dom/media/webm/WebMDemuxer.cpp
author Bryce Van Dyk <bvandyk@mozilla.com>
Tue, 15 Mar 2016 00:28:47 +1300
changeset 290546 7a8fb7e6f6f915ad87eba700b4f36ff0c0d5ecab
parent 288812 66a65bdec004abadac9f1611f4f17bc277831674
permissions -rw-r--r--
Bug 1232045 - WebMDemuxer handles resolution changes. r=jya Update the WebMDemuxer to detect changes in resolution. When it does so it changes the streamID so that we get a new decoder created to handle the resolution change. The demuxer will also update media info in these cases, so the new decoder has the correct information. The demuxer will only handle resolution changes on key frames, files that attempt changes other times are not considered valid at this stage. If a resolution change cannot be performed because nest_egg cannot read track info, or because the new resolution is invalid, a change will not take place. MozReview-Commit-ID: 1JKz3mGbEvi

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsError.h"
#include "MediaDecoderStateMachine.h"
#include "AbstractMediaDecoder.h"
#include "MediaResource.h"
#include "WebMDemuxer.h"
#include "WebMBufferedParser.h"
#include "gfx2DGlue.h"
#include "mozilla/Atomics.h"
#include "mozilla/Endian.h"
#include "mozilla/Preferences.h"
#include "mozilla/SharedThreadPool.h"
#include "MediaDataDemuxer.h"
#include "nsAutoRef.h"
#include "NesteggPacketHolder.h"
#include "XiphExtradata.h"
#include "prprf.h"           // leaving it for PR_vsnprintf()
#include "mozilla/Snprintf.h"

#include <algorithm>
#include <stdint.h>

#define VPX_DONT_DEFINE_STDINT_TYPES
#include "vpx/vp8dx.h"
#include "vpx/vpx_decoder.h"

#define WEBM_DEBUG(arg, ...) MOZ_LOG(gWebMDemuxerLog, mozilla::LogLevel::Debug, ("WebMDemuxer(%p)::%s: " arg, this, __func__, ##__VA_ARGS__))

namespace mozilla {

using namespace gfx;

LazyLogModule gWebMDemuxerLog("WebMDemuxer");
LazyLogModule gNesteggLog("Nestegg");

// How far ahead will we look when searching future keyframe. In microseconds.
// This value is based on what appears to be a reasonable value as most webm
// files encountered appear to have keyframes located < 4s.
#define MAX_LOOK_AHEAD 10000000

static Atomic<uint32_t> sStreamSourceID(0u);

// Functions for reading and seeking using WebMDemuxer required for
// nestegg_io. The 'user data' passed to these functions is the
// demuxer.
static int webmdemux_read(void* aBuffer, size_t aLength, void* aUserData)
{
  MOZ_ASSERT(aUserData);
  MOZ_ASSERT(aLength < UINT32_MAX);
  WebMDemuxer* demuxer = reinterpret_cast<WebMDemuxer*>(aUserData);
  uint32_t count = aLength;
  if (demuxer->IsMediaSource()) {
    int64_t length = demuxer->GetEndDataOffset();
    int64_t position = demuxer->GetResource()->Tell();
    MOZ_ASSERT(position <= demuxer->GetResource()->GetLength());
    MOZ_ASSERT(position <= length);
    if (length >= 0 && count + position > length) {
      count = length - position;
    }
    MOZ_ASSERT(count <= aLength);
  }
  uint32_t bytes = 0;
  nsresult rv =
    demuxer->GetResource()->Read(static_cast<char*>(aBuffer), count, &bytes);
  bool eof = bytes < aLength;
  return NS_FAILED(rv) ? -1 : eof ? 0 : 1;
}

static int webmdemux_seek(int64_t aOffset, int aWhence, void* aUserData)
{
  MOZ_ASSERT(aUserData);
  WebMDemuxer* demuxer = reinterpret_cast<WebMDemuxer*>(aUserData);
  nsresult rv = demuxer->GetResource()->Seek(aWhence, aOffset);
  return NS_SUCCEEDED(rv) ? 0 : -1;
}

static int64_t webmdemux_tell(void* aUserData)
{
  MOZ_ASSERT(aUserData);
  WebMDemuxer* demuxer = reinterpret_cast<WebMDemuxer*>(aUserData);
  return demuxer->GetResource()->Tell();
}

static void webmdemux_log(nestegg* aContext,
                          unsigned int aSeverity,
                          char const* aFormat, ...)
{
  if (!MOZ_LOG_TEST(gNesteggLog, LogLevel::Debug)) {
    return;
  }

  va_list args;
  char msg[256];
  const char* sevStr;

