//! Cache implementations for D3D blob types that need to live
//! here because of the orphan rule.

use crate::{CacheKey, Cacheable};

impl CacheKey for windows::Win32::Graphics::Direct3D::ID3DBlob {
    fn hash_bytes(&self) -> &[u8] {
        unsafe { std::slice::from_raw_parts(self.GetBufferPointer().cast(), self.GetBufferSize()) }
    }
}

impl CacheKey for windows::Win32::Graphics::Direct3D::Dxc::IDxcBlob {
    fn hash_bytes(&self) -> &[u8] {
        unsafe { std::slice::from_raw_parts(self.GetBufferPointer().cast(), self.GetBufferSize()) }
    }
}

impl Cacheable for windows::Win32::Graphics::Direct3D::ID3DBlob {
    fn from_bytes(bytes: &[u8]) -> Option<Self> {
        let Some(blob) = (unsafe { windows::Win32::Graphics::Direct3D::Fxc::D3DCreateBlob(bytes.len()).ok() }) else {
            return None;
        };

        let slice = unsafe {
            std::slice::from_raw_parts_mut(blob.GetBufferPointer().cast(), blob.GetBufferSize())
        };

        slice.copy_from_slice(bytes);

        Some(blob)
    }

    fn to_bytes(&self) -> Option<Vec<u8>> {
        let slice = unsafe {
            std::slice::from_raw_parts(self.GetBufferPointer().cast(), self.GetBufferSize())
        };

        Some(Vec::from(slice))
    }
}

impl Cacheable for windows::Win32::Graphics::Direct3D::Dxc::IDxcBlob {
    fn from_bytes(bytes: &[u8]) -> Option<Self> {
        let Some(blob) = (unsafe {
            windows::Win32::Graphics::Direct3D::Dxc::DxcCreateInstance(
                &windows::Win32::Graphics::Direct3D::Dxc::CLSID_DxcLibrary)
                .and_then(|library: windows::Win32::Graphics::Direct3D::Dxc::IDxcUtils| {
                    library.CreateBlob(bytes.as_ptr().cast(), bytes.len() as u32,
                                       windows::Win32::Graphics::Direct3D::Dxc::DXC_CP(0))
                }).ok()
        }) else {
            return None;
        };

        Some(blob.into())
    }

    fn to_bytes(&self) -> Option<Vec<u8>> {
        let slice = unsafe {
            std::slice::from_raw_parts(self.GetBufferPointer().cast(), self.GetBufferSize())
        };

        Some(Vec::from(slice))
    }
}