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

#Parametrizar el servidor MQTT.
MQTT_CLIENT_ID = "micropython-weather-demo_cordero"
MQTT_BROKER = "10.201.144.39"
#MQTT_BROKER = "broker.hivemq.com"
MQTT_PORT = 8883                    #Puerto por defecto sin SSL
MQTT_USER = ""
MQTT_PASSWORD = ""

#Configuración del sensor DHT22.
sensor = dht.DHT22(Pin(19))

# Configurar el pin GPIO 2 como salida
led = Pin(32, Pin.OUT)

# Tópicos MQTT
MQTT_TOPIC_SUB = "variables/rele"
MQTT_TOPIC_PUB = "variables/temphum"

# Conectar a la red Wi-Fi
def connect_wifi():
    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!")

# Función de callback para cuando recibimos un mensaje
def mqtt_callback(topic, msg):
    #Cuando recibo datos por MQTT los recibo como bytes b'Hola'
    topic_str = topic.decode('utf-8')
    msg_str = msg.decode('utf-8')
    print(f'Recibido mensaje en {topic_str}: {msg_str}')
    if msg_str == 'on':
        # Encender el LED
        led.on()
    if msg_str == 'off':
        # Apagar el LED
        led.off()

# Configuración y conexión al broker MQTT
def connect_mqtt():
    client = MQTTClient(MQTT_CLIENT_ID, MQTT_BROKER, port=MQTT_PORT, user=MQTT_USER, password=MQTT_PASSWORD)
    client.set_callback(mqtt_callback)
    client.connect()
    print('Conectado al broker MQTT')
    return client

# Publicar un mensaje
def publish_message(client, message):
    client.publish(MQTT_TOPIC_PUB, message)

# Suscribirse a un tema
def subscribe_topic(client):
    client.subscribe(MQTT_TOPIC_SUB)
    print(f'Suscrito al tema {MQTT_TOPIC_SUB}')

#Bucle Principal.
prev_weather = ""
try:
    connect_wifi()
    client = connect_mqtt()
    subscribe_topic(client)
    while True:
        client.check_msg()      # Verifica si hay mensajes sin bloquear el loop

        sensor.measure()
        message = ujson.dumps({
            "temperatura": sensor.temperature(),
            "humedad": sensor.humidity(),
        })
        if message != prev_weather:             #Solo publica cuando el dato a cambiado
            publish_message(client, message)
            print(message)
            prev_weather = message
        time.sleep(1)

except OSError as e:
    print('Error de conexión', e)