/****************************************************************************
**
** Copyright (C) 2008-2012 NVIDIA Corporation.
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of Qt 3D Studio.
**
** $QT_BEGIN_LICENSE:GPL$
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** accordance with the commercial license agreement provided with the
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 or (at your option) 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.GPL3
** included in the packaging of this file. Please review the following
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#pragma once
#ifndef QT3DS_OFFSCREEN_RENDER_KEY_H
#define QT3DS_OFFSCREEN_RENDER_KEY_H
#include "Qt3DSRender.h"
#include "foundation/StringTable.h"
#include "foundation/Qt3DSDiscriminatedUnion.h"

namespace qt3ds {
namespace foundation {

    template <>
    struct DestructTraits<CRegisteredString>
    {
        void destruct(CRegisteredString &) {}
    };
}
}

namespace qt3ds {
namespace render {
    struct OffscreenRendererKeyTypes
    {
        enum Enum {
            NoOffscreenRendererKey = 0,
            RegisteredString,
            VoidPtr,
        };
    };

    template <typename TDType>
    struct SOffscreenRendererKeyTypeMap
    {
    };
    template <>
    struct SOffscreenRendererKeyTypeMap<CRegisteredString>
    {
        enum { KeyType = OffscreenRendererKeyTypes::RegisteredString };
    };
    template <>
    struct SOffscreenRendererKeyTypeMap<void *>
    {
        enum { KeyType = OffscreenRendererKeyTypes::VoidPtr };
    };

    struct SOffscreenRendererKeyUnionTraits
    {
        typedef OffscreenRendererKeyTypes::Enum TIdType;
        enum {
            TBufferSize = sizeof(CRegisteredString),
        };

        static TIdType getNoDataId() { return OffscreenRendererKeyTypes::NoOffscreenRendererKey; }

        template <typename TDataType>
        static TIdType getType()
        {
            return (TIdType)SOffscreenRendererKeyTypeMap<TDataType>::KeyType;
        }

        template <typename TRetType, typename TVisitorType>
        static TRetType visit(char *inData, TIdType inType, TVisitorType inVisitor)
        {
            switch (inType) {
            case OffscreenRendererKeyTypes::RegisteredString:
                return inVisitor(*NVUnionCast<CRegisteredString *>(inData));
            case OffscreenRendererKeyTypes::VoidPtr:
                return inVisitor(*NVUnionCast<void **>(inData));
            default:
                QT3DS_ASSERT(false);
            case OffscreenRendererKeyTypes::NoOffscreenRendererKey:
                return inVisitor();
            }
        }

        template <typename TRetType, typename TVisitorType>
        static TRetType visit(const char *inData, TIdType inType, TVisitorType inVisitor)
        {
            switch (inType) {
            case OffscreenRendererKeyTypes::RegisteredString:
                return inVisitor(*NVUnionCast<const CRegisteredString *>(inData));
            case OffscreenRendererKeyTypes::VoidPtr:
                return inVisitor(*NVUnionCast<const void **>(inData));
            default:
                QT3DS_ASSERT(false);
            case OffscreenRendererKeyTypes::NoOffscreenRendererKey:
                return inVisitor();
            }
        }
    };

    typedef qt3ds::foundation::
        DiscriminatedUnion<qt3ds::foundation::
                               DiscriminatedUnionGenericBase<SOffscreenRendererKeyUnionTraits,
                                                             SOffscreenRendererKeyUnionTraits::
                                                                 TBufferSize>,
                           SOffscreenRendererKeyUnionTraits::TBufferSize>
            TOffscreenRendererKeyUnionType;

    struct SOffscreenRendererKey : public TOffscreenRendererKeyUnionType
    {
        typedef TOffscreenRendererKeyUnionType TBase;
        SOffscreenRendererKey() {}
        SOffscreenRendererKey(const CRegisteredString &str)
            : TBase(str)
        {
        }
        SOffscreenRendererKey(void *key)
            : TBase(key)
        {
        }
        SOffscreenRendererKey(const SOffscreenRendererKey &other)
            : TBase(static_cast<const TBase &>(other))
        {
        }
        SOffscreenRendererKey &operator=(const SOffscreenRendererKey &other)
        {
            TBase::operator=(other);
            return *this;
        }
    };
}
}

#endif