from machine import Pin
import network
import time
from umqtt.simple import MQTTClient
import dht
# asynchronous processing library
import uasyncio as asyncio

sta=network.WLAN(network.STA_IF)
sta.active(True)   
sta.connect('Wokwi-GUEST','')
print('Linking...')
while not sta.isconnected() :
    pass
print('Link OK')

dht22 = dht.DHT22(Pin(15, Pin.IN))

def handle_callback(topic, msg):
  m = msg.decode("utf-8")
  print("Current topic is %s, Value is %s"%(topic,m))

# Ket noi den broker
client_id = "AikdEQ4vAQsDECweNBA3KwA"
user_name = "AikdEQ4vAQsDECweNBA3KwA"
password = "QTD5rL/gbYq1ciW+5lJP66AV"
server = "mqtt3.thingspeak.com"
client = MQTTClient(client_id = client_id, server =server, user=user_name, password=password)
client.set_callback(handle_callback)
client.connect()
client.subscribe(b"channels/1556490/subscribe/fields/+")
publish_topic = b"channels/1556490/publish"

# Task 1: Publish data to MQTT broker each 5s 
async def task1():
  while True:
    print("Update temperature and humidity!")
    dht22.measure()
    t = dht22.temperature()
    h = dht22.humidity()
    payload = f"field1={t}&field2={h}&status=MQTTPUBLISH"
    client.publish(publish_topic,payload.encode("utf-8"))
    await asyncio.sleep_ms(5000)

# Task 2: 0.5s check if any data is sent from MQTT Broker?
async def task2():
  while True:
      client.check_msg()
      await asyncio.sleep_ms(500)


if __name__ == "__main__":
  loop = asyncio.get_event_loop()
  loop.create_task(task1())
  loop.create_task(task2())
  loop.run_forever()