// metal-util.cpp
#include "metal-util.h"

#include "core/slang-math.h"

#include <stdio.h>
#include <stdlib.h>

namespace gfx
{

MTL::PixelFormat MetalUtil::translatePixelFormat(Format format)
{
    switch (format)
    {
    case Format::R32G32B32A32_TYPELESS:
        return MTL::PixelFormatRGBA32Float;
    case Format::R32G32B32_TYPELESS:
        return MTL::PixelFormatInvalid;
    case Format::R32G32_TYPELESS:
        return MTL::PixelFormatRG32Float;
    case Format::R32_TYPELESS:
        return MTL::PixelFormatR32Float;

    case Format::R16G16B16A16_TYPELESS:
        return MTL::PixelFormatRGBA16Float;
    case Format::R16G16_TYPELESS:
        return MTL::PixelFormatRG16Float;
    case Format::R16_TYPELESS:
        return MTL::PixelFormatR16Float;

    case Format::R8G8B8A8_TYPELESS:
        return MTL::PixelFormatRGBA8Unorm;
    case Format::R8G8_TYPELESS:
        return MTL::PixelFormatRG8Unorm;
    case Format::R8_TYPELESS:
        return MTL::PixelFormatR8Unorm;
    case Format::B8G8R8A8_TYPELESS:
        return MTL::PixelFormatBGRA8Unorm;

    case Format::R32G32B32A32_FLOAT:
        return MTL::PixelFormatRGBA32Float;
    case Format::R32G32B32_FLOAT:
        return MTL::PixelFormatInvalid;
    case Format::R32G32_FLOAT:
        return MTL::PixelFormatRG32Float;
    case Format::R32_FLOAT:
        return MTL::PixelFormatR32Float;

    case Format::R16G16B16A16_FLOAT:
        return MTL::PixelFormatRGBA16Float;
    case Format::R16G16_FLOAT:
        return MTL::PixelFormatRG16Float;
    case Format::R16_FLOAT:
        return MTL::PixelFormatR16Float;

    case Format::R32G32B32A32_UINT:
        return MTL::PixelFormatRGBA32Uint;
    case Format::R32G32B32_UINT:
        return MTL::PixelFormatInvalid;
    case Format::R32G32_UINT:
        return MTL::PixelFormatRG32Uint;
    case Format::R32_UINT:
        return MTL::PixelFormatR32Uint;

    case Format::R16G16B16A16_UINT:
        return MTL::PixelFormatRGBA16Uint;
    case Format::R16G16_UINT:
        return MTL::PixelFormatRG16Uint;
    case Format::R16_UINT:
        return MTL::PixelFormatR16Uint;

    case Format::R8G8B8A8_UINT:
        return MTL::PixelFormatRGBA8Uint;
    case Format::R8G8_UINT:
        return MTL::PixelFormatRG8Uint;
    case Format::R8_UINT:
        return MTL::PixelFormatR8Uint;

    case Format::R32G32B32A32_SINT:
        return MTL::PixelFormatRGBA32Sint;
    case Format::R32G32B32_SINT:
        return MTL::PixelFormatInvalid;
    case Format::R32G32_SINT:
        return MTL::PixelFormatRG32Sint;
    case Format::R32_SINT:
        return MTL::PixelFormatR32Sint;

    case Format::R16G16B16A16_SINT:
        return MTL::PixelFormatRGBA16Sint;
    case Format::R16G16_SINT:
        return MTL::PixelFormatRG16Sint;
    case Format::R16_SINT:
        return MTL::PixelFormatR16Sint;

    case Format::R8G8B8A8_SINT:
        return MTL::PixelFormatRGBA8Sint;
    case Format::R8G8_SINT:
        return MTL::PixelFormatRG8Sint;
    case Format::R8_SINT:
        return MTL::PixelFormatR8Sint;

    case Format::R16G16B16A16_UNORM:
        return MTL::PixelFormatRGBA16Unorm;
    case Format::R16G16_UNORM:
        return MTL::PixelFormatRG16Unorm;
    case Format::R16_UNORM:
        return MTL::PixelFormatR16Unorm;

    case Format::R8G8B8A8_UNORM:
        return MTL::PixelFormatRGBA8Unorm;
    case Format::R8G8B8A8_UNORM_SRGB:
        return MTL::PixelFormatRGBA8Unorm_sRGB;
    case Format::R8G8_UNORM:
        return MTL::PixelFormatRG8Unorm;
    case Format::R8_UNORM:
        return MTL::PixelFormatR8Unorm;
    case Format::B8G8R8A8_UNORM:
        return MTL::PixelFormatBGRA8Unorm;
    case Format::B8G8R8A8_UNORM_SRGB:
        return MTL::PixelFormatBGRA8Unorm_sRGB;
    case Format::B8G8R8X8_UNORM:
        return MTL::PixelFormatInvalid;
    case Format::B8G8R8X8_UNORM_SRGB:
        return MTL::PixelFormatInvalid;

