Add notification observer on Mac

SineStriker

2023-12-27 88b5b56b6a67d93208eae3980af2f30da09dd8ae

 src/core/contexts/cocoawindowcontext.mm

@@ -3,106 +3,148 @@
#include <objc/runtime.h>
#include <AppKit/AppKit.h>

#include <Cocoa/Cocoa.h>

#include <QtGui/QGuiApplication>

#include "qwkglobal_p.h"
#include "systemwindow_p.h"

namespace QWK {

#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
    static const struct QWK_Hook {
        QWK_Hook() {
            qputenv("QT_MAC_WANTS_LAYER", "1");
        }
    } g_hook{};
#endif
    struct NSWindowProxy;

    class NSWindowProxy : public QObject {
        Q_OBJECT
    public:
    using ProxyList = QHash<WId, NSWindowProxy *>;
    Q_GLOBAL_STATIC(ProxyList, g_proxyList);

    using ProxyList2 = QHash<NSWindow *, NSWindowProxy *>;
    Q_GLOBAL_STATIC(ProxyList2, g_proxyIndexes);

}

struct QWK_NSWindowDelegate {
public:
    virtual ~QWK_NSWindowDelegate() = default;
    virtual void windowWillEnterFullScreen(){};
    virtual void windowDidEnterFullScreen(){};
    virtual void windowWillExitFullScreen(){};
    virtual void windowDidExitFullScreen(){};
    virtual void windowDidResize(){};
};

//
// Objective C++ Begin
//

@interface QWK_NSWindowObserver : NSObject {
}
@end

@implementation QWK_NSWindowObserver

- (id)init {
    self = [super init];
    if (self) {
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(windowWillEnterFullScreen:)
                                                     name:NSWindowWillEnterFullScreenNotification
                                                   object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(windowDidEnterFullScreen:)
                                                     name:NSWindowDidEnterFullScreenNotification
                                                   object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(windowWillExitFullScreen:)
                                                     name:NSWindowWillExitFullScreenNotification
                                                   object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(windowDidExitFullScreen:)
                                                     name:NSWindowDidExitFullScreenNotification
                                                   object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(windowDidResize:)
                                                     name:NSWindowDidResizeNotification
                                                   object:nil];
    }
    return self;
}

- (void)dealloc {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    [super dealloc];
}

- (void)windowWillEnterFullScreen:(NSNotification *)notification {
    auto nswindow = reinterpret_cast<NSWindow *>(notification.object);
    if (auto proxy = QWK::g_proxyIndexes->value(nswindow)) {
        reinterpret_cast<QWK_NSWindowDelegate *>(proxy)->windowWillEnterFullScreen();
    }
}

- (void)windowDidEnterFullScreen:(NSNotification *)notification {
    auto nswindow = reinterpret_cast<NSWindow *>(notification.object);
    if (auto proxy = QWK::g_proxyIndexes->value(nswindow)) {
        reinterpret_cast<QWK_NSWindowDelegate *>(proxy)->windowDidEnterFullScreen();
    }
}

- (void)windowWillExitFullScreen:(NSNotification *)notification {
    auto nswindow = reinterpret_cast<NSWindow *>(notification.object);
    if (auto proxy = QWK::g_proxyIndexes->value(nswindow)) {
        reinterpret_cast<QWK_NSWindowDelegate *>(proxy)->windowWillExitFullScreen();
    }
}

- (void)windowDidExitFullScreen:(NSNotification *)notification {
    auto nswindow = reinterpret_cast<NSWindow *>(notification.object);
    if (auto proxy = QWK::g_proxyIndexes->value(nswindow)) {
        reinterpret_cast<QWK_NSWindowDelegate *>(proxy)->windowDidExitFullScreen();
    }
}

- (void)windowDidResize:(NSNotification *)notification {
    auto nswindow = reinterpret_cast<NSWindow *>(notification.object);
    if (auto proxy = QWK::g_proxyIndexes->value(nswindow)) {
        reinterpret_cast<QWK_NSWindowDelegate *>(proxy)->windowDidResize();
    }
}

@end

//
// Objective C++ End
//

namespace QWK {

    struct NSWindowProxy : public QWK_NSWindowDelegate {
        NSWindowProxy(NSWindow *macWindow) {
            if (instances.contains(macWindow)) {
                return;
            }
            nswindow = macWindow;
            instances.insert(macWindow, this);
            if (!windowClass) {
                windowClass = [nswindow class];
                replaceImplementations();
            }
            g_proxyIndexes->insert(nswindow, this);
        }

