// Copyright 2014 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 or at
// https://developers.google.com/open-source/licenses/bsd

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

#include "packager/app/fixed_key_encryption_flags.h"
#include "packager/app/libcrypto_threading.h"
#include "packager/app/mpd_flags.h"
#include "packager/app/muxer_flags.h"
#include "packager/app/packager_util.h"
#include "packager/app/stream_descriptor.h"
#include "packager/app/vlog_flags.h"
#include "packager/app/widevine_encryption_flags.h"
#include "packager/base/at_exit.h"
#include "packager/base/command_line.h"
#include "packager/base/logging.h"
#include "packager/base/stl_util.h"
#include "packager/base/strings/string_split.h"
#include "packager/base/strings/stringprintf.h"
#include "packager/base/threading/simple_thread.h"
#include "packager/base/time/clock.h"
#include "packager/media/base/container_names.h"
#include "packager/media/base/demuxer.h"
#include "packager/media/base/encryption_modes.h"
#include "packager/media/base/key_source.h"
#include "packager/media/base/muxer_options.h"
#include "packager/media/base/muxer_util.h"
#include "packager/media/event/mpd_notify_muxer_listener.h"
#include "packager/media/event/vod_media_info_dump_muxer_listener.h"
#include "packager/media/file/file.h"
#include "packager/media/formats/mp4/mp4_muxer.h"
#include "packager/media/formats/webm/webm_muxer.h"
#include "packager/mpd/base/dash_iop_mpd_notifier.h"
#include "packager/mpd/base/media_info.pb.h"
#include "packager/mpd/base/mpd_builder.h"
#include "packager/mpd/base/simple_mpd_notifier.h"
#include "packager/version/version.h"

DEFINE_bool(use_fake_clock_for_muxer,
            false,
            "Set to true to use a fake clock for muxer. With this flag set, "
            "creation time and modification time in outputs are set to 0. "
            "Should only be used for testing.");

namespace {
const char kUsage[] =
    "Packager driver program. Usage:\n\n"
    "%s [flags] <stream_descriptor> ...\n"
    "stream_descriptor consists of comma separated field_name/value pairs:\n"
    "field_name=value,[field_name=value,]...\n"
    "Supported field names are as follows:\n"
    "  - input (in): Required input/source media file path or network stream\n"
    "    URL.\n"
    "  - stream_selector (stream): Required field with value 'audio',\n"
    "    'video', or stream number (zero based).\n"
    "  - output (out): Required output file (single file) or initialization\n"
    "    file path (multiple file).\n"
    "  - segment_template (segment): Optional value which specifies the\n"
    "    naming  pattern for the segment files, and that the stream should be\n"
    "    split into multiple files. Its presence should be consistent across\n"
    "    streams.\n"
    "  - bandwidth (bw): Optional value which contains a user-specified\n"
    "    content bit rate for the stream, in bits/sec. If specified, this\n"
    "    value is propagated to the $Bandwidth$ template parameter for\n"
    "    segment names. If not specified, its value may be estimated.\n"
    "  - language (lang): Optional value which contains a user-specified\n"
    "    language tag. If specified, this value overrides any language\n"
    "    metadata in the input track.\n"
    "  - output_format (format): Optional value which specifies the format\n"
    "    of the output files (MP4 or WebM).  If not specified, it will be\n"
    "    derived from the file extension of the output file.\n";

const char kMediaInfoSuffix[] = ".media_info";

enum ExitStatus {
  kSuccess = 0,
  kArgumentValidationFailed,
  kPackagingFailed,
  kInternalError,
};

// TODO(rkuroiwa): Write TTML and WebVTT parser (demuxing) for a better check
// and for supporting live/segmenting (muxing).  With a demuxer and a muxer,
// CreateRemuxJobs() shouldn't treat text as a special case.
std::string DetermineTextFileFormat(const std::string& file) {
  std::string content;
  if (!edash_packager::media::File::ReadFileToString(file.c_str(), &content)) {
    LOG(ERROR) << "Failed to open file " << file
               << " to determine file format.";
    return "";
  }
  edash_packager::media::MediaContainerName container_name =
      edash_packager::media::DetermineContainer(
          reinterpret_cast<const uint8_t*>(content.data()), content.size());
  if (container_name == edash_packager::media::CONTAINER_WEBVTT) {
    return "vtt";
  } else if (container_name == edash_packager::media::CONTAINER_TTML) {
    return "ttml";
  }

  return "";
}

edash_packager::media::EncryptionMode GetEncryptionMode(
    const std::string& protection_scheme) {
  if (protection_scheme == "cenc") {
    return edash_packager::media::kEncryptionModeAesCtr;
  } else if (protection_scheme == "cbc1") {
    return edash_packager::media::kEncryptionModeAesCbc;
  } else {
    LOG(ERROR) << "Unknown protection scheme: " << protection_scheme;
    return edash_packager::media::kEncryptionModeUnknown;
  }
}

