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(20, Pin.IN))

def handle_callback (topic, msg):
    m = msg.decode("utf 8")
    print(m)

#Ket noi den broker
client_id   = "GjcbOCszCystNhAsHiQCJhg"
user_name   = "GjcbOCszCystNhAsHiQCJhg"
password    = "vuzm8dONqSSCniK4O1iJNIo0"
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/2501169/subscribe/fields/+")
publish_topic = b"channels/2501169/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()