  switch(aSeverity) {
    case NESTEGG_LOG_DEBUG:
      sevStr = "DBG";
      break;
    case NESTEGG_LOG_INFO:
      sevStr = "INF";
      break;
    case NESTEGG_LOG_WARNING:
      sevStr = "WRN";
      break;
    case NESTEGG_LOG_ERROR:
      sevStr = "ERR";
      break;
    case NESTEGG_LOG_CRITICAL:
      sevStr = "CRT";
      break;
    default:
      sevStr = "UNK";
      break;
  }

  va_start(args, aFormat);

  snprintf_literal(msg, "%p [Nestegg-%s] ", aContext, sevStr);
  PR_vsnprintf(msg+strlen(msg), sizeof(msg)-strlen(msg), aFormat, args);
  MOZ_LOG(gNesteggLog, LogLevel::Debug, (msg));

  va_end(args);
}


WebMDemuxer::WebMDemuxer(MediaResource* aResource)
  : WebMDemuxer(aResource, false)
{
}

WebMDemuxer::WebMDemuxer(MediaResource* aResource, bool aIsMediaSource)
  : mResource(aResource)
  , mBufferedState(nullptr)
  , mInitData(nullptr)
  , mContext(nullptr)
  , mVideoTrack(0)
  , mAudioTrack(0)
  , mSeekPreroll(0)
  , mAudioCodec(-1)
  , mVideoCodec(-1)
  , mHasVideo(false)
  , mHasAudio(false)
  , mNeedReIndex(true)
  , mLastWebMBlockOffset(-1)
  , mIsMediaSource(aIsMediaSource)
{
}

WebMDemuxer::~WebMDemuxer()
{
  Reset();
  Cleanup();
}

RefPtr<WebMDemuxer::InitPromise>
WebMDemuxer::Init()
{
  InitBufferedState();

  if (NS_FAILED(ReadMetadata())) {
    return InitPromise::CreateAndReject(DemuxerFailureReason::DEMUXER_ERROR, __func__);
  }

  if (!GetNumberTracks(TrackInfo::kAudioTrack) &&
      !GetNumberTracks(TrackInfo::kVideoTrack)) {
    return InitPromise::CreateAndReject(DemuxerFailureReason::DEMUXER_ERROR, __func__);
  }

  return InitPromise::CreateAndResolve(NS_OK, __func__);
}

void
WebMDemuxer::InitBufferedState()
{
  MOZ_ASSERT(!mBufferedState);
  mBufferedState = new WebMBufferedState;
}

bool
WebMDemuxer::HasTrackType(TrackInfo::TrackType aType) const
{
  return !!GetNumberTracks(aType);
}

uint32_t
WebMDemuxer::GetNumberTracks(TrackInfo::TrackType aType) const
{
  switch(aType) {
    case TrackInfo::kAudioTrack:
      return mHasAudio ? 1 : 0;
    case TrackInfo::kVideoTrack:
      return mHasVideo ? 1 : 0;
    default:
      return 0;
  }
}

UniquePtr<TrackInfo>
WebMDemuxer::GetTrackInfo(TrackInfo::TrackType aType,
                          size_t aTrackNumber) const
{
  switch(aType) {
    case TrackInfo::kAudioTrack:
      return mInfo.mAudio.Clone();
    case TrackInfo::kVideoTrack:
      return mInfo.mVideo.Clone();
    default:
      return nullptr;
  }
}

already_AddRefed<MediaTrackDemuxer>
WebMDemuxer::GetTrackDemuxer(TrackInfo::TrackType aType, uint32_t aTrackNumber)
{
  if (GetNumberTracks(aType) <= aTrackNumber) {
    return nullptr;
  }
  RefPtr<WebMTrackDemuxer> e =
    new WebMTrackDemuxer(this, aType, aTrackNumber);
  mDemuxers.AppendElement(e);

  return e.forget();
}

nsresult
WebMDemuxer::Reset()
{
  mVideoPackets.Reset();
  mAudioPackets.Reset();
  return NS_OK;
}

void
WebMDemuxer::Cleanup()
{
  if (mContext) {
    nestegg_destroy(mContext);
    mContext = nullptr;
  }
  mBufferedState = nullptr;
}

