import network
import time
from machine import Pin, I2C
import dht
import ujson
from umqtt.simple import MQTTClient
import ssd1306

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

# OLED Parameters
OLED_WIDTH = 128
OLED_HEIGHT = 64
i2c = I2C(0, scl=Pin(22), sda=Pin(21))
oled = ssd1306.SSD1306_I2C(OLED_WIDTH, OLED_HEIGHT, i2c)

sensor = 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="")
        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
                                          
                                              # Display data on OLED
                                                  oled.fill(0)
                                                      oled.text("Temp: {} C".format(sensor.temperature()), 0, 0)
                                                          oled.text("Humidity: {}%".format(sensor.humidity()), 0, 20)
                                                              oled.show()
                                                                else:
                                                                    print("No change")
                                                                      time.sleep(1)