Revert "Simplify Windows native event filter."

With that commit the window frame on Windows 7 is still bugged :(

ui/platform/ui_platform_window.cpp

@@ -70,13 +70,6 @@ rpl::producer<HitTestResult> BasicWindowHelper::systemButtonDown() const {
 	return rpl::never<HitTestResult>();
 }
 
-bool BasicWindowHelper::nativeEvent(
-		const QByteArray &eventType,
-		void *message,
-		base::NativeEventResult *result) {
-	return false;
-}
-
 void BasicWindowHelper::setTitle(const QString &title) {
 	_window->setWindowTitle(title);
 }

ui/platform/ui_platform_window.h

@@ -8,7 +8,6 @@
 
 #include "base/flags.h"
 #include "base/object_ptr.h"
-#include "base/qt/qt_common_adapters.h"
 #include "ui/round_rect.h"
 
 namespace style {
@@ -49,10 +48,6 @@ public:
 		-> rpl::producer<HitTestResult>;
 	[[nodiscard]] virtual auto systemButtonDown() const
 		-> rpl::producer<HitTestResult>;
-	[[nodiscard]] virtual bool nativeEvent(
-		const QByteArray &eventType,
-		void *message,
-		base::NativeEventResult *result);
 	virtual void setTitle(const QString &title);
 	virtual void setTitleStyle(const style::WindowTitle &st);
 	virtual void setNativeFrame(bool enabled);

ui/platform/win/ui_window_win.cpp

@@ -17,6 +17,7 @@
 #include "styles/palette.h"
 #include "styles/style_widgets.h"
 
+#include <QtCore/QAbstractNativeEventFilter>
 #include <QtGui/QWindow>
 #include <QtWidgets/QStyleFactory>
 #include <QtWidgets/QApplication>
@@ -128,6 +129,50 @@ void FixAeroSnap(HWND handle) {
 
 } // namespace
 
+class WindowHelper::NativeFilter final : public QAbstractNativeEventFilter {
+public:
+       void registerWindow(HWND handle, not_null<WindowHelper*> helper);
+       void unregisterWindow(HWND handle);
+
+       bool nativeEventFilter(
+               const QByteArray &eventType,
+               void *message,
+               long *result) override;
+
+private:
+       base::flat_map<HWND, not_null<WindowHelper*>> _windowByHandle;
+
+};
+
+void WindowHelper::NativeFilter::registerWindow(
+               HWND handle,
+               not_null<WindowHelper*> helper) {
+       _windowByHandle.emplace(handle, helper);
+}
+
+void WindowHelper::NativeFilter::unregisterWindow(HWND handle) {
+       _windowByHandle.remove(handle);
+}
+
+bool WindowHelper::NativeFilter::nativeEventFilter(
+               const QByteArray &eventType,
+               void *message,
+               long *result) {
+       auto filtered = false;
+       const auto msg = static_cast<MSG*>(message);
+       const auto i = _windowByHandle.find(msg->hwnd);
+       if (i != end(_windowByHandle)) {
+               base::Integration::Instance().enterFromEventLoop([&] {
+                       filtered = i->second->handleNativeEvent(
+                               msg->message,
+                               msg->wParam,
+                               msg->lParam,
+                               reinterpret_cast<LRESULT*>(result));
+               });
+       }
+       return filtered;
+}
+
 WindowHelper::WindowHelper(not_null<RpWidget*> window)
 : BasicWindowHelper(window)
 , _handle(ResolveWindowHandle(window))
@@ -141,6 +186,7 @@ WindowHelper::WindowHelper(not_null<RpWidget*> window)
 }
 
 WindowHelper::~WindowHelper() {
+	GetNativeFilter()->unregisterWindow(_handle);
 }
 
 void WindowHelper::initInWindow(not_null<RpWindow*> window) {
@@ -272,6 +318,7 @@ rpl::producer<HitTestResult> WindowHelper::systemButtonDown() const {
 
 void WindowHelper::init() {
 	_title->show();
+	GetNativeFilter()->registerWindow(_handle, this);
 
 	style::PaletteChanged(
 	) | rpl::start_with_next([=] {
@@ -321,26 +368,6 @@ void WindowHelper::init() {
 	initialShadowUpdate();
 }
 