nsresult
WebMDemuxer::ReadMetadata()
{
  nestegg_io io;
  io.read = webmdemux_read;
  io.seek = webmdemux_seek;
  io.tell = webmdemux_tell;
  io.userdata = this;
  int r = nestegg_init(&mContext, io, &webmdemux_log,
                       IsMediaSource() ? mResource.GetLength() : -1);
  if (r == -1) {
    return NS_ERROR_FAILURE;
  }
  {
    // Check how much data nestegg read and force feed it to BufferedState.
    RefPtr<MediaByteBuffer> buffer = mResource.MediaReadAt(0, mResource.Tell());
    if (!buffer) {
      return NS_ERROR_FAILURE;
    }
    mBufferedState->NotifyDataArrived(buffer->Elements(), buffer->Length(), 0);
    if (mBufferedState->GetInitEndOffset() < 0) {
      return NS_ERROR_FAILURE;
    }
    MOZ_ASSERT(mBufferedState->GetInitEndOffset() <= mResource.Tell());
  }
  mInitData = mResource.MediaReadAt(0, mBufferedState->GetInitEndOffset());
  if (!mInitData ||
      mInitData->Length() != size_t(mBufferedState->GetInitEndOffset())) {
    return NS_ERROR_FAILURE;
  }

  unsigned int ntracks = 0;
  r = nestegg_track_count(mContext, &ntracks);
  if (r == -1) {
    return NS_ERROR_FAILURE;
  }

  for (unsigned int track = 0; track < ntracks; ++track) {
    int id = nestegg_track_codec_id(mContext, track);
    if (id == -1) {
      return NS_ERROR_FAILURE;
    }
    int type = nestegg_track_type(mContext, track);
    if (type == NESTEGG_TRACK_VIDEO && !mHasVideo) {
      nestegg_video_params params;
      r = nestegg_track_video_params(mContext, track, &params);
      if (r == -1) {
        return NS_ERROR_FAILURE;
      }
      mVideoCodec = nestegg_track_codec_id(mContext, track);
      switch(mVideoCodec) {
        case NESTEGG_CODEC_VP8:
          mInfo.mVideo.mMimeType = "video/webm; codecs=vp8";
          break;
        case NESTEGG_CODEC_VP9:
          mInfo.mVideo.mMimeType = "video/webm; codecs=vp9";
          break;
        default:
          NS_WARNING("Unknown WebM video codec");
          return NS_ERROR_FAILURE;
      }
      // Picture region, taking into account cropping, before scaling
      // to the display size.
      unsigned int cropH = params.crop_right + params.crop_left;
      unsigned int cropV = params.crop_bottom + params.crop_top;
      nsIntRect pictureRect(params.crop_left,
                            params.crop_top,
                            params.width - cropH,
                            params.height - cropV);

      // If the cropping data appears invalid then use the frame data
      if (pictureRect.width <= 0 ||
          pictureRect.height <= 0 ||
          pictureRect.x < 0 ||
          pictureRect.y < 0) {
        pictureRect.x = 0;
        pictureRect.y = 0;
        pictureRect.width = params.width;
        pictureRect.height = params.height;
      }

      // Validate the container-reported frame and pictureRect sizes. This
      // ensures that our video frame creation code doesn't overflow.
      nsIntSize displaySize(params.display_width, params.display_height);
      nsIntSize frameSize(params.width, params.height);
      if (!IsValidVideoRegion(frameSize, pictureRect, displaySize)) {
        // Video track's frame sizes will overflow. Ignore the video track.
        continue;
      }

      mVideoTrack = track;
      mHasVideo = true;

      mInfo.mVideo.mDisplay = displaySize;
      mInfo.mVideo.mImage = pictureRect;

      switch (params.stereo_mode) {
        case NESTEGG_VIDEO_MONO:
          mInfo.mVideo.mStereoMode = StereoMode::MONO;
          break;
        case NESTEGG_VIDEO_STEREO_LEFT_RIGHT:
          mInfo.mVideo.mStereoMode = StereoMode::LEFT_RIGHT;
          break;
        case NESTEGG_VIDEO_STEREO_BOTTOM_TOP:
          mInfo.mVideo.mStereoMode = StereoMode::BOTTOM_TOP;
          break;
        case NESTEGG_VIDEO_STEREO_TOP_BOTTOM:
          mInfo.mVideo.mStereoMode = StereoMode::TOP_BOTTOM;
          break;
        case NESTEGG_VIDEO_STEREO_RIGHT_LEFT:
          mInfo.mVideo.mStereoMode = StereoMode::RIGHT_LEFT;
          break;
      }
      uint64_t duration = 0;
      r = nestegg_duration(mContext, &duration);
      if (!r) {
        mInfo.mVideo.mDuration = media::TimeUnit::FromNanoseconds(duration).ToMicroseconds();
      }
    } else if (type == NESTEGG_TRACK_AUDIO && !mHasAudio) {
      nestegg_audio_params params;
      r = nestegg_track_audio_params(mContext, track, &params);
      if (r == -1) {
        return NS_ERROR_FAILURE;
      }

