// Copyright 2019 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "media/gpu/windows/d3d11_texture_selector.h"

#include <d3d11.h>

#include "base/feature_list.h"
#include "media/base/media_log.h"
#include "media/base/media_switches.h"
#include "media/base/win/mf_helpers.h"
#include "media/gpu/windows/d3d11_copying_texture_wrapper.h"
#include "media/gpu/windows/d3d11_video_device_format_support.h"
#include "ui/gfx/geometry/size.h"

namespace media {

TextureSelector::TextureSelector(VideoPixelFormat pixfmt,
                                 DXGI_FORMAT output_dxgifmt,
                                 ComD3D11VideoDevice video_device,
                                 ComD3D11DeviceContext device_context,
                                 bool shared_image_use_shared_handle)
    : pixel_format_(pixfmt),
      output_dxgifmt_(output_dxgifmt),
      video_device_(std::move(video_device)),
      device_context_(std::move(device_context)),
      shared_image_use_shared_handle_(shared_image_use_shared_handle) {}

TextureSelector::~TextureSelector() = default;

bool SupportsZeroCopy(const gpu::GpuPreferences& preferences,
                      const gpu::GpuDriverBugWorkarounds& workarounds) {
  if (!preferences.enable_zero_copy_dxgi_video)
    return false;

  if (workarounds.disable_dxgi_zero_copy_video)
    return false;

  return true;
}

// static
std::unique_ptr<TextureSelector> TextureSelector::Create(
    const gpu::GpuPreferences& gpu_preferences,
    const gpu::GpuDriverBugWorkarounds& workarounds,
    DXGI_FORMAT decoder_output_format,
    TextureSelector::HDRMode hdr_output_mode,
    const FormatSupportChecker* format_checker,
    ComD3D11VideoDevice video_device,
    ComD3D11DeviceContext device_context,
    MediaLog* media_log,
    bool shared_image_use_shared_handle) {
  VideoPixelFormat output_pixel_format;
  DXGI_FORMAT output_dxgi_format;
  absl::optional<gfx::ColorSpace> output_color_space;

  bool needs_texture_copy = !SupportsZeroCopy(gpu_preferences, workarounds);

  auto supports_fmt = [format_checker](auto fmt) {
    return format_checker->CheckOutputFormatSupport(fmt);
  };
  // TODO(liberato): add other options here, like "copy to rgb" for NV12.
  switch (decoder_output_format) {
    case DXGI_FORMAT_NV12: {
      MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder producing NV12";
      if (!needs_texture_copy || supports_fmt(DXGI_FORMAT_NV12)) {
        output_pixel_format = PIXEL_FORMAT_NV12;
        output_dxgi_format = DXGI_FORMAT_NV12;
        // Leave |output_color_space| the same, since we'll bind either the
        // original or the copy. Downstream will handle it, either in the
        // shaders or in the overlay, if needed.
        output_color_space.reset();
        MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder: Selected NV12";
      } else if (supports_fmt(DXGI_FORMAT_B8G8R8A8_UNORM)) {
        output_pixel_format = PIXEL_FORMAT_ARGB;
        output_dxgi_format = DXGI_FORMAT_B8G8R8A8_UNORM;
        output_color_space.reset();
        MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder: Selected ARGB";
      } else {
        MEDIA_LOG(INFO, media_log) << "NV12 not supported";
        return nullptr;
      }
      break;
    }
    case DXGI_FORMAT_P010: {
      MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder producing P010";
      if (hdr_output_mode == HDRMode::kSDROnly &&
          supports_fmt(DXGI_FORMAT_B8G8R8A8_UNORM)) {
        output_dxgi_format = DXGI_FORMAT_B8G8R8A8_UNORM;
        output_pixel_format = PIXEL_FORMAT_ARGB;
        output_color_space = gfx::ColorSpace::CreateSRGB();
        MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder: Selected ARGB";
      } else if (!needs_texture_copy || supports_fmt(DXGI_FORMAT_P010)) {
        output_dxgi_format = DXGI_FORMAT_P010;
        output_pixel_format = PIXEL_FORMAT_P016LE;
        output_color_space.reset();
        MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder: Selected P010";
      } else if (supports_fmt(DXGI_FORMAT_R16G16B16A16_FLOAT)) {
        output_dxgi_format = DXGI_FORMAT_R16G16B16A16_FLOAT;
        output_pixel_format = PIXEL_FORMAT_RGBAF16;
        output_color_space = gfx::ColorSpace::CreateSCRGBLinear();
        MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder: Selected RGBAF16";
      } else if (supports_fmt(DXGI_FORMAT_R10G10B10A2_UNORM)) {
        output_dxgi_format = DXGI_FORMAT_R10G10B10A2_UNORM;
        output_pixel_format = PIXEL_FORMAT_XB30;
        output_color_space = gfx::ColorSpace::CreateHDR10();
        MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder: Selected XB30";
      } else {
        MEDIA_LOG(INFO, media_log) << "P010 not supported";
        return nullptr;
      }
      break;
    }
    default: {
      // TODO(tmathmeyer) support other profiles in the future.
      MEDIA_LOG(INFO, media_log)
          << "D3D11VideoDecoder does not support " << decoder_output_format;
      return nullptr;
    }
  }