    case Format::R16G16B16A16_SNORM:
        return MTL::PixelFormatRGBA16Snorm;
    case Format::R16G16_SNORM:
        return MTL::PixelFormatRG16Snorm;
    case Format::R16_SNORM:
        return MTL::PixelFormatR16Snorm;

    case Format::R8G8B8A8_SNORM:
        return MTL::PixelFormatRGBA8Snorm;
    case Format::R8G8_SNORM:
        return MTL::PixelFormatRG8Snorm;
    case Format::R8_SNORM:
        return MTL::PixelFormatR8Snorm;

    case Format::D32_FLOAT:
        return MTL::PixelFormatDepth32Float;
    case Format::D16_UNORM:
        return MTL::PixelFormatDepth16Unorm;
    case Format::D32_FLOAT_S8_UINT:
        return MTL::PixelFormatDepth32Float_Stencil8;
    case Format::R32_FLOAT_X32_TYPELESS:
        return MTL::PixelFormatInvalid;

    case Format::B4G4R4A4_UNORM:
        return MTL::PixelFormatABGR4Unorm;
    case Format::B5G6R5_UNORM:
        return MTL::PixelFormatB5G6R5Unorm;
    case Format::B5G5R5A1_UNORM:
        return MTL::PixelFormatA1BGR5Unorm;

    case Format::R9G9B9E5_SHAREDEXP:
        return MTL::PixelFormatRGB9E5Float;
    case Format::R10G10B10A2_TYPELESS:
        return MTL::PixelFormatInvalid;
    case Format::R10G10B10A2_UINT:
        return MTL::PixelFormatRGB10A2Uint;
    case Format::R10G10B10A2_UNORM:
        return MTL::PixelFormatRGB10A2Unorm;
    case Format::R11G11B10_FLOAT:
        return MTL::PixelFormatRG11B10Float;

    case Format::BC1_UNORM:
        return MTL::PixelFormatBC1_RGBA;
    case Format::BC1_UNORM_SRGB:
        return MTL::PixelFormatBC1_RGBA_sRGB;
    case Format::BC2_UNORM:
        return MTL::PixelFormatBC2_RGBA;
    case Format::BC2_UNORM_SRGB:
        return MTL::PixelFormatBC2_RGBA_sRGB;
    case Format::BC3_UNORM:
        return MTL::PixelFormatBC3_RGBA;
    case Format::BC3_UNORM_SRGB:
        return MTL::PixelFormatBC3_RGBA_sRGB;
    case Format::BC4_UNORM:
        return MTL::PixelFormatBC4_RUnorm;
    case Format::BC4_SNORM:
        return MTL::PixelFormatBC4_RSnorm;
    case Format::BC5_UNORM:
        return MTL::PixelFormatBC5_RGUnorm;
    case Format::BC5_SNORM:
        return MTL::PixelFormatBC5_RGSnorm;
    case Format::BC6H_UF16:
        return MTL::PixelFormatBC6H_RGBUfloat;
    case Format::BC6H_SF16:
        return MTL::PixelFormatBC6H_RGBFloat;
    case Format::BC7_UNORM:
        return MTL::PixelFormatBC7_RGBAUnorm;
    case Format::BC7_UNORM_SRGB:
        return MTL::PixelFormatBC7_RGBAUnorm_sRGB;

