use winapi::shared::dxgiformat;

pub fn map_texture_format(format: wgt::TextureFormat) -> dxgiformat::DXGI_FORMAT {
    use wgt::TextureFormat as Tf;
    use winapi::shared::dxgiformat::*;

    match format {
        Tf::R8Unorm => DXGI_FORMAT_R8_UNORM,
        Tf::R8Snorm => DXGI_FORMAT_R8_SNORM,
        Tf::R8Uint => DXGI_FORMAT_R8_UINT,
        Tf::R8Sint => DXGI_FORMAT_R8_SINT,
        Tf::R16Uint => DXGI_FORMAT_R16_UINT,
        Tf::R16Sint => DXGI_FORMAT_R16_SINT,
        Tf::R16Unorm => DXGI_FORMAT_R16_UNORM,
        Tf::R16Snorm => DXGI_FORMAT_R16_SNORM,
        Tf::R16Float => DXGI_FORMAT_R16_FLOAT,
        Tf::Rg8Unorm => DXGI_FORMAT_R8G8_UNORM,
        Tf::Rg8Snorm => DXGI_FORMAT_R8G8_SNORM,
        Tf::Rg8Uint => DXGI_FORMAT_R8G8_UINT,
        Tf::Rg8Sint => DXGI_FORMAT_R8G8_SINT,
        Tf::Rg16Unorm => DXGI_FORMAT_R16G16_UNORM,
        Tf::Rg16Snorm => DXGI_FORMAT_R16G16_SNORM,
        Tf::R32Uint => DXGI_FORMAT_R32_UINT,
        Tf::R32Sint => DXGI_FORMAT_R32_SINT,
        Tf::R32Float => DXGI_FORMAT_R32_FLOAT,
        Tf::Rg16Uint => DXGI_FORMAT_R16G16_UINT,
        Tf::Rg16Sint => DXGI_FORMAT_R16G16_SINT,
        Tf::Rg16Float => DXGI_FORMAT_R16G16_FLOAT,
        Tf::Rgba8Unorm => DXGI_FORMAT_R8G8B8A8_UNORM,
        Tf::Rgba8UnormSrgb => DXGI_FORMAT_R8G8B8A8_UNORM_SRGB,
        Tf::Bgra8UnormSrgb => DXGI_FORMAT_B8G8R8A8_UNORM_SRGB,
        Tf::Rgba8Snorm => DXGI_FORMAT_R8G8B8A8_SNORM,
        Tf::Bgra8Unorm => DXGI_FORMAT_B8G8R8A8_UNORM,
        Tf::Rgba8Uint => DXGI_FORMAT_R8G8B8A8_UINT,
        Tf::Rgba8Sint => DXGI_FORMAT_R8G8B8A8_SINT,
        Tf::Rgb10a2Unorm => DXGI_FORMAT_R10G10B10A2_UNORM,
        Tf::Rg11b10Float => DXGI_FORMAT_R11G11B10_FLOAT,
        Tf::Rg32Uint => DXGI_FORMAT_R32G32_UINT,
        Tf::Rg32Sint => DXGI_FORMAT_R32G32_SINT,
        Tf::Rg32Float => DXGI_FORMAT_R32G32_FLOAT,
        Tf::Rgba16Uint => DXGI_FORMAT_R16G16B16A16_UINT,
        Tf::Rgba16Sint => DXGI_FORMAT_R16G16B16A16_SINT,
        Tf::Rgba16Unorm => DXGI_FORMAT_R16G16B16A16_UNORM,
        Tf::Rgba16Snorm => DXGI_FORMAT_R16G16B16A16_SNORM,
        Tf::Rgba16Float => DXGI_FORMAT_R16G16B16A16_FLOAT,
        Tf::Rgba32Uint => DXGI_FORMAT_R32G32B32A32_UINT,
        Tf::Rgba32Sint => DXGI_FORMAT_R32G32B32A32_SINT,
        Tf::Rgba32Float => DXGI_FORMAT_R32G32B32A32_FLOAT,
        Tf::Depth32Float => DXGI_FORMAT_D32_FLOAT,
        Tf::Depth32FloatStencil8 => DXGI_FORMAT_D32_FLOAT_S8X24_UINT,
        Tf::Depth24Plus => DXGI_FORMAT_D24_UNORM_S8_UINT,
        Tf::Depth24PlusStencil8 => DXGI_FORMAT_D24_UNORM_S8_UINT,
        Tf::Rgb9e5Ufloat => DXGI_FORMAT_R9G9B9E5_SHAREDEXP,
        Tf::Bc1RgbaUnorm => DXGI_FORMAT_BC1_UNORM,
        Tf::Bc1RgbaUnormSrgb => DXGI_FORMAT_BC1_UNORM_SRGB,
        Tf::Bc2RgbaUnorm => DXGI_FORMAT_BC2_UNORM,
        Tf::Bc2RgbaUnormSrgb => DXGI_FORMAT_BC2_UNORM_SRGB,
        Tf::Bc3RgbaUnorm => DXGI_FORMAT_BC3_UNORM,
        Tf::Bc3RgbaUnormSrgb => DXGI_FORMAT_BC3_UNORM_SRGB,
        Tf::Bc4RUnorm => DXGI_FORMAT_BC4_UNORM,
        Tf::Bc4RSnorm => DXGI_FORMAT_BC4_SNORM,
        Tf::Bc5RgUnorm => DXGI_FORMAT_BC5_UNORM,
        Tf::Bc5RgSnorm => DXGI_FORMAT_BC5_SNORM,
        Tf::Bc6hRgbUfloat => DXGI_FORMAT_BC6H_UF16,
        Tf::Bc6hRgbSfloat => DXGI_FORMAT_BC6H_SF16,
        Tf::Bc7RgbaUnorm => DXGI_FORMAT_BC7_UNORM,
        Tf::Bc7RgbaUnormSrgb => DXGI_FORMAT_BC7_UNORM_SRGB,
        Tf::Etc2Rgb8Unorm
        | Tf::Etc2Rgb8UnormSrgb
        | Tf::Etc2Rgb8A1Unorm
        | Tf::Etc2Rgb8A1UnormSrgb
        | Tf::Etc2Rgba8Unorm
        | Tf::Etc2Rgba8UnormSrgb
        | Tf::EacR11Unorm
        | Tf::EacR11Snorm
        | Tf::EacRg11Unorm
        | Tf::EacRg11Snorm
        | Tf::Astc {
            block: _,
            channel: _,
        } => unreachable!(),
    }
}