      mAudioTrack = track;
      mHasAudio = true;
      mCodecDelay = media::TimeUnit::FromNanoseconds(params.codec_delay).ToMicroseconds();
      mAudioCodec = nestegg_track_codec_id(mContext, track);
      if (mAudioCodec == NESTEGG_CODEC_VORBIS) {
        mInfo.mAudio.mMimeType = "audio/webm; codecs=vorbis";
      } else if (mAudioCodec == NESTEGG_CODEC_OPUS) {
        mInfo.mAudio.mMimeType = "audio/webm; codecs=opus";
        uint8_t c[sizeof(uint64_t)];
        BigEndian::writeUint64(&c[0], mCodecDelay);
        mInfo.mAudio.mCodecSpecificConfig->AppendElements(&c[0], sizeof(uint64_t));
      }
      mSeekPreroll = params.seek_preroll;
      mInfo.mAudio.mRate = params.rate;
      mInfo.mAudio.mChannels = params.channels;

      unsigned int nheaders = 0;
      r = nestegg_track_codec_data_count(mContext, track, &nheaders);
      if (r == -1) {
        return NS_ERROR_FAILURE;
      }

      AutoTArray<const unsigned char*,4> headers;
      AutoTArray<size_t,4> headerLens;
      for (uint32_t header = 0; header < nheaders; ++header) {
        unsigned char* data = 0;
        size_t length = 0;
        r = nestegg_track_codec_data(mContext, track, header, &data, &length);
        if (r == -1) {
          return NS_ERROR_FAILURE;
        }
        headers.AppendElement(data);
        headerLens.AppendElement(length);
      }

      // Vorbis has 3 headers, convert to Xiph extradata format to send them to
      // the demuxer.
      // TODO: This is already the format WebM stores them in. Would be nice
      // to avoid having libnestegg split them only for us to pack them again,
      // but libnestegg does not give us an API to access this data directly.
      if (nheaders > 1) {
        if (!XiphHeadersToExtradata(mInfo.mAudio.mCodecSpecificConfig,
                                    headers, headerLens)) {
          return NS_ERROR_FAILURE;
        }
      }
      else {
        mInfo.mAudio.mCodecSpecificConfig->AppendElements(headers[0],
                                                          headerLens[0]);
      }
      uint64_t duration = 0;
      r = nestegg_duration(mContext, &duration);
      if (!r) {
        mInfo.mAudio.mDuration = media::TimeUnit::FromNanoseconds(duration).ToMicroseconds();
      }
    }
  }
  return NS_OK;
}

bool
WebMDemuxer::IsSeekable() const
{
  return mContext && nestegg_has_cues(mContext);
}

bool
WebMDemuxer::IsSeekableOnlyInBufferedRanges() const
{
  return mContext && !nestegg_has_cues(mContext);
}

void
WebMDemuxer::EnsureUpToDateIndex()
{
  if (!mNeedReIndex || !mInitData) {
    return;
  }
  AutoPinned<MediaResource> resource(mResource.GetResource());
  MediaByteRangeSet byteRanges;
  nsresult rv = resource->GetCachedRanges(byteRanges);
  if (NS_FAILED(rv) || !byteRanges.Length()) {
    return;
  }
  mBufferedState->UpdateIndex(byteRanges, resource);

  mNeedReIndex = false;

  if (!mIsMediaSource) {
    return;
  }
  mLastWebMBlockOffset = mBufferedState->GetLastBlockOffset();
  MOZ_ASSERT(mLastWebMBlockOffset <= mResource.GetLength());
}

void
WebMDemuxer::NotifyDataArrived()
{
  WEBM_DEBUG("");
  mNeedReIndex = true;
}

void
WebMDemuxer::NotifyDataRemoved()
{
  mBufferedState->Reset();
  if (mInitData) {
    mBufferedState->NotifyDataArrived(mInitData->Elements(), mInitData->Length(), 0);
  }
  mNeedReIndex = true;
}

UniquePtr<EncryptionInfo>
WebMDemuxer::GetCrypto()
{
  return nullptr;
}

bool
WebMDemuxer::GetNextPacket(TrackInfo::TrackType aType, MediaRawDataQueue *aSamples)
{
  if (mIsMediaSource) {
    // To ensure mLastWebMBlockOffset is properly up to date.
    EnsureUpToDateIndex();
  }

  RefPtr<NesteggPacketHolder> holder(NextPacket(aType));

  if (!holder) {
    return false;
  }

  int r = 0;
  unsigned int count = 0;
  r = nestegg_packet_count(holder->Packet(), &count);
  if (r == -1) {
    return false;
  }
  int64_t tstamp = holder->Timestamp();