    default:
        return MTL::PixelFormatInvalid;
    }
}

MTL::VertexFormat MetalUtil::translateVertexFormat(Format format)
{
    switch (format)
    {
    case Format::R8G8_UINT:
        return MTL::VertexFormatUChar2;
    // VertexFormatUChar3
    case Format::R8G8B8A8_UINT:
        return MTL::VertexFormatUChar4;
    case Format::R8G8_SINT:
        return MTL::VertexFormatChar2;
    // return VertexFormatChar3
    case Format::R8G8B8A8_SINT:
        return MTL::VertexFormatChar4;
    case Format::R8G8_UNORM:
        return MTL::VertexFormatUChar2Normalized;
    // return VertexFormatUChar3Normalized;
    case Format::R8G8B8A8_UNORM:
        return MTL::VertexFormatUChar4Normalized;
    case Format::R8G8_SNORM:
        return MTL::VertexFormatChar2Normalized;
    // return VertexFormatChar3Normalized
    case Format::R8G8B8A8_SNORM:
        return MTL::VertexFormatChar4Normalized;
    case Format::R16G16_UINT:
        return MTL::VertexFormatUShort2;
    // return VertexFormatUShort3;
    case Format::R16G16B16A16_UINT:
        return MTL::VertexFormatUShort4;
    case Format::R16G16_SINT:
        return MTL::VertexFormatShort2;
    // return VertexFormatShort3;
    case Format::R16G16B16A16_SINT:
        return MTL::VertexFormatShort4;
    case Format::R16G16_UNORM:
        return MTL::VertexFormatUShort2Normalized;
    // return VertexFormatUShort3Normalized;
    case Format::R16G16B16A16_UNORM:
        return MTL::VertexFormatUShort4Normalized;
    case Format::R16G16_SNORM:
        return MTL::VertexFormatShort2Normalized;
    // return VertexFormatShort3Normalized;
    case Format::R16G16B16A16_SNORM:
        return MTL::VertexFormatShort4Normalized;
    case Format::R16G16_FLOAT:
        return MTL::VertexFormatHalf2;
    // return VertexFormatHalf3;
    case Format::R16G16B16A16_FLOAT:
        return MTL::VertexFormatHalf4;
    case Format::R32_FLOAT:
        return MTL::VertexFormatFloat;
    case Format::R32G32_FLOAT:
        return MTL::VertexFormatFloat2;
    case Format::R32G32B32_FLOAT:
        return MTL::VertexFormatFloat3;
    case Format::R32G32B32A32_FLOAT:
        return MTL::VertexFormatFloat4;
    case Format::R32_SINT:
        return MTL::VertexFormatInt;
    case Format::R32G32_SINT:
        return MTL::VertexFormatInt2;
    case Format::R32G32B32_SINT:
        return MTL::VertexFormatInt3;
    case Format::R32G32B32A32_SINT:
        return MTL::VertexFormatInt4;
    case Format::R32_UINT:
        return MTL::VertexFormatUInt;
    case Format::R32G32_UINT:
        return MTL::VertexFormatUInt2;
    case Format::R32G32B32_UINT:
        return MTL::VertexFormatUInt3;
    case Format::R32G32B32A32_UINT:
        return MTL::VertexFormatUInt4;
    // return VertexFormatInt1010102Normalized;
    case Format::R10G10B10A2_UNORM:
        return MTL::VertexFormatUInt1010102Normalized;
    case Format::B4G4R4A4_UNORM:
        return MTL::VertexFormatUChar4Normalized_BGRA;
    case Format::R8_UINT:
        return MTL::VertexFormatUChar;
    case Format::R8_SINT:
        return MTL::VertexFormatChar;
    case Format::R8_UNORM:
        return MTL::VertexFormatUCharNormalized;
    case Format::R8_SNORM:
        return MTL::VertexFormatCharNormalized;
    case Format::R16_UINT:
        return MTL::VertexFormatUShort;
    case Format::R16_SINT:
        return MTL::VertexFormatShort;
    case Format::R16_UNORM:
        return MTL::VertexFormatUShortNormalized;
    case Format::R16_SNORM:
        return MTL::VertexFormatShortNormalized;
    case Format::R16_FLOAT:
        return MTL::VertexFormatHalf;
    case Format::R11G11B10_FLOAT:
        return MTL::VertexFormatFloatRG11B10;
    case Format::R9G9B9E5_SHAREDEXP:
        return MTL::VertexFormatFloatRGB9E5;
    default:
        return MTL::VertexFormatInvalid;
    }
}

bool MetalUtil::isDepthFormat(MTL::PixelFormat format)
{
    switch (format)
    {
    case MTL::PixelFormatDepth16Unorm:
    case MTL::PixelFormatDepth32Float:
    case MTL::PixelFormatDepth24Unorm_Stencil8:
    case MTL::PixelFormatDepth32Float_Stencil8:
        return true;
    default:
        return false;
    }
}

bool MetalUtil::isStencilFormat(MTL::PixelFormat format)
{
    switch (format)
    {
    case MTL::PixelFormatStencil8:
    case MTL::PixelFormatDepth24Unorm_Stencil8:
    case MTL::PixelFormatDepth32Float_Stencil8:
    case MTL::PixelFormatX32_Stencil8:
    case MTL::PixelFormatX24_Stencil8:
        return true;
    default:
        return false;
    }
}

