ListWidget::mouseReleaseEvent(QMouseEvent *e) {
 	}
 }
 
-void ListWidget::enterEventHook(QEvent *e) {
+void ListWidget::enterEventHook(QEnterEvent *e) {
 	mouseActionUpdate(QCursor::pos());
 	return TWidget::enterEventHook(e);
 }

Telegram/SourceFiles/history/view/history_view_list_widget.h

@@ -277,7 +277,7 @@ protected:
 	void mouseMoveEvent(QMouseEvent *e) override;
 	void mouseReleaseEvent(QMouseEvent *e) override;
 	void mouseDoubleClickEvent(QMouseEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 	void contextMenuEvent(QContextMenuEvent *e) override;
 

Telegram/SourceFiles/history/view/history_view_view_button.cpp

@@ -132,7 +132,6 @@ ViewButton::Inner::Inner(
 , link(std::make_shared<LambdaClickHandler>([=](ClickContext context) {
 	const auto my = context.other.value<ClickHandlerContext>();
 	if (const auto controller = my.sessionWindow.get()) {
-		const auto &data = controller->session().data();
 		const auto webpage = media->webpage();
 		if (!webpage) {
 			return;

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

@@ -89,7 +89,7 @@ void PaintWaveform(
 	const auto active = stm->msgWaveformActive;
 	const auto inactive = stm->msgWaveformInactive;
 	const auto wfSize = wf
-		? wf->size()
+		? int(wf->size())
 		: ::Media::Player::kWaveformSamplesCount;
 	const auto activeWidth = base::SafeRound(availableWidth * progress);
 

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

@@ -58,7 +58,7 @@ void Invoice::fillFromData(not_null<Data::Invoice*> invoice) {
 	statusText.entities.push_back({
 		EntityType::Bold,
 		0,
-		statusText.text.size() });
+		int(statusText.text.size()) });
 	statusText.text += ' ' + labelText().toUpper();
 	_status.setMarkedText(
 		st::defaultTextStyle,

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

@@ -24,10 +24,10 @@ namespace HistoryView {
 namespace {
 
 [[nodiscard]] TimeId TimeFromMatch(
-		const QStringRef &hours,
-		const QStringRef &minutes1,
-		const QStringRef &minutes2,
-		const QStringRef &seconds) {
+		QStringView hours,
+		QStringView minutes1,
+		QStringView minutes2,
+		QStringView seconds) {
 	auto ok1 = true;
 	auto ok2 = true;
 	auto ok3 = true;
@@ -71,10 +71,10 @@ TextWithEntities AddTimestampLinks(
 		offset = till;
 
 		const auto time = TimeFromMatch(
-			m.capturedRef(1),
-			m.capturedRef(2),
-			m.capturedRef(3),
-			m.capturedRef(4));
+			m.capturedView(1),
+			m.capturedView(2),
+			m.capturedView(3),
+			m.capturedView(4));
 		if (time < 0 || time > duration) {
 			continue;
 		}

Telegram/SourceFiles/info/media/info_media_list_widget.cpp

@@ -1906,7 +1906,7 @@ void ListWidget::validateTrippleClickStartTime() {
 	}
 }
 
-void ListWidget::enterEventHook(QEvent *e) {
+void ListWidget::enterEventHook(QEnterEvent *e) {
 	mouseActionUpdate(QCursor::pos());
 	return RpWidget::enterEventHook(e);
 }

Telegram/SourceFiles/info/media/info_media_list_widget.h

@@ -169,7 +169,7 @@ private:
 	void mouseReleaseEvent(QMouseEvent *e) override;
 	void mouseDoubleClickEvent(QMouseEvent *e) override;
 	void contextMenuEvent(QContextMenuEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 
 	void start();

Telegram/SourceFiles/inline_bots/inline_bot_layout_item.cpp

@@ -199,7 +199,7 @@ ClickHandlerPtr ItemBase::getResultPreviewHandler() const {
 }
 
