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#pragma once
#ifndef QT3DS_RENDER_QT3DS_RENDER_DRAW_INDIRECT_BUFFER_H
#define QT3DS_RENDER_QT3DS_RENDER_DRAW_INDIRECT_BUFFER_H
#include "foundation/Qt3DSOption.h"
#include "foundation/Utils.h"
#include "foundation/StringTable.h"
#include "render/Qt3DSRenderDataBuffer.h"

namespace qt3ds {
namespace render {

    using namespace foundation;

    // forward declaration
    class NVRenderContextImpl;

    struct DrawArraysIndirectCommand
    {
        QT3DSU32 count;
        QT3DSU32 primCount;
        QT3DSU32 first;
        QT3DSU32 baseInstance;
    };

    struct DrawElementsIndirectCommand
    {
        QT3DSU32 count;
        QT3DSU32 primCount;
        QT3DSU32 firstIndex;
        QT3DSU32 baseVertex;
        QT3DSU32 baseInstance;
    };

    ///< Constant (uniform) buffer representation
    class NVRenderDrawIndirectBuffer : public NVRenderDataBuffer
    {
    public:
        /**
         * @brief constructor
         *
         * @param[in] context		Pointer to context
         * @param[in] size			Size of the buffer
         * @param[in] usage			Usage of the buffer (e.g. static, dynamic...)
         * @param[in] data			A pointer to the buffer data that is allocated by the
         * application.
         *
         * @return No return.
         */
        NVRenderDrawIndirectBuffer(NVRenderContextImpl &context, size_t size,
                                   NVRenderBufferUsageType::Enum usageType, NVDataRef<QT3DSU8> data);

        ///< destructor
        virtual ~NVRenderDrawIndirectBuffer();

        /**
         * @brief bind the buffer bypasses the context state
         *
         * @return no return.
         */
        void Bind() override;

        /**
         * @brief update the buffer to hardware
         *
         * @return no return.
         */
        virtual void Update();

        /**
         * @brief update a piece of memory directly within the storage buffer
         *
         * Note: When you use this function you should know what you are doing.
         *		 The memory layout within C++ must exactly match the memory layout in the
         *shader.
         *		 We use std140 (430) layout which guarantees a specific layout behavior across
         *all HW vendors.
         *		 How the memory layout is computed can be found in the GL spec.
         *
         * @param[in] offset	offset into storage buffer
         * @param[in] data		pointer to data
         *
         * @return no return
         */
        void UpdateData(QT3DSI32 offset, NVDataRef<QT3DSU8> data);

        /**
         * @brief get the backend object handle
         *
         * @return the backend object handle.
         */
        NVRenderBackend::NVRenderBackendBufferObject GetBuffertHandle() const override
        {
            return m_BufferHandle;
        }

        // this will be obsolete
        const void *GetImplementationHandle() const override
        {
            return reinterpret_cast<void *>(m_BufferHandle);
        }

        /**
         * @brief create a NVRenderDrawIndirectBuffer object
         *
         * @param[in] context		Pointer to context
         * @param[in] size			Size of the buffer
         * @param[in] usage			Usage of the buffer (e.g. static, dynamic...)
         * @param[in] data			A pointer to the buffer data that is allocated by the
         * application.
         *
         * @return the buffer object or NULL
         */
        static NVRenderDrawIndirectBuffer *Create(NVRenderContextImpl &context,
                                                  NVRenderBufferUsageType::Enum usageType,
                                                  size_t size, NVConstDataRef<QT3DSU8> bufferData);

    private:
        bool m_Dirty; ///< true if buffer is dirty
    };
}
}

#endif