'''
I was having trouble making my Flask server perform the youtube-dl without
clogging up the other site activities. So instead I'll just have the server
export ytqueue files, which this script will download as a separate process.

Rather than maintaining a text file or database of IDs to be downloaded,
I'm fine with creating each ID as a file and letting the filesystem act
as the to-do list.
'''

import argparse
import os
import sys
import time

YOUTUBE_DL = 'youtube-dlw https://www.youtube.com/watch?v={id}'

def ytqueue(only_once=False):
    while True:
        print(time.strftime('%H:%M:%S'), 'Looking for files.')
        queue = [f for f in os.listdir() if f.endswith('.ytqueue')]
        for filename in queue:
            yt_id = filename.split('.')[0]
            command = YOUTUBE_DL.format(id=yt_id)
            exit_code = os.system(command)
            if exit_code == 0:
                os.remove(filename)
        if only_once:
            break
        time.sleep(10)

def ytqueue_argparse(args):
    return ytqueue(only_once=args.once)

def main(argv):
    parser = argparse.ArgumentParser()

    parser.add_argument('--once', dest='once', action='store_true')
    parser.set_defaults(func=ytqueue_argparse)

    args = parser.parse_args(argv)
    args.func(args)

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