  // The end time of this frame is the start time of the next frame.  Fetch
  // the timestamp of the next packet for this track.  If we've reached the
  // end of the resource, use the file's duration as the end time of this
  // video frame.
  int64_t next_tstamp = INT64_MIN;
  if (aType == TrackInfo::kAudioTrack) {
    RefPtr<NesteggPacketHolder> next_holder(NextPacket(aType));
    if (next_holder) {
      next_tstamp = next_holder->Timestamp();
      PushAudioPacket(next_holder);
    } else if (!mIsMediaSource ||
               (mIsMediaSource && mLastAudioFrameTime.isSome())) {
      next_tstamp = tstamp;
      next_tstamp += tstamp - mLastAudioFrameTime.refOr(0);
    } else {
      PushAudioPacket(holder);
    }
    mLastAudioFrameTime = Some(tstamp);
  } else if (aType == TrackInfo::kVideoTrack) {
    RefPtr<NesteggPacketHolder> next_holder(NextPacket(aType));
    if (next_holder) {
      next_tstamp = next_holder->Timestamp();
      PushVideoPacket(next_holder);
    } else if (!mIsMediaSource ||
               (mIsMediaSource && mLastVideoFrameTime.isSome())) {
      next_tstamp = tstamp;
      next_tstamp += tstamp - mLastVideoFrameTime.refOr(0);
    } else {
      PushVideoPacket(holder);
    }
    mLastVideoFrameTime = Some(tstamp);
  }

  if (mIsMediaSource && next_tstamp == INT64_MIN) {
    return false;
  }

  int64_t discardPadding = 0;
  (void) nestegg_packet_discard_padding(holder->Packet(), &discardPadding);

  for (uint32_t i = 0; i < count; ++i) {
    unsigned char* data;
    size_t length;
    r = nestegg_packet_data(holder->Packet(), i, &data, &length);
    if (r == -1) {
      WEBM_DEBUG("nestegg_packet_data failed r=%d", r);
      return false;
    }
    bool isKeyframe = false;
    if (aType == TrackInfo::kAudioTrack) {
      isKeyframe = true;
    } else if (aType == TrackInfo::kVideoTrack) {
      vpx_codec_stream_info_t si;
      PodZero(&si);
      si.sz = sizeof(si);
      switch (mVideoCodec) {
        case NESTEGG_CODEC_VP8:
          vpx_codec_peek_stream_info(vpx_codec_vp8_dx(), data, length, &si);
          break;
        case NESTEGG_CODEC_VP9:
          vpx_codec_peek_stream_info(vpx_codec_vp9_dx(), data, length, &si);
          break;
      }
      isKeyframe = si.is_kf;
      if (isKeyframe) {
        // We only look for resolution changes on keyframes for both VP8 and
        // VP9. Other resolution changes are invalid.
        if (mLastSeenFrameWidth.isSome() && mLastSeenFrameHeight.isSome() &&
            (si.w != mLastSeenFrameWidth.value() ||
             si.h != mLastSeenFrameHeight.value())) {
          // We ignore cropping information on resizes during streams.
          // Cropping alone is rare, and we do not consider cropping to
          // still be valid after a resolution change
          mInfo.mVideo.mDisplay = nsIntSize(si.w, si.h);
          mInfo.mVideo.mImage = nsIntRect(0, 0, si.w, si.h);
          mSharedVideoTrackInfo = new SharedTrackInfo(mInfo.mVideo, ++sStreamSourceID);
        }
        mLastSeenFrameWidth = Some(si.w);
        mLastSeenFrameHeight = Some(si.h);
      }
    }

    WEBM_DEBUG("push sample tstamp: %ld next_tstamp: %ld length: %ld kf: %d",
               tstamp, next_tstamp, length, isKeyframe);
    RefPtr<MediaRawData> sample = new MediaRawData(data, length);
    sample->mTimecode = tstamp;
    sample->mTime = tstamp;
    sample->mDuration = next_tstamp - tstamp;
    sample->mOffset = holder->Offset();
    sample->mKeyframe = isKeyframe;
    if (discardPadding && i == count - 1) {
      uint8_t c[8];
      BigEndian::writeInt64(&c[0], discardPadding);
      sample->mExtraData = new MediaByteBuffer;
      sample->mExtraData->AppendElements(&c[0], 8);
    }
    if (aType == TrackInfo::kVideoTrack) {
      sample->mTrackInfo = mSharedVideoTrackInfo;
    }
    aSamples->Push(sample);
  }
  return true;
}

RefPtr<NesteggPacketHolder>
WebMDemuxer::NextPacket(TrackInfo::TrackType aType)
{
  bool isVideo = aType == TrackInfo::kVideoTrack;

  // The packet queue that packets will be pushed on if they
  // are not the type we are interested in.
  WebMPacketQueue& otherPackets = isVideo ? mAudioPackets : mVideoPackets;

