/// <summary>
/// Reads the <see cref="VolumeDescriptor"/> at the current position of the image file.
/// </summary>
/// <returns>The <see cref="VolumeDescriptor"/> located at the current file position.</returns>
VolumeDescriptor ReadVolumeDescriptor()
{
var buffer = Reader.ReadBytes(DefaultSectorSize);
var type = (VolumeDescriptorType)buffer[0];
if (type == VolumeDescriptorType.Primary)
{
var descriptor = new BasicVolumeDescriptor();
descriptor.VolumeDescriptorType = type;
descriptor.StandardIdentifier = Encodings.ASCII.GetString(buffer, 1, 5);
descriptor.VolumeDescriptorVersion = buffer[6];
descriptor.SystemIdentifier = Encodings.ASCII.GetString(buffer, 8, 32).Trim(' ');
descriptor.VolumeIdentifier = Encodings.ASCII.GetString(buffer, 40, 32).Trim(' ');
descriptor.VolumeSpaceSize = BinaryIO.ReadUInt32FromBuffer(buffer, 80, Endian.LittleEndian);
descriptor.VolumeSetSize = BinaryIO.ReadUInt16FromBuffer(buffer, 120, Endian.LittleEndian);
descriptor.VolumeSequenceNumber = BinaryIO.ReadUInt16FromBuffer(buffer, 124, Endian.LittleEndian);
descriptor.LogicalBlockSize = BinaryIO.ReadUInt16FromBuffer(buffer, 128, Endian.LittleEndian);
descriptor.PathTableSize = BinaryIO.ReadUInt32FromBuffer(buffer, 132, Endian.LittleEndian);
descriptor.TypeLPathTableLocation = BinaryIO.ReadUInt32FromBuffer(buffer, 140, Endian.LittleEndian);
descriptor.OptionalTypeLPathTableLocation = BinaryIO.ReadUInt32FromBuffer(buffer, 144, Endian.LittleEndian);
descriptor.TypeMPathTableLocation = BinaryIO.ReadUInt32FromBuffer(buffer, 148, Endian.BigEndian);
descriptor.OptionalTypeMPathTableLocation = BinaryIO.ReadUInt32FromBuffer(buffer, 152, Endian.BigEndian);
descriptor.RootDirectory = ReadDirectoryRecord(buffer, 156);
descriptor.VolumeSetIdentifier = Encodings.ASCII.GetString(buffer, 190, 128).Trim(' ');
descriptor.PublisherIdentifier = Encodings.ASCII.GetString(buffer, 318, 128).Trim(' ');
descriptor.DataPreparerIdentifier = Encodings.ASCII.GetString(buffer, 446, 128).Trim(' ');
descriptor.ApplicationIdentifier = Encodings.ASCII.GetString(buffer, 574, 128).Trim(' ');
descriptor.CopyrightFileIdentifier = Encodings.ASCII.GetString(buffer, 702, 37).Trim(' ');
descriptor.AbstractFileIdentifier = Encodings.ASCII.GetString(buffer, 739, 37).Trim(' ');
descriptor.BibliographicFileIdentifier = Encodings.ASCII.GetString(buffer, 776, 37).Trim(' ');
descriptor.CreationDateAndTime = ReadVolumeDescriptorDateTime(buffer, 813);
descriptor.ModificationDateAndTime = ReadVolumeDescriptorDateTime(buffer, 830);
descriptor.ExpirationDateAndTime = ReadVolumeDescriptorDateTime(buffer, 847);
descriptor.EffectiveDateAndTime = ReadVolumeDescriptorDateTime(buffer, 864);
descriptor.FileStructureVersion = buffer[881];
return(descriptor);
}
if (type == VolumeDescriptorType.SetTerminator)
{
var descriptor = new SetTerminatorVolumeDescriptor();
descriptor.VolumeDescriptorType = type;
descriptor.StandardIdentifier = Encodings.ASCII.GetString(buffer, 1, 5);
descriptor.VolumeDescriptorVersion = buffer[6];
return(descriptor);
}
throw new Exception();
}
void WriteSetTerminatorVolumeDescriptor(BinaryWriter writer, SetTerminatorVolumeDescriptor descriptor)
{
Assert.IsNotNull(writer, nameof(writer));
Assert.IsNotNull(descriptor, nameof(descriptor));
var buffer = new Byte[DefaultSectorSize];
buffer[0] = (Byte)descriptor.VolumeDescriptorType;
BinaryIO.WriteIntoBuffer(buffer, 1, Encodings.ASCII, descriptor.StandardIdentifier, 5, ' ');
buffer[6] = descriptor.VolumeDescriptorVersion;
writer.Write(buffer);
}
