// 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/D3D/D3DBase.h"
#include "VideoBackends/D3D/D3DShader.h"
#include "VideoCommon/VideoConfig.h"

namespace DX11
{
namespace D3D
{
// bytecode->shader
ID3D11VertexShader* CreateVertexShaderFromByteCode(const void* bytecode, unsigned int len)
{
  ID3D11VertexShader* v_shader;
  HRESULT hr = D3D::device->CreateVertexShader(bytecode, len, nullptr, &v_shader);
  if (FAILED(hr))
    return nullptr;

  return v_shader;
}

// code->bytecode
bool CompileVertexShader(const std::string& code, D3DBlob** blob)
{
  ID3D10Blob* shaderBuffer = nullptr;
  ID3D10Blob* errorBuffer = nullptr;

#if defined(_DEBUG) || defined(DEBUGFAST)
  UINT flags = D3D10_SHADER_ENABLE_BACKWARDS_COMPATIBILITY | D3D10_SHADER_DEBUG;
#else
  UINT flags = D3D10_SHADER_ENABLE_BACKWARDS_COMPATIBILITY | D3D10_SHADER_OPTIMIZATION_LEVEL3 |
               D3D10_SHADER_SKIP_VALIDATION;
#endif
  HRESULT hr = PD3DCompile(code.c_str(), code.length(), nullptr, nullptr, nullptr, "main",
                           D3D::VertexShaderVersionString(), flags, 0, &shaderBuffer, &errorBuffer);
  if (errorBuffer)
  {
    INFO_LOG(VIDEO, "Vertex shader compiler messages:\n%s\n",
             (const char*)errorBuffer->GetBufferPointer());
  }

  if (FAILED(hr))
  {
    static int num_failures = 0;
    std::string filename = StringFromFormat("%sbad_vs_%04i.txt",
                                            File::GetUserPath(D_DUMP_IDX).c_str(), num_failures++);
    std::ofstream file;
    OpenFStream(file, filename, std::ios_base::out);
    file << code;
    file.close();

    PanicAlert("Failed to compile vertex shader: %s\nDebug info (%s):\n%s", filename.c_str(),
               D3D::VertexShaderVersionString(), (const char*)errorBuffer->GetBufferPointer());

    *blob = nullptr;
    errorBuffer->Release();
  }
  else
  {
    *blob = new D3DBlob(shaderBuffer);
    shaderBuffer->Release();
  }
  return SUCCEEDED(hr);
}

// bytecode->shader
ID3D11GeometryShader* CreateGeometryShaderFromByteCode(const void* bytecode, unsigned int len)
{
  ID3D11GeometryShader* g_shader;
  HRESULT hr = D3D::device->CreateGeometryShader(bytecode, len, nullptr, &g_shader);
  if (FAILED(hr))
    return nullptr;

  return g_shader;
}

// code->bytecode
bool CompileGeometryShader(const std::string& code, D3DBlob** blob,
                           const D3D_SHADER_MACRO* pDefines)
{
  ID3D10Blob* shaderBuffer = nullptr;
  ID3D10Blob* errorBuffer = nullptr;

#if defined(_DEBUG) || defined(DEBUGFAST)
  UINT flags = D3D10_SHADER_ENABLE_BACKWARDS_COMPATIBILITY | D3D10_SHADER_DEBUG;
#else
  UINT flags = D3D10_SHADER_ENABLE_BACKWARDS_COMPATIBILITY | D3D10_SHADER_OPTIMIZATION_LEVEL3 |
               D3D10_SHADER_SKIP_VALIDATION;
#endif
  HRESULT hr =
      PD3DCompile(code.c_str(), code.length(), nullptr, pDefines, nullptr, "main",
                  D3D::GeometryShaderVersionString(), flags, 0, &shaderBuffer, &errorBuffer);

  if (errorBuffer)
  {
    INFO_LOG(VIDEO, "Geometry shader compiler messages:\n%s\n",
             (const char*)errorBuffer->GetBufferPointer());
  }

  if (FAILED(hr))
  {
    static int num_failures = 0;
    std::string filename = StringFromFormat("%sbad_gs_%04i.txt",
                                            File::GetUserPath(D_DUMP_IDX).c_str(), num_failures++);
    std::ofstream file;
    OpenFStream(file, filename, std::ios_base::out);
    file << code;
    file.close();

