// Copyright (c) 2013 Google Inc. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <gflags/gflags.h>
#include <iostream>

#include "app/fixed_key_encryption_flags.h"
#include "app/muxer_flags.h"
#include "app/widevine_encryption_flags.h"
#include "base/file_util.h"
#include "base/logging.h"
#include "base/strings/stringprintf.h"
#include "media/base/demuxer.h"
#include "media/base/fixed_encryptor_source.h"
#include "media/base/widevine_encryptor_source.h"
#include "media/base/media_stream.h"
#include "media/base/muxer_options.h"
#include "media/base/request_signer.h"
#include "media/base/stream_info.h"
#include "media/file/file.h"
#include "media/mp4/mp4_muxer.h"

DEFINE_bool(dump_stream_info, false, "Dump demuxed stream info.");

namespace {
const char kUsage[] =
    "Packager driver program. Sample Usage:\n%s <input> [flags]";
}  // namespace

namespace media {

void DumpStreamInfo(const std::vector<MediaStream*>& streams) {
  std::cout << "Found " << streams.size() << " stream(s)." << std::endl;
  for (size_t i = 0; i < streams.size(); ++i)
    std::cout << "Stream [" << i << "] " << streams[i]->ToString() << std::endl;
}

// Create and initialize encryptor source.
scoped_ptr<EncryptorSource> CreateEncryptorSource() {
  scoped_ptr<EncryptorSource> encryptor_source;
  if (FLAGS_enable_widevine_encryption) {
    std::string rsa_private_key;
    if (!File::ReadFileToString(FLAGS_signing_key_path.c_str(),
                                &rsa_private_key)) {
      LOG(ERROR) << "Failed to read from rsa_key_file.";
      return scoped_ptr<EncryptorSource>();
    }

    scoped_ptr<RequestSigner> signer(
        RsaRequestSigner::CreateSigner(FLAGS_signer, rsa_private_key));
    if (!signer) {
      LOG(ERROR) << "Cannot create signer object from "
                 << FLAGS_signing_key_path;
      return scoped_ptr<EncryptorSource>();
    }

    WidevineEncryptorSource::TrackType track_type =
        WidevineEncryptorSource::GetTrackTypeFromString(FLAGS_track_type);
    if (track_type == WidevineEncryptorSource::TRACK_TYPE_UNKNOWN) {
      LOG(ERROR) << "Unknown track_type specified.";
      return scoped_ptr<EncryptorSource>();
    }

    encryptor_source.reset(new WidevineEncryptorSource(
        FLAGS_server_url, FLAGS_content_id, track_type, signer.Pass()));
  } else if (FLAGS_enable_fixed_key_encryption) {
    encryptor_source.reset(
        new FixedEncryptorSource(FLAGS_key_id, FLAGS_key, FLAGS_pssh));
  }

  if (encryptor_source) {
    Status status = encryptor_source->Initialize();
    if (!status.ok()) {
      LOG(ERROR) << "Encryptor source failed to initialize: "
                 << status.ToString();
      return scoped_ptr<EncryptorSource>();
    }
  }
  return encryptor_source.Pass();
}

bool GetMuxerOptions(MuxerOptions* muxer_options) {
  DCHECK(muxer_options);

  muxer_options->single_segment = FLAGS_single_segment;
  muxer_options->segment_duration = FLAGS_segment_duration;
  muxer_options->fragment_duration = FLAGS_fragment_duration;
  muxer_options->segment_sap_aligned = FLAGS_segment_sap_aligned;
  muxer_options->fragment_sap_aligned = FLAGS_fragment_sap_aligned;
  muxer_options->num_subsegments_per_sidx = FLAGS_num_subsegments_per_sidx;
  muxer_options->output_file_name = FLAGS_output;
  muxer_options->segment_template = FLAGS_segment_template;
  muxer_options->temp_file_name = FLAGS_temp_file;

