import time

from machine import Pin
from umqtt.simple import MQTTClient

client = MQTTClient("alarm", "serverip", port=1883, user="username",
                    password="password")

client.connect()


class Sensor:
    def __init__(self, pin_num, name):
        self.pin = Pin(pin_num, Pin.IN, Pin.PULL_UP)
        self.last_value = None
        self.name = name

    @property
    def value(self):
        return self.pin.value()

    def update_last(self):
        self.last_value = self.value

    @property
    def has_changed(self):
        if self.last_value != self.value:
            self.update_last()
            return True

sensors = [Sensor(5, "backdoor"), Sensor(4, "frontdoor"),
           Sensor(0, "kitchen")]

while True:
    for sensor in sensors:
        if sensor.has_changed:
            if sensor.last_value:
                print("{} on".format(sensor.name))
                client.publish("alarm/{}".format(sensor.name), "on")
            else:
                print("{} off".format(sensor.name))
                client.publish("alarm/{}".format(sensor.name), "off")
    time.sleep(0.1)