#!/usr/bin/env python3

import glob
import os
import pprint  # pylint: disable=unused-import
import sys

from PIL import Image


TRANSPARENT_RGBA = (255, 255, 255, 0)


def main(args):
  if len(args) < 2:
    print('usage: python3 import_ccg.py CCG_ROOT Sprite_Name\n')
    print('Add an additional OUTPUT_ROOT argument to actually write output.')
    print('(Otherwise, this script just will perform a dry run.)')
    return

  ccg_root, sprite_name = args[:2]
  os.chdir(ccg_root)
  output_root = None
  if len(args) > 2:
    output_root = os.path.join(os.path.expanduser(args[2]), sprite_name)
    os.makedirs(output_root, exist_ok=True)

  sprite_files = sorted(glob.glob(sprite_name + '/*.png'))
  print('sprites: %d' % (len(sprite_files)))

  if not sprite_files:
    print('no sprite files found!')
    return

  # Collect sizes.
  max_width = 0
  max_height = 0
  for sprite in sprite_files:
    with Image.open(sprite) as image:
      max_width = max(max_width, image.width)
      max_height = max(max_height, image.height)
  new_size = (max_width, max_height)
  print('new size: %dx%d' % new_size)

  # Now frob them.
  for i, sprite in enumerate(sprite_files):
    with Image.open(sprite) as image:
      top_pad = max_height - image.height
      left_pad = (max_width - image.width) // 2
      right_pad = max_width - image.width - left_pad
      out_filename = '%s_%03d.png' % (sprite_name, i)
      print('%03d: %3dx%-3d top: %2d left: %2d right: %2d %s -> %s' % (
          i, image.width, image.height, top_pad, left_pad, right_pad, sprite,
          out_filename))
      if output_root:
        new_image = Image.new('RGBA', new_size, TRANSPARENT_RGBA)
        new_image.paste(image, (left_pad, top_pad))
        new_image.save(os.path.join(output_root, out_filename))


if __name__ == '__main__':
  main(sys.argv[1:])