        ~NSWindowProxy() override {
            instances.remove(nswindow);
            if (instances.count() <= 0) {
                restoreImplementations();
                windowClass = nil;
            }
            nswindow = nil;
            g_proxyIndexes->remove(nswindow);
        }

    public Q_SLOTS:
        void replaceImplementations() {
            Method method = class_getInstanceMethod(windowClass, @selector(setStyleMask:));
            Q_ASSERT(method);
            oldSetStyleMask = reinterpret_cast<setStyleMaskPtr>(
                method_setImplementation(method, reinterpret_cast<IMP>(setStyleMask)));
            Q_ASSERT(oldSetStyleMask);

            method =
                class_getInstanceMethod(windowClass, @selector(setTitlebarAppearsTransparent:));
            Q_ASSERT(method);
            oldSetTitlebarAppearsTransparent =
                reinterpret_cast<setTitlebarAppearsTransparentPtr>(method_setImplementation(
                    method, reinterpret_cast<IMP>(setTitlebarAppearsTransparent)));
            Q_ASSERT(oldSetTitlebarAppearsTransparent);

#if 0
        method = class_getInstanceMethod(windowClass, @selector(canBecomeKeyWindow));
        Q_ASSERT(method);
        oldCanBecomeKeyWindow = reinterpret_cast<canBecomeKeyWindowPtr>(method_setImplementation(method, reinterpret_cast<IMP>(canBecomeKeyWindow)));
        Q_ASSERT(oldCanBecomeKeyWindow);

        method = class_getInstanceMethod(windowClass, @selector(canBecomeMainWindow));
        Q_ASSERT(method);
        oldCanBecomeMainWindow = reinterpret_cast<canBecomeMainWindowPtr>(method_setImplementation(method, reinterpret_cast<IMP>(canBecomeMainWindow)));
        Q_ASSERT(oldCanBecomeMainWindow);
#endif

            method = class_getInstanceMethod(windowClass, @selector(sendEvent:));
            Q_ASSERT(method);
            oldSendEvent = reinterpret_cast<sendEventPtr>(
                method_setImplementation(method, reinterpret_cast<IMP>(sendEvent)));
            Q_ASSERT(oldSendEvent);
        void windowWillEnterFullScreen() override {
            qDebug() << "windowWillEnterFullScreen";
        }

        void restoreImplementations() {
            Method method = class_getInstanceMethod(windowClass, @selector(setStyleMask:));
            Q_ASSERT(method);
            method_setImplementation(method, reinterpret_cast<IMP>(oldSetStyleMask));
            oldSetStyleMask = nil;
        void windowDidEnterFullScreen() override {
            qDebug() << "windowDidEnterFullScreen";
        }

            method =
                class_getInstanceMethod(windowClass, @selector(setTitlebarAppearsTransparent:));
            Q_ASSERT(method);
            method_setImplementation(method,
                                     reinterpret_cast<IMP>(oldSetTitlebarAppearsTransparent));
            oldSetTitlebarAppearsTransparent = nil;
        void windowWillExitFullScreen() override {
            qDebug() << "windowWillExitFullScreen";
        }

#if 0
        method = class_getInstanceMethod(windowClass, @selector(canBecomeKeyWindow));
        Q_ASSERT(method);
        method_setImplementation(method, reinterpret_cast<IMP>(oldCanBecomeKeyWindow));
        oldCanBecomeKeyWindow = nil;
        void windowDidExitFullScreen() override {
            qDebug() << "windowDidExitFullScreen";
        }

        method = class_getInstanceMethod(windowClass, @selector(canBecomeMainWindow));
        Q_ASSERT(method);
        method_setImplementation(method, reinterpret_cast<IMP>(oldCanBecomeMainWindow));
        oldCanBecomeMainWindow = nil;
#endif

            method = class_getInstanceMethod(windowClass, @selector(sendEvent:));
            Q_ASSERT(method);
            method_setImplementation(method, reinterpret_cast<IMP>(oldSendEvent));
            oldSendEvent = nil;
        void windowDidResize() override {
            qDebug() << "windowDidResize";
        }

        void setSystemTitleBarVisible(const bool visible) {
@@ -110,6 +152,7 @@
            if (!nsview) {
                return;
            }

