bool TagReader::SaveSongRatingToFile(
    const QString& filename, const pb::tagreader::SongMetadata& song) const {
  if (filename.isNull()) return false;

  qLog(Debug) << "Saving song rating tags to" << filename;
  if (song.rating() < 0) {
    // The FMPS spec says unrated == "tag not present". For us, no rating
    // results in rating being -1, so don't write anything in that case.
    // Actually, we should also remove tag set in this case, but in
    // Clementine it is not possible to unset rating i.e. make a song "unrated".
    qLog(Debug) << "Unrated: do nothing";
    return true;
  }

  std::unique_ptr<TagLib::FileRef> fileref(factory_->GetFileRef(filename));

  if (!fileref || fileref->isNull())  // The file probably doesn't exist
    return false;

  if (TagLib::MPEG::File* file =
          dynamic_cast<TagLib::MPEG::File*>(fileref->file())) {
    TagLib::ID3v2::Tag* tag = file->ID3v2Tag(true);

    // Save as FMPS
    SetUserTextFrame("FMPS_Rating", QString::number(song.rating()), tag);

    // Also save as POPM
    TagLib::ID3v2::PopularimeterFrame* frame = GetPOPMFrameFromTag(tag);
    frame->setRating(ConvertToPOPMRating(song.rating()));

  } else if (TagLib::FLAC::File* file =
                 dynamic_cast<TagLib::FLAC::File*>(fileref->file())) {
    TagLib::Ogg::XiphComment* vorbis_comments = file->xiphComment(true);
    SetFMPSRatingVorbisComments(vorbis_comments, song);
  } else if (TagLib::Ogg::XiphComment* tag =
                 dynamic_cast<TagLib::Ogg::XiphComment*>(
                     fileref->file()->tag())) {
    SetFMPSRatingVorbisComments(tag, song);
  }
#ifdef TAGLIB_WITH_ASF
  else if (TagLib::ASF::File* file =
               dynamic_cast<TagLib::ASF::File*>(fileref->file())) {
    TagLib::ASF::Tag* tag = file->tag();
    tag->addAttribute("FMPS/Rating", NumberToASFAttribute(song.rating()));
  }
#endif
  else if (TagLib::MP4::File* file =
               dynamic_cast<TagLib::MP4::File*>(fileref->file())) {
    TagLib::MP4::Tag* tag = file->tag();
    tag->itemListMap()[kMP4_FMPS_Rating_ID] = TagLib::StringList(
        QStringToTaglibString(QString::number(song.rating())));
  } else {
    // Nothing to save: stop now
    return true;
  }

  bool ret = fileref->save();
#ifdef Q_OS_LINUX
  if (ret) {
    // Linux: inotify doesn't seem to notice the change to the file unless we
    // change the timestamps as well. (this is what touch does)
    utimensat(0, QFile::encodeName(filename).constData(), nullptr, 0);
  }
#endif  // Q_OS_LINUX
  return ret;
}
bool TagReader::SaveSongStatisticsToFile(
    const QString& filename, const pb::tagreader::SongMetadata& song) const {
  if (filename.isNull()) return false;

  qLog(Debug) << "Saving song statistics tags to" << filename;

  std::unique_ptr<TagLib::FileRef> fileref(factory_->GetFileRef(filename));

  if (!fileref || fileref->isNull())  // The file probably doesn't exist
    return false;

  if (TagLib::MPEG::File* file =
          dynamic_cast<TagLib::MPEG::File*>(fileref->file())) {
    TagLib::ID3v2::Tag* tag = file->ID3v2Tag(true);

    // Save as FMPS
    SetUserTextFrame("FMPS_PlayCount", QString::number(song.playcount()), tag);
    SetUserTextFrame("FMPS_Rating_Amarok_Score",
                     QString::number(song.score() / 100.0), tag);

    // Also save as POPM
    TagLib::ID3v2::PopularimeterFrame* frame = GetPOPMFrameFromTag(tag);
    frame->setCounter(song.playcount());

  } else if (TagLib::FLAC::File* file =
                 dynamic_cast<TagLib::FLAC::File*>(fileref->file())) {
    TagLib::Ogg::XiphComment* vorbis_comments = file->xiphComment(true);
    SetFMPSStatisticsVorbisComments(vorbis_comments, song);
  } else if (TagLib::Ogg::XiphComment* tag =
                 dynamic_cast<TagLib::Ogg::XiphComment*>(
                     fileref->file()->tag())) {
    SetFMPSStatisticsVorbisComments(tag, song);
  }
#ifdef TAGLIB_WITH_ASF
  else if (TagLib::ASF::File* file =
               dynamic_cast<TagLib::ASF::File*>(fileref->file())) {
    TagLib::ASF::Tag* tag = file->tag();
    tag->addAttribute("FMPS/Playcount", NumberToASFAttribute(song.playcount()));
    tag->addAttribute("FMPS/Rating_Amarok_Score",
                      NumberToASFAttribute(song.score() / 100.0));
  }
#endif
  else if (TagLib::MP4::File* file =
               dynamic_cast<TagLib::MP4::File*>(fileref->file())) {
    TagLib::MP4::Tag* tag = file->tag();
    tag->itemListMap()[kMP4_FMPS_Score_ID] = TagLib::StringList(
        QStringToTaglibString(QString::number(song.score() / 100.0)));
    tag->itemListMap()[kMP4_FMPS_Playcount_ID] =
        TagLib::StringList(TagLib::String::number(song.playcount()));
  } else {
    // Nothing to save: stop now
    return true;
  }

  bool ret = fileref->save();
#ifdef Q_OS_LINUX
  if (ret) {
    // Linux: inotify doesn't seem to notice the change to the file unless we
    // change the timestamps as well. (this is what touch does)
    utimensat(0, QFile::encodeName(filename).constData(), nullptr, 0);
  }
#endif  // Q_OS_LINUX
  return ret;
}