public void Encode(Stream input, Stream output, IEnumerable <Match> matches)
{
var matchArray = matches.ToArray();
var compressedLength = CalculateCompressedLength(input.Length, matchArray, out var lastRawLength);
var block = new Block();
using (var inputReverseStream = new ReverseStream(input, input.Length))
using (var outputReverseStream = new ReverseStream(output, compressedLength + lastRawLength))
{
foreach (var match in matchArray)
{
while (match.Position < input.Length - inputReverseStream.Position)
{
if (block.codeBlockPosition == 0)
{
WriteAndResetBuffer(outputReverseStream, block);
}
block.codeBlockPosition--;
block.buffer[block.bufferLength++] = (byte)inputReverseStream.ReadByte();
}
var byte1 = ((byte)(match.Length - 3) << 4) | (byte)((match.Displacement - 3) >> 8);
var byte2 = match.Displacement - 3;
if (block.codeBlockPosition == 0)
{
WriteAndResetBuffer(outputReverseStream, block);
}
block.codeBlock |= (byte)(1 << --block.codeBlockPosition);
block.buffer[block.bufferLength++] = (byte)byte1;
block.buffer[block.bufferLength++] = (byte)byte2;
inputReverseStream.Position += match.Length;
}
// Flush remaining buffer to stream
WriteAndResetBuffer(outputReverseStream, block);
// Write any data after last match as raw unbuffered data
while (inputReverseStream.Position < inputReverseStream.Length)
{
outputReverseStream.WriteByte((byte)inputReverseStream.ReadByte());
}
output.Position = compressedLength + lastRawLength;
WriteFooterInformation(input, output, lastRawLength);
}
}
public void Decode(Stream input, Stream output)
{
using var br = new BinaryReaderX(input, true);
var header = br.ReadType <CrilaylaHeader>();
if (header.magic != "CRILAYLA" || header.magic == "\0\0\0\0\0\0\0\0")
{
throw new InvalidCompressionException("Crilayla");
}
// Copy raw part
input.Position = input.Length - RawSize_;
output.Write(br.ReadBytes(RawSize_), 0, RawSize_);
// Decompress
var compStream = new SubStream(input, 0x10, input.Length - RawSize_ - 0x10);
var reverseCompStream = new ReverseStream(compStream, compStream.Length);
var reverseOutputStream = new ReverseStream(output, header.decompSize + RawSize_);
var circularBuffer = new CircularBuffer(0x2002);
using var reverseBr = new BinaryReaderX(reverseCompStream, ByteOrder.LittleEndian, BitOrder.MostSignificantBitFirst, 1);
while (reverseOutputStream.Position < reverseOutputStream.Length - RawSize_)
{
if (!reverseBr.ReadBit())
{
var value = reverseBr.ReadBits <byte>(8);
reverseOutputStream.WriteByte(value);
circularBuffer.WriteByte(value);
continue;
}
var displacement = reverseBr.ReadBits <short>(13) + 3;
var length = ReadLength(reverseBr) + 3;
circularBuffer.Copy(reverseOutputStream, displacement, length);
}
}