/*
 *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "webrtc/modules/video_coding/utility/ivf_file_writer.h"

#include "webrtc/base/checks.h"
#include "webrtc/base/logging.h"
#include "webrtc/modules/rtp_rtcp/source/byte_io.h"

namespace webrtc {

IvfFileWriter::IvfFileWriter(const std::string& file_name,
                             std::unique_ptr<FileWrapper> file,
                             VideoCodecType codec_type)
    : codec_type_(codec_type),
      num_frames_(0),
      width_(0),
      height_(0),
      last_timestamp_(-1),
      using_capture_timestamps_(false),
      file_name_(file_name),
      file_(std::move(file)) {}

IvfFileWriter::~IvfFileWriter() {
  Close();
}

const size_t kIvfHeaderSize = 32;

std::unique_ptr<IvfFileWriter> IvfFileWriter::Open(const std::string& file_name,
                                                   VideoCodecType codec_type) {
  std::unique_ptr<IvfFileWriter> file_writer;
  std::unique_ptr<FileWrapper> file(FileWrapper::Create());
  if (file->OpenFile(file_name.c_str(), false) != 0)
    return file_writer;

  file_writer.reset(new IvfFileWriter(
      file_name, std::unique_ptr<FileWrapper>(std::move(file)), codec_type));
  if (!file_writer->WriteHeader())
    file_writer.reset();

  return file_writer;
}

bool IvfFileWriter::WriteHeader() {
  if (file_->Rewind() != 0) {
    LOG(LS_WARNING) << "Unable to rewind output file " << file_name_;
    return false;
  }

  uint8_t ivf_header[kIvfHeaderSize] = {0};
  ivf_header[0] = 'D';
  ivf_header[1] = 'K';
  ivf_header[2] = 'I';
  ivf_header[3] = 'F';
  ByteWriter<uint16_t>::WriteLittleEndian(&ivf_header[4], 0);   // Version.
  ByteWriter<uint16_t>::WriteLittleEndian(&ivf_header[6], 32);  // Header size.

  switch (codec_type_) {
    case kVideoCodecVP8:
      ivf_header[8] = 'V';
      ivf_header[9] = 'P';
      ivf_header[10] = '8';
      ivf_header[11] = '0';
      break;
    case kVideoCodecVP9:
      ivf_header[8] = 'V';
      ivf_header[9] = 'P';
      ivf_header[10] = '9';
      ivf_header[11] = '0';
      break;
    case kVideoCodecH264:
      ivf_header[8] = 'H';
      ivf_header[9] = '2';
      ivf_header[10] = '6';
      ivf_header[11] = '4';
      break;
    default:
      LOG(LS_ERROR) << "Unknown CODEC type: " << codec_type_;
      return false;
  }

  ByteWriter<uint16_t>::WriteLittleEndian(&ivf_header[12], width_);
  ByteWriter<uint16_t>::WriteLittleEndian(&ivf_header[14], height_);
  // Render timestamps are in ms (1/1000 scale), while RTP timestamps use a
  // 90kHz clock.
  ByteWriter<uint32_t>::WriteLittleEndian(
      &ivf_header[16], using_capture_timestamps_ ? 1000 : 90000);
  ByteWriter<uint32_t>::WriteLittleEndian(&ivf_header[20], 1);
  ByteWriter<uint32_t>::WriteLittleEndian(&ivf_header[24],
                                          static_cast<uint32_t>(num_frames_));
  ByteWriter<uint32_t>::WriteLittleEndian(&ivf_header[28], 0);  // Reserved.

  if (!file_->Write(ivf_header, kIvfHeaderSize)) {
    LOG(LS_ERROR) << "Unable to write IVF header for file " << file_name_;
    return false;
  }

  return true;
}

bool IvfFileWriter::InitFromFirstFrame(const EncodedImage& encoded_image) {
  width_ = encoded_image._encodedWidth;
  height_ = encoded_image._encodedHeight;
  RTC_CHECK_GT(width_, 0);
  RTC_CHECK_GT(height_, 0);
  using_capture_timestamps_ = encoded_image._timeStamp == 0;

  if (!WriteHeader())
    return false;

  std::string codec_name;
  switch (codec_type_) {
    case kRtpVideoVp8:
      codec_name = "VP8";
      break;
    case kRtpVideoVp9:
      codec_name = "VP9";
      break;
    case kRtpVideoH264:
      codec_name = "H264";
      break;
    default:
      codec_name = "Unkown";
  }
  LOG(LS_WARNING) << "Created IVF file " << file_name_
                  << " for codec data of type " << codec_name
                  << " at resolution " << width_ << " x " << height_
                  << ", using " << (using_capture_timestamps_ ? "1" : "90")
                  << "kHz clock resolution.";
  return true;
}

bool IvfFileWriter::WriteFrame(const EncodedImage& encoded_image) {
  RTC_DCHECK(file_->Open());

  if (num_frames_ == 0 && !InitFromFirstFrame(encoded_image))
    return false;

  if ((encoded_image._encodedWidth > 0 || encoded_image._encodedHeight > 0) &&
      (encoded_image._encodedHeight != height_ ||
       encoded_image._encodedWidth != width_)) {
    LOG(LS_WARNING)
        << "Incomig frame has diffferent resolution then previous: (" << width_
        << "x" << height_ << ") -> (" << encoded_image._encodedWidth << "x"
        << encoded_image._encodedHeight << ")";
  }

  int64_t timestamp = using_capture_timestamps_
                          ? encoded_image.capture_time_ms_
                          : wrap_handler_.Unwrap(encoded_image._timeStamp);
  if (last_timestamp_ != -1 && timestamp <= last_timestamp_) {
    LOG(LS_WARNING) << "Timestamp no increasing: " << last_timestamp_ << " -> "
                    << timestamp;
  }
  last_timestamp_ = timestamp;

  const size_t kFrameHeaderSize = 12;
  uint8_t frame_header[kFrameHeaderSize] = {};
  ByteWriter<uint32_t>::WriteLittleEndian(
      &frame_header[0], static_cast<uint32_t>(encoded_image._length));
  ByteWriter<uint64_t>::WriteLittleEndian(&frame_header[4], timestamp);
  if (!file_->Write(frame_header, kFrameHeaderSize) ||
      !file_->Write(encoded_image._buffer, encoded_image._length)) {
    LOG(LS_ERROR) << "Unable to write frame to file " << file_name_;
    return false;
  }

  ++num_frames_;
  return true;
}

bool IvfFileWriter::Close() {
  if (!file_->Open())
    return false;

  if (num_frames_ == 0) {
    // No frame written to file, close and remove it entirely if possible.
    file_->CloseFile();
    if (remove(file_name_.c_str()) != 0)
      LOG(LS_WARNING) << "Failed to remove empty IVF file " << file_name_;

    return true;
  }

  return WriteHeader() && (file_->CloseFile() == 0);
}

}  // namespace webrtc