#!/usr/bin/env python3
# -*- coding: utf8 -*-

from PIL import Image
import sys

# check if filename is present
if len(sys.argv) == 1:
    sys.exit("error: no filename spcified") 
f = sys.argv[1]

# open, crop and overwrite image
print(f"cropping file {f} … ", end='')
with Image.open(f) as i:
    # do nothing if size and bbox are equivalent
    bbox = i.getbbox()
    if bbox[0] == 0 and bbox[1] == 0 and bbox[2] == i.size[0] and bbox[3] == i.size[1]:
        print("nothing to do")
        sys.exit(0)
    
    i.crop(i.getbbox()).save(f)

print("successful")