replace dd month dates with mmdd dates in filenames

ddmonth-mmdd.py

#!/usr/bin/env python3
#usage: python3 ddmonth-mmdd.py rootdir

import re
import os
from sys import argv

dtregexp = re.compile("(?P<d>\d\d?)\s?(?P<m>[A-Za-z]+)")
mleg = ["gennaio", "febbraio", "marzo", "aprile", "maggio", "giugno", "luglio", "agosto", "settembre", "ottobre", "novembre", "dicembre"]

def applyall(root):
    for rdir, sdirs, files in os.walk(root): 
        for f in files:
            chname(os.path.join(rdir, f))

def chname(fname):
    mt = re.search(dtregexp, fname)
    if not mt:
        print("%s NO"%fname)
        return 0
    dtstring = fname[mt.start():mt.end()]
    dct = mt.groupdict()
    try:
        os.rename(fname, fname.replace(dtstring, "%d%s"%(mleg.index(dct["m"].lower())+1, dct["d"].rjust(2, "0"))))
        print("%s OK"%fname)
    except ValueError:
        print("%s NO"%fname)

               
if __name__ == "__main__":
    try:
        applyall(argv[1])
    except IndexError:
        print("dir?")