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#ifndef SHAREDTEXTUREPROVIDER_H
#define SHAREDTEXTUREPROVIDER_H

#include <QOpenGLFunctions>
#include <QQuickImageProvider>
#include <QtQuick/QSGTexture>
#include <QScopedPointer>
#include <QHash>

#include <QtWaylandClient/private/qwaylandserverbufferintegration_p.h>

QT_BEGIN_NAMESPACE

class TextureSharingExtension;

class SharedTextureRegistry : public QObject
{
    Q_OBJECT
public:
    SharedTextureRegistry();
    ~SharedTextureRegistry() override;

    const QtWaylandClient::QWaylandServerBuffer *bufferForId(const QString &id) const;
    void requestBuffer(const QString &id);
    void abandonBuffer(const QString &id);

    static bool preinitialize();

public slots:
    void receiveBuffer(QtWaylandClient::QWaylandServerBuffer *buffer, const QString &id);

signals:
    void replyReceived(const QString &id);

private slots:
    void handleExtensionActive();

private:
    TextureSharingExtension *m_extension = nullptr;
    QHash<QString, QtWaylandClient::QWaylandServerBuffer *> m_buffers;
    QStringList m_pendingBuffers;
};

class SharedTextureProvider : public QQuickAsyncImageProvider
{
public:
    SharedTextureProvider();
    ~SharedTextureProvider() override;

    QQuickImageResponse *requestImageResponse(const QString &id, const QSize &requestedSize) override;

private:
    SharedTextureRegistry *m_registry = nullptr;
    bool m_sharingAvailable = false;
};

class SharedTexture : public QSGTexture
{
    Q_OBJECT
public:
    SharedTexture(QtWaylandClient::QWaylandServerBuffer *buffer);

    int textureId() const override;
    QSize textureSize() const override;
    bool hasAlphaChannel() const override;
    bool hasMipmaps() const override;

    void bind() override;

private:
    void updateGLTexture() const;
    QtWaylandClient::QWaylandServerBuffer *m_buffer = nullptr;
    mutable QOpenGLTexture *m_tex = nullptr;
};


QT_END_NAMESPACE

#endif // SHAREDTEXTUREPROVIDER_H