LZ Decompressors for CGX files (LZ19 and LZ3)

# Some CGX files are LZ19, and some are LZ3. you have to try both

bit_flipped = [
    sum(((byte >> i) & 1) << (7 - i) for i in range(8))
    for byte in range(0x100)
]
def lc_lz19_Decompress(lz):

    addr = 0
    output = []

    while lz[addr] != 0xFF:

        cmd = lz[addr] >> 5

        if cmd == 7:
            cmd = (lz[addr] >> 2) & 0x7
            length = (lz[addr] & 0x3)*0x100 + lz[addr+1] + 1
            addr += 2
        else:
            length = (lz[addr] & 0x1F) + 1
            addr += 1

        if cmd==0:
            output += lz[addr:addr+length]
            addr += length
        elif cmd==1:
            val = lz[addr]
            addr += 1
            output += [val] * length
        elif cmd==2:
            val1 = lz[addr]
            addr += 1
            val2 = lz[addr]
            addr += 1
            output += [val1, val2] * length
        elif cmd==3:
            val = lz[addr]
            addr += 1
            for i in range(length):
                output += [(val+i)%256]
        elif cmd==4:
            outbuf_addr = lz[addr]*0x100 + lz[addr+1]
            addr += 2
            for i in range(length):
                output.append(output[outbuf_addr+i])
        elif cmd==5:
            outbuf_addr = lz[addr]*0x100 + lz[addr+1]
            addr += 2
            for i in range(length):
                output.append(bit_flipped[output[outbuf_addr+i]])
        elif cmd==6:
            outbuf_addr = lz[addr]*0x100 + lz[addr+1]
            addr += 2
            for i in range(length):
                output.append(output[outbuf_addr-i])
        else:
            print('unimplemented cmd '+str(cmd))
            1/0

    return output

def lc_lz3_Decompress(lz):

    addr = 0
    output = []

    while lz[addr] != 0xFF:

        cmd = lz[addr] >> 5

        if cmd == 7:
            cmd = (lz[addr] >> 2) & 0x7
            length = (lz[addr] & 0x3)*0x100 + lz[addr+1] + 1
            addr += 2
        else:
            length = (lz[addr] & 0x1F) + 1
            addr += 1

        if cmd==0:
            output += lz[addr:addr+length]
            addr += length
        elif cmd==1:
            val = lz[addr]
            addr += 1
            output += [val] * length
        elif cmd==2:
            vals = (lz[addr], lz[addr+1])
            addr += 2
            for i in range(length):
                output.append(vals[i%2])
        elif cmd==3:
            output += [0] * length
        elif cmd==4:
            if lz[addr] & 0x80:
                outbuf_addr = len(output) - 1 - (lz[addr]&0x7F)
                addr += 1
            else:
                outbuf_addr = lz[addr]*0x100 + lz[addr+1]
                addr += 2
            for i in range(length):
                output.append(output[outbuf_addr+i])
        elif cmd==5:
            if lz[addr] & 0x80:
                outbuf_addr = len(output) - 1 - (lz[addr]&0x7F)
                addr += 1
            else:
                outbuf_addr = lz[addr]*0x100 + lz[addr+1]
                addr += 2
            for i in range(length):
                output.append(bit_flipped[output[outbuf_addr+i]])
        elif cmd==6:
            if lz[addr] & 0x80:
                outbuf_addr = len(output) - 1 - (lz[addr]&0x7F)
                addr += 1
            else:
                outbuf_addr = lz[addr]*0x100 + lz[addr+1]
                addr += 2
            for i in range(length):
                output.append(output[outbuf_addr-i])
        else:
            print('unimplemented cmd '+str(cmd))
            1/0

    return output

def convertTxt(filename):
    print(filename)
    ret = []
    f=open(filename,'r')
    ignore_mode = False

    width=0
    height=0
    first_len = 0
    len_sum = 0
    prev_len = 0

    width_solved = False
    needsCommon = False

    for line in f:
        if 'ifn' in line:
            ignore_mode = True
        elif 'else' in line or 'endif' in line:
            ignore_mode = False
        elif not ignore_mode:
            if '\tdb' in line:
                words=re.sub(r';.*','',line).replace('\tdb','').strip().strip(',').split(',')
                if len(words) > 0 and not width_solved:
                    if first_len == 0:
                        first_len = len(words)
                        width = len(words)
                        if ';20' in line:
                            needsCommon = True
                    elif first_len == len(words) and prev_len != len(words):
                        width = len_sum
                        width_solved = True
                    len_sum += len(words)
                    prev_len = len(words)
                for word in words:
                    word=word.strip()
                    if word[0]!='0':
                        print(word, word[0])
                    assert word[0]=='0'
                    assert word[-1]=='h'
                    if len(word) == 4:
                        ret.append(int(word[1:3], 16))
                    elif len(word) == 6:
                        1/0
                        ret.append(int(word[1:3], 16))
                        ret.append(int(word[3:5], 16))
                    else:
                        1/0
            elif '\tdw' in line:
                words=re.sub(r';.*','',line).replace('\tdw','').strip().strip(',').split(',')
                for word in words:
                    word=word.strip()
                    if len(word) == 5:
                        word = '0'+word
                    assert word[0]=='0'
                    assert word[-1]=='h'
                    if len(word) == 6:
                        ret.append(int(word[3:5], 16))
                        ret.append(int(word[1:3], 16))
                    else:
                        1/0
            elif '\tdh' in line:
                1/0 #todo
    f.close()
    if width != 0:
        height = len(ret)//width

    if '.CGX' in filename:
        ret_lz19 = lc_lz19_Decompress(ret)

        if len(ret_lz19)%0x100 == 0:
            ret = ret_lz19
        else:
            ret_lz3 = lc_lz3_Decompress(ret)

            if len(ret_lz3)%0x100 == 0:
                ret = ret_lz3
            else:
                1/0

        f2=open('temp_'+filename.split('/')[-1]+'.2bpp','wb')
        f2.write(bytearray(ret))
        f2.close()

    return ret, width, height, needsCommon