public static byte[] decode(byte[] src)
{
if (!IsYaz0(src))
{
return(src);
}
uint decompressedSize = EndianBytesOperator.readUInt(src, 0x04);
byte[] dst = new byte[decompressedSize];
uint srcPos = 0x10;
uint dstPos = 0;
byte Opcode = 0x00;
List <KeyValuePair <int, KeyValuePair <int, int> > > finds = new List <KeyValuePair <int, KeyValuePair <int, int> > >();
while (true)
{
Opcode = src[srcPos];
srcPos++;
for (int i = 0; i < 8; i++, Opcode <<= 1)
{
if ((Opcode & 0x80) != 0)
{
dst[dstPos] = src[srcPos];
dstPos++;
srcPos++;
}
else
{
byte b1 = src[srcPos];
byte b2 = src[srcPos + 1];
srcPos += 2;
uint copyLen = 0;
if ((b1 >> 4) == 0)
{
copyLen = (uint)src[srcPos] + 0x12;
srcPos++;
}
else
{
copyLen = (uint)(b1 >> 4) + 0x02;
}
uint dist = (uint)((b1 & 0x0F) << 8 | b2) + 1;
uint copyPos = dstPos - dist;
finds.Add(new KeyValuePair <int, KeyValuePair <int, int> >((int)dstPos, new KeyValuePair <int, int>((int)copyPos, (int)copyLen)));
for (int j = 0; j < copyLen; j++)
{
dst[dstPos] = dst[copyPos];
dstPos++;
copyPos++;
}
}
if (dstPos >= decompressedSize)
{
return(dst);
}
}
}
}
public static bool IsYaz0(byte[] bytes)
{
return(EndianBytesOperator.readString(bytes, 0, 4) == "Yaz0");
}
public static byte[] encode(byte[] src)
{
//find need compressed position
uint curPos = 0;
uint endPos = (uint)src.Length;
List <KeyValuePair <uint, KeyValuePair <uint, uint> > > finds = new List <KeyValuePair <uint, KeyValuePair <uint, uint> > >();
while (curPos + 0x03 <= endPos)
{
var find = searchNextNCPoses(src, curPos, endPos);
if (find[0].Value.Value != 0)
{
finds.AddRange(find);
}
curPos = find[find.Count - 1].Key + find[find.Count - 1].Value.Value;
}
//compress
byte[] temp = new byte[src.Length + src.Length / 8];
uint writeLen = 0;
uint srcPos = 0;
uint dstPos = 0x01;
uint opcodePos = 0;
uint cycle = 0x00;
foreach (var find in finds)
{
//write data that does not need to be compressed
while (srcPos < find.Key)
{
if (cycle == 8)
{
opcodePos = dstPos;
dstPos++;
cycle = 0x00;
}
temp[opcodePos] = (byte)(temp[opcodePos] | 0x80 >> (int)cycle);
cycle++;
temp[dstPos] = src[srcPos];
dstPos++;
srcPos++;
}
//write data that need to compressed
if (cycle == 8)
{
opcodePos = dstPos;
dstPos++;
cycle = 0x00;
}
cycle++;
uint findLen = find.Value.Value;
uint findPos = find.Value.Key;
uint pos = find.Key;
uint dist = pos - findPos - 1;
if (findLen < 0x12)
{
byte b1 = (byte)((findLen - 2) << 4 | dist >> 8);
byte b2 = (byte)(dist & 0xFF);
temp[dstPos] = b1;
temp[dstPos + 1] = b2;
dstPos += 2;
}
else
{
byte b1 = (byte)(dist >> 8);
byte b2 = (byte)(dist & 0xFF);
byte b3 = (byte)(findLen - 0x12);
temp[dstPos] = b1;
temp[dstPos + 1] = b2;
temp[dstPos + 2] = b3;
dstPos += 3;
}
srcPos += findLen;
}
//write data that does not need to be compressed
while (srcPos < src.Length)
{
if (cycle == 8)
{
opcodePos = dstPos;
dstPos++;
cycle = 0x00;
}
temp[opcodePos] = (byte)(temp[opcodePos] | 0x80 >> (int)cycle);
cycle++;
temp[dstPos] = src[srcPos];
dstPos++;
srcPos++;
}
writeLen = dstPos;
byte[] ret = new byte[writeLen + 0x10];
EndianBytesOperator.writeString(ret, 0, "Yaz0", 4);
EndianBytesOperator.writeUInt(ret, 0x04, (uint)src.Length);
for (int i = 0; i < writeLen; i++)
{
ret[i + 0x10] = temp[i];
}
return(ret);
}