private static void WriteChunk(RiffChunk chunk, BinaryWriter writer)
{
var listChunk = chunk as ListChunk;
if (listChunk == null)
{
throw new FormatException("\"chunk\" must be a ListChunk");
}
writer.Write(listChunk.TypeId.ToUInt32());
listChunk._writeProcedure?.Invoke(listChunk, writer);
}
private static void ValidateChunk(RiffChunk chunk, ref ValidationResult result)
{
var listChunk = chunk as ListChunk;
if (listChunk == null)
{
throw new FormatException("\"chunk\" must be a ListChunk");
}
if (listChunk.TypeId == FourCc.Zero)
{
result.EditValidity(Validity.Invalid, "\"TypeId\" cannot be equal to zero");
}
listChunk._validationProcedure?.Invoke(listChunk, ref result);
}
private static void ReadChunk(RiffChunk chunk, BinaryReader reader)
{
var listChunk = chunk as ListChunk;
if (listChunk == null)
{
throw new FormatException("\"chunk\" must be a ListChunk");
}
// Verify that the type ID read from the stream matches the expected type ID
var typeIdRead = reader.ReadFourCc();
var typeIdExpected = listChunk.TypeId;
if (typeIdRead != typeIdExpected)
{
listChunk.TypeId = typeIdRead;
throw new RiffException(
$"The LIST chunk TypeId read from the stream ({typeIdRead}) does not match the expected value ({typeIdExpected})");
}
// Run the read procedure
listChunk._readProcedure?.Invoke(listChunk, reader);
// Only predefined chunk IDs will be read into the LIST chunk
// If the procedure list is empty, the entire contents of the LIST chunk will be ignored
if (listChunk._subchunkProcedures.Count == 0)
{
throw new RiffException("No subchunk IDs have been defined");
}
// Add all defined subchunks
var bytesRemaining = listChunk.StreamIndicatedSize - 4;
while (bytesRemaining > 0 && (reader.BaseStream.Length - reader.BaseStream.Position > 2))
{
var chunkId = reader.ReadFourCc();
if (listChunk._subchunkProcedures.Exists(set => set is ListChunkProcedureSet && set.Id == chunkId))
{
var chunkTypeId = reader.PeekFourCc(4);
var listChunkProcedure = listChunk._subchunkProcedures.OfType <ListChunkProcedureSet>()
.First(set => set.Id == chunkId && set.TypeId == chunkTypeId);
if (listChunkProcedure != null)
{
listChunk.Children.Add(new ListChunk(reader, listChunkProcedure));
}
}
else if (listChunk._subchunkProcedures.Exists(set => set.Id == chunkId))
{
var chunkProcedure = listChunk._subchunkProcedures.First(set => set.Id == chunkId);
if (chunkProcedure != null)
{
listChunk.Children.Add(new RiffChunk(reader, chunkProcedure));
}
bytesRemaining -= listChunk.Children.Last.ActualSize;
}
else
{
bytesRemaining -= SkipUnknownChunk(reader) + listChunk.HeaderSize;
}
}
}