#!/usr/bin/env python

import os
import random
import sys

from PIL import Image


def load_image(filename):
    image = Image.open(filename)
    print filename, image
    return image


def main(argv):
    if argv[1] == 'largest':
        greatest = 0
        greatest_filename = 'NONE'
        for filename in argv[2:]:
            image = load_image(filename)
            size = image.size[0] * image.size[1]
            if size > greatest:
                greatest = size
                greatest_filename = filename
        print "LARGEST IS", greatest_filename

    elif argv[1] == 'cutup':
        base_filename = argv[2]
        cutup_filenames = argv[3:]

        base_image = load_image(base_filename)
        base_width = base_image.size[0]
        base_height = base_image.size[1]

        images = []
        for filename in cutup_filenames:
            images.append(load_image(filename))

        for n in xrange(0, 100):
            image = random.choice(images)
            width = image.size[0]
            height = image.size[1]
            
            crop_width = width / 3
            crop_height = height / 3

            # note that for crop boxes, the 3rd and 4th elements are
            # *positions*, not *dimensions*!
            crop_x = random.randint(0, width - crop_width)
            crop_y = random.randint(0, height - crop_height)
            crop_box = (
                crop_x, crop_y, crop_x + crop_width, crop_y + crop_height
            )
            crop_region = image.crop(crop_box)
            print image, crop_box, crop_region

            paste_point = (random.randint(0, base_width - crop_width),
                           random.randint(0, base_height - crop_height))
            
            base_image.paste(crop_region, paste_point)
        
        print "Writing output.png..."
        base_image.save("output.png")

    else:
        raise KeyError("First arg must be `largest` or `cutup`")


if __name__ == '__main__':
    import sys
    main(sys.argv)