public ServerMedia(IMediaDirectory directory, Guid guid, UInt64 idPersistentMedia, IArchiveDirectory archiveDirectory) : base(directory, guid, idPersistentMedia)
{
IdPersistentMedia = idPersistentMedia;
_archiveDirectory = archiveDirectory;
_isArchived = new Lazy <bool>(() => _archiveDirectory == null ? false :_archiveDirectory.DbArchiveContainsMedia(this));
}