 QString ItemBase::getResultThumbLetter() const {
-	auto parts = _result->_url.splitRef('/');
+	auto parts = QStringView(_result->_url).split('/');
 	if (!parts.isEmpty()) {
 		auto domain = parts.at(0);
 		if (parts.size() > 2 && domain.endsWith(':') && parts.at(1).isEmpty()) { // http:// and others

Telegram/SourceFiles/intro/intro_widget.cpp

@@ -44,6 +44,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "app.h"
 #include "styles/style_layers.h"
 #include "styles/style_intro.h"
+#include "base/qt_adapters.h"
 
 namespace Intro {
 namespace {
@@ -512,7 +513,8 @@ void Widget::resetAccount() {
 
 			const auto &type = error.type();
 			if (type.startsWith(qstr("2FA_CONFIRM_WAIT_"))) {
-				const auto seconds = type.midRef(
+				const auto seconds = base::StringViewMid(
+					type,
 					qstr("2FA_CONFIRM_WAIT_").size()).toInt();
 				const auto days = (seconds + 59) / 86400;
 				const auto hours = ((seconds + 59) % 86400) / 3600;

Telegram/SourceFiles/lang/lang_file_parser.cpp

@@ -174,7 +174,11 @@ QByteArray FileParser::ReadFile(const QString &absolutePath, const QString &rela
 
 	QByteArray data;
 	auto readUtf16Stream = [relativePath, absolutePath](auto &&stream) {
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+		stream.setEncoding(QStringConverter::Utf16);
+#else // Qt >= 6.0.0
 		stream.setCodec("UTF-16");
+#endif // Qt < 6.0.0
 		auto string = stream.readAll();
 		if (stream.status() != QTextStream::Ok) {
 			LOG(("Lang Error: Could not read UTF-16 data from '%1' ('%2')").arg(relativePath, absolutePath));

Telegram/SourceFiles/lang/lang_tag.cpp

@@ -9,6 +9,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 
 #include "lang/lang_keys.h"
 #include "ui/text/text.h"
+#include "base/qt_adapters.h"
 
 namespace Lang {
 namespace {
@@ -911,7 +912,7 @@ int NonZeroPartToInt(QString value) {
 		}
 	}
 	return (zeros > 0)
-		? (zeros < value.size() ? value.midRef(zeros).toInt() : 0)
+		? (zeros < value.size() ? base::StringViewMid(value, zeros).toInt() : 0)
 		: (value.isEmpty() ? 0 : value.toInt());
 }
 
@@ -1008,11 +1009,11 @@ QString ReplaceTag<QString>::Replace(QString &&original, const QString &replacem
 	auto result = QString();
 	result.reserve(original.size() + replacement.size() - kTagReplacementSize);
 	if (replacementPosition > 0) {
-		result.append(original.midRef(0, replacementPosition));
+		result.append(base::StringViewMid(original, 0, replacementPosition));
 	}
 	result.append(replacement);
 	if (replacementPosition + kTagReplacementSize < original.size()) {
-		result.append(original.midRef(replacementPosition + kTagReplacementSize));
+		result.append(base::StringViewMid(original, replacementPosition + kTagReplacementSize));
 	}
 	return result;
 }

Telegram/SourceFiles/lang/lang_text_entity.cpp

@@ -24,7 +24,7 @@ TextWithEntities ReplaceTag<TextWithEntities>::Call(TextWithEntities &&original,
 	if (originalEntitiesCount != 0 || replacementEntitiesCount != 0) {
 		result.entities.reserve(originalEntitiesCount + replacementEntitiesCount);
 
