using System.IO;
using Org.BouncyCastle.Utilities.IO;

namespace Org.BouncyCastle.Crypto.Digests;

public class NullDigest : IDigest
{
	private readonly MemoryStream bOut = new MemoryStream();

	public string AlgorithmName => "NULL";

	public int GetByteLength()
	{
		return 0;
	}

	public int GetDigestSize()
	{
		return (int)bOut.Length;
	}

	public void Update(byte b)
	{
		bOut.WriteByte(b);
	}

	public void BlockUpdate(byte[] inBytes, int inOff, int len)
	{
		bOut.Write(inBytes, inOff, len);
	}

	public int DoFinal(byte[] outBytes, int outOff)
	{
		try
		{
			return Streams.WriteBufTo(bOut, outBytes, outOff);
		}
		finally
		{
			Reset();
		}
	}

	public void Reset()
	{
		bOut.SetLength(0L);
	}
}