import network
import time
from machine import Pin
import dht
import ujson
from umqtt.simple import MQTTClient

# MQTT Server Parameters
MQTT_CLIENT_ID = "micropython-weather-demo"
MQTT_BROKER    = "broker.mqttdashboard.com"
MQTT_USER      = ""
MQTT_PASSWORD  = ""
MQTT_TOPIC     = "wokwi-weather1"

sensor = dht.DHT22(Pin(15))
led = Pin(2, Pin.OUT)

def sub_cb(topic, msg):
    global state
    print((topic, msg))
    if msg == b"on":
        led.value(1)
        state = 1
    elif msg == b"off":
        led.value(0)
        state = 0


print("Connecting to WiFi", end="")
sta_if = network.WLAN(network.STA_IF)
sta_if.active(True)
sta_if.connect('Wokwi-GUEST', '')
while not sta_if.isconnected():
  print(".", end="")
  time.sleep(0.1)
print(" Connected!")



print("Connecting to MQTT server... ", end="")
client = MQTTClient(MQTT_CLIENT_ID, MQTT_BROKER, user=MQTT_USER, password=MQTT_PASSWORD)
client.set_callback(sub_cb)
client.connect()



print("Connected!")

prev_weather = ""

while True:
  #print("Measuring weather conditions... ", end="")
  sensor.measure() 

  message = ujson.dumps([
    sensor.temperature(), sensor.humidity()
  ])
  if message != prev_weather:
    print("Updated!")
    print("Reporting to MQTT topic {}: {}".format(MQTT_TOPIC, message))
    client.publish(MQTT_TOPIC, message)
    prev_weather = message
  else:
    print("No change")
  
  time.sleep(1)

  client.subscribe(MQTT_TOPIC)