  // The packet queue for the type that we are interested in.
  WebMPacketQueue &packets = isVideo ? mVideoPackets : mAudioPackets;

  // Flag to indicate that we do need to playback these types of
  // packets.
  bool hasType = isVideo ? mHasVideo : mHasAudio;

  // Flag to indicate that we do need to playback the other type
  // of track.
  bool hasOtherType = isVideo ? mHasAudio : mHasVideo;

  // Track we are interested in
  uint32_t ourTrack = isVideo ? mVideoTrack : mAudioTrack;

  // Value of other track
  uint32_t otherTrack = isVideo ? mAudioTrack : mVideoTrack;

  if (packets.GetSize() > 0) {
    return packets.PopFront();
  }

  do {
    RefPtr<NesteggPacketHolder> holder = DemuxPacket();
    if (!holder) {
      return nullptr;
    }

    if (hasOtherType && otherTrack == holder->Track()) {
      // Save the packet for when we want these packets
      otherPackets.Push(holder);
      continue;
    }

    // The packet is for the track we want to play
    if (hasType && ourTrack == holder->Track()) {
      return holder;
    }
  } while (true);
}

RefPtr<NesteggPacketHolder>
WebMDemuxer::DemuxPacket()
{
  nestegg_packet* packet;
  int r = nestegg_read_packet(mContext, &packet);
  if (r <= 0) {
    return nullptr;
  }

  unsigned int track = 0;
  r = nestegg_packet_track(packet, &track);
  if (r == -1) {
    return nullptr;
  }

  int64_t offset = mResource.Tell();
  RefPtr<NesteggPacketHolder> holder = new NesteggPacketHolder();
  if (!holder->Init(packet, offset, track, false)) {
    return nullptr;
  }

  return holder;
}

void
WebMDemuxer::PushAudioPacket(NesteggPacketHolder* aItem)
{
  mAudioPackets.PushFront(aItem);
}

void
WebMDemuxer::PushVideoPacket(NesteggPacketHolder* aItem)
{
  mVideoPackets.PushFront(aItem);
}

nsresult
WebMDemuxer::SeekInternal(const media::TimeUnit& aTarget)
{
  EnsureUpToDateIndex();
  uint32_t trackToSeek = mHasVideo ? mVideoTrack : mAudioTrack;
  uint64_t target = aTarget.ToNanoseconds();

  if (NS_FAILED(Reset())) {
    return NS_ERROR_FAILURE;
  }

  if (mSeekPreroll) {
    uint64_t startTime = 0;
    if (!mBufferedState->GetStartTime(&startTime)) {
      startTime = 0;
    }
    WEBM_DEBUG("Seek Target: %f",
               media::TimeUnit::FromNanoseconds(target).ToSeconds());
    if (target < mSeekPreroll || target - mSeekPreroll < startTime) {
      target = startTime;
    } else {
      target -= mSeekPreroll;
    }
    WEBM_DEBUG("SeekPreroll: %f StartTime: %f Adjusted Target: %f",
               media::TimeUnit::FromNanoseconds(mSeekPreroll).ToSeconds(),
               media::TimeUnit::FromNanoseconds(startTime).ToSeconds(),
               media::TimeUnit::FromNanoseconds(target).ToSeconds());
  }
  int r = nestegg_track_seek(mContext, trackToSeek, target);
  if (r == -1) {
    WEBM_DEBUG("track_seek for track %u to %f failed, r=%d", trackToSeek,
               media::TimeUnit::FromNanoseconds(target).ToSeconds(), r);
    // Try seeking directly based on cluster information in memory.
    int64_t offset = 0;
    bool rv = mBufferedState->GetOffsetForTime(target, &offset);
    if (!rv) {
      WEBM_DEBUG("mBufferedState->GetOffsetForTime failed too");
      return NS_ERROR_FAILURE;
    }

    r = nestegg_offset_seek(mContext, offset);
    if (r == -1) {
      WEBM_DEBUG("and nestegg_offset_seek to %" PRIu64 " failed", offset);
      return NS_ERROR_FAILURE;
    }
    WEBM_DEBUG("got offset from buffered state: %" PRIu64 "", offset);
  }

  mLastAudioFrameTime.reset();
  mLastVideoFrameTime.reset();

  return NS_OK;
}

media::TimeIntervals
WebMDemuxer::GetBuffered()
{
  EnsureUpToDateIndex();
  AutoPinned<MediaResource> resource(mResource.GetResource());

  media::TimeIntervals buffered;

