radio

#!/usr/bin/env python2
# -*- coding: utf-8 -*-
from __future__ import print_function

import itertools as it, operator as op, functools as ft
from tempfile import NamedTemporaryFile
import os, sys, io, re, requests, yaml, subprocess, signal, logging


player_wrap = 'media.mpv_icy_track_history' # should be in the sampe repo
tracks_global = os.path.expanduser('~/tracks.txt')

# --no-cache to prevent any audio/meta de-sync, so mute would work nicely
# Alternative: '--cache=1024', '--cache-initial=0'
mpv_args_base = ['--shuffle', '--loop=inf', '--no-cache', '--vo=null']

# radios_conf example (yaml):
#   rmnrelax:
#     url_pls: 'http://www.rmnrelax.de/aacplus/rmnrelax.m3u'
#     args_wrapper: ['--mute-regexp=^\[RMN\]', '--recode-from=latin-1']
#   etnfm:
#     url_pls: 'http://ch1relay1.etn.fm:8100/listen.pls?sid=1'
#   soma:
#     template: true
#     url_pls: 'http://somafm.com/{}.pls'
#   difm:
#     # use as e.g. "difm.vocaltrance" (to template "vocaltrance" into urls)
#     template: true
#     #url_pls: 'http://listen.di.fm/public3/{}.pls?3e4c569'
#     url: 'http://pub5.di.fm:80/di_{}?3e4c569'
#     args_wrapper:
#       - >
#         --mute-regexp=^(There|More of the show after these messages|Choose
#         premium for the best audio experience|Digitally Imported TSTAG_60 ADWTAG|Job
#         Opportunity at DI!.*|There's more to Digitally Imported!)$
#       - --mute-title-prefix
radios_conf_default = '~/.radio.yaml'


_notify_init = False
def notify(title, body, critical=False, timeout=None, icon=None, fork=True):
	global _notify_init
	if fork and os.fork(): return
	try:
		import gi
		gi.require_version('Notify', '0.7')
		from gi.repository import Notify
		if not _notify_init:
			Notify.init('radio')
			_notify_init = True
		note = Notify.Notification.new(summary=title, body=body, icon=icon)
		if critical: note.set_urgency(Notify.Urgency.CRITICAL)
		if timeout is not None: note.set_timeout(timeout)
		note.show()
	except: pass
	if fork: os._exit(0)

def no_such_chan(err, chans):
	p = ft.partial(print, file=sys.stderr)
	p(err)
	p('\nPossible matches:')
	for chan in chans: p('  ' + chan)
	sys.exit(1)

def get_url(chan, pls=False):
	url = chan.get('url' if not pls else 'url_pls')
	if url and chan.get('template'):
		assert re.search(r'\{(\d+(:.*)?)?\}', url), url
		name = chan['name'].split('.', 1)[-1]
		url = url.format(name)
	return url

def main(args=None):
	import argparse
	parser = argparse.ArgumentParser(description='Start radio playback.')
	parser.add_argument('chan',
		help='Radio channel (exact name or unique part of it) to tune into.')
	parser.add_argument('-c', '--conf',
		metavar='path', default=radios_conf_default,
		help='Path to the configuration file with a list of radios.'
			' See head of this script for an example. Default: %(default)s')
	parser.add_argument('--desktop-notification-props',
		default='{fork: false, icon: amarok, critical: true}', metavar='yaml_data',
		help='Desktop notification properties (keywords) to pass to notify() function (see code).'
			' "false" (bool value) can be passed here to disable desktop notifications entirely.'
			' Default: %(default)s')
	parser.add_argument('--debug', action='store_true', help='Verbose operation mode.')
	opts = parser.parse_args(sys.argv[1:] if args is None else args)

	logging.basicConfig(level=logging.DEBUG if opts.debug else logging.WARNING)
	log = logging.getLogger('radio')

	files_cleanup = set()
	radios = os.path.expanduser(opts.conf)
	with io.open(radios) as src: radios = yaml.safe_load(src)

	chan = chan_name = opts.chan
	if chan not in radios:
		match = list(k for k in radios if k.startswith(chan))
		if not match:
			chan_tpl_base = chan.split('.', 1)[0]
			match = radios.get(chan_tpl_base)
			if match: match = match.get('template') and [chan_tpl_base]
		if not match: match = list(k for k in radios if chan in k)
		if not match: no_such_chan('Unable to match {!r}'.format(chan), radios.keys())
		if len(match) > 1: no_such_chan('Unable to uniquely match {!r}'.format(chan), match)
		chan, = match

	log.debug('Using chan: %s', chan)
	chan = radios[chan]
	chan.update(name=chan_name)

	url = get_url(chan, pls=True)
	if url:
		r = requests.get(url)
		r.raise_for_status()
		pls = NamedTemporaryFile(prefix='radio.pls.') # will be cleaned-up by child pid
		files_cleanup.add(pls.name)
		pls.write(r.text)
		pls.flush()
		url = '--playlist={}'.format(pls.name)
	else:
		url = get_url(chan)
		assert url, chan

	tracks = tracks_global
	if 'tracks' in chan: tracks = chan['tracks']
	if not os.path.exists(tracks):
		with open(tracks, 'ab'): pass

	notify_kws = yaml.safe_load(opts.desktop_notification_props)
	if notify_kws is not False: notify_kws = notify_kws or dict()

	pid_player = os.getpid()
	pid = os.fork()
	if not pid: ### child
		os.setsid()

		tail = subprocess.Popen(['tail', '-n1', '-f', tracks], stdout=subprocess.PIPE)

		def player_check(sig=None, frm=None):
			try: os.kill(pid_player, 0)
			except OSError:
				tail.terminate()
				sys.exit(0)
		signal.signal(signal.SIGALRM, player_check)
		signal.alarm(5 *60)

		for line in iter(tail.stdout.readline, ''):
			player_check()
			line = line.strip()
			if notify_kws is not False:
				notify('mpv: radio {}'.format(chan['name']), line, **notify_kws)
			print(line)

		sys.exit(0)

	else: ### parent (player)
		args_wrapper, args = chan.get('args_wrapper', list()), chan.get('args', list())
		args = mpv_args_base + args

		if opts.debug: args_wrapper.extend(['--debug', '--passthrough'])
		if tracks: args_wrapper.extend([ '-d', tracks, '-t',
			'--line-format', '{{ts}}{{mute}}{{}} [{}]\n'.format(chan['name']) ])
		args.append(url)

		args = [player_wrap] + args_wrapper + ['--'] + args
		log.debug('Running: %s', ' '.join(args))
		os.execvp(player_wrap, args)

if __name__ == '__main__': sys.exit(main())