"""
MicroPython IoT Weather Station Example for Wokwi.com

To view the data:

1. Go to http://www.hivemq.com/demos/websocket-client/
2. Click "Connect"
3. Under Subscriptions, click "Add New Topic Subscription"
4. In the Topic field, type "wokwi-weather" then click "Subscribe"

Now click on the DHT22 sensor in the simulation,
change the temperature/humidity, and you should see
the message appear on the MQTT Broker, in the "Messages" pane.

Copyright (C) 2022, Uri Shaked

https://wokwi.com/arduino/projects/322577683855704658
"""

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 = "chennie2206054042"
MQTT_BROKER    = "broker.emqx.io"
MQTT_USER      = ""
MQTT_PASSWORD  = ""
MQTT_TOPIC     = "chennie2206054042"

sensor = dht.DHT22(Pin(15))

i2c=I2C(0,scl=Pin(22),sda=Pin(21))
oled_width=128
oled_height=64
oled=ssd1306.SSD1306_I2C(oled_width,oled_height,i2c)
oled.text('Hello,chennie223!',10,10)
oled.show()

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() 
  msg_data={
    "temp": sensor.temperature(),
    "humidity": sensor.humidity(),
  }
  message=ujson.dumps(msg_data)
  if message != prev_weather:
    print("Updated!")
    print("Reporting to MQTT topic {}: {}".format(MQTT_TOPIC, message))
    oled.text("%.1f dc"%(msg_data["temp"]),10,20)
    oled.text("%.1f %%"%(msg_data["humidity"]),10,30)
    oled.show()
    client.publish(MQTT_TOPIC, message)
    prev_weather = message
  else:
    print("No change")
  time.sleep(1)