public (IInstruction Instruction, int AdditionalBytes) Read(byte[] data, int start = 0, int?length = null)
{
length = RangeUtils.Calculate(data.Length, start, length);
if (length < 0)
{
throw new ArgumentException("Length cannot be negative.");
}
else if (length < Word.ByteCount)
{
return(null, Word.ByteCount - length.Value);
}
else if (length > InstructionSet.MaxInstructionSize)
{
throw new ArgumentException($"Length cannot be greater than the max size of {InstructionSet.MaxInstructionSize}.");
}
else if (length.Value % Word.ByteCount != 0)
{
throw new ArgumentException($"Length must be in words (2 bytes).");
}
else
{
IEnumerable <Word> GetWords()
{
for (int i = 0; i < length.Value; i += Word.ByteCount)
{
yield return((ushort)new BitArray(new byte[] { data[start + i + 1], data[start + i] }).GetValue());
}
}
(IInstruction instruction, int additionalWords) = ReadWords(GetWords());
if (instruction != null)
{
return(instruction, 0);
}
else
{
return(null, additionalWords *Word.ByteCount);
}
}
}
public (IInstruction Instruction, int AdditionalBytes) Read(byte[] data, int start = 0, int?length = null)
{
length = RangeUtils.Calculate(data.Length, start, length);
if (length < 0)
{
throw new ArgumentException();
}
else if (length < 2)
{
return(null, 2 - length.Value);
}
else
{
InstructionId id = GetInstructionId(data, start);
if (instructions.TryGetValue(id, out InstructionReader reader))
{
return(reader.Read(data, start, length));
}
throw new InvalidOperationException($"No reader registered for {id}.");
}
}
