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

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

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 = ""


I2C_ADDR = 0x27
totalRows = 2
totalColumns = 16

i2c = SoftI2C(scl=Pin(22), sda=Pin(21), freq=10000)

LCD = I2cLcd(i2c, I2C_ADDR, totalRows, totalColumns)

DHT = dht.DHT22(Pin(4))

LEDT=Pin(32,Pin.OUT)   
LEDH=Pin(33,Pin.OUT)   

last_t=0
last_h=0
while True:
  try:
    sleep(2)
    DHT.measure()
    t = DHT.temperature()
    h = DHT.humidity()

    if t<18 or t>25:
      LEDT.value(1)
    else:
      LEDT.value(0)

    if h<20 or h>60:
      LEDH.value(1)
    else:
      LEDH.value(0)

    if t!=last_t or h!=last_h:
      LCD.clear()
      LCD.putstr("t: %3.1f C\n" %t)
      LCD.putstr("h: %3.1f %%" %h)
      last_t=t
      last_h=h
    print("Measuring weather conditions... ", end="")
  message = ujson.dumps({
    "temp": t,
    "humidity": h,
  })
  if message != prev_weather:
    print("Updated!")
    print("Reporting to MQTT topic {}: {}".format(MQTT_TOPIC, message))
    client.publish(MQTT_TOPIC, message)
    prev_weather = message
  else:
    print("No change")
    time.sleep(1)

  except OSError as e:
    print('Failed to read sensor.')