// Note: DXGI doesn't allow sRGB format on the swapchain,
// but creating RTV of swapchain buffers with sRGB works.
pub fn map_texture_format_nosrgb(format: wgt::TextureFormat) -> dxgiformat::DXGI_FORMAT {
    match format {
        wgt::TextureFormat::Bgra8UnormSrgb => dxgiformat::DXGI_FORMAT_B8G8R8A8_UNORM,
        wgt::TextureFormat::Rgba8UnormSrgb => dxgiformat::DXGI_FORMAT_R8G8B8A8_UNORM,
        _ => map_texture_format(format),
    }
}

//Note: SRV and UAV can't use the depth formats directly
//TODO: stencil views?
pub fn map_texture_format_nodepth(format: wgt::TextureFormat) -> dxgiformat::DXGI_FORMAT {
    match format {
        wgt::TextureFormat::Depth32Float => dxgiformat::DXGI_FORMAT_R32_FLOAT,
        wgt::TextureFormat::Depth32FloatStencil8 => {
            dxgiformat::DXGI_FORMAT_R32_FLOAT_X8X24_TYPELESS
        }
        wgt::TextureFormat::Depth24Plus | wgt::TextureFormat::Depth24PlusStencil8 => {
            dxgiformat::DXGI_FORMAT_R24_UNORM_X8_TYPELESS
        }
        _ => {
            assert_eq!(
                crate::FormatAspects::from(format),
                crate::FormatAspects::COLOR
            );
            map_texture_format(format)
        }
    }
}