}  // namespace

namespace edash_packager {
namespace media {

// A fake clock that always return time 0 (epoch). Should only be used for
// testing.
class FakeClock : public base::Clock {
 public:
  base::Time Now() override { return base::Time(); }
};

// Demux, Mux(es) and worker thread used to remux a source file/stream.
class RemuxJob : public base::SimpleThread {
 public:
  RemuxJob(scoped_ptr<Demuxer> demuxer)
      : SimpleThread("RemuxJob"),
        demuxer_(demuxer.Pass()) {}

  ~RemuxJob() override {
    STLDeleteElements(&muxers_);
  }

  void AddMuxer(scoped_ptr<Muxer> mux) {
    muxers_.push_back(mux.release());
  }

  Demuxer* demuxer() { return demuxer_.get(); }
  Status status() { return status_; }

 private:
  void Run() override {
    DCHECK(demuxer_);
    status_ = demuxer_->Run();
  }

  scoped_ptr<Demuxer> demuxer_;
  std::vector<Muxer*> muxers_;
  Status status_;

  DISALLOW_COPY_AND_ASSIGN(RemuxJob);
};

bool StreamInfoToTextMediaInfo(const StreamDescriptor& stream_descriptor,
                               const MuxerOptions& stream_muxer_options,
                               MediaInfo* text_media_info) {
  const std::string& language = stream_descriptor.language;
  std::string format = DetermineTextFileFormat(stream_descriptor.input);
  if (format.empty()) {
    LOG(ERROR) << "Failed to determine the text file format for "
               << stream_descriptor.input;
    return false;
  }

  if (!File::Copy(stream_descriptor.input.c_str(),
                  stream_muxer_options.output_file_name.c_str())) {
    LOG(ERROR) << "Failed to copy the input file (" << stream_descriptor.input
               << ") to output file (" << stream_muxer_options.output_file_name
               << ").";
    return false;
  }

  text_media_info->set_media_file_name(stream_muxer_options.output_file_name);
  text_media_info->set_container_type(MediaInfo::CONTAINER_TEXT);

  if (stream_muxer_options.bandwidth != 0) {
    text_media_info->set_bandwidth(stream_muxer_options.bandwidth);
  } else {
    // Text files are usually small and since the input is one file; there's no
    // way for the player to do ranged requests. So set this value to something
    // reasonable.
    text_media_info->set_bandwidth(256);
  }

  MediaInfo::TextInfo* text_info = text_media_info->mutable_text_info();
  text_info->set_format(format);
  if (!language.empty())
    text_info->set_language(language);

  return true;
}

scoped_ptr<Muxer> CreateOutputMuxer(const MuxerOptions& options,
                                    MediaContainerName container) {
  if (container == CONTAINER_WEBM) {
    return scoped_ptr<Muxer>(new webm::WebMMuxer(options));
  } else {
    DCHECK_EQ(container, CONTAINER_MOV);
    return scoped_ptr<Muxer>(new mp4::MP4Muxer(options));
  }
}

bool CreateRemuxJobs(const StreamDescriptorList& stream_descriptors,
                     const MuxerOptions& muxer_options,
                     FakeClock* fake_clock,
                     KeySource* key_source,
                     MpdNotifier* mpd_notifier,
                     std::vector<RemuxJob*>* remux_jobs) {
  DCHECK(remux_jobs);

  std::string previous_input;
  for (StreamDescriptorList::const_iterator stream_iter =
           stream_descriptors.begin();
       stream_iter != stream_descriptors.end();
       ++stream_iter) {
    // Process stream descriptor.
    MuxerOptions stream_muxer_options(muxer_options);
    stream_muxer_options.output_file_name = stream_iter->output;
    if (!stream_iter->segment_template.empty()) {
      if (!ValidateSegmentTemplate(stream_iter->segment_template)) {
        LOG(ERROR) << "ERROR: segment template with '"
                   << stream_iter->segment_template << "' is invalid.";
        return false;
      }
      stream_muxer_options.segment_template = stream_iter->segment_template;
    }
    stream_muxer_options.bandwidth = stream_iter->bandwidth;

