import atexit
import json
from datetime import datetime
from threading import Thread
from urllib.request import Request, urlopen

_format = '%Y-%m-%d %H:%M:%S.%f'
_file = None
_run_name = None
_slack_url = None


def init(filename, run_name, slack_url=None):
	global _file, _run_name, _slack_url
	_close_logfile()
	_file = open(filename, 'a')
	_file = open(filename, 'a')
	_file.write('\n-----------------------------------------------------------------\n')
	_file.write('Starting new {} training run\n'.format(run_name))
	_file.write('-----------------------------------------------------------------\n')
	_run_name = run_name
	_slack_url = slack_url


def log(msg, end='\n', slack=False):
	print(msg, end=end)
	if _file is not None:
		_file.write('[%s]  %s\n' % (datetime.now().strftime(_format)[:-3], msg))
	if slack and _slack_url is not None:
		Thread(target=_send_slack, args=(msg,)).start()


def _close_logfile():
	global _file
	if _file is not None:
		_file.close()
		_file = None


def _send_slack(msg):
	req = Request(_slack_url)
	req.add_header('Content-Type', 'application/json')
	urlopen(req, json.dumps({
		'username': 'tacotron',
		'icon_emoji': ':taco:',
		'text': '*%s*: %s' % (_run_name, msg)
	}).encode())


atexit.register(_close_logfile)