    PanicAlert("Failed to compile geometry shader: %s\nDebug info (%s):\n%s", filename.c_str(),
               D3D::GeometryShaderVersionString(), (const char*)errorBuffer->GetBufferPointer());

    *blob = nullptr;
    errorBuffer->Release();
  }
  else
  {
    *blob = new D3DBlob(shaderBuffer);
    shaderBuffer->Release();
  }
  return SUCCEEDED(hr);
}

// bytecode->shader
ID3D11PixelShader* CreatePixelShaderFromByteCode(const void* bytecode, unsigned int len)
{
  ID3D11PixelShader* p_shader;
  HRESULT hr = D3D::device->CreatePixelShader(bytecode, len, nullptr, &p_shader);
  if (FAILED(hr))
  {
    PanicAlert("CreatePixelShaderFromByteCode failed at %s %d\n", __FILE__, __LINE__);
    p_shader = nullptr;
  }
  return p_shader;
}

// code->bytecode
bool CompilePixelShader(const std::string& code, D3DBlob** blob, const D3D_SHADER_MACRO* pDefines)
{
  ID3D10Blob* shaderBuffer = nullptr;
  ID3D10Blob* errorBuffer = nullptr;

#if defined(_DEBUG) || defined(DEBUGFAST)
  UINT flags = D3D10_SHADER_DEBUG;
#else
  UINT flags = D3D10_SHADER_OPTIMIZATION_LEVEL3;
#endif
  HRESULT hr = PD3DCompile(code.c_str(), code.length(), nullptr, pDefines, nullptr, "main",
                           D3D::PixelShaderVersionString(), flags, 0, &shaderBuffer, &errorBuffer);

  if (errorBuffer)
  {
    INFO_LOG(VIDEO, "Pixel shader compiler messages:\n%s",
             (const char*)errorBuffer->GetBufferPointer());
  }

  if (FAILED(hr))
  {
    static int num_failures = 0;
    std::string filename = StringFromFormat("%sbad_ps_%04i.txt",
                                            File::GetUserPath(D_DUMP_IDX).c_str(), num_failures++);
    std::ofstream file;
    OpenFStream(file, filename, std::ios_base::out);
    file << code;
    file.close();

    PanicAlert("Failed to compile pixel shader: %s\nDebug info (%s):\n%s", filename.c_str(),
               D3D::PixelShaderVersionString(), (const char*)errorBuffer->GetBufferPointer());

    *blob = nullptr;
    errorBuffer->Release();
  }
  else
  {
    *blob = new D3DBlob(shaderBuffer);
    shaderBuffer->Release();
  }

  return SUCCEEDED(hr);
}

ID3D11VertexShader* CompileAndCreateVertexShader(const std::string& code)
{
  D3DBlob* blob = nullptr;
  if (CompileVertexShader(code, &blob))
  {
    ID3D11VertexShader* v_shader = CreateVertexShaderFromByteCode(blob);
    blob->Release();
    return v_shader;
  }
  return nullptr;
}

ID3D11GeometryShader* CompileAndCreateGeometryShader(const std::string& code,
                                                     const D3D_SHADER_MACRO* pDefines)
{
  D3DBlob* blob = nullptr;
  if (CompileGeometryShader(code, &blob, pDefines))
  {
    ID3D11GeometryShader* g_shader = CreateGeometryShaderFromByteCode(blob);
    blob->Release();
    return g_shader;
  }
  return nullptr;
}

ID3D11PixelShader* CompileAndCreatePixelShader(const std::string& code)
{
  D3DBlob* blob = nullptr;
  CompilePixelShader(code, &blob);
  if (blob)
  {
    ID3D11PixelShader* p_shader = CreatePixelShaderFromByteCode(blob);
    blob->Release();
    return p_shader;
  }
  return nullptr;
}

}  // namespace

}  // namespace DX11