            nsview.wantsLayer = YES;
            nswindow.styleMask |= NSWindowStyleMaskResizable;
            if (visible) {
@@ -122,9 +165,10 @@
            nswindow.hasShadow = YES;
            nswindow.showsToolbarButton = NO;
            nswindow.movableByWindowBackground = NO;
            nswindow.movable = NO;
            // For some unknown reason, we don't need the following hack in Qt versions below or
            // equal to 6.2.4.
            nswindow.movable = NO; // This line causes the window in the wrong position when
                                   // become fullscreen.
            //  For some unknown reason, we don't need the following hack in Qt versions below or
            //  equal to 6.2.4.
#if (QT_VERSION > QT_VERSION_CHECK(6, 2, 4))
            [nswindow standardWindowButton:NSWindowCloseButton].hidden = (visible ? NO : YES);
            [nswindow standardWindowButton:NSWindowMiniaturizeButton].hidden = (visible ? NO : YES);
@@ -132,9 +176,66 @@
#endif
        }

        static void replaceImplementations() {
            Method method = class_getInstanceMethod(windowClass, @selector(setStyleMask:));
            oldSetStyleMask = reinterpret_cast<setStyleMaskPtr>(
                method_setImplementation(method, reinterpret_cast<IMP>(setStyleMask)));

            method =
                class_getInstanceMethod(windowClass, @selector(setTitlebarAppearsTransparent:));
            oldSetTitlebarAppearsTransparent =
                reinterpret_cast<setTitlebarAppearsTransparentPtr>(method_setImplementation(
                    method, reinterpret_cast<IMP>(setTitlebarAppearsTransparent)));

#if 0
            method = class_getInstanceMethod(windowClass, @selector(canBecomeKeyWindow));
            oldCanBecomeKeyWindow = reinterpret_cast<canBecomeKeyWindowPtr>(method_setImplementation(method, reinterpret_cast<IMP>(canBecomeKeyWindow)));

            method = class_getInstanceMethod(windowClass, @selector(canBecomeMainWindow));
            oldCanBecomeMainWindow = reinterpret_cast<canBecomeMainWindowPtr>(method_setImplementation(method, reinterpret_cast<IMP>(canBecomeMainWindow)));
#endif

            method = class_getInstanceMethod(windowClass, @selector(sendEvent:));
            oldSendEvent = reinterpret_cast<sendEventPtr>(
                method_setImplementation(method, reinterpret_cast<IMP>(sendEvent)));

            // Alloc
            windowObserver = [[QWK_NSWindowObserver alloc] init];
        }

        static void restoreImplementations() {
            Method method = class_getInstanceMethod(windowClass, @selector(setStyleMask:));
            method_setImplementation(method, reinterpret_cast<IMP>(oldSetStyleMask));
            oldSetStyleMask = nil;

            method =
                class_getInstanceMethod(windowClass, @selector(setTitlebarAppearsTransparent:));
            method_setImplementation(method,
                                     reinterpret_cast<IMP>(oldSetTitlebarAppearsTransparent));
            oldSetTitlebarAppearsTransparent = nil;

#if 0
            method = class_getInstanceMethod(windowClass, @selector(canBecomeKeyWindow));
            method_setImplementation(method, reinterpret_cast<IMP>(oldCanBecomeKeyWindow));
            oldCanBecomeKeyWindow = nil;

            method = class_getInstanceMethod(windowClass, @selector(canBecomeMainWindow));
            method_setImplementation(method, reinterpret_cast<IMP>(oldCanBecomeMainWindow));
            oldCanBecomeMainWindow = nil;
#endif

            method = class_getInstanceMethod(windowClass, @selector(sendEvent:));
            method_setImplementation(method, reinterpret_cast<IMP>(oldSendEvent));
            oldSendEvent = nil;

            // Delete
            [windowObserver release];
            windowObserver = nil;
        }

    private:
        static BOOL canBecomeKeyWindow(id obj, SEL sel) {
            if (instances.contains(reinterpret_cast<NSWindow *>(obj))) {
            if (g_proxyIndexes->contains(reinterpret_cast<NSWindow *>(obj))) {
                return YES;
            }

@@ -146,7 +247,7 @@
        }

        static BOOL canBecomeMainWindow(id obj, SEL sel) {
            if (instances.contains(reinterpret_cast<NSWindow *>(obj))) {
            if (g_proxyIndexes->contains(reinterpret_cast<NSWindow *>(obj))) {
                return YES;
            }

@@ -158,7 +259,7 @@
        }

        static void setStyleMask(id obj, SEL sel, NSWindowStyleMask styleMask) {
            if (instances.contains(reinterpret_cast<NSWindow *>(obj))) {
            if (g_proxyIndexes->contains(reinterpret_cast<NSWindow *>(obj))) {
                styleMask |= NSWindowStyleMaskFullSizeContentView;
            }

