public static async Task SkipAsync(IBinaryStream stream)
{
stream.Position += 3;
var majorVersion = await stream.ReadByteAsync().ConfigureAwait(false);
var revision = await stream.ReadByteAsync().ConfigureAwait(false);
var flags = await stream.ReadByteAsync().ConfigureAwait(false);
var size = Id3v2.DecodeSize(await stream.ReadUInt32Async(ByteOrder.BigEndian).ConfigureAwait(false));
var newStreamPosition = stream.Position + size;
if (await stream.GetLengthAsync().ConfigureAwait(false) < newStreamPosition)
{
newStreamPosition = await stream.GetLengthAsync().ConfigureAwait(false);
}
stream.Position = newStreamPosition;
}
public static async Task <Id3v2> ParseAsync(IBinaryStream stream)
{
stream.Position += 3;
var id3v2 = new Id3v2();
var majorVersion = await stream.ReadByteAsync().ConfigureAwait(false);
var revision = await stream.ReadByteAsync().ConfigureAwait(false);
var flags = await stream.ReadByteAsync().ConfigureAwait(false);
var size = Id3v2.DecodeSize(await stream.ReadUInt32Async(ByteOrder.BigEndian).ConfigureAwait(false));
var endingPosition = stream.Position + size;
while (stream.Position < endingPosition)
{
var frameId = await stream.ReadStringAsync(4).ConfigureAwait(false);
if (!Id3v2.IsValidAlphaNumeric(frameId))
{
stream.Position = endingPosition;
break;
}
var frameSize = 0U;
switch (majorVersion)
{
case 4:
frameSize = Id3v2.DecodeSize(await stream.ReadUInt32Async(ByteOrder.BigEndian).ConfigureAwait(false));
break;
case 3:
frameSize = await stream.ReadUInt32Async(ByteOrder.BigEndian).ConfigureAwait(false);
break;
default:
throw new NotSupportedException();
}
var frameFlags = await stream.ReadUInt16Async(ByteOrder.LittleEndian).ConfigureAwait(false);
switch (frameId)
{
case "TIT2":
id3v2.Title = Id3v2.DecodeString(await stream.ReadAsync(frameSize).ConfigureAwait(false));
break;
case "TALB":
id3v2.Album = Id3v2.DecodeString(await stream.ReadAsync(frameSize).ConfigureAwait(false));
break;
case "TOAL":
break;
case "TPE1":
id3v2.Artist = Id3v2.DecodeString(await stream.ReadAsync(frameSize).ConfigureAwait(false));
break;
case "TPE2":
id3v2.AlbumArtist = Id3v2.DecodeString(await stream.ReadAsync(frameSize).ConfigureAwait(false));
break;
case "TRCK":
var track = Id3v2.DecodeString(await stream.ReadAsync(frameSize).ConfigureAwait(false));
if (track != null)
{
id3v2.Track = ParseTrack(track);
}
break;
case "TYER":
var year = Id3v2.DecodeString(await stream.ReadAsync(frameSize).ConfigureAwait(false));
if (year != null)
{
id3v2.Year = ParseYear(year);
}
break;
case "APIC":
var readBytes = 0U;
var encoding = (FrameEncoding)await stream.ReadByteAsync().ConfigureAwait(false);
readBytes++;
while (await stream.ReadByteAsync().ConfigureAwait(false) != 0) // MIME type <text string> $00
{
readBytes++;
}
readBytes++;
var pictureType = await stream.ReadByteAsync().ConfigureAwait(false);
readBytes++;
while (await stream.ReadByteAsync().ConfigureAwait(false) != 0) // <text string according to encoding> $00 (00)
{
readBytes++;
}
id3v2.Cover = new DataLocation(stream.Position, frameSize - readBytes - 1);
stream.Position += frameSize - readBytes - 1;
break;
case "TCON":
case "COMM":
default:
stream.Position += frameSize;
break;
}
}
return(id3v2);
}