#!/usr/bin/env python3
# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4

"""
This script records internet radio streams. It can be used in conjunction
with "at" or "crontab".
"""

import argparse
import configparser
import datetime
import os
import sys
import threading
import urllib.request

def check_duration(value):
    try:
        value = int(value)
    except ValueError:
        raise argparse.ArgumentTypeError('Duration must be a positive integer.')

    if value < 1:
        raise argparse.ArgumentTypeError('Duration must be a positive integer.')
    else:
        return value

def read_settings():
    settings_base_dir = ''
    if sys.platform == 'linux':
        settings_base_dir = os.getenv('HOME') + os.sep + '.config' + os.sep + 'radiorec'
    elif sys.platform == 'win32':
        settings_base_dir = os.getenv('APPDATA') + os.sep + 'radiorec'
    settings_base_dir += os.sep
    config = configparser.ConfigParser()
    config.read(settings_base_dir + 'settings.ini')
    return dict(config.items())

def record_worker(stoprec, streamurl, target_dir, name=None):
    conn = urllib.request.urlopen(streamurl)
    filename = target_dir + os.sep + datetime.datetime.now().isoformat()
    if name:
        filename += '_' + name
    content_type = conn.getheader('Content-Type')
    if(content_type == 'audio/mpeg'):
        filename += '.mp3'
    elif(content_type == 'application/ogg' or content_type == 'audio/ogg'):
        filename += '.ogg'
    else:
        print('Unknown content type. Assuming mp3.')
        filename += 'mp3'
    target = open(filename, "wb")
    while(not stoprec.is_set() and not conn.closed):
        target.write(conn.read(1024))

def record(args):
    settings = read_settings()
    streamurl = ''
    try:
        streamurl = settings['STATIONS'][args.station]
    except KeyError:
        print('Unkown station name: ' + args.station)
        return
    target_dir = os.path.expandvars(settings['GLOBAL']['target_dir'])
    stoprec = threading.Event()

    print('Recording ' + args.station + '…')
    recthread = threading.Thread(target = record_worker, 
                        args = (stoprec, streamurl, target_dir, args.name), daemon = True)
    recthread.start()
    recthread.join(args.duration * 60)

    if(recthread.is_alive):
        stoprec.set()

def list(args):
    settings = read_settings()
    print('Known stations:')
    for key in settings['STATIONS']:
        print(key)

def main():
    parser = argparse.ArgumentParser(prog='radiorec', description='This program records internet radio streams')
    subparsers = parser.add_subparsers(help='sub-command help')
    parser_record = subparsers.add_parser('record', help='Record a station')
    parser_record.add_argument('station', type=str, help='Name of the radio station '
                                               '(see config file for a list)')
    parser_record.add_argument('duration', type=check_duration, 
                        help='Recording time in minutes')
    parser_record.add_argument('name', nargs='?', type=str, 
                        help='A name for the recording')
    parser_record.set_defaults(func=record)
    parser_list = subparsers.add_parser('list', help='List all known stations')
    parser_list.set_defaults(func=list)
    #parser_list.add_argument('-l', '--list', action='store_true',
    #                    help='Get a list of all known radio stations')
    args = parser.parse_args()
    args.func(args)

if __name__ == '__main__':
    main()