@@ -168,7 +269,7 @@
        }

        static void setTitlebarAppearsTransparent(id obj, SEL sel, BOOL transparent) {
            if (instances.contains(reinterpret_cast<NSWindow *>(obj))) {
            if (g_proxyIndexes->contains(reinterpret_cast<NSWindow *>(obj))) {
                transparent = YES;
            }

@@ -183,28 +284,31 @@
            }

#if 0
        const auto nswindow = reinterpret_cast<NSWindow *>(obj);
        const auto it = instances.find(nswindow);
        if (it == instances.end()) {
            return;
        }
            const auto nswindow = reinterpret_cast<NSWindow *>(obj);
            const auto it = instances.find(nswindow);
            if (it == instances.end()) {
                return;
            }

        NSWindowProxy * const proxy = it.value();
        if (event.type == NSEventTypeLeftMouseDown) {
            proxy->lastMouseDownEvent = event;
            QCoreApplication::processEvents();
            proxy->lastMouseDownEvent = nil;
        }
            NSWindowProxy *proxy = it.value();
            if (event.type == NSEventTypeLeftMouseDown) {
                proxy->lastMouseDownEvent = event;
                QCoreApplication::processEvents();
                proxy->lastMouseDownEvent = nil;
            }
#endif
        }

        static inline const Class windowClass = [NSWindow class];

    private:
        Q_DISABLE_COPY(NSWindowProxy)

        NSWindow *nswindow = nil;

        static inline QWK_NSWindowObserver *windowObserver = nil;

        // NSEvent *lastMouseDownEvent = nil;

        static inline QHash<NSWindow *, NSWindowProxy *> instances = {};

        static inline Class windowClass = nil;

        using setStyleMaskPtr = void (*)(id, SEL, NSWindowStyleMask);
        static inline setStyleMaskPtr oldSetStyleMask = nil;
@@ -222,48 +326,176 @@
        static inline sendEventPtr oldSendEvent = nil;
    };

    using ProxyList = QHash<WId, NSWindowProxy *>;
    Q_GLOBAL_STATIC(ProxyList, g_proxyList);

    static inline NSWindow *mac_getNSWindow(const WId windowId) {
        const auto nsview = reinterpret_cast<NSView *>(windowId);
        if (!nsview) {
            return nil;
        }
        return [nsview window];
    }

    static inline void cleanupProxy() {
        if (g_proxyList()->isEmpty()) {
            return;
        }
        const auto &data = *g_proxyList();
        qDeleteAll(data);
        g_proxyList()->clear();
    }

    static inline NSWindowProxy *ensureWindowProxy(const WId windowId) {
        auto it = g_proxyList()->find(windowId);
        if (it == g_proxyList()->end()) {
            NSWindow *nswindow = mac_getNSWindow(windowId);
            if (!nswindow) {
                return nil;
            }
            const auto proxy = new NSWindowProxy(nswindow);
            it = g_proxyList()->insert(windowId, proxy);
        if (g_proxyList->isEmpty()) {
            NSWindowProxy::replaceImplementations();
        }
        static bool cleanerInstalled = false;
        if (!cleanerInstalled) {
            cleanerInstalled = true;
            qAddPostRoutine(cleanupProxy);

        auto it = g_proxyList->find(windowId);
        if (it == g_proxyList->end()) {
            NSWindow *nswindow = mac_getNSWindow(windowId);
            const auto proxy = new NSWindowProxy(nswindow);
            it = g_proxyList->insert(windowId, proxy);
        }
        return it.value();
    }

    CocoaWindowContext::CocoaWindowContext() {
    static inline void releaseWindowProxy(const WId windowId) {
        if (auto proxy = g_proxyList->take(windowId)) {
            proxy->setSystemTitleBarVisible(true);
            delete proxy;
        } else {
            return;
        }

        if (g_proxyList->isEmpty()) {
            NSWindowProxy::restoreImplementations();
        }
    }

    class CocoaWindowEventFilter : public SharedEventFilter {
    public:
        explicit CocoaWindowEventFilter(AbstractWindowContext *context);
        ~CocoaWindowEventFilter() override;

        enum WindowStatus {
            Idle,
            WaitingRelease,
            PreparingMove,
            Moving,
        };

    protected:
        bool sharedEventFilter(QObject *object, QEvent *event) override;

    private:
        AbstractWindowContext *m_context;
        bool m_cursorShapeChanged;
        WindowStatus m_windowStatus;
    };

    CocoaWindowEventFilter::CocoaWindowEventFilter(AbstractWindowContext *context)
        : m_context(context), m_cursorShapeChanged(false), m_windowStatus(Idle) {
        m_context->installSharedEventFilter(this);
    }