  // If we're trying to produce an output texture that's different from what
  // the decoder is providing, then we need to copy it. If sharing decoder
  // textures is not allowed, then copy either way.
  needs_texture_copy |= (decoder_output_format != output_dxgi_format);

  MEDIA_LOG(INFO, media_log)
      << "D3D11VideoDecoder output color space: "
      << (output_color_space ? output_color_space->ToString()
                             : "(same as input)");

  if (needs_texture_copy) {
    MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder is copying textures";
    return std::make_unique<CopyTextureSelector>(
        output_pixel_format, decoder_output_format, output_dxgi_format,
        output_color_space, std::move(video_device), std::move(device_context),
        shared_image_use_shared_handle);
  } else {
    MEDIA_LOG(INFO, media_log) << "D3D11VideoDecoder is binding textures";
    // Binding can't change the color space. The consumer has to do it, if they
    // want to.
    DCHECK(!output_color_space);
    return std::make_unique<TextureSelector>(
        output_pixel_format, output_dxgi_format, std::move(video_device),
        std::move(device_context), shared_image_use_shared_handle);
  }
}

std::unique_ptr<Texture2DWrapper> TextureSelector::CreateTextureWrapper(
    ComD3D11Device device,
    gfx::Size size) {
  // TODO(liberato): If the output format is rgb, then create a pbuffer wrapper.
  return std::make_unique<DefaultTexture2DWrapper>(size, OutputDXGIFormat());
}

bool TextureSelector::DoesDecoderOutputUseSharedHandle() const {
  return shared_image_use_shared_handle_;
}

bool TextureSelector::WillCopyForTesting() const {
  return false;
}

CopyTextureSelector::CopyTextureSelector(
    VideoPixelFormat pixfmt,
    DXGI_FORMAT input_dxgifmt,
    DXGI_FORMAT output_dxgifmt,
    absl::optional<gfx::ColorSpace> output_color_space,
    ComD3D11VideoDevice video_device,
    ComD3D11DeviceContext device_context,
    bool shared_image_use_shared_handle)
    : TextureSelector(pixfmt,
                      output_dxgifmt,
                      std::move(video_device),
                      std::move(device_context),
                      shared_image_use_shared_handle),
      output_color_space_(std::move(output_color_space)),
      video_processor_proxy_(
          base::MakeRefCounted<VideoProcessorProxy>(this->video_device(),
                                                    this->device_context())) {}

CopyTextureSelector::~CopyTextureSelector() = default;

std::unique_ptr<Texture2DWrapper> CopyTextureSelector::CreateTextureWrapper(
    ComD3D11Device device,
    gfx::Size size) {
  D3D11_TEXTURE2D_DESC texture_desc = {};
  texture_desc.MipLevels = 1;
  texture_desc.ArraySize = 1;
  texture_desc.CPUAccessFlags = 0;
  texture_desc.Format = output_dxgifmt_;
  texture_desc.SampleDesc.Count = 1;
  texture_desc.Usage = D3D11_USAGE_DEFAULT;
  texture_desc.BindFlags =
      D3D11_BIND_SHADER_RESOURCE | D3D11_BIND_RENDER_TARGET;
  texture_desc.Width = size.width();
  texture_desc.Height = size.height();
  if (DoesSharedImageUseSharedHandle()) {
    texture_desc.MiscFlags = D3D11_RESOURCE_MISC_SHARED_NTHANDLE |
                             D3D11_RESOURCE_MISC_SHARED_KEYEDMUTEX;
  }

  ComD3D11Texture2D out_texture;
  if (FAILED(device->CreateTexture2D(&texture_desc, nullptr, &out_texture)))
    return nullptr;

  if (FAILED(
          SetDebugName(out_texture.Get(), "D3D11Decoder_CopyTextureSelector")))
    return nullptr;

  return std::make_unique<CopyingTexture2DWrapper>(
      size, std::make_unique<DefaultTexture2DWrapper>(size, OutputDXGIFormat()),
      video_processor_proxy_, out_texture, output_color_space_);
}

bool CopyTextureSelector::DoesDecoderOutputUseSharedHandle() const {
  return false;
}

bool CopyTextureSelector::WillCopyForTesting() const {
  return true;
}

}  // namespace media