  // Create a temp file if needed.
  if (muxer_options->single_segment && muxer_options->temp_file_name.empty()) {
    base::FilePath path;
    if (!file_util::CreateTemporaryFile(&path)) {
      LOG(ERROR) << "Failed to create a temporary file.";
      return false;
    }
    muxer_options->temp_file_name = path.value();
  }
  return true;
}

MediaStream* FindFirstStreamOfType(const std::vector<MediaStream*>& streams,
                                   StreamType stream_type) {
  typedef std::vector<MediaStream*>::const_iterator StreamIterator;
  for (StreamIterator it = streams.begin(); it != streams.end(); ++it) {
    if ((*it)->info()->stream_type() == stream_type)
      return *it;
  }
  return NULL;
}
MediaStream* FindFirstVideoStream(const std::vector<MediaStream*>& streams) {
  return FindFirstStreamOfType(streams, kStreamVideo);
}
MediaStream* FindFirstAudioStream(const std::vector<MediaStream*>& streams) {
  return FindFirstStreamOfType(streams, kStreamAudio);
}

bool AddStreamToMuxer(const std::vector<MediaStream*>& streams, Muxer* muxer) {
  DCHECK(muxer);

  if (!FLAGS_video && !FLAGS_audio) {
    LOG(ERROR) << "Required: add_video_stream or add_audio_stream.";
    return false;
  }

  MediaStream* stream = FLAGS_video ? FindFirstVideoStream(streams)
                                    : FindFirstAudioStream(streams);
  if (!stream) {
    LOG(ERROR) << "Cannot find a " << (FLAGS_video ? "video" : "audio")
               << " stream to mux.";
    return false;
  }
  Status status = muxer->AddStream(stream);
  if (!status.ok()) {
    LOG(ERROR) << "Muxer failed to add stream: " << status.ToString();
    return false;
  }
  return true;
}

bool RunPackager(const std::string& input) {
  Status status;

  // Setup and initialize Demuxer.
  Demuxer demuxer(input, NULL);
  status = demuxer.Initialize();
  if (!status.ok()) {
    LOG(ERROR) << "Demuxer failed to initialize: " << status.ToString();
    return false;
  }

  if (FLAGS_dump_stream_info)
    DumpStreamInfo(demuxer.streams());

  if (FLAGS_output.empty()) {
    LOG(INFO) << "No output specified. Exiting.";
    return true;
  }

  // Setup muxer.
  MuxerOptions muxer_options;
  if (!GetMuxerOptions(&muxer_options))
    return false;

  scoped_ptr<Muxer> muxer(new mp4::MP4Muxer(muxer_options));
  if (!AddStreamToMuxer(demuxer.streams(), muxer.get()))
    return false;

  scoped_ptr<EncryptorSource> encryptor_source;
  if (FLAGS_enable_widevine_encryption || FLAGS_enable_fixed_key_encryption) {
    encryptor_source = CreateEncryptorSource();
    if (!encryptor_source)
      return false;
  }
  muxer->SetEncryptorSource(encryptor_source.get(), FLAGS_clear_lead);

  status = muxer->Initialize();
  if (!status.ok()) {
    LOG(ERROR) << "Muxer failed to initialize: " << status.ToString();
    return false;
  }

  // Start remuxing process.
  status = demuxer.Run();
  if (!status.ok()) {
    LOG(ERROR) << "Remuxing failed: " << status.ToString();
    return false;
  }
  status = muxer->Finalize();
  if (!status.ok()) {
    LOG(ERROR) << "Muxer failed to finalize: " << status.ToString();
    return false;
  }

  std::cout << "Packaging completed successfully." << std::endl;
  return true;
}

}  // namespace media

int main(int argc, char** argv) {
  google::SetUsageMessage(base::StringPrintf(kUsage, argv[0]));
  google::ParseCommandLineFlags(&argc, &argv, true);
  if (argc < 2) {
    google::ShowUsageWithFlags(argv[0]);
    return 1;
  }
  return media::RunPackager(argv[1]) ? 0 : 1;
}