-		auto replacementEnd = replacementPosition + replacement.text.size();
+		auto replacementEnd = replacementPosition + int(replacement.text.size());
 		auto replacementEntity = replacement.entities.cbegin();
 		auto addReplacementEntitiesUntil = [&replacementEntity, &replacement, &result, replacementPosition, replacementEnd](int untilPosition) {
 			while (replacementEntity != replacement.entities.cend()) {
@@ -52,8 +52,8 @@ TextWithEntities ReplaceTag<TextWithEntities>::Call(TextWithEntities &&original,
 			if (end > replacementPosition) {
 				end = end + replacement.text.size() - kTagReplacementSize;
 			}
-			offset = std::clamp(offset, 0, result.text.size());
-			end = std::clamp(end, 0, result.text.size());
+			offset = std::clamp(offset, 0, int(result.text.size()));
+			end = std::clamp(end, 0, int(result.text.size()));
 
 			// Add all replacement entities that start before the current original entity.
 			addReplacementEntitiesUntil(offset);

Telegram/SourceFiles/logs.cpp

@@ -165,7 +165,7 @@ private:
 					QStringList oldlogs = working.entryList(QStringList("log_start*.txt"), QDir::Files);
 					for (QStringList::const_iterator i = oldlogs.cbegin(), e = oldlogs.cend(); i != e; ++i) {
 						QString oldlog = cWorkingDir() + *i, oldlogend = i->mid(qstr("log_start").size());
-						if (oldlogend.size() == 1 + qstr(".txt").size() && oldlogend.at(0).isDigit() && oldlogend.midRef(1) == qstr(".txt")) {
+						if (oldlogend.size() == 1 + qstr(".txt").size() && oldlogend.at(0).isDigit() && base::StringViewMid(oldlogend, 1) == qstr(".txt")) {
 							bool removed = QFile(oldlog).remove();
 							LOG(("Old start log '%1' found, deleted: %2").arg(*i, Logs::b(removed)));
 						}

Telegram/SourceFiles/mainwidget.cpp

@@ -531,8 +531,8 @@ bool MainWidget::shareUrl(
 		TextWithTags::Tags()
 	};
 	MessageCursor cursor = {
-		url.size() + 1,
-		url.size() + 1 + text.size(),
+		int(url.size()) + 1,
+		int(url.size()) + 1 + int(text.size()),
 		QFIXED_MAX
 	};
 	auto history = peer->owner().history(peer);
@@ -558,7 +558,7 @@ bool MainWidget::inlineSwitchChosen(PeerId peerId, const QString &botAndQuery) {
 	}
 	const auto h = peer->owner().history(peer);
 	TextWithTags textWithTags = { botAndQuery, TextWithTags::Tags() };
-	MessageCursor cursor = { botAndQuery.size(), botAndQuery.size(), QFIXED_MAX };
+	MessageCursor cursor = { int(botAndQuery.size()), int(botAndQuery.size()), QFIXED_MAX };
 	h->setLocalDraft(std::make_unique<Data::Draft>(
 		textWithTags,
 		0,

Telegram/SourceFiles/media/clip/media_clip_check_streaming.cpp

@@ -13,6 +13,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 
 #include <QtCore/QtEndian>
 #include <QtCore/QBuffer>
+#include <QtCore/QFile>
 
 namespace Media {
 namespace Clip {

Telegram/SourceFiles/media/clip/media_clip_ffmpeg.cpp

@@ -225,7 +225,7 @@ bool FFMpegReaderImplementation::renderFrame(QImage &to, bool &hasAlpha, const Q
 		}
 		// AV_NUM_DATA_POINTERS defined in AVFrame struct
 		uint8_t *toData[AV_NUM_DATA_POINTERS] = { to.bits(), nullptr };
-		int toLinesize[AV_NUM_DATA_POINTERS] = { to.bytesPerLine(), 0 };
+		int toLinesize[AV_NUM_DATA_POINTERS] = { int(to.bytesPerLine()), 0 };
 		sws_scale(_swsContext, _frame->data, _frame->linesize, 0, _frame->height, toData, toLinesize);
 	}
 	if (hasAlpha) {

Telegram/SourceFiles/media/clip/media_clip_implementation.h

@@ -8,6 +8,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #pragma once
 
 #include <QtCore/QBuffer>
+#include <QtCore/QFile>
 
 namespace Core {
 class FileLocation;