MTL::SamplerMinMagFilter MetalUtil::translateSamplerMinMagFilter(TextureFilteringMode mode)
{
    switch (mode)
    {
    case TextureFilteringMode::Point:
        return MTL::SamplerMinMagFilterNearest;
    case TextureFilteringMode::Linear:
        return MTL::SamplerMinMagFilterLinear;
    default:
        return MTL::SamplerMinMagFilter(0);
    }
}

MTL::SamplerMipFilter MetalUtil::translateSamplerMipFilter(TextureFilteringMode mode)
{
    switch (mode)
    {
    case TextureFilteringMode::Point:
        return MTL::SamplerMipFilterNearest;
    case TextureFilteringMode::Linear:
        return MTL::SamplerMipFilterLinear;
    default:
        return MTL::SamplerMipFilter(0);
    }
}

MTL::SamplerAddressMode MetalUtil::translateSamplerAddressMode(TextureAddressingMode mode)
{
    switch (mode)
    {
    case TextureAddressingMode::Wrap:
        return MTL::SamplerAddressModeRepeat;
    case TextureAddressingMode::ClampToEdge:
        return MTL::SamplerAddressModeClampToEdge;
    case TextureAddressingMode::ClampToBorder:
        return MTL::SamplerAddressModeClampToBorderColor;
    case TextureAddressingMode::MirrorRepeat:
        return MTL::SamplerAddressModeMirrorRepeat;
    case TextureAddressingMode::MirrorOnce:
        return MTL::SamplerAddressModeMirrorClampToEdge;
    default:
        return MTL::SamplerAddressMode(0);
    }
}

MTL::CompareFunction MetalUtil::translateCompareFunction(ComparisonFunc func)
{
    switch (func)
    {
    case ComparisonFunc::Never:
        return MTL::CompareFunctionNever;
    case ComparisonFunc::Less:
        return MTL::CompareFunctionLess;
    case ComparisonFunc::Equal:
        return MTL::CompareFunctionEqual;
    case ComparisonFunc::LessEqual:
        return MTL::CompareFunctionLessEqual;
    case ComparisonFunc::Greater:
        return MTL::CompareFunctionGreater;
    case ComparisonFunc::NotEqual:
        return MTL::CompareFunctionNotEqual;
    case ComparisonFunc::GreaterEqual:
        return MTL::CompareFunctionGreaterEqual;
    case ComparisonFunc::Always:
        return MTL::CompareFunctionAlways;
    default:
        return MTL::CompareFunction(0);
    }
}

MTL::StencilOperation MetalUtil::translateStencilOperation(StencilOp op)
{
    switch (op)
    {
    case StencilOp::Keep:
        return MTL::StencilOperationKeep;
    case StencilOp::Zero:
        return MTL::StencilOperationZero;
    case StencilOp::Replace:
        return MTL::StencilOperationReplace;
    case StencilOp::IncrementSaturate:
        return MTL::StencilOperationIncrementClamp;
    case StencilOp::DecrementSaturate:
        return MTL::StencilOperationDecrementClamp;
    case StencilOp::Invert:
        return MTL::StencilOperationInvert;
    case StencilOp::IncrementWrap:
        return MTL::StencilOperationIncrementWrap;
    case StencilOp::DecrementWrap:
        return MTL::StencilOperationDecrementWrap;
    default:
        return MTL::StencilOperation(0);
    }
}

MTL::VertexStepFunction MetalUtil::translateVertexStepFunction(InputSlotClass slotClass)
{
    switch (slotClass)
    {
    case InputSlotClass::PerVertex:
        return MTL::VertexStepFunctionPerVertex;
    case InputSlotClass::PerInstance:
        return MTL::VertexStepFunctionPerInstance;
    default:
        return MTL::VertexStepFunctionPerVertex;
    }
}

MTL::PrimitiveType MetalUtil::translatePrimitiveType(PrimitiveTopology topology)
{
    switch (topology)
    {
    case PrimitiveTopology::TriangleList:
        return MTL::PrimitiveTypeTriangle;
    case PrimitiveTopology::TriangleStrip:
        return MTL::PrimitiveTypeTriangleStrip;
    case PrimitiveTopology::PointList:
        return MTL::PrimitiveTypePoint;
    case PrimitiveTopology::LineList:
        return MTL::PrimitiveTypeLine;
    case PrimitiveTopology::LineStrip:
        return MTL::PrimitiveTypeLineStrip;
    default:
        return MTL::PrimitiveType(0);
    }
}

