import datetime
import logging

import paho.mqtt.client as mqtt
import slugify
from django.conf import settings

from . import models

log = logging.getLogger(__name__)


class MQTTClient:
    def __init__(self):
        self.reconnect = True
        self.connected = False

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

    def loop_forever(self):
        self.connect()
        self.client.loop_forever()

    def loop_start(self):
        self.connect()
        self.client.loop_start()

    def loop_stop(self):
        self.disconnect(reconnect=False)
        self.client.loop_stop()

    def connect(self):
        try:
            self.client.connect(
                settings.MQTT_SERVER,
                settings.MQTT_PORT,
                60,  # TODO: make the keepalive configurable
            )
        except OSError as e:
            log.warning("Could not connect to MQTT server")
            log.warning(e)

    def disconnect(self, reconnect: bool = True):
        self.reconnect = reconnect
        self.client.disconnect()

    def on_connect(self, client, userdata, flags, rc):
        log.info("Connected to MQTT")
        self.connected = True
        client.subscribe(settings.MQTT_TOPIC + "#")

    def on_disconnect(self, client, userdata, rc):
        log.info("Disconnected from MQTT")
        self.connected = False
        if self.reconnect:
            self.connect()

    def on_message(self, client, userdata, msg):
        log.debug(
            "Received msg %s %s", msg.topic, msg.payload.decode()
        )
        ts = int(datetime.datetime.now().timestamp())
        topic = msg.topic.removeprefix(settings.MQTT_TOPIC)
        dss = models.DataSource.objects.filter(topic=topic)
        if not dss:
            dss = (models.DataSource.objects.create(
                topic=topic,
                path=slugify.slugify(topic) + ".rrd",
            ),)
        for ds in dss:
            ds.update(ts, msg.payload.decode())