import network
import time
from machine import Pin, I2C
import dht
import ujson
from umqtt.simple import MQTTClient
from i2c_lcd import I2cLcd

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

sensor = dht.DHT22(Pin(14))
led = Pin(13, Pin.OUT)

i2c = I2C(0, scl=Pin(22), sda=Pin(21), freq=400000)  

lcd = I2cLcd(i2c, 0x27, 2, 16)  

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.connect()

print("Connected!")

prev_weather = ""
while True:
    print("Measuring weather conditions... ", end="")
    sensor.measure()
    message = ujson.dumps({
        "temp": sensor.temperature(),
        "humidity": 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
        led.on()  

        lcd.clear()
        lcd.putstr("Temp: {} C\n".format(sensor.temperature()))
        lcd.putstr("Humidity: {}%".format(sensor.humidity()))

    else:
        print("No change")
        led.off()  

    time.sleep(1)


# https://www.hivemq.com/demos/websocket-client/