    CocoaWindowEventFilter::~CocoaWindowEventFilter() = default;

    bool CocoaWindowEventFilter::sharedEventFilter(QObject *obj, QEvent *event) {
        Q_UNUSED(obj)

        auto type = event->type();
        if (type < QEvent::MouseButtonPress || type > QEvent::MouseMove) {
            return false;
        }
        auto host = m_context->host();
        auto window = m_context->window();
        auto delegate = m_context->delegate();
        auto me = static_cast<const QMouseEvent *>(event);

        QPoint scenePos = getMouseEventScenePos(me);
        QPoint globalPos = getMouseEventGlobalPos(me);

        bool inTitleBar = m_context->isInTitleBarDraggableArea(scenePos);
        switch (type) {
            case QEvent::MouseButtonPress: {
                switch (me->button()) {
                    case Qt::LeftButton: {
                        if (inTitleBar) {
                            // If we call startSystemMove() now but release the mouse without actual
                            // movement, there will be no MouseReleaseEvent, so we defer it when the
                            // mouse is actually moving for the first time
                            m_windowStatus = PreparingMove;
                            event->accept();
                            return true;
                        }
                        break;
                    }
                    case Qt::RightButton: {
                        m_context->showSystemMenu(globalPos);
                        break;
                    }
                    default:
                        break;
                }
                m_windowStatus = WaitingRelease;
                break;
            }

            case QEvent::MouseButtonRelease: {
                switch (m_windowStatus) {
                    case PreparingMove:
                    case Moving: {
                        m_windowStatus = Idle;
                        event->accept();
                        return true;
                    }
                    case WaitingRelease: {
                        m_windowStatus = Idle;
                        break;
                    }
                    default: {
                        if (inTitleBar) {
                            event->accept();
                            return true;
                        }
                        break;
                    }
                }
                break;
            }

            case QEvent::MouseMove: {
                switch (m_windowStatus) {
                    case Moving: {
                        return true;
                    }
                    case PreparingMove: {
                        m_windowStatus = Moving;
                        startSystemMove(window);
                        event->accept();
                        return true;
                    }
                    default:
                        break;
                }
                break;
            }

            case QEvent::MouseButtonDblClick: {
                if (me->button() == Qt::LeftButton && inTitleBar &&
                    !delegate->isHostSizeFixed(host)) {
                    Qt::WindowStates windowState = delegate->getWindowState(host);
                    if (!(windowState & Qt::WindowFullScreen)) {
                        if (windowState & Qt::WindowMaximized) {
                            delegate->setWindowState(host, windowState & ~Qt::WindowMaximized);
                        } else {
                            delegate->setWindowState(host, windowState | Qt::WindowMaximized);
                        }
                        event->accept();
                        return true;
                    }
                }
                break;
            }

            default:
                break;
        }
        return false;
    }

    CocoaWindowContext::CocoaWindowContext() : AbstractWindowContext() {
        cocoaWindowEventFilter = std::make_unique<CocoaWindowEventFilter>(this);
    }

    CocoaWindowContext::~CocoaWindowContext() {
        releaseWindowProxy(windowId);
    }

    QString CocoaWindowContext::key() const {
@@ -271,19 +503,45 @@
    }

    void CocoaWindowContext::virtual_hook(int id, void *data) {
        switch (id) {
            case SystemButtonAreaChangedHook: {
                // TODO: mac system button rect updated
                return;
            }

            default:
                break;
        }
        AbstractWindowContext::virtual_hook(id, data);
    }

    bool CocoaWindowContext::setupHost() {
#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
        m_windowHandle->setProperty("_q_mac_wantsLayer", 1);
#endif
        WId winId = m_windowHandle->winId();
        ensureWindowProxy(winId)->setSystemTitleBarVisible(false);
        // Cache window ID
        windowId = winId;
        return true;
    void CocoaWindowContext::winIdChanged() {
        // If the original window id is valid, remove all resources related
        if (windowId) {
            releaseWindowProxy(windowId);
            windowId = 0;
        }

        if (!m_windowHandle) {
            return;
        }

        // Allocate new resources
        windowId = m_windowHandle->winId();
        ensureWindowProxy(windowId)->setSystemTitleBarVisible(false);
    }

    bool CocoaWindowContext::windowAttributeChanged(const QString &key, const QVariant &attribute,
                                                    const QVariant &oldAttribute) {
        if (key == QStringLiteral("no-system-buttons")) {
            if (attribute.toBool()) {
                // TODO: set off
            } else {
                // TODO: set on
            }
            return true;
        }
        return false;
    }

}

#include "cocoawindowcontext.moc"