import lz4.block
import struct

INPUT_FILE_NAME = 'Hammer.lua'
OUTPUT_FILE_NAME = 'Hammer.out.lua'

with open(INPUT_FILE_NAME, 'rb') as f:
    data = f.read()

header = data[:16]
payload = data[16:]

magic, outsize = struct.unpack('4sl8x', header)

if (magic != 'LZ4 '):
    print "Invalid format"
    exit(1)

if (outsize <= 0):
    print "Invalid ousize"
    exit(1)

unpacked = lz4.block.decompress(payload, outsize)

with open(OUTPUT_FILE_NAME, 'wb') as f:
    f.write(unpacked)
    print "Wrote %d bytes to file %s." % (outsize, OUTPUT_FILE_NAME)