  MediaByteRangeSet ranges;
  nsresult rv = resource->GetCachedRanges(ranges);
  if (NS_FAILED(rv)) {
    return media::TimeIntervals();
  }
  uint64_t duration = 0;
  uint64_t startOffset = 0;
  if (!nestegg_duration(mContext, &duration)) {
    if(mBufferedState->GetStartTime(&startOffset)) {
      duration += startOffset;
    }
    WEBM_DEBUG("Duration: %f StartTime: %f",
               media::TimeUnit::FromNanoseconds(duration).ToSeconds(),
               media::TimeUnit::FromNanoseconds(startOffset).ToSeconds());
  }
  for (uint32_t index = 0; index < ranges.Length(); index++) {
    uint64_t start, end;
    bool rv = mBufferedState->CalculateBufferedForRange(ranges[index].mStart,
                                                        ranges[index].mEnd,
                                                        &start, &end);
    if (rv) {
      NS_ASSERTION(startOffset <= start,
          "startOffset negative or larger than start time");

      if (duration && end > duration) {
        WEBM_DEBUG("limit range to duration, end: %f duration: %f",
                   media::TimeUnit::FromNanoseconds(end).ToSeconds(),
                   media::TimeUnit::FromNanoseconds(duration).ToSeconds());
        end = duration;
      }
      media::TimeUnit startTime = media::TimeUnit::FromNanoseconds(start);
      media::TimeUnit endTime = media::TimeUnit::FromNanoseconds(end);
      WEBM_DEBUG("add range %f-%f", startTime.ToSeconds(), endTime.ToSeconds());
      buffered += media::TimeInterval(startTime, endTime);
    }
  }
  return buffered;
}

bool WebMDemuxer::GetOffsetForTime(uint64_t aTime, int64_t* aOffset)
{
  EnsureUpToDateIndex();
  return mBufferedState && mBufferedState->GetOffsetForTime(aTime, aOffset);
}


//WebMTrackDemuxer
WebMTrackDemuxer::WebMTrackDemuxer(WebMDemuxer* aParent,
                                   TrackInfo::TrackType aType,
                                   uint32_t aTrackNumber)
  : mParent(aParent)
  , mType(aType)
{
  mInfo = mParent->GetTrackInfo(aType, aTrackNumber);
  MOZ_ASSERT(mInfo);
}

WebMTrackDemuxer::~WebMTrackDemuxer()
{
  mSamples.Reset();
}

UniquePtr<TrackInfo>
WebMTrackDemuxer::GetInfo() const
{
  return mInfo->Clone();
}

RefPtr<WebMTrackDemuxer::SeekPromise>
WebMTrackDemuxer::Seek(media::TimeUnit aTime)
{
  // Seeks to aTime. Upon success, SeekPromise will be resolved with the
  // actual time seeked to. Typically the random access point time

  media::TimeUnit seekTime = aTime;
  mSamples.Reset();
  mParent->SeekInternal(aTime);
  mParent->GetNextPacket(mType, &mSamples);

  // Check what time we actually seeked to.
  if (mSamples.GetSize() > 0) {
    const RefPtr<MediaRawData>& sample = mSamples.First();
    seekTime = media::TimeUnit::FromMicroseconds(sample->mTime);
  }
  SetNextKeyFrameTime();

  return SeekPromise::CreateAndResolve(seekTime, __func__);
}

RefPtr<MediaRawData>
WebMTrackDemuxer::NextSample()
{
  while (mSamples.GetSize() < 1 && mParent->GetNextPacket(mType, &mSamples)) {
  }
  if (mSamples.GetSize()) {
    return mSamples.PopFront();
  }
  return nullptr;
}

RefPtr<WebMTrackDemuxer::SamplesPromise>
WebMTrackDemuxer::GetSamples(int32_t aNumSamples)
{
  RefPtr<SamplesHolder> samples = new SamplesHolder;
  if (!aNumSamples) {
    return SamplesPromise::CreateAndReject(DemuxerFailureReason::DEMUXER_ERROR, __func__);
  }

  while (aNumSamples) {
    RefPtr<MediaRawData> sample(NextSample());
    if (!sample) {
      break;
    }
    samples->mSamples.AppendElement(sample);
    aNumSamples--;
  }

  if (samples->mSamples.IsEmpty()) {
    return SamplesPromise::CreateAndReject(DemuxerFailureReason::END_OF_STREAM, __func__);
  } else {
    UpdateSamples(samples->mSamples);
    return SamplesPromise::CreateAndResolve(samples, __func__);
  }
}

void
WebMTrackDemuxer::SetNextKeyFrameTime()
{
  if (mType != TrackInfo::kVideoTrack) {
    return;
  }

  int64_t frameTime = -1;

  mNextKeyframeTime.reset();

