wayland/layershell: refactor layer shell surface integration

In addition to the much needed cleanup:

- The bridge/extension type is now directly tied to the QWindow
instead of the WlrLayershell object, and is much smaller.
- Layer requests are now comitted via polish instead of for each
change individually.

src/wayland/wlr_layershell/surface.hpp

@@ -2,6 +2,8 @@
 
 #include <private/qwaylandshellsurface_p.h>
 #include <private/qwaylandwindow_p.h>
+#include <qobject.h>
+#include <qsize.h>
 #include <qtclasshelpermacros.h>
 #include <qtwaylandclientexports.h>
 #include <qtypes.h>
@@ -9,40 +11,76 @@
 #include <qwindow.h>
 
 #include "shell_integration.hpp"
-#include "window.hpp"
+#include "wlr_layershell.hpp"
 
-class QSWaylandLayerSurface
+namespace qs::wayland::layershell {
+
+struct LayerSurfaceState {
+	QSize implicitSize;
+	Anchors anchors;
+	Margins margins;
+	WlrLayer::Enum layer = WlrLayer::Top;
+	qint32 exclusiveZone = 0;
+	WlrKeyboardFocus::Enum keyboardFocus = WlrKeyboardFocus::None;
+
+	bool compositorPickesScreen = true;
+	QString mNamespace = "quickshell";
+
+	[[nodiscard]] bool isCompatible(const LayerSurfaceState& other) const {
+		return other.mNamespace == this->mNamespace;
+	}
+};
+
+class LayerSurface;
+
+class LayerSurfaceBridge: public QObject {
+public:
+	LayerSurfaceState state;
+
+	void commitState();
+
+	// Returns a bridge if attached, otherwise nullptr.
+	static LayerSurfaceBridge* get(QWindow* window);
+
+	// Creates or reuses a bridge on the given window and returns if it compatible, otherwise nullptr.
+	static LayerSurfaceBridge* init(QWindow* window, LayerSurfaceState state);
+
+private:
+	explicit LayerSurfaceBridge(QWindow* parent): QObject(parent) {}
+
+	LayerSurface* surface = nullptr;
+
+	friend class LayerSurface;
+};
+
+class LayerSurface
     : public QtWaylandClient::QWaylandShellSurface
     , public QtWayland::zwlr_layer_surface_v1 {
 public:
-	QSWaylandLayerSurface(
-	    QSWaylandLayerShellIntegration* shell,
-	    QtWaylandClient::QWaylandWindow* window
-	);
+	LayerSurface(LayerShellIntegration* shell, QtWaylandClient::QWaylandWindow* window);
 
-	~QSWaylandLayerSurface() override;
-	Q_DISABLE_COPY_MOVE(QSWaylandLayerSurface);
+	~LayerSurface() override;
+	Q_DISABLE_COPY_MOVE(LayerSurface);
 
 	[[nodiscard]] bool isExposed() const override;
 	void applyConfigure() override;
-	void setWindowGeometry(const QRect& geometry) override;
+	void setWindowGeometry(const QRect& /*geometry*/) override {}
 
 	void attachPopup(QtWaylandClient::QWaylandShellSurface* popup) override;
 
+	void commit();
+
 private:
 	void zwlr_layer_surface_v1_configure(quint32 serial, quint32 width, quint32 height) override;
 	void zwlr_layer_surface_v1_closed() override;
 
 	QWindow* qwindow();
-	void updateLayer();
-	void updateAnchors();
-	void updateMargins();
-	void updateExclusiveZone();
-	void updateKeyboardFocus();
 
-	LayershellWindowExtension* ext;
-	QSize size;
+	LayerSurfaceBridge* bridge;
 	bool configured = false;
+	QSize size;
 
-	friend class LayershellWindowExtension;
+	LayerSurfaceState committed;
 };
+
+} // namespace qs::wayland::layershell