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

# Wi-Fi 配置
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD = ""

# MQTT 配置
MQTT_CLIENT_ID = "esp32-led-demo"
MQTT_BROKER = "broker.mqttdashboard.com"
MQTT_USER = ""
MQTT_PASSWORD = ""
MQTT_TOPIC = "esp32led"

# 配置 LED 引脚（15 号引脚）
led = Pin(15, Pin.OUT)
led.off()  # 初始状态：关闭

# MQTT 回调函数，处理接收到的消息
def on_message(topic, msg):
    print(f"Received message on topic {topic.decode()}: {msg.decode()}")
    if msg.decode().lower() == "on":
        led.on()
        print("LED turned ON")
    elif msg.decode().lower() == "off":
        led.off()
        print("LED turned OFF")

# 连接到 Wi-Fi
print("Connecting to WiFi", end="")
sta_if = network.WLAN(network.STA_IF)
sta_if.active(True)
sta_if.connect(WIFI_SSID, WIFI_PASSWORD)
while not sta_if.isconnected():
    print(".", end="")
    time.sleep(0.1)
print(" Connected!")

# 连接到 MQTT 经纪人
print("Connecting to MQTT server...", end="")
client = MQTTClient(MQTT_CLIENT_ID, MQTT_BROKER, user=MQTT_USER, password=MQTT_PASSWORD)
client.set_callback(on_message)
client.connect()
client.subscribe(MQTT_TOPIC)
print("Connected and subscribed to topic:", MQTT_TOPIC)

# 主循环：检查 MQTT 消息
while True:
    client.check_msg()
    time.sleep(0.1)