'''
fakedj.py

This is a helper script that acts like the liquidsoap application. We make
RESTful requests are made on a set time to get the next song and to report
that the song has been played. This is useful for testing the radio without
having liquidsoap setup yet.
'''

import json
import logging
from logging.handlers import RotatingFileHandler
import signal
from threading import Event

from decouple import config
import requests

exit_ = Event()

DJ_TOKEN = config('DJ_TOKEN')

API_URL = config('API_URL')  # With trailing slash

RADIO_NAME = config('RADIO_NAME')

HEADERS = {
    'Content-Type': 'application/json; charset=utf-8',
    'Authorization': 'Token {}'.format(DJ_TOKEN)
}

ANNOTATE = (
    'annotate:req_id="{}",'
    'type="{}",'
    'artist="{}",'
    'title="{}",'
    'game="{}",'
    'replay_gain="{}":{}'
)

logging.basicConfig(
        handlers=[
            RotatingFileHandler(
                './song_requests.log',
                maxBytes=1000000,
                backupCount=5,
                encoding='utf8'
            )
        ],
        level=logging.INFO,
        format=('[%(asctime)s] [%(levelname)s]'
                ' [%(name)s.%(funcName)s] === %(message)s'),
        datefmt='%Y-%m-%dT%H:%M:%S'
    )
LOGGER = logging.getLogger('fakedj')


def clean_quotes(unclean_string):
    '''
    Escapes quotes for use in the Liquidsoap parser.
    '''
    return unclean_string.replace('"', '\\"')


def beautify_artists(artists):
    '''
    Turns a list of one or more artists into a proper English listing.
    '''
    output = ', '
    if len(artists) == 2:
        output = ' & '
    return clean_quotes(output.join(artists))


def next_request():
    '''
    Sends an HTTP[S] request to the radio web service to retrieve the next
    requested song.
    '''
    LOGGER.debug('Received command to get next song request.')
    try:
        resp = requests.get(API_URL + 'next/', headers=HEADERS, timeout=5)
        resp.encoding = 'utf-8'
        resp.raise_for_status()
    except requests.exceptions.HTTPError as errh:
        LOGGER.error('Http Error: %s', errh)
        return None
    except requests.exceptions.ConnectionError as errc:
        LOGGER.error('Error Connecting: %s', errc)
        return None
    except requests.exceptions.Timeout as errt:
        LOGGER.error('Timeout Error: %s', errt)
        return None
    except requests.exceptions.RequestException as err:
        LOGGER.error('Error: %s', err)
        return None
    else:
        LOGGER.debug('Received JSON response: %s', resp.text)
        song_request = json.loads(resp.text)
        song = song_request['song']
        if song['song_type'] == 'J':
            artist = RADIO_NAME
            title = 'Jingle'
            game = RADIO_NAME
        else:
            artist = beautify_artists(song['artists'])
            title = clean_quotes(song['title'])
            game = clean_quotes(song['game'])
        LOGGER.info(
            'ID: %s, Artist[s]: %s, Title: %s, Game: %s, Gain: %s, Path: %s',
            song_request['id'],
            artist,
            title,
            game,
            song['replaygain'],
            song['path']
        )
        annotate_string = ANNOTATE.format(
            song_request['id'],
            song['song_type'],
            artist,
            title,
            game,
            song['replaygain'],
            song['path']
        )
        LOGGER.debug(annotate_string)
        return song_request


def just_played(request_id):
    '''
    Sends an HTTP[S] request to the radio web service to let it know that a
    song has been played.
    '''
    LOGGER.debug('Received command to report a song was just played.')
    try:
        request_played = json.dumps({'song_request': request_id})
        resp = requests.post(
            API_URL + 'played/',
            headers=HEADERS,
            data=request_played,
            timeout=5
        )
        resp.encoding = 'utf-8'
        resp.raise_for_status()
    except requests.exceptions.HTTPError as errh:
        LOGGER.error('Http Error: %s', errh)
    except requests.exceptions.ConnectionError as errc:
        LOGGER.error('Error Connecting: %s', errc)
    except requests.exceptions.Timeout as errt:
        LOGGER.error('Timeout Error: %s', errt)
    except requests.exceptions.RequestException as err:
        LOGGER.error('Error: %s', err)
    else:
        LOGGER.info('Req_ID: %s', request_id)


def main():
    '''Main loop of the program'''
    while not exit_.is_set():
        next_req = next_request()
        exit_.wait(2)
        just_played(next_req['id'])
        exit_.wait(10)

    print("FakeDJ exiting!")


def quit_(signo, _frame):
    print("Interrupted by {}, shutting down".format(str(signo)))
    exit_.set()


if __name__ == '__main__':
    for sig in ('TERM', 'HUP', 'INT'):
        signal.signal(getattr(signal, 'SIG'+sig), quit_)
    main()