import os
import argparse
from PIL import Image
from tqdm import tqdm
from pathlib import Path


def run(src: Path, target: Path, root: Path, scale_factor: float = 1., width: int = -1, height: int = -1):
    target.mkdir(exist_ok=True)
    for file_name in tqdm(os.listdir(src), leave=False, desc=src.relative_to(root).__str__()):
        if (src / file_name).is_dir():
            run(src / file_name, target / file_name, root, scale_factor, width, height)
        elif not (target / file_name).exists():
            postfix = os.path.splitext(file_name)[1]
            if postfix == '.jpg' or postfix == '.png':
                im = Image.open(src / file_name)
                if width == -1 and height == -1:
                    width = round(im.width * scale_factor)
                    height = round(im.height * scale_factor)
                elif width == -1:
                    width = round(im.width / im.height * height)
                elif height == -1:
                    height = round(im.height / im.width * width)
                im = im.resize((width, height))
                im.save(target / file_name)


if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument('src', type=str,
                        help='Source directory.')
    parser.add_argument('target', type=str,
                        help='Target directory.')
    parser.add_argument('-x', '--scale-factor', type=float, default=1,
                        help='Target directory.')
    parser.add_argument('--width', type=int, default=-1,
                        help='Width of output images (pixel)')
    parser.add_argument('--height', type=int, default=-1,
                        help='Height of output images (pixel)')
    opt = parser.parse_args()
    run(Path(opt.src), Path(opt.target), Path(opt.src), opt.scale_factor, opt.width, opt.height)