from machine import Pin
from umqtt.simple import MQTTClient
import ujson
import network
import utime as time
import dht


# Device Setup
DEVICE_ID = "wokwi001"

# WiFi Setup
WIFI_SSID       = "Wokwi-GUEST"
WIFI_PASSWORD   = ""

# MQTT Setup
MQTT_BROKER             = "mqtt-dashboard.com"
MQTT_CLIENT             = DEVICE_ID
MQTT_TELEMETRY_TOPIC    = "iot/telemetry"

# DHT Sensor Setup
DHT_PIN = Pin(15)

# Methods
def did_recieve_callback(topic, message):
    print('\n\nData Recieved! \ntopic = {0}, message = {1}'.format(topic, message))  

def mqtt_connect():
    print("Connecting to MQTT broker ...", end="")
    mqtt_client = MQTTClient(MQTT_CLIENT, MQTT_BROKER, user="", password="")
    mqtt_client.set_callback(did_recieve_callback)
    mqtt_client.connect()
    print("Connected.")
    return mqtt_client

def create_json_data(temperature):
    data = ujson.dumps({
        "temp": temperature,
    })
    return data

def mqtt_client_publish(topic, data):
    print("\nUpdating MQTT Broker...")
    mqtt_client.publish(topic, data)
    print(data)


# Application Logic

# Connect to WiFi
wifi_client = network.WLAN(network.STA_IF)
wifi_client.active(True)
print("Connecting device to WiFi")
wifi_client.connect(WIFI_SSID, WIFI_PASSWORD)

# Wait until WiFi is Connected
while not wifi_client.isconnected():
    print("Connecting")
    time.sleep(0.1)
print("WiFi Connected!")
print(wifi_client.ifconfig())

# Connect to MQTT
mqtt_client = mqtt_connect()
dht_sensor = dht.DHT22(DHT_PIN)
telemetry_data_old = ""

while True:
    mqtt_client.check_msg()
    print(". ", end="")
    try:
      dht_sensor.measure()
    except:
      pass
    time.sleep(0.2)
    telemetry_data_new = create_json_data(dht_sensor.temperature())

    if telemetry_data_new != telemetry_data_old:
        mqtt_client_publish(MQTT_TELEMETRY_TOPIC, telemetry_data_new)
        telemetry_data_old = telemetry_data_new

    time.sleep(0.1)