/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the config.tests of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QWAYLANDWINDOW_H
#define QWAYLANDWINDOW_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include <QtCore/QWaitCondition>
#include <QtCore/QMutex>
#include <QtCore/QReadWriteLock>

#include <QtGui/QIcon>
#include <QtCore/QVariant>
#include <QtCore/QLoggingCategory>
#include <QtCore/QElapsedTimer>

#include <qpa/qplatformwindow.h>

#include <QtWaylandClient/private/qwayland-wayland.h>
#include <QtWaylandClient/private/qwaylanddisplay_p.h>
#include <QtWaylandClient/qtwaylandclientglobal.h>

struct wl_egl_window;

QT_BEGIN_NAMESPACE

namespace QtWaylandClient {

Q_DECLARE_LOGGING_CATEGORY(lcWaylandBackingstore)

class QWaylandDisplay;
class QWaylandBuffer;
class QWaylandShellSurface;
class QWaylandSubSurface;
class QWaylandAbstractDecoration;
class QWaylandInputDevice;
class QWaylandScreen;
class QWaylandShmBackingStore;
class QWaylandPointerEvent;
class QWaylandSurface;

class Q_WAYLAND_CLIENT_EXPORT QWaylandWindow : public QObject, public QPlatformWindow
{
    Q_OBJECT
public:
    enum WindowType {
        Shm,
        Egl,
        Vulkan
    };

    QWaylandWindow(QWindow *window, QWaylandDisplay *display);
    ~QWaylandWindow() override;

    // Keep Toplevels position on the top left corner of their screen
    static inline bool fixedToplevelPositions = true;

    virtual WindowType windowType() const = 0;
    virtual void ensureSize();
    WId winId() const override;
    void setVisible(bool visible) override;
    void setParent(const QPlatformWindow *parent) override;

    QString windowTitle() const;
    void setWindowTitle(const QString &title) override;

    inline QIcon windowIcon() const;
    void setWindowIcon(const QIcon &icon) override;

    void setGeometry(const QRect &rect) override;
    void resizeFromApplyConfigure(const QSize &sizeWithMargins, const QPoint &offset = {0, 0});

    void applyConfigureWhenPossible(); //rename to possible?

    void attach(QWaylandBuffer *buffer, int x, int y);
    void attachOffset(QWaylandBuffer *buffer);
    QPoint attachOffset() const;

    void damage(const QRect &rect);

    void safeCommit(QWaylandBuffer *buffer, const QRegion &damage);
    void handleExpose(const QRegion &region);
    void commit(QWaylandBuffer *buffer, const QRegion &damage);

    void commit();

    bool waitForFrameSync(int timeout);

    QMargins frameMargins() const override;
    QSize surfaceSize() const;
    QRect windowContentGeometry() const;
    QPointF mapFromWlSurface(const QPointF &surfacePosition) const;

    QWaylandSurface *waylandSurface() const { return mSurface.data(); }
    ::wl_surface *wlSurface();
    static QWaylandWindow *fromWlSurface(::wl_surface *surface);

    QWaylandDisplay *display() const { return mDisplay; }
    QWaylandShellSurface *shellSurface() const;
    QWaylandSubSurface *subSurfaceWindow() const;
    QWaylandScreen *waylandScreen() const;

    void handleContentOrientationChange(Qt::ScreenOrientation orientation) override;
    void setOrientationMask(Qt::ScreenOrientations mask);

    void setWindowState(Qt::WindowStates states) override;
    void setWindowFlags(Qt::WindowFlags flags) override;
    void handleWindowStatesChanged(Qt::WindowStates states);
    Qt::WindowStates windowStates() const;

    void raise() override;
    void lower() override;

    void setMask(const QRegion &region) override;

    qreal scale() const;
    qreal devicePixelRatio() const override;

    void requestActivateWindow() override;
    bool isExposed() const override;
    bool isActive() const override;

    QWaylandAbstractDecoration *decoration() const;

    void handleMouse(QWaylandInputDevice *inputDevice, const QWaylandPointerEvent &e);

    bool touchDragDecoration(QWaylandInputDevice *inputDevice, const QPointF &local, const QPointF &global,
                             Qt::TouchPointState state, Qt::KeyboardModifiers mods);

    bool createDecoration();

#if QT_CONFIG(cursor)
    void setMouseCursor(QWaylandInputDevice *device, const QCursor &cursor);
    void restoreMouseCursor(QWaylandInputDevice *device);
#endif

    QWaylandWindow *transientParent() const;

    QMutex *resizeMutex() { return &mResizeLock; }
    void doApplyConfigure();
    void setCanResize(bool canResize);

    bool setMouseGrabEnabled(bool grab) override;
    static QWaylandWindow *mouseGrab() { return mMouseGrab; }

    void sendProperty(const QString &name, const QVariant &value);
    void setProperty(const QString &name, const QVariant &value);

