import paho.mqtt.client as mqtt
import logging
import datetime
from collections import deque

from django.conf import settings

HOST = settings.MQTT_SETTINGS['HOST']
PORT = settings.MQTT_SETTINGS['PORT']
TOPICS = settings.MQTT_SETTINGS['TOPICS']
latest = {}


def on_connect(client, userdata, flags, rc):
    logging.info('Connected successfully to MQTT.')
    logging.info('Subscribing to all topics on {}.'.format(HOST))
    client.subscribe('sik/kiltahuone/kahvivaaka/#')


def update_latest(msg):
    payload = msg.payload.decode('utf-8')
    if msg.topic == TOPICS['WEIGHT']:
        weight = float(payload)
        latest['weight'] = weight
    elif msg.topic == TOPICS['CUPS']:
        cups = float(payload)
        latest['cups'] = cups
    elif msg.topic == TOPICS['BREWING']:
        brewing = bool(int(payload))
        latest['brewing'] = brewing
    elif msg.topic == TOPICS['BREW_TIME']:
        brew_time = datetime.datetime.fromtimestamp(float(payload))
        latest['brew_time'] = brew_time


def on_message(client, userdata, msg):
    try:
        update_latest(msg)
    except Exception as ex:
        logging.exception('Failed to parse MQTT payload.')


def on_disconnect(client, userdata, rc):
    if rc != 0:
        logging.warning('MQTT unexpectedly disconnected.')
    else:
        client.loop_stop(force=False)
        logging.warning('MQTT disconnected.')


def get_latest():
    return latest


client = mqtt.Client()
client.on_connect = on_connect
client.on_message = on_message
client.on_disconnect = on_disconnect