public Inflater(bool nowrap)
{
this.nowrap = nowrap;
this.adler = new Adler32();
this.input = new StreamManipulator();
this.outputWindow = new OutputWindow();
this.mode = nowrap ? 2 : 0;
}
public int GetSymbol(StreamManipulator input)
{
int num2;
int index = input.PeekBits(9);
if (index >= 0)
{
num2 = this.tree[index];
if (num2 >= 0)
{
input.DropBits(num2 & 15);
return (num2 >> 4);
}
int num3 = -(num2 >> 4);
int n = num2 & 15;
index = input.PeekBits(n);
if (index >= 0)
{
num2 = this.tree[num3 | (index >> 9)];
input.DropBits(num2 & 15);
return (num2 >> 4);
}
int num5 = input.AvailableBits;
index = input.PeekBits(num5);
num2 = this.tree[num3 | (index >> 9)];
if ((num2 & 15) <= num5)
{
input.DropBits(num2 & 15);
return (num2 >> 4);
}
return -1;
}
int availableBits = input.AvailableBits;
index = input.PeekBits(availableBits);
num2 = this.tree[index];
if ((num2 >= 0) && ((num2 & 15) <= availableBits))
{
input.DropBits(num2 & 15);
return (num2 >> 4);
}
return -1;
}
public int CopyStored(StreamManipulator input, int len)
{
int num;
len = Math.Min(Math.Min(len, WINDOW_SIZE - this.window_filled), input.AvailableBytes);
int length = WINDOW_SIZE - this.window_end;
if (len > length)
{
num = input.CopyBytes(this.window, this.window_end, length);
if (num == length)
{
num += input.CopyBytes(this.window, 0, len - length);
}
}
else
{
num = input.CopyBytes(this.window, this.window_end, len);
}
this.window_end = (this.window_end + num) & WINDOW_MASK;
this.window_filled += num;
return num;
}
public bool Decode(StreamManipulator input)
{
int num2;
int num3;
Label_0005:
switch (this.mode)
{
case 0:
this.lnum = input.PeekBits(5);
if (this.lnum >= 0)
{
this.lnum += 0x101;
input.DropBits(5);
this.mode = 1;
break;
}
return false;
case 1:
break;
case 2:
goto Label_00D1;
case 3:
goto Label_0161;
case 4:
goto Label_01D6;
case 5:
goto Label_0224;
default:
goto Label_0005;
}
this.dnum = input.PeekBits(5);
if (this.dnum < 0)
{
return false;
}
this.dnum++;
input.DropBits(5);
this.num = this.lnum + this.dnum;
this.litdistLens = new byte[this.num];
this.mode = 2;
Label_00D1:
this.blnum = input.PeekBits(4);
if (this.blnum < 0)
{
return false;
}
this.blnum += 4;
input.DropBits(4);
this.blLens = new byte[0x13];
this.ptr = 0;
this.mode = 3;
Label_0161:
while (this.ptr < this.blnum)
{
int num = input.PeekBits(3);
if (num < 0)
{
return false;
}
input.DropBits(3);
this.blLens[BL_ORDER[this.ptr]] = (byte) num;
this.ptr++;
}
this.blTree = new InflaterHuffmanTree(this.blLens);
this.blLens = null;
this.ptr = 0;
this.mode = 4;
Label_01D6:
while (((num2 = this.blTree.GetSymbol(input)) & -16) == 0)
{
this.litdistLens[this.ptr++] = this.lastLen = (byte) num2;
if (this.ptr == this.num)
{
return true;
}
}
if (num2 < 0)
{
return false;
}
if (num2 >= 0x11)
{
this.lastLen = 0;
}
else if (this.ptr == 0)
{
throw new Exception();
}
this.repSymbol = num2 - 0x10;
this.mode = 5;
Label_0224:
num3 = repBits[this.repSymbol];
int num4 = input.PeekBits(num3);
if (num4 < 0)
{
return false;
}
input.DropBits(num3);
num4 += repMin[this.repSymbol];
if ((this.ptr + num4) > this.num)
{
throw new Exception();
}
while (num4-- > 0)
{
this.litdistLens[this.ptr++] = this.lastLen;
}
if (this.ptr == this.num)
{
return true;
}
this.mode = 4;
goto Label_0005;
}
