// Copyright (c) 2012-2022 Wojciech Figat. All rights reserved.

#include "ShaderProcessing.h"

#if COMPILE_WITH_SHADER_COMPILER

#include "Engine/Core/Log.h"

VertexShaderMeta::InputType ShaderProcessing::ParseInputType(const Token& token)
{
    struct InputDesc
    {
        VertexShaderMeta::InputType e;
        const char* s;
    };

#define _PARSE_ENTRY(x) { VertexShaderMeta::InputType::x, #x }
    const InputDesc formats[] =
    {
        _PARSE_ENTRY(Invalid),
        _PARSE_ENTRY(POSITION),
        _PARSE_ENTRY(COLOR),
        _PARSE_ENTRY(TEXCOORD),
        _PARSE_ENTRY(NORMAL),
        _PARSE_ENTRY(TANGENT),
        _PARSE_ENTRY(BITANGENT),
        _PARSE_ENTRY(ATTRIBUTE),
        _PARSE_ENTRY(BLENDINDICES),
        _PARSE_ENTRY(BLENDWEIGHT),
    };
#undef _PARSE_ENTRY

    for (int32 i = 0; i < ARRAY_COUNT(formats); i++)
    {
        if (token == formats[i].s)
            return formats[i].e;
    }

    return VertexShaderMeta::InputType::Invalid;
}

PixelFormat ShaderProcessing::ParsePixelFormat(const Token& token)
{
    struct DataDesc
    {
        PixelFormat e;
        const char* s;
    };

#define _PARSE_ENTRY(x) { PixelFormat::x, #x }
    const DataDesc formats[] =
    {
        _PARSE_ENTRY(Unknown),
        _PARSE_ENTRY(R32G32B32A32_Float),
        _PARSE_ENTRY(R32G32B32A32_UInt),
        _PARSE_ENTRY(R32G32B32A32_SInt),
        _PARSE_ENTRY(R32G32B32_Float),
        _PARSE_ENTRY(R32G32B32_UInt),
        _PARSE_ENTRY(R32G32B32_SInt),
        _PARSE_ENTRY(R16G16B16A16_Float),
        _PARSE_ENTRY(R16G16B16A16_UNorm),
        _PARSE_ENTRY(R16G16B16A16_UInt),
        _PARSE_ENTRY(R16G16B16A16_SNorm),
        _PARSE_ENTRY(R16G16B16A16_SInt),
        _PARSE_ENTRY(R32G32_Float),
        _PARSE_ENTRY(R32G32_UInt),
        _PARSE_ENTRY(R32G32_SInt),
        _PARSE_ENTRY(R10G10B10A2_UNorm),
        _PARSE_ENTRY(R10G10B10A2_UInt),
        _PARSE_ENTRY(R11G11B10_Float),
        _PARSE_ENTRY(R8G8B8A8_UNorm),
        _PARSE_ENTRY(R8G8B8A8_UNorm_sRGB),
        _PARSE_ENTRY(R8G8B8A8_UInt),
        _PARSE_ENTRY(R8G8B8A8_SNorm),
        _PARSE_ENTRY(R8G8B8A8_SInt),
        _PARSE_ENTRY(R16G16_Float),
        _PARSE_ENTRY(R16G16_UNorm),
        _PARSE_ENTRY(R16G16_UInt),
        _PARSE_ENTRY(R16G16_SNorm),
        _PARSE_ENTRY(R16G16_SInt),
        _PARSE_ENTRY(R32_Float),
        _PARSE_ENTRY(R32_UInt),
        _PARSE_ENTRY(R32_SInt),
        _PARSE_ENTRY(R8G8_UNorm),
        _PARSE_ENTRY(R8G8_UInt),
        _PARSE_ENTRY(R8G8_SNorm),
        _PARSE_ENTRY(R8G8_SInt),
        _PARSE_ENTRY(R16_Float),
        _PARSE_ENTRY(R16_UNorm),
        _PARSE_ENTRY(R16_UInt),
        _PARSE_ENTRY(R16_SNorm),
        _PARSE_ENTRY(R16_SInt),
        _PARSE_ENTRY(R8_UNorm),
        _PARSE_ENTRY(R8_UInt),
        _PARSE_ENTRY(R8_SNorm),
        _PARSE_ENTRY(R8_SInt),
        _PARSE_ENTRY(A8_UNorm),
        _PARSE_ENTRY(R1_UNorm),
        _PARSE_ENTRY(R8G8_B8G8_UNorm),
        _PARSE_ENTRY(G8R8_G8B8_UNorm),
        _PARSE_ENTRY(BC1_UNorm),
        _PARSE_ENTRY(BC1_UNorm_sRGB),
        _PARSE_ENTRY(BC2_UNorm),
        _PARSE_ENTRY(BC2_UNorm_sRGB),
        _PARSE_ENTRY(BC3_UNorm),
        _PARSE_ENTRY(BC3_UNorm_sRGB),
        _PARSE_ENTRY(BC4_UNorm),
        _PARSE_ENTRY(BC4_SNorm),
        _PARSE_ENTRY(BC5_UNorm),
        _PARSE_ENTRY(BC5_SNorm),
        _PARSE_ENTRY(B5G6R5_UNorm),
        _PARSE_ENTRY(B5G5R5A1_UNorm),
        _PARSE_ENTRY(B8G8R8A8_UNorm),
        _PARSE_ENTRY(B8G8R8X8_UNorm),
        _PARSE_ENTRY(B8G8R8A8_UNorm_sRGB),
        _PARSE_ENTRY(B8G8R8X8_UNorm_sRGB),
        _PARSE_ENTRY(BC6H_Uf16),
        _PARSE_ENTRY(BC6H_Sf16),
        _PARSE_ENTRY(BC7_UNorm),
        _PARSE_ENTRY(BC7_UNorm_sRGB),
    };
#undef _PARSE_ENTRY

    for (int32 i = 0; i < ARRAY_COUNT(formats); i++)
    {
        if (token.EqualsIgnoreCase(formats[i].s))
            return formats[i].e;
    }

    return PixelFormat::Unknown;
}

ShaderFlags ShaderProcessing::ParseShaderFlags(const Token& token)
{
    struct DataDesc
    {
        ShaderFlags e;
        const char* s;
    };

#define _PARSE_ENTRY(x) { ShaderFlags::x, #x }
    const DataDesc data[] =
    {
        _PARSE_ENTRY(Default),
        _PARSE_ENTRY(Hidden),
        _PARSE_ENTRY(NoFastMath),
        _PARSE_ENTRY(VertexToGeometryShader),
    };
    static_assert(ARRAY_COUNT(data) == 4, "Invalid amount of Shader Flag data entries.");
#undef _PARSE_ENTRY

    for (int32 i = 0; i < ARRAY_COUNT(data); i++)
    {
        if (token.EqualsIgnoreCase(data[i].s))
            return data[i].e;
    }

    return ShaderFlags::Default;
}

#endif