LZSS

public class LZSS
    {
        public static byte[] Decompress(byte[] data)
        {
            bool debug = false;
            byte[] decompBuffer = new byte[0x0FFFFFFF];
            int decompPointer = 4096;

            //List<byte> decompBuffer = new List<byte>();
            //decompBuffer.AddRange(new byte[4096]);

            int c = 0;
            int len = BitConverter.ToInt32(data, c);
            Console.WriteLine("Compressed Binary Length: " + len.ToString("X8"));
            c += 4;
            //c += 4;

            while ( c < len)
            {
                byte flag = data[c];

                if (debug)
                {
                    Console.Write((c - 4096).ToString("X8"));
                    Console.Write(": ");
                    Console.Write(data[c].ToString("X2") + " (flag byte 0b");
                    for (int i = 7; i >= 0; i--)
                    {
                        Console.Write((((flag & (1 << i))) != 0) ? 1 : 0);
                    }
                    Console.WriteLine(")");
                }
                c++;

                for (int i = 0; i < 8; i++)
                {
                    if ((flag & (1 << i)) == 0)
                    {
                        int offset = (data[c + 0] + ((data[c + 1] & 0xF0) << 4));
                        offset = (offset >> 11) == 0 ? offset : -1 ^ 0xFFF | offset;
                        int length = ((data[c + 1] & 0x0F)) + 3;

                        offset += 18;

                        if (debug)
                        {

                            Console.Write("             ");
                            Console.Write(data[c].ToString("X2") + " " + data[c + 1].ToString("X2") + "\t" + length + " bytes from 0x" + offset.ToString("X3"));
                        }
                        //offset = 4096 - offset;

                        int start;

                        start = ((int)((decompPointer - 0) & 0xFFFFF000) + offset);

                        if (debug)
                        {
                            Console.Write("\t 0x");
                            Console.Write(decompPointer.ToString("X8") + ": ");
                        }

                        for (int j = start; j < start + length; j++)
                        {
                            decompBuffer[decompPointer] = decompBuffer[j];
                            decompPointer++;
                            if (debug)
                            {
                                Console.Write(decompBuffer[j].ToString("X2"));
                                Console.Write(" ");
                            }
                        }
                        if (debug)
                        {
                            Console.WriteLine("   (i.e. copied from 0x" + start.ToString("X8") + ")");
                        }
                        //decompBuffer.AddRange(decompBuffer.Skip((decompBuffer.Count()) - (4096 - offset)).Take(length).ToArray());
                        c += 2;
                    }
                    else
                    {
                        if (debug)
                        {
                            Console.Write("             ");
                            Console.Write(data[c].ToString("X2") + "   \tliteral byte");
                            Console.Write("     \t 0x");
                            Console.Write(decompPointer.ToString("X8") + ": ");
                            Console.Write(data[c].ToString("X2"));
                            Console.WriteLine(" ");
                        }

                        decompBuffer[decompPointer] = data[c];
                        decompPointer++;
                        c++;
                    }
                }
                if (debug)
                {
                    Console.WriteLine((c).ToString("X8") + "/" + len.ToString("X8"));
                }
            }
            return decompBuffer.Take(decompPointer).Skip(4096).ToArray();
        }
    }