#ifndef GRAPHICSWINDOWEX_H
#define GRAPHICSWINDOWEX_H

#include <QObject>
#include <osgViewer/GraphicsWindow>

#include <QOffscreenSurface>
#include <QOpenGLContext>
#include <QOpenGLFramebufferObject>

/// Needed for mixing osg rendering with Qt 2D drawing using QPainter...
/// See http://forum.openscenegraph.org/viewtopic.php?t=15627&view=previous

class GraphicsWindowEx : public osgViewer::GraphicsWindowEmbedded {
public:    
    GraphicsWindowEx(osg::GraphicsContext::Traits* traits);
    GraphicsWindowEx(int x, int y, int width, int height);
    ~GraphicsWindowEx() override;

    virtual bool isSameKindAs(const osg::Object* object) const
    {
        return dynamic_cast<const GraphicsWindowEx*>(object) != 0;
    }
    virtual const char* libraryName() const
    {
        return "";
    }
    virtual const char* className() const
    {
        return "GraphicsWindowEx";
    }

    // dummy implementations, assume that graphics context is *always* current and valid.
    virtual bool valid() const
    {
        return true;
    }
    bool isRealizedImplementation() const override {
        return isRealized_;
    }
    bool realizeImplementation() override;
    bool makeCurrentImplementation() override;
    void closeImplementation() override;
    bool releaseContextImplementation() override;
    void swapBuffersImplementation() override;

    bool SetSharedContext(QOpenGLContext* sharedContext);
    void UpdateWindowScale(float scale) {
        windowScale_ = scale;
    }
    unsigned int GetFrameBufferId() {
        isRenderDonwn_ = true;
        return frameBufferId_;
    }

    void ReizeWindow(int width, int height);

public:
    void keyPressEvent(class QKeyEvent* event);
    void keyReleaseEvent(class QKeyEvent* event);
    void mousePressEvent(class QMouseEvent* event);
    void mouseReleaseEvent(class QMouseEvent* event);
    void mouseDoubleClickEvent(class QMouseEvent* event);
    void mouseMoveEvent(class QMouseEvent* event);
    void wheelEvent(class QWheelEvent* event);

protected:
    void InitOffScreenContext();
    void InitFrameBuffer();

private:
    std::unique_ptr<QOffscreenSurface> offScreenSurface_{nullptr};
    std::unique_ptr<QOpenGLContext> offScreenContext_{ nullptr };
    std::unique_ptr<QOpenGLFramebufferObject> renderFramebuffer_{ nullptr };
    std::unique_ptr<QOpenGLFramebufferObject> sharedFrameBuffer_{ nullptr };

    QOpenGLContext* sharedContext_{ nullptr };

    bool isSharedContextSet_{ false };
    bool isRealized_{ false };
    bool isFrameBufferInitialized_{ false };
    bool isRenderDonwn_{ false };
    unsigned int frameBufferId_{ 0 };

    float windowScale_{ 1.0f };

};

#endif // GRAPHICSWINDOWEX_H