all: refactor windows code out of core

There are still some links from core to window but its now separate
enough to fix PanelWindow in qml tooling.

src/window/proxywindow.hpp

@@ -0,0 +1,152 @@
+#pragma once
+
+#include <qcolor.h>
+#include <qcontainerfwd.h>
+#include <qevent.h>
+#include <qnamespace.h>
+#include <qobject.h>
+#include <qqmllist.h>
+#include <qqmlparserstatus.h>
+#include <qquickitem.h>
+#include <qquickwindow.h>
+#include <qtmetamacros.h>
+#include <qtypes.h>
+
+#include "../core/qmlscreen.hpp"
+#include "../core/region.hpp"
+#include "../core/reload.hpp"
+#include "windowinterface.hpp"
+
+// Proxy to an actual window exposing a limited property set with the ability to
+// transfer it to a new window.
+
+///! Base class for reloadable windows
+///
+/// [ShellWindow]: ../shellwindow
+/// [FloatingWindow]: ../floatingwindow
+class ProxyWindowBase: public Reloadable {
+	Q_OBJECT;
+	/// The QtQuick window backing this window.
+	///
+	/// > [!WARNING] Do not expect values set via this property to work correctly.
+	/// > Values set this way will almost certainly misbehave across a reload, possibly
+	/// > even without one.
+	/// >
+	/// > Use **only** if you know what you are doing.
+	Q_PROPERTY(QQuickWindow* _backingWindow READ backingWindow);
+	Q_PROPERTY(QQuickItem* contentItem READ contentItem CONSTANT);
+	Q_PROPERTY(bool visible READ isVisible WRITE setVisible NOTIFY visibleChanged);
+	Q_PROPERTY(qint32 width READ width WRITE setWidth NOTIFY widthChanged);
+	Q_PROPERTY(qint32 height READ height WRITE setHeight NOTIFY heightChanged);
+	Q_PROPERTY(QuickshellScreenInfo* screen READ screen WRITE setScreen NOTIFY screenChanged);
+	Q_PROPERTY(QColor color READ color WRITE setColor NOTIFY colorChanged);
+	Q_PROPERTY(PendingRegion* mask READ mask WRITE setMask NOTIFY maskChanged);
+	Q_PROPERTY(QObject* windowTransform READ windowTransform NOTIFY windowTransformChanged);
+	Q_PROPERTY(bool backingWindowVisible READ isVisibleDirect NOTIFY backerVisibilityChanged);
+	Q_PROPERTY(QQmlListProperty<QObject> data READ data);
+	Q_CLASSINFO("DefaultProperty", "data");
+
+public:
+	explicit ProxyWindowBase(QObject* parent = nullptr);
+	~ProxyWindowBase() override;
+
+	ProxyWindowBase(ProxyWindowBase&) = delete;
+	ProxyWindowBase(ProxyWindowBase&&) = delete;
+	void operator=(ProxyWindowBase&) = delete;
+	void operator=(ProxyWindowBase&&) = delete;
+
+	void onReload(QObject* oldInstance) override;
+	void createWindow();
+	void deleteWindow();
+
+	// Disown the backing window and delete all its children.
+	virtual QQuickWindow* disownWindow();
+
+	virtual QQuickWindow* retrieveWindow(QObject* oldInstance);
+	virtual QQuickWindow* createQQuickWindow();
+	virtual void connectWindow();
+	virtual void completeWindow();
+	virtual void postCompleteWindow();
+	[[nodiscard]] virtual bool deleteOnInvisible() const;
+
+	[[nodiscard]] QQuickWindow* backingWindow() const;
+	[[nodiscard]] QQuickItem* contentItem() const;
+
+	[[nodiscard]] virtual bool isVisible() const;
+	[[nodiscard]] virtual bool isVisibleDirect() const;
+	virtual void setVisible(bool visible);
+	virtual void setVisibleDirect(bool visible);
+
+	[[nodiscard]] virtual qint32 x() const;
+	[[nodiscard]] virtual qint32 y() const;
+
+	[[nodiscard]] virtual qint32 width() const;
+	virtual void setWidth(qint32 width);
+
+	[[nodiscard]] virtual qint32 height() const;
+	virtual void setHeight(qint32 height);
+
+	[[nodiscard]] virtual QuickshellScreenInfo* screen() const;
+	virtual void setScreen(QuickshellScreenInfo* screen);
+
+	[[nodiscard]] QColor color() const;
+	virtual void setColor(QColor color);
+
+	[[nodiscard]] PendingRegion* mask() const;
+	virtual void setMask(PendingRegion* mask);
+
+	[[nodiscard]] QObject* windowTransform() const { return nullptr; } // NOLINT
+
+	[[nodiscard]] QQmlListProperty<QObject> data();
+
+signals:
+	void windowConnected();
+	void windowDestroyed();
+	void visibleChanged();
+	void backerVisibilityChanged();
+	void xChanged();
+	void yChanged();
+	void widthChanged();
+	void heightChanged();
+	void windowTransformChanged();
+	void screenChanged();
+	void colorChanged();
+	void maskChanged();
+
+protected slots:
+	virtual void onWidthChanged();
+	virtual void onHeightChanged();
+	void onMaskChanged();
+	void onMaskDestroyed();
+	void onScreenDestroyed();
+
+protected:
+	bool mVisible = true;
+	qint32 mWidth = 100;
+	qint32 mHeight = 100;
+	QScreen* mScreen = nullptr;
+	QColor mColor = Qt::white;
+	PendingRegion* mMask = nullptr;
+	QQuickWindow* window = nullptr;
+	QQuickItem* mContentItem = nullptr;
+	bool reloadComplete = false;
+
+private:
+	void polishItems();
+	void updateMask();
+};
+
+class ProxyWindowAttached: public QsWindowAttached {
+	Q_OBJECT;
+
+public:
+	explicit ProxyWindowAttached(ProxyWindowBase* window)
+	    : QsWindowAttached(window)
+	    , mWindow(window) {}
+
+	[[nodiscard]] QObject* window() const override;
+	[[nodiscard]] QQuickItem* contentItem() const override;
+
+private:
+	ProxyWindowBase* mWindow;
+};