-bool WindowHelper::nativeEvent(
-		const QByteArray &eventType,
-		void *message,
-		base::NativeEventResult *result) {
-	const auto msg = static_cast<MSG*>(message);
-	auto lresult = LRESULT(*result);
-	const auto guard = gsl::finally([&] {
-		*result = base::NativeEventResult(lresult);
-	});
-	auto filtered = false;
-	base::Integration::Instance().enterFromEventLoop([&] {
-		filtered = handleNativeEvent(
-			msg->message,
-			msg->wParam,
-			msg->lParam,
-			&lresult);
-	});
-	return filtered;
-}
-
 bool WindowHelper::handleNativeEvent(
 		UINT msg,
 		WPARAM wParam,
@@ -762,6 +789,18 @@ void WindowHelper::fixMaximizedWindow() {
 	}
 }
 
+not_null<WindowHelper::NativeFilter*> WindowHelper::GetNativeFilter() {
+       Expects(QCoreApplication::instance() != nullptr);
+
+       static const auto GlobalFilter = [&] {
+               const auto application = QCoreApplication::instance();
+               const auto filter = Ui::CreateChild<NativeFilter>(application);
+               application->installNativeEventFilter(filter);
+               return filter;
+       }();
+       return GlobalFilter;
+}
+
 HWND GetWindowHandle(not_null<QWidget*> widget) {
 	const auto toplevel = widget->window();
 	toplevel->createWinId();

ui/platform/win/ui_window_win.h

@@ -44,12 +44,10 @@ public:
 	[[nodiscard]] auto systemButtonDown() const
 		-> rpl::producer<HitTestResult> override;
 
-	[[nodiscard]] bool nativeEvent(
-		const QByteArray &eventType,
-		void *message,
-		base::NativeEventResult *result) override;
-
 private:
+	class NativeFilter;
+	friend class NativeFilter;
+
 	void init();
 	void updateMargins();
 	void updateWindowFrameColors();
@@ -72,6 +70,7 @@ private:
 	[[nodiscard]] HitTestResult systemButtonHitTest(int result) const;
 
 	[[nodiscard]] int titleHeight() const;
+	static not_null<NativeFilter*> GetNativeFilter();
 
 	const HWND _handle = nullptr;
 	const not_null<TitleWidget*> _title;

ui/widgets/rp_window.cpp

@@ -17,8 +17,6 @@ RpWindow::RpWindow(QWidget *parent)
 
 	_helper->initInWindow(this);
 	hide();
-
-	_initialized = true;
 }
 
 RpWindow::~RpWindow() = default;
@@ -101,17 +99,4 @@ void RpWindow::setBodyTitleArea(
 	_helper->setBodyTitleArea(std::move(testMethod));
 }
 
-bool RpWindow::nativeEvent(
-		const QByteArray &eventType,
-		void *message,
-		base::NativeEventResult *result) {
-	if (_initialized && _helper->nativeEvent(
-		eventType,
-		message,
-		result)) {
-		return true;
-	}
-	return RpWidget::nativeEvent(eventType, message, result);
-}
-
 } // namespace Ui

ui/widgets/rp_window.h

@@ -8,7 +8,6 @@
 
 #include "ui/rp_widget.h"
 #include "base/flags.h"
-#include "base/qt/qt_common_adapters.h"
 
 namespace style {
 struct WindowTitle;
@@ -68,14 +67,7 @@ public:
 	void close();
 	void setBodyTitleArea(Fn<WindowTitleHitTestFlags(QPoint)> testMethod);
 
-protected:
-	bool nativeEvent(
-		const QByteArray &eventType,
-		void *message,
-		base::NativeEventResult *result) override;
-
 private:
-	bool _initialized = false;
 	const std::unique_ptr<Platform::BasicWindowHelper> _helper;
 
 };