    // Handle text input.
    if (stream_iter->stream_selector == "text") {
      MediaInfo text_media_info;
      if (!StreamInfoToTextMediaInfo(*stream_iter, stream_muxer_options,
                                     &text_media_info)) {
        return false;
      }

      if (mpd_notifier) {
        uint32 unused;
        if (!mpd_notifier->NotifyNewContainer(text_media_info, &unused)) {
          LOG(ERROR) << "Failed to process text file " << stream_iter->input;
        } else {
          mpd_notifier->Flush();
        }
      } else if (FLAGS_output_media_info) {
        VodMediaInfoDumpMuxerListener::WriteMediaInfoToFile(
            text_media_info,
            stream_muxer_options.output_file_name + kMediaInfoSuffix);
      } else {
        NOTIMPLEMENTED()
            << "--mpd_output or --output_media_info flags are "
               "required for text output. Skipping manifest related output for "
            << stream_iter->input;
      }
      continue;
    }

    if (stream_iter->input != previous_input) {
      // New remux job needed. Create demux and job thread.
      scoped_ptr<Demuxer> demuxer(new Demuxer(stream_iter->input));
      if (FLAGS_enable_widevine_decryption ||
          FLAGS_enable_fixed_key_decryption) {
        scoped_ptr<KeySource> key_source(CreateDecryptionKeySource());
        if (!key_source)
          return false;
        demuxer->SetKeySource(key_source.Pass());
      }
      Status status = demuxer->Initialize();
      if (!status.ok()) {
        LOG(ERROR) << "Demuxer failed to initialize: " << status.ToString();
        return false;
      }
      if (FLAGS_dump_stream_info) {
        printf("\nFile \"%s\":\n", stream_iter->input.c_str());
        DumpStreamInfo(demuxer->streams());
        if (stream_iter->output.empty())
          continue;  // just need stream info.
      }
      remux_jobs->push_back(new RemuxJob(demuxer.Pass()));
      previous_input = stream_iter->input;
    }
    DCHECK(!remux_jobs->empty());

    MediaContainerName output_format = stream_iter->output_format;
    if (output_format == CONTAINER_UNKNOWN) {
      output_format =
          DetermineContainerFromFileName(stream_muxer_options.output_file_name);

      if (output_format == CONTAINER_UNKNOWN) {
        LOG(ERROR) << "Unable to determine output format for file "
                   << stream_muxer_options.output_file_name;
        return false;
      }
    }

    scoped_ptr<Muxer> muxer(
        CreateOutputMuxer(stream_muxer_options, output_format));
    if (FLAGS_use_fake_clock_for_muxer) muxer->set_clock(fake_clock);

    if (key_source) {
      muxer->SetKeySource(key_source,
                          FLAGS_max_sd_pixels,
                          FLAGS_clear_lead,
                          FLAGS_crypto_period_duration,
                          GetEncryptionMode(FLAGS_protection_scheme));
    }

    scoped_ptr<MuxerListener> muxer_listener;
    DCHECK(!(FLAGS_output_media_info && mpd_notifier));
    if (FLAGS_output_media_info) {
      const std::string output_media_info_file_name =
          stream_muxer_options.output_file_name + kMediaInfoSuffix;
      scoped_ptr<VodMediaInfoDumpMuxerListener>
          vod_media_info_dump_muxer_listener(
              new VodMediaInfoDumpMuxerListener(output_media_info_file_name));
      muxer_listener = vod_media_info_dump_muxer_listener.Pass();
    }
    if (mpd_notifier) {
      scoped_ptr<MpdNotifyMuxerListener> mpd_notify_muxer_listener(
          new MpdNotifyMuxerListener(mpd_notifier));
      muxer_listener = mpd_notify_muxer_listener.Pass();
    }

    if (muxer_listener)
      muxer->SetMuxerListener(muxer_listener.Pass());

    if (!AddStreamToMuxer(remux_jobs->back()->demuxer()->streams(),
                          stream_iter->stream_selector,
                          stream_iter->language,
                          muxer.get()))
      return false;
    remux_jobs->back()->AddMuxer(muxer.Pass());
  }

  return true;
}

Status RunRemuxJobs(const std::vector<RemuxJob*>& remux_jobs) {
  // Start the job threads.
  for (std::vector<RemuxJob*>::const_iterator job_iter = remux_jobs.begin();
       job_iter != remux_jobs.end();
       ++job_iter) {
    (*job_iter)->Start();
  }