    QVariantMap properties() const;
    QVariant property(const QString &name);
    QVariant property(const QString &name, const QVariant &defaultValue);

    void setBackingStore(QWaylandShmBackingStore *backingStore) { mBackingStore = backingStore; }
    QWaylandShmBackingStore *backingStore() const { return mBackingStore; }

    bool setKeyboardGrabEnabled(bool) override { return false; }
    void propagateSizeHints() override;
    void addAttachOffset(const QPoint point);

    bool startSystemResize(Qt::Edges edges) override;
    bool startSystemMove() override;

    void timerEvent(QTimerEvent *event) override;
    void requestUpdate() override;
    void handleUpdate();
    void deliverUpdateRequest() override;

    void addChildPopup(QWaylandWindow* child);
    void removeChildPopup(QWaylandWindow* child);
    void closeChildPopups();

public slots:
    void applyConfigure();

signals:
    void wlSurfaceCreated();
    void wlSurfaceDestroyed();

protected:
    QWaylandDisplay *mDisplay = nullptr;

    // mSurface can be written by the main thread. Other threads should claim a read lock for access
    mutable QReadWriteLock mSurfaceLock;
    QScopedPointer<QWaylandSurface> mSurface;

    QWaylandShellSurface *mShellSurface = nullptr;
    QWaylandSubSurface *mSubSurfaceWindow = nullptr;
    QVector<QWaylandSubSurface *> mChildren;

    QWaylandAbstractDecoration *mWindowDecoration = nullptr;
    bool mMouseEventsInContentArea = false;
    Qt::MouseButtons mMousePressedInContentArea = Qt::NoButton;

    WId mWindowId;
    bool mFrameCallbackTimedOut = false; // Whether the frame callback has timed out
    int mFrameCallbackCheckIntervalTimerId = -1;
    QAtomicInt mWaitingForUpdateDelivery = false;

    bool mWaitingForFrameCallback = false; // Protected by mFrameSyncMutex
    QElapsedTimer mFrameCallbackElapsedTimer; // Protected by mFrameSyncMutex
    struct ::wl_callback *mFrameCallback = nullptr; // Protected by mFrameSyncMutex
    QMutex mFrameSyncMutex;
    QWaitCondition mFrameSyncWait;

    // True when we have called deliverRequestUpdate, but the client has not yet attached a new buffer
    bool mWaitingForUpdate = false;

    QMutex mResizeLock;
    bool mWaitingToApplyConfigure = false;
    bool mCanResize = true;
    bool mResizeDirty = false;
    bool mResizeAfterSwap;
    int mFrameCallbackTimeout = 100;
    QVariantMap m_properties;

    bool mSentInitialResize = false;
    QPoint mOffset;
    int mScale = 1;
    QPlatformScreen *mLastReportedScreen = nullptr;

    QString mWindowTitle;
    QIcon mWindowIcon;

    Qt::WindowFlags mFlags;
    QRegion mMask;
    QRegion mOpaqueArea;
    Qt::WindowStates mLastReportedWindowStates = Qt::WindowNoState;

    QWaylandShmBackingStore *mBackingStore = nullptr;
    QWaylandBuffer *mQueuedBuffer = nullptr;
    QRegion mQueuedBufferDamage;

    QList<QPointer<QWaylandWindow>> mChildPopups;

private:
    void setGeometry_helper(const QRect &rect);
    void initWindow();
    void initializeWlSurface();
    bool shouldCreateShellSurface() const;
    bool shouldCreateSubSurface() const;
    void reset();
    void sendExposeEvent(const QRect &rect);
    static void closePopups(QWaylandWindow *parent);
    QPlatformScreen *calculateScreenFromSurfaceEvents() const;
    void setOpaqueArea(const QRegion &opaqueArea);
    bool isOpaque() const;

    void handleMouseEventWithDecoration(QWaylandInputDevice *inputDevice, const QWaylandPointerEvent &e);
    void handleScreensChanged();
    void sendRecursiveExposeEvent();

    bool mInResizeFromApplyConfigure = false;
    bool lastVisible = false;
    QRect mLastExposeGeometry;

    static const wl_callback_listener callbackListener;
    void handleFrameCallback(struct ::wl_callback* callback);

    static QWaylandWindow *mMouseGrab;

    friend class QWaylandSubSurface;
};

inline QIcon QWaylandWindow::windowIcon() const
{
    return mWindowIcon;
}

inline QPoint QWaylandWindow::attachOffset() const
{
    return mOffset;
}

}

QT_END_NAMESPACE

#endif // QWAYLANDWINDOW_H