MTL::PrimitiveTopologyClass MetalUtil::translatePrimitiveTopologyClass(PrimitiveType type)
{
    switch (type)
    {
    case PrimitiveType::Point:
        return MTL::PrimitiveTopologyClassPoint;
    case PrimitiveType::Line:
        return MTL::PrimitiveTopologyClassLine;
    case PrimitiveType::Triangle:
        return MTL::PrimitiveTopologyClassTriangle;
    case PrimitiveType::Patch:
    default:
        return MTL::PrimitiveTopologyClassUnspecified;
    }
}

MTL::BlendFactor MetalUtil::translateBlendFactor(BlendFactor factor)
{
    switch (factor)
    {
    case BlendFactor::Zero:
        return MTL::BlendFactorZero;
    case BlendFactor::One:
        return MTL::BlendFactorOne;
    case BlendFactor::SrcColor:
        return MTL::BlendFactorSourceColor;
    case BlendFactor::InvSrcColor:
        return MTL::BlendFactorOneMinusSourceColor;
    case BlendFactor::SrcAlpha:
        return MTL::BlendFactorSourceAlpha;
    case BlendFactor::InvSrcAlpha:
        return MTL::BlendFactorOneMinusSourceAlpha;
    case BlendFactor::DestAlpha:
        return MTL::BlendFactorDestinationAlpha;
    case BlendFactor::InvDestAlpha:
        return MTL::BlendFactorOneMinusDestinationAlpha;
    case BlendFactor::DestColor:
        return MTL::BlendFactorDestinationColor;
    case BlendFactor::InvDestColor:
        return MTL::BlendFactorOneMinusDestinationColor;
    case BlendFactor::SrcAlphaSaturate:
        return MTL::BlendFactorSourceAlphaSaturated;
    case BlendFactor::BlendColor:
        return MTL::BlendFactorBlendColor;
    case BlendFactor::InvBlendColor:
        return MTL::BlendFactorOneMinusBlendColor;
    case BlendFactor::SecondarySrcColor:
        return MTL::BlendFactorSource1Color;
    case BlendFactor::InvSecondarySrcColor:
        return MTL::BlendFactorOneMinusSource1Color;
    case BlendFactor::SecondarySrcAlpha:
        return MTL::BlendFactorSource1Alpha;
    case BlendFactor::InvSecondarySrcAlpha:
        return MTL::BlendFactorOneMinusSource1Alpha;
    default:
        return MTL::BlendFactor(0);
    }
}

MTL::BlendOperation MetalUtil::translateBlendOperation(BlendOp op)
{
    switch (op)
    {
    case BlendOp::Add:
        return MTL::BlendOperationAdd;
    case BlendOp::Subtract:
        return MTL::BlendOperationSubtract;
    case BlendOp::ReverseSubtract:
        return MTL::BlendOperationReverseSubtract;
    case BlendOp::Min:
        return MTL::BlendOperationMin;
    case BlendOp::Max:
        return MTL::BlendOperationMax;
    default:
        return MTL::BlendOperation(0);
    }
}

MTL::ColorWriteMask MetalUtil::translateColorWriteMask(RenderTargetWriteMask::Type mask)
{
    MTL::ColorWriteMask result = MTL::ColorWriteMaskNone;
    if (mask & RenderTargetWriteMask::EnableRed)
        result |= MTL::ColorWriteMaskRed;
    if (mask & RenderTargetWriteMask::EnableGreen)
        result |= MTL::ColorWriteMaskGreen;
    if (mask & RenderTargetWriteMask::EnableBlue)
        result |= MTL::ColorWriteMaskBlue;
    if (mask & RenderTargetWriteMask::EnableAlpha)
        result |= MTL::ColorWriteMaskAlpha;
    return result;
}

MTL::Winding MetalUtil::translateWinding(FrontFaceMode mode)
{
    switch (mode)
    {
    case FrontFaceMode::CounterClockwise:
        return MTL::WindingCounterClockwise;
    case FrontFaceMode::Clockwise:
        return MTL::WindingClockwise;
    default:
        return MTL::Winding(0);
    }
}

MTL::CullMode MetalUtil::translateCullMode(CullMode mode)
{
    switch (mode)
    {
    case CullMode::None:
        return MTL::CullModeNone;
    case CullMode::Front:
        return MTL::CullModeFront;
    case CullMode::Back:
        return MTL::CullModeBack;
    default:
        return MTL::CullMode(0);
    }
}

MTL::TriangleFillMode MetalUtil::translateTriangleFillMode(FillMode mode)
{
    switch (mode)
    {
    case FillMode::Solid:
        return MTL::TriangleFillModeFill;
    case FillMode::Wireframe:
        return MTL::TriangleFillModeLines;
    default:
        return MTL::TriangleFillMode(0);
    }
}

} // namespace gfx