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

# MQTT Server Parameters
MQTT_CLIENT_ID = "uni460-azkalufthansa"
MQTT_BROKER    = "broker.emqx.io"
MQTT_USER      = ""
MQTT_PASSWORD  = ""
MQTT_SENSOR_TOPIC = "/UNI460/azkalufthansa/data_sensor"
MQTT_LED_TOPIC = "/UNI460/azkalufthansa/aktuasi_led"

sensor1 = dht.DHT22(Pin(15))
sensor2 = dht.DHT22(Pin(2))

led = Pin(13, Pin.OUT)

# 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... ", end="")
client = MQTTClient(MQTT_CLIENT_ID, MQTT_BROKER, user=MQTT_USER, password=MQTT_PASSWORD)
client.connect()
print("Connected!")

# Callback funcion for Topic Subscription
def sub_cb(topic, msg):
  print(str(msg,'UTF-8'))
  if str(msg,'UTF-8') == "True":
    led.on()
  else:
    led.off()

client.set_callback(sub_cb)
client.subscribe(MQTT_LED_TOPIC)

# Build the message in JSON format and send the message only if there is a change
prev_weather = ""
while True:
  client.check_msg()

  # print("Measuring weather conditions... ", end="")
  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_SENSOR_TOPIC, message))
    # Send the message
    client.publish(MQTT_SENSOR_TOPIC, message)
    prev_weather = message
  else:
    print("No change")
  time.sleep(1)