// Copyright 2010 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <fstream>
#include <string>

#include "Common/FileUtil.h"
#include "Common/Logging/Log.h"
#include "Common/MsgHandler.h"
#include "Common/StringUtil.h"
#include "VideoBackends/D3D12/D3DBase.h"
#include "VideoBackends/D3D12/D3DShader.h"
#include "VideoCommon/VideoConfig.h"

namespace DX12
{
namespace D3D
{
bool CompileShader(const std::string& code, ID3DBlob** blob, const D3D_SHADER_MACRO* defines,
                   const std::string& shader_version_string)
{
  ID3D10Blob* shader_buffer = nullptr;
  ID3D10Blob* error_buffer = nullptr;

#if defined(_DEBUG) || defined(DEBUGFAST)
  UINT flags = D3DCOMPILE_ENABLE_BACKWARDS_COMPATIBILITY | D3DCOMPILE_DEBUG;
#else
  UINT flags = D3DCOMPILE_ENABLE_BACKWARDS_COMPATIBILITY | D3DCOMPILE_OPTIMIZATION_LEVEL3 |
               D3DCOMPILE_SKIP_VALIDATION;
#endif
  HRESULT hr = d3d_compile(code.c_str(), code.length(), nullptr, defines, nullptr, "main",
                           shader_version_string.data(), flags, 0, &shader_buffer, &error_buffer);

  if (error_buffer)
  {
    WARN_LOG(VIDEO, "Warning generated when compiling %s shader:\n%s\n",
             shader_version_string.c_str(),
             static_cast<const char*>(error_buffer->GetBufferPointer()));
  }

  if (FAILED(hr))
  {
    static int num_failures = 0;
    std::string filename =
        StringFromFormat("%sbad_%s_%04i.txt", File::GetUserPath(D_DUMP_IDX).c_str(),
                         shader_version_string.c_str(), num_failures++);
    std::ofstream file;
    OpenFStream(file, filename, std::ios_base::out);
    file << code;
    file << std::endl << "Errors:" << std::endl;
    file << static_cast<const char*>(error_buffer->GetBufferPointer());
    file.close();

    PanicAlert("Failed to compile shader: %s\nDebug info (%s):\n%s", filename.c_str(),
               shader_version_string.c_str(),
               static_cast<const char*>(error_buffer->GetBufferPointer()));

    *blob = nullptr;
    error_buffer->Release();
  }
  else
  {
    *blob = shader_buffer;
  }

  return SUCCEEDED(hr);
}

// code->bytecode
bool CompileVertexShader(const std::string& code, ID3DBlob** blob)
{
  return CompileShader(code, blob, nullptr, D3D::VertexShaderVersionString());
}

// code->bytecode
bool CompileGeometryShader(const std::string& code, ID3DBlob** blob,
                           const D3D_SHADER_MACRO* defines)
{
  return CompileShader(code, blob, defines, D3D::GeometryShaderVersionString());
}

// code->bytecode
bool CompilePixelShader(const std::string& code, ID3DBlob** blob, const D3D_SHADER_MACRO* defines)
{
  return CompileShader(code, blob, defines, D3D::PixelShaderVersionString());
}

}  // namespace

}  // namespace DX12