import sys; sys.dont_write_bytecode = True
import os
from pathlib import Path
import time

import argparse
import requests

from common import *

API_PART = ['snippet','contentDetails','status','statistics','player',
            'topicDetails','recordingDetails','liveStreamingDetails',
            'localizations']
MAX_RESULTS = 50
API_PARAMS = {'part': ','.join(API_PART)}

## Parse arguments
def __parse_args(argv):

    parser = argparse.ArgumentParser(
        description='Write video metadata.',
        formatter_class=argparse.RawTextHelpFormatter)
    parser._action_groups.pop()
    required = parser.add_argument_group('required arguments')
    optional = parser.add_argument_group('optional arguments')
    required.add_argument(
        '-i','--input',required=True,
        help='List of videoIds (https://www.youtube.com/watch?v={videoId})',
        metavar='videos.txt')
    optional.add_argument(
        '-d','--api_dir', type=Path,
        default=Path(__file__).absolute().parent / 'videos',
        help='Output directory for API files. Default is ./videos.',
        metavar='./videos')
    
    args = parser.parse_args(argv)
    f_in = args.input
    api_dir = args.api_dir
    if not f_in.endswith('.txt'):
        raise ValueError('Input filename not a .txt file.')

    return {'input':f_in,'api_dir':api_dir}

    
def main(args):

	## Create error logger
    err_log = make_error_logger('error.log')

    ## Parse arguments
    args = __parse_args(args)
    f_in = args['input']
    api_dir = args['api_dir']

    ## Get Ids from input file
    ids_in = get_ids(f_in,'videoId')

    ## Create output directory
    if not os.path.exists(api_dir):
        os.makedirs(api_dir)

    ## Split videoIDs into groups of MAX_RESULTS
    id_lists = [
        ids_in[i:i+MAX_RESULTS] for i in range(0,len(ids_in),MAX_RESULTS)]
    
    ## Iterate over Ids
    session = requests.Session()
    session.params = API_PARAMS
    total_ids = len(ids_in)
    for i,id_list in enumerate(id_lists):
        
        print('\n########################\n')
        lower = i*MAX_RESULTS
        upper = min((i+1)*MAX_RESULTS,total_ids)
        print('Processing {} Ids ({}/{})...'.format(
                upper-lower,upper,total_ids))

        ## Get API info
        session.params['id'] = ','.join(id_list)
        ret = get_api_items('videos',session)
        (js,session,err_msg) = (ret['json'],ret['session'],ret['error'])
        if err_msg:
            err_log.error(f'Ids {lower}/{upper}: {err_msg}')
            time.sleep(1)
            continue

        ## Write API info to file
        print(f'Writing API info to {api_dir}...')
        for item in js:
            f_api = os.path.join(api_dir, '{}_info.json'.format(item['id']))
            try:
                write_api(f_api, item)
            except Exception as e:
                err_log.error('{}: {}'.format(item['id'],e))
        print('Write successful.')

    return


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