  MediaRawDataQueue skipSamplesQueue;
  bool foundKeyframe = false;
  while (!foundKeyframe && mSamples.GetSize()) {
    RefPtr<MediaRawData> sample = mSamples.PopFront();
    if (sample->mKeyframe) {
      frameTime = sample->mTime;
      foundKeyframe = true;
    }
    skipSamplesQueue.Push(sample.forget());
  }
  Maybe<int64_t> startTime;
  if (skipSamplesQueue.GetSize()) {
    const RefPtr<MediaRawData>& sample = skipSamplesQueue.First();
    startTime.emplace(sample->mTimecode);
  }
  // Demux and buffer frames until we find a keyframe.
  RefPtr<MediaRawData> sample;
  while (!foundKeyframe && (sample = NextSample())) {
    if (sample->mKeyframe) {
      frameTime = sample->mTime;
      foundKeyframe = true;
    }
    int64_t sampleTimecode = sample->mTimecode;
    skipSamplesQueue.Push(sample.forget());
    if (!startTime) {
      startTime.emplace(sampleTimecode);
    } else if (!foundKeyframe &&
               sampleTimecode > startTime.ref() + MAX_LOOK_AHEAD) {
      WEBM_DEBUG("Couldn't find keyframe in a reasonable time, aborting");
      break;
    }
  }
  // We may have demuxed more than intended, so ensure that all frames are kept
  // in the right order.
  mSamples.PushFront(Move(skipSamplesQueue));

  if (frameTime != -1) {
    mNextKeyframeTime.emplace(media::TimeUnit::FromMicroseconds(frameTime));
    WEBM_DEBUG("Next Keyframe %f (%u queued %.02fs)",
               mNextKeyframeTime.value().ToSeconds(),
               uint32_t(mSamples.GetSize()),
               media::TimeUnit::FromMicroseconds(mSamples.Last()->mTimecode - mSamples.First()->mTimecode).ToSeconds());
  } else {
    WEBM_DEBUG("Couldn't determine next keyframe time  (%u queued)",
               uint32_t(mSamples.GetSize()));
  }
}

void
WebMTrackDemuxer::Reset()
{
  mSamples.Reset();
  media::TimeIntervals buffered = GetBuffered();
  if (buffered.Length()) {
    WEBM_DEBUG("Seek to start point: %f", buffered.Start(0).ToSeconds());
    mParent->SeekInternal(buffered.Start(0));
    SetNextKeyFrameTime();
  } else {
    mNextKeyframeTime.reset();
  }
}

void
WebMTrackDemuxer::UpdateSamples(nsTArray<RefPtr<MediaRawData>>& aSamples)
{
  if (mNextKeyframeTime.isNothing() ||
      aSamples.LastElement()->mTime >= mNextKeyframeTime.value().ToMicroseconds()) {
    SetNextKeyFrameTime();
  }
}

nsresult
WebMTrackDemuxer::GetNextRandomAccessPoint(media::TimeUnit* aTime)
{
  if (mNextKeyframeTime.isNothing()) {
    // There's no next key frame.
    *aTime =
      media::TimeUnit::FromMicroseconds(std::numeric_limits<int64_t>::max());
  } else {
    *aTime = mNextKeyframeTime.ref();
  }
  return NS_OK;
}

RefPtr<WebMTrackDemuxer::SkipAccessPointPromise>
WebMTrackDemuxer::SkipToNextRandomAccessPoint(media::TimeUnit aTimeThreshold)
{
  uint32_t parsed = 0;
  bool found = false;
  RefPtr<MediaRawData> sample;

  WEBM_DEBUG("TimeThreshold: %f", aTimeThreshold.ToSeconds());
  while (!found && (sample = NextSample())) {
    parsed++;
    if (sample->mKeyframe && sample->mTime >= aTimeThreshold.ToMicroseconds()) {
      found = true;
      mSamples.Reset();
      mSamples.PushFront(sample.forget());
    }
  }
  SetNextKeyFrameTime();
  if (found) {
    WEBM_DEBUG("next sample: %f (parsed: %d)",
               media::TimeUnit::FromMicroseconds(sample->mTime).ToSeconds(),
               parsed);
    return SkipAccessPointPromise::CreateAndResolve(parsed, __func__);
  } else {
    SkipFailureHolder failure(DemuxerFailureReason::END_OF_STREAM, parsed);
    return SkipAccessPointPromise::CreateAndReject(Move(failure), __func__);
  }
}

media::TimeIntervals
WebMTrackDemuxer::GetBuffered()
{
  return mParent->GetBuffered();
}

void
WebMTrackDemuxer::BreakCycles()
{
  mParent = nullptr;
}

#undef WEBM_DEBUG
} // namespace mozilla