Alexandria.Platforms.NintendoDS.Extensions.DecompressLZ77 C# (CSharp) Метод

        public static byte[] DecompressLZ77(this BinaryReader reader, long inputEnd, int outputSize, bool acceptInputOverflow = false, bool ffEscape = false)
        {
            byte[] output = new byte[outputSize];
            int outputOffset = 0;
            Stream stream = reader.BaseStream;

            while (outputOffset < outputSize) {
                if (stream.Position >= inputEnd) {
                    if (acceptInputOverflow) {
                        byte[] slice = new byte[outputOffset];
                        Array.Copy(output, slice, outputOffset);
                        return slice;
                    }

                    throw new OverflowException(String.Format("Input overflow at inputOffset {0}, for outputOffset {1} of outputSize {2}.", stream.Position, outputOffset, outputSize));
                }

                var flags = reader.ReadByte();
                if (ffEscape && flags == 0xFF) {
                    while (stream.Position < inputEnd && outputOffset < outputSize && (flags = reader.ReadByte()) != 0xFF)
                        output[outputOffset++] = flags;
                } else {
                    for (int flagBit = 7; flagBit >= 0 && outputOffset < outputSize && stream.Position < inputEnd; flagBit--) {
                        if ((flags & (1 << flagBit)) != 0) {
                            if (stream.Position + 2 > inputEnd) {
                                reader.ReadByte();
                                break;
                            }

                            var code = reader.ReadUInt16();
                            var displacement = (((code & 15) << 8) | (code >> 8)) + 1;
                            var length = ((code >> 4) & 15) + 3;

                            for (int index = 0; index < length && outputOffset < outputSize; index++, outputOffset++)
                                output[outputOffset] = (outputOffset - displacement >= 0) ? output[outputOffset - displacement] : (byte)0;
                        } else
                            output[outputOffset++] = reader.ReadByte();
                    }
                }
            }

            return output;
        }