#ifndef OPENXR_VIEW_HPP
#define OPENXR_VIEW_HPP

#include <cassert>
#include "openxrmanager.hpp"
#include "openxrswapchain.hpp"

struct XrSwapchainSubImage;

namespace MWVR
{
    /// \brief Manipulates a slave camera by replacing its framebuffer with one destined for openxr
    class VRView : public osg::Referenced
    {
    public:

        class InitialDrawCallback : public osg::Camera::DrawCallback
        {
        public:
            virtual void operator()(osg::RenderInfo& renderInfo) const;
        };

        class UpdateSlaveCallback : public osg::View::Slave::UpdateSlaveCallback
        {
        public:
            UpdateSlaveCallback(osg::ref_ptr<VRView> view, osg::GraphicsContext* gc)
                : mView(view), mGC(gc)
            {}

            void updateSlave(osg::View& view, osg::View::Slave& slave) override;

        private:
            osg::ref_ptr<OpenXRManager> mXR;
            osg::ref_ptr<VRView> mView;
            osg::ref_ptr<osg::GraphicsContext> mGC;
        };

    public:
        VRView(std::string name, SwapchainConfig config, osg::ref_ptr<osg::State> state);
        virtual ~VRView();

    public:
        //! Prepare for render (set FBO)
        virtual void prerenderCallback(osg::RenderInfo& renderInfo);
        //! Finalize render
        virtual void postrenderCallback(osg::RenderInfo& renderInfo);
        //! Create camera for this view
        osg::Camera* createCamera(int order, const osg::Vec4& clearColor, osg::GraphicsContext* gc);
        //! Get the view surface
        OpenXRSwapchain& swapchain(void) { return *mSwapchain; }
        //! Present to the openxr swapchain
        void swapBuffers(osg::GraphicsContext* gc);

    public:
        SwapchainConfig mSwapchainConfig;
        std::unique_ptr<OpenXRSwapchain> mSwapchain;
        std::string mName{};
        bool mRendering{ false };
    };
}

#endif