  // Wait for all jobs to complete or an error occurs.
  Status status;
  bool all_joined;
  do {
    all_joined = true;
    for (std::vector<RemuxJob*>::const_iterator job_iter = remux_jobs.begin();
         job_iter != remux_jobs.end();
         ++job_iter) {
      if ((*job_iter)->HasBeenJoined()) {
        status = (*job_iter)->status();
        if (!status.ok())
          break;
      } else {
        all_joined = false;
        (*job_iter)->Join();
      }
    }
  } while (!all_joined && status.ok());

  return status;
}

bool RunPackager(const StreamDescriptorList& stream_descriptors) {
  EncryptionMode encryption_mode = GetEncryptionMode(FLAGS_protection_scheme);
  if (encryption_mode == kEncryptionModeUnknown)
    return false;
  if (encryption_mode == kEncryptionModeAesCbc && !FLAGS_iv.empty()) {
    if (FLAGS_iv.size() != 16) {
      LOG(ERROR) << "Iv size should be 16 bytes for CBC encryption mode.";
      return false;
    }
  }

  if (!AssignFlagsFromProfile())
    return false;

  if (FLAGS_output_media_info && !FLAGS_mpd_output.empty()) {
    NOTIMPLEMENTED() << "ERROR: --output_media_info and --mpd_output do not "
                        "work together.";
    return false;
  }
  if (FLAGS_output_media_info && !FLAGS_single_segment) {
    // TODO(rkuroiwa, kqyang): Support partial media info dump for live.
    NOTIMPLEMENTED() << "ERROR: --output_media_info is only supported if "
                        "--single_segment is true.";
    return false;
  }

  // Get basic muxer options.
  MuxerOptions muxer_options;
  if (!GetMuxerOptions(&muxer_options))
    return false;

  MpdOptions mpd_options;
  if (!GetMpdOptions(&mpd_options))
    return false;

  // Create encryption key source if needed.
  scoped_ptr<KeySource> encryption_key_source;
  if (FLAGS_enable_widevine_encryption || FLAGS_enable_fixed_key_encryption) {
    encryption_key_source = CreateEncryptionKeySource();
    if (!encryption_key_source)
      return false;
  }

  scoped_ptr<MpdNotifier> mpd_notifier;
  if (!FLAGS_mpd_output.empty()) {
    DashProfile profile =
        FLAGS_single_segment ? kOnDemandProfile : kLiveProfile;
    std::vector<std::string> base_urls;
    base::SplitString(FLAGS_base_urls, ',', &base_urls);
    if (FLAGS_generate_dash_if_iop_compliant_mpd) {
      mpd_notifier.reset(new DashIopMpdNotifier(profile, mpd_options, base_urls,
                                                FLAGS_mpd_output));
    } else {
      mpd_notifier.reset(new SimpleMpdNotifier(profile, mpd_options, base_urls,
                                               FLAGS_mpd_output));
    }
    if (!mpd_notifier->Init()) {
      LOG(ERROR) << "MpdNotifier failed to initialize.";
      return false;
    }
  }

  std::vector<RemuxJob*> remux_jobs;
  STLElementDeleter<std::vector<RemuxJob*> > scoped_jobs_deleter(&remux_jobs);
  FakeClock fake_clock;
  if (!CreateRemuxJobs(stream_descriptors, muxer_options, &fake_clock,
                       encryption_key_source.get(), mpd_notifier.get(),
                       &remux_jobs)) {
    return false;
  }

  Status status = RunRemuxJobs(remux_jobs);
  if (!status.ok()) {
    LOG(ERROR) << "Packaging Error: " << status.ToString();
    return false;
  }

  printf("Packaging completed successfully.\n");
  return true;
}

int PackagerMain(int argc, char** argv) {
  base::AtExitManager exit;
  // Needed to enable VLOG/DVLOG through --vmodule or --v.
  base::CommandLine::Init(argc, argv);
  CHECK(logging::InitLogging(logging::LoggingSettings()));

  google::SetUsageMessage(base::StringPrintf(kUsage, argv[0]));
  google::ParseCommandLineFlags(&argc, &argv, true);
  if (argc < 2) {
    std::string version_string =
        base::StringPrintf("edash-packager version %s", kPackagerVersion);
    google::ShowUsageWithFlags(version_string.c_str());
    return kSuccess;
  }

  if (!ValidateWidevineCryptoFlags() || !ValidateFixedCryptoFlags())
    return kArgumentValidationFailed;

  edash_packager::media::LibcryptoThreading libcrypto_threading;
  // TODO(tinskip): Make InsertStreamDescriptor a member of
  // StreamDescriptorList.
  StreamDescriptorList stream_descriptors;
  for (int i = 1; i < argc; ++i) {
    if (!InsertStreamDescriptor(argv[i], &stream_descriptors))
      return kArgumentValidationFailed;
  }
  return RunPackager(stream_descriptors) ? kSuccess : kPackagingFailed;
}

}  // namespace media
}  // namespace edash_packager

int main(int argc, char** argv) {
  return edash_packager::media::PackagerMain(argc, argv);
}