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

# MQTT Server Parameters
MQTT_CLIENT_ID = "demoErick"
MQTT_BROKER    = "mqtt-dashboard.com"
MQTT_USER      = ""
MQTT_PASSWORD  = ""
MQTT_TOPIC     = "iotunam"

sensor1 = dht.DHT22(Pin(12))
sensor2 = dht.DHT22(Pin(14))

# WIFI Connection
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!")

# MQTT Server connection
print("Connecting to MQTT server... ")
client = MQTTClient(MQTT_CLIENT_ID, MQTT_BROKER, user=MQTT_USER, password=MQTT_PASSWORD)
client.connect()
print("Connected!")

# Build the message in JSON format and send the message only if there is a change
prev_weather = ""
while True:
  print("Measuring weather conditions... ")
  sensor1.measure() 
  sensor2.measure() 
  message = ujson.dumps({
    "temp1": sensor1.temperature(),
    "humidity1": sensor1.humidity(),
    "temp2": sensor2.temperature(),
    "humidity2": sensor2.humidity(),
  })
  if message != prev_weather:
    print("Updated!")
    print("Reporting to MQTT topic {}: {}".format(MQTT_TOPIC, message))
    # Send the message
    client.publish(MQTT_TOPIC, message)
    prev_weather = message
  else:
    print("No change")
  time.sleep(1)