public static VmgInfo Create(Stream stream)
{
Span <byte> buffer = stackalloc byte[32];
var id = buffer.Slice(0, 12);
stream.Read(id);
if (!id.SequenceEqual(Magic))
{
ThrowHelper.ThrowInvalidDataException("File doesn't start with VMG IFO magic.");
}
using var reader = new BigEndianBinaryReader(stream, Encoding.UTF8, true);
stream.Seek(Constants.VersionNumberOffset, SeekOrigin.Begin);
var versionSpan = buffer.Slice(0, 2);
stream.Read(versionSpan); // 0x20
var info = new VmgInfo();
if (!IfoHelper.TryParseVersion(versionSpan, out var version))
{
ThrowHelper.ThrowInvalidDataException("First byte of the version number should be 0.");
}
info.Version = version;
info.Category = reader.ReadUInt32(); // 0x22
info.NumberOfVolumes = reader.ReadUInt16(); // 0x26
info.VolumeNumber = reader.ReadUInt16(); // 0x28
info.SideId = reader.ReadByte(); // 0x2a
stream.Seek(Constants.NumberOfTitleSetsOffset, SeekOrigin.Begin);
info.NumberOfTitleSets = reader.ReadUInt16(); // 0x3e
int bytesRead = stream.Read(buffer); // 0x40
Debug.Assert(
bytesRead == Constants.ProviderIdLength,
$"Expected {nameof(bytesRead)} to be {Constants.ProviderIdLength}, got {bytesRead}");
info.ProviderId = Encoding.ASCII.GetString(buffer);
info.VmgPos = reader.ReadUInt64(); // 0x60
stream.Seek(Constants.TableOfTitlesPointerOffset, SeekOrigin.Begin);
stream.Seek(reader.ReadUInt32() * Constants.DvdSectorSize, SeekOrigin.Begin);
info.TableOfTitles = ReadTableOfTitles(reader);
stream.Seek(Constants.VideoAttributesOffset, SeekOrigin.Begin);
info.VideoAttributes = new VideoAttributes(reader.ReadUInt16()); // 0x100
info.AudioStreams = reader.ReadUInt16(); // 0x102
info.AudioAttributes = new AudioAttributes(reader.ReadUInt64()); // 0x104
return(info);
}
public static VmgInfo GetVmgInfo(string rootDir)
{
var videoTsDir = rootDir;
foreach (var dir in Directory.EnumerateDirectories(rootDir))
{
if (dir.Equals("VIDEO_TS", StringComparison.OrdinalIgnoreCase))
{
videoTsDir = dir;
}
}
var files = Directory.GetFiles(videoTsDir);
var vmgFile = Array.Find(files, x => x.Equals("VIDEO_TS.IFO", StringComparison.OrdinalIgnoreCase))
?? Array.Find(files, x => x.Equals("VIDEO_TS.BUP", StringComparison.OrdinalIgnoreCase));
if (vmgFile == null)
{
ThrowHelper.ThrowFileNotFoundException("Couldn't find a 'VIDEO_TS.IFO' or 'VIDEO_TS.BUP' file.");
}
return(VmgInfo.Create(vmgFile));
}
