/// <summary>
/// ID3V2フレームヘッダを解析
/// </summary>
/// <param name="buffer"></param>
/// <param name="version"></param>
/// <returns></returns>
private static Frame readFrameHeader(byte[] buffer, ID3V2_VER version)
{
if (buffer[0] == 0)
{
throw new EndOfTagException();
}
FrameID fid;
int size;
FRAME_FLAG flag = 0;
switch (version)
{
case ID3V2_VER.ID3V22:
fid = FRAMES.FirstOrDefault(_ => _.Name2 == Encoding.ASCII.GetString(buffer, 0, 3));
size = (int)ReadUInt24(buffer, 3);
break;
case ID3V2_VER.ID3V23:
fid = FRAMES.FirstOrDefault(_ => _.Name3 == Encoding.ASCII.GetString(buffer, 0, 4));
size = (int)ReadUInt32(buffer, 4);
flag = (FRAME_FLAG)(((uint)buffer[8] << 7) + (((uint)buffer[9] >> 4) & 0x0F) + (((uint)buffer[9] << 1) & 0x40));
break;
case ID3V2_VER.ID3V24:
fid = FRAMES.FirstOrDefault(_ => _.Name4 == Encoding.ASCII.GetString(buffer, 0, 4));
size = (int)ReadUInt28(buffer, 4);
flag = (FRAME_FLAG)(((uint)buffer[8] << 8) + buffer[9]);
break;
default:
throw new ArgumentOutOfRangeException();
}
return(new Frame()
{
ID = fid, Size = size, Flag = flag
});
}
//public readonly ID3V2Ver Ver;
public FrameID(string name2, string name3, string name4, string asApe, string desc, FRAME_TYPE type, ID3V2_VER ver)
{
this.Name2 = name2;
this.Name3 = name3;
this.Name4 = name4;
this.AsApe = asApe;
this.Desc = desc;
this.Type = type;
//this.Ver = ver;
}
