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

# --- Configuration ---
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD = ""

MQTT_CLIENT_ID = "micropython-weather-data"
MQTT_BROKER = "sensor-micro.cloud.shiftr.io"
MQTT_USER = "sensor-micro"
MQTT_PASSWORD = "ulcB4x2V9ghmWzTo"
MQTT_TOPIC = "wokwi-weather"

DHT_PIN = 15
MEASURE_INTERVAL = 1  # seconds

# --- Initialize Sensor ---
sensor = dht.DHT22(Pin(DHT_PIN))

# --- Connect to WiFi ---
def connect_wifi():
    print("Connecting to WiFi", end="")
    sta = network.WLAN(network.STA_IF)
    sta.active(True)
    sta.connect(WIFI_SSID, WIFI_PASSWORD)

    while not sta.isconnected():
        print(".", end="")
        time.sleep(0.1)
    print(" Connected!")

# --- Connect to MQTT ---
def connect_mqtt():
    print("Connecting to MQTT server... ", end="")
    client = MQTTClient(
        client_id=MQTT_CLIENT_ID,
        server=MQTT_BROKER,
        user=MQTT_USER,
        password=MQTT_PASSWORD
    )
    client.connect()
    print("Connected!")
    return client

# --- Main Loop ---
def main():
    connect_wifi()
    client = connect_mqtt()

    prev_message = ""

    while True:
        print("Measuring weather conditions... ", end="")
        sensor.measure()

        message = ujson.dumps({
            "temperature": sensor.temperature(),
            "humidity": sensor.humidity()
        })

        if message != prev_message:
            print("Updated!")
            print(f"Reporting to MQTT topic {MQTT_TOPIC}: {message}")
            client.publish(MQTT_TOPIC, message)
            prev_message = message
        else:
            print("No change")

        time.sleep(MEASURE_INTERVAL)

# --- Run Program ---
if __name__ == "__main__":
    main()