Telegram/SourceFiles/media/player/media_player_panel.cpp

@@ -164,7 +164,7 @@ void Panel::paintEvent(QPaintEvent *e) {
 	Ui::FillRoundRect(p, shadowedRect, st::menuBg, Ui::MenuCorners, nullptr, parts);
 }
 
-void Panel::enterEventHook(QEvent *e) {
+void Panel::enterEventHook(QEnterEvent *e) {
 	if (_ignoringEnterEvents || contentTooSmall()) return;
 
 	_hideTimer.cancel();

Telegram/SourceFiles/media/player/media_player_panel.h

@@ -44,7 +44,7 @@ public:
 protected:
 	void resizeEvent(QResizeEvent *e) override;
 	void paintEvent(QPaintEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 
 private:

Telegram/SourceFiles/media/player/media_player_volume_controller.cpp

@@ -149,7 +149,7 @@ void VolumeWidget::paintEvent(QPaintEvent *e) {
 	Ui::FillRoundRect(p, QRect(shadowedRect.x(), -st::roundRadiusSmall, shadowedRect.width(), shadowedRect.y() + shadowedRect.height() + st::roundRadiusSmall), st::menuBg, Ui::MenuCorners, nullptr, parts);
 }
 
-void VolumeWidget::enterEventHook(QEvent *e) {
+void VolumeWidget::enterEventHook(QEnterEvent *e) {
 	_hideTimer.stop();
 	if (_a_appearance.animating()) {
 		onShowStart();

Telegram/SourceFiles/media/player/media_player_volume_controller.h

@@ -59,7 +59,7 @@ public:
 protected:
 	void resizeEvent(QResizeEvent *e) override;
 	void paintEvent(QPaintEvent *e) override;
-	void enterEventHook(QEvent *e) override;
+	void enterEventHook(QEnterEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 
 	bool eventFilter(QObject *obj, QEvent *e) override;

Telegram/SourceFiles/media/streaming/media_streaming_utility.cpp

@@ -160,7 +160,7 @@ QImage ConvertFrame(
 
 		// AV_NUM_DATA_POINTERS defined in AVFrame struct
 		uint8_t *data[AV_NUM_DATA_POINTERS] = { storage.bits(), nullptr };
-		int linesize[AV_NUM_DATA_POINTERS] = { storage.bytesPerLine(), 0 };
+		int linesize[AV_NUM_DATA_POINTERS] = { int(storage.bytesPerLine()), 0 };
 
 		sws_scale(
 			stream.swscale.get(),

Telegram/SourceFiles/media/streaming/media_streaming_video_track.cpp

@@ -55,7 +55,7 @@ static_assert(kDisplaySkipped != kTimeUnknown);
 		0,
 	};
 	uint8_t *dstData[AV_NUM_DATA_POINTERS] = { result.bits(), nullptr };
-	int dstLinesize[AV_NUM_DATA_POINTERS] = { result.bytesPerLine(), 0 };
+	int dstLinesize[AV_NUM_DATA_POINTERS] = { int(result.bytesPerLine()), 0 };
 
 	sws_scale(
 		swscale.get(),

Telegram/SourceFiles/media/view/media_view_overlay_opengl.h

@@ -11,7 +11,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "ui/gl/gl_image.h"
 #include "ui/gl/gl_primitives.h"
 
-#include <QtGui/QOpenGLBuffer>
+#include <QOpenGLBuffer>
 
 namespace Media::View {
 

Telegram/SourceFiles/media/view/media_view_overlay_widget.cpp

@@ -74,13 +74,13 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "facades.h"
 #include "styles/style_media_view.h"
 #include "styles/style_chat.h"
+#include "base/qt_adapters.h"
 
 #ifdef Q_OS_MAC
 #include "platform/mac/touchbar/mac_touchbar_media_view.h"
 #endif // Q_OS_MAC
 