pub fn map_texture_format_depth_typeless(format: wgt::TextureFormat) -> dxgiformat::DXGI_FORMAT {
    match format {
        wgt::TextureFormat::Depth32Float => dxgiformat::DXGI_FORMAT_R32_TYPELESS,
        wgt::TextureFormat::Depth32FloatStencil8 => dxgiformat::DXGI_FORMAT_R32G8X24_TYPELESS,
        wgt::TextureFormat::Depth24Plus | wgt::TextureFormat::Depth24PlusStencil8 => {
            dxgiformat::DXGI_FORMAT_R24G8_TYPELESS
        }
        _ => unreachable!(),
    }
}

pub fn map_index_format(format: wgt::IndexFormat) -> dxgiformat::DXGI_FORMAT {
    match format {
        wgt::IndexFormat::Uint16 => dxgiformat::DXGI_FORMAT_R16_UINT,
        wgt::IndexFormat::Uint32 => dxgiformat::DXGI_FORMAT_R32_UINT,
    }
}

pub fn map_vertex_format(format: wgt::VertexFormat) -> dxgiformat::DXGI_FORMAT {
    use wgt::VertexFormat as Vf;
    use winapi::shared::dxgiformat::*;

    match format {
        Vf::Unorm8x2 => DXGI_FORMAT_R8G8_UNORM,
        Vf::Snorm8x2 => DXGI_FORMAT_R8G8_SNORM,
        Vf::Uint8x2 => DXGI_FORMAT_R8G8_UINT,
        Vf::Sint8x2 => DXGI_FORMAT_R8G8_SINT,
        Vf::Unorm8x4 => DXGI_FORMAT_R8G8B8A8_UNORM,
        Vf::Snorm8x4 => DXGI_FORMAT_R8G8B8A8_SNORM,
        Vf::Uint8x4 => DXGI_FORMAT_R8G8B8A8_UINT,
        Vf::Sint8x4 => DXGI_FORMAT_R8G8B8A8_SINT,
        Vf::Unorm16x2 => DXGI_FORMAT_R16G16_UNORM,
        Vf::Snorm16x2 => DXGI_FORMAT_R16G16_SNORM,
        Vf::Uint16x2 => DXGI_FORMAT_R16G16_UINT,
        Vf::Sint16x2 => DXGI_FORMAT_R16G16_SINT,
        Vf::Float16x2 => DXGI_FORMAT_R16G16_FLOAT,
        Vf::Unorm16x4 => DXGI_FORMAT_R16G16B16A16_UNORM,
        Vf::Snorm16x4 => DXGI_FORMAT_R16G16B16A16_SNORM,
        Vf::Uint16x4 => DXGI_FORMAT_R16G16B16A16_UINT,
        Vf::Sint16x4 => DXGI_FORMAT_R16G16B16A16_SINT,
        Vf::Float16x4 => DXGI_FORMAT_R16G16B16A16_FLOAT,
        Vf::Uint32 => DXGI_FORMAT_R32_UINT,
        Vf::Sint32 => DXGI_FORMAT_R32_SINT,
        Vf::Float32 => DXGI_FORMAT_R32_FLOAT,
        Vf::Uint32x2 => DXGI_FORMAT_R32G32_UINT,
        Vf::Sint32x2 => DXGI_FORMAT_R32G32_SINT,
        Vf::Float32x2 => DXGI_FORMAT_R32G32_FLOAT,
        Vf::Uint32x3 => DXGI_FORMAT_R32G32B32_UINT,
        Vf::Sint32x3 => DXGI_FORMAT_R32G32B32_SINT,
        Vf::Float32x3 => DXGI_FORMAT_R32G32B32_FLOAT,
        Vf::Uint32x4 => DXGI_FORMAT_R32G32B32A32_UINT,
        Vf::Sint32x4 => DXGI_FORMAT_R32G32B32A32_SINT,
        Vf::Float32x4 => DXGI_FORMAT_R32G32B32A32_FLOAT,
        Vf::Float64 | Vf::Float64x2 | Vf::Float64x3 | Vf::Float64x4 => unimplemented!(),
    }
}

pub fn map_acomposite_alpha_mode(mode: crate::CompositeAlphaMode) -> native::AlphaMode {
    use crate::CompositeAlphaMode as Cam;
    match mode {
        Cam::Opaque => native::AlphaMode::Ignore,
        Cam::PreMultiplied => native::AlphaMode::Premultiplied,
        Cam::PostMultiplied => native::AlphaMode::Straight,
    }
}
