#!/usr/bin/env python3
import glob
import gzip
import logging
import multiprocessing
import os
import re
import sys

MODDATE_RE=re.compile("\s*<LastModDate Value=\"(\d+)\".")

def update_times(als):
    try:
        largest_timestamp = 0
        with gzip.open(als, 'rb') as xml_file:
            xml = xml_file.read()
            for timestamp in MODDATE_RE.findall(str(xml), re.DOTALL):
                timestamp = int(timestamp)
                if timestamp > largest_timestamp:
                    largest_timestamp = timestamp
        if largest_timestamp > 0:
            os.utime(als, times=(largest_timestamp, largest_timestamp))
    except:
        logging.error("ERROR: {}".format(als))
    return 0

with multiprocessing.Pool(processes=16) as pool:
    pool.map(update_times,
             glob.iglob("{}/**/*.als".format(sys.argv[1]), recursive=True))