 #include <QtWidgets/QApplication>
-#include <QtWidgets/QDesktopWidget>
 #include <QtCore/QBuffer>
 #include <QtGui/QGuiApplication>
 #include <QtGui/QClipboard>
@@ -4430,7 +4430,7 @@ bool OverlayWidget::handleContextMenu(std::optional<QPoint> position) {
 }
 
 bool OverlayWidget::handleTouchEvent(not_null<QTouchEvent*> e) {
-	if (e->device()->type() != QTouchDevice::TouchScreen) {
+	if (e->device()->type() != base::TouchDevice::TouchScreen) {
 		return false;
 	} else if (e->type() == QEvent::TouchBegin
 		&& !e->touchPoints().isEmpty()

Telegram/SourceFiles/media/view/media_view_pip.cpp

@@ -33,7 +33,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_widgets.h"
 #include "styles/style_window.h"
 #include "styles/style_media_view.h"
-#include "base/qt_adapters.h"
 
 #include <QtGui/QWindow>
 #include <QtGui/QScreen>
@@ -51,7 +50,7 @@ constexpr auto kMsInSecond = 1000;
 }
 
 [[nodiscard]] QRect ScreenFromPosition(QPoint point) {
-	const auto screen = base::QScreenNearestTo(point);
+	const auto screen = QGuiApplication::screenAt(point);
 	const auto use = screen ? screen : QGuiApplication::primaryScreen();
 	return use
 		? use->availableGeometry()

Telegram/SourceFiles/media/view/media_view_pip_opengl.h

@@ -11,7 +11,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "ui/gl/gl_image.h"
 #include "ui/gl/gl_primitives.h"
 
-#include <QtGui/QOpenGLBuffer>
+#include <QOpenGLBuffer>
 
 namespace Media::View {
 

Telegram/SourceFiles/mtproto/details/mtproto_dc_key_binder.cpp

@@ -107,7 +107,7 @@ SerializedRequest DcKeyBinder::prepareRequest(
 DcKeyBindState DcKeyBinder::handleResponse(const mtpBuffer &response) {
 	Expects(!response.isEmpty());
 
-	auto from = response.begin();
+	auto from = response.data();
 	const auto end = from + response.size();
 	auto error = MTPRpcError();
 	if (response[0] == mtpc_boolTrue) {

Telegram/SourceFiles/mtproto/details/mtproto_tls_socket.cpp

@@ -710,7 +710,7 @@ int64 TlsSocket::read(bytes::span buffer) {
 	while (_incomingGoodDataLimit) {
 		const auto available = std::min(
 			_incomingGoodDataLimit,
-			_incoming.size() - _incomingGoodDataOffset);
+			int(_incoming.size()) - _incomingGoodDataOffset);
 		if (available <= 0) {
 			return written;
 		}

Telegram/SourceFiles/mtproto/mtproto_dc_options.cpp

@@ -11,7 +11,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "mtproto/facade.h"
 #include "mtproto/connection_tcp.h"
 #include "storage/serialize_common.h"
-#include "base/qt_adapters.h"
 
 #include <QtCore/QFile>
 #include <QtCore/QRegularExpression>
@@ -754,10 +753,12 @@ bool DcOptions::loadFromFile(const QString &path) {
 		return false;
 	}
 	QTextStream stream(&f);
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 	stream.setCodec("UTF-8");
+#endif // Qt < 6.0.0
 	while (!stream.atEnd()) {
 		auto line = stream.readLine();
-		auto components = line.split(QRegularExpression(R"(\s)"), base::QStringSkipEmptyParts);
+		auto components = line.split(QRegularExpression(R"(\s)"), Qt::SkipEmptyParts);
 		if (components.isEmpty() || components[0].startsWith('#')) {
 			continue;
 		}
@@ -816,7 +817,9 @@ bool DcOptions::writeToFile(const QString &path) const {
 		return false;
 	}
 	QTextStream stream(&f);
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 	stream.setCodec("UTF-8");
+#endif // Qt < 6.0.0
 
 	ReadLocker lock(this);
 	for (const auto &item : _data) {