import network
import time
from machine import Pin, SoftI2C
import dht
import ujson
from umqtt.simple import MQTTClient
from i2c_lcd import I2cLcd


I2C_ADDR = 0x27
totalRows = 2
totalColumns = 16
i2c = SoftI2C(scl=Pin(22), sda=Pin(21), freq=400000)
lcd = I2cLcd(i2c, I2C_ADDR, totalRows, totalColumns)

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

d = dht.DHT22(Pin(15))

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="")
  d.measure() 
  t = d.temperature()
  h = d.humidity()
  message = ujson.dumps({
    "temp": t,
    "humidity": h,
  })
  if message != prev_weather:
    print("Updated!")
    lcd.move_to(0,0)
    lcd.putstr('Nhiet do:'+ str(t))
    lcd.move_to(0,1)
    lcd.putstr('Do am:' + str(h))
    print("Reporting to MQTT topic {}: {}".format(MQTT_TOPIC, message))
    client.publish(MQTT_TOPIC,message)
    prev_weather = message
  else:
    print("No change")
  time.sleep(1)