import network
import machine
import time
from umqtt.simple import MQTTClient

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

THINGSBOARD_HOST = "demo.thingsboard.io"
THINGSBOARD_TOKEN = "votre_TOKEN"
MQTT_CLIENT_ID = "esp32_ultrasonic"

TRIG_PIN = 14
ECHO_PIN = 12

# ---------------- CONNEXION WI-FI ----------------
def connect_wifi():
    wifi = network.WLAN(network.STA_IF)
    wifi.active(True)
    wifi.connect(WIFI_SSID, WIFI_PASSWORD)

    print("Connexion au Wi-Fi en cours...")
    while not wifi.isconnected():
        time.sleep(1)

    print("Wi-Fi connecté :", wifi.ifconfig())

connect_wifi()

# ---------------- CAPTEUR ULTRASONIQUE ----------------
trig = machine.Pin(TRIG_PIN, machine.Pin.OUT)
echo = machine.Pin(ECHO_PIN, machine.Pin.IN)

def get_distance():
    trig.value(0)
    time.sleep_us(2)
    trig.value(1)
    time.sleep_us(10)
    trig.value(0)

    pulse_time = machine.time_pulse_us(echo, 1, 30000)  # Timeout de 30ms
    if pulse_time < 0:
        return None  # Aucun signal reçu

    distance = (pulse_time * 0.0343) / 2
    return round(distance, 2)

# ---------------- CONNEXION MQTT ----------------
def connect_mqtt():
    try:
        client = MQTTClient(MQTT_CLIENT_ID, THINGSBOARD_HOST, user=THINGSBOARD_TOKEN, password="", port=1883)
        client.connect()
        print("Connecté à ThingsBoard MQTT")
        return client
    except Exception as e:
        print("Erreur MQTT :", e)
        return None

client = connect_mqtt()

# ---------------- BOUCLE PRINCIPALE ----------------
while client is not None:
    distance = get_distance()
    
    if distance is not None:
        print("Distance mesurée :", distance, "cm")
        message = '{"distance": ' + str(distance) + '}'
        client.publish("v1/devices/me/telemetry", message)
    else:
        print("Erreur : mesure échouée")

    time.sleep(2)