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

# WiFi 配置
WIFI_SSID = "Wokwi-GUEST"       # 替换为实际 WiFi 名
WIFI_PASSWORD = ""   # 替换为实际 WiFi 密码

# 巴法云配置
BAFAYUN_SERVER = "bemfa.com"
BAFAYUN_PORT = 9501
BAFAYUN_CLIENT_ID = "8714483521c64509be3a0e818367c9fa"  # 替换为你的巴法云私钥
BAFAYUN_TOPIC = "sensor"            # 主题名称，注意拼写

# GPIO 定义（控制继电器/LED）
ALARM_PIN = Pin(15, Pin.OUT)  # ESP32 引脚 15，输出模式
ALARM_THRESHOLD = 300         # 烟雾浓度阈值，低于此值触发报警

# 连接 WiFi
def connect_wifi():
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    if not wlan.isconnected():
        print('连接到 WiFi...')
        wlan.connect(WIFI_SSID, WIFI_PASSWORD)
        while not wlan.isconnected():
            time.sleep(1)
    print('WiFi 连接成功，网络配置:', wlan.ifconfig())

# 读取 MQ2 传感器数据（模拟）
def read_mq2():
    # 实际项目中替换为真实传感器读取逻辑，例如：return mq2_sensor.read()
    return random.uniform(0, 1000)  # 模拟数据 0-1000

# 订阅消息回调函数
def sub_callback(topic, msg):
    print(f"收到主题 {topic.decode()} 的消息: {msg.decode()}")
    # 可扩展：根据收到的消息执行手动模式/自动模式切换等逻辑

# 主函数
def main():
    connect_wifi()
    
    # 连接巴法云 MQTT 服务器
    client = MQTTClient(BAFAYUN_CLIENT_ID, BAFAYUN_SERVER, BAFAYUN_PORT)
    client.set_callback(sub_callback)
    
    try:
        client.connect()
        print("成功连接到巴法云 MQTT 服务器")
        client.subscribe(BAFAYUN_TOPIC)
        print(f"已订阅主题: {BAFAYUN_TOPIC}")
        
        while True:
            # 1. 读取传感器数据
            mq2_value = read_mq2()
            print(f"当前 MQ2 浓度: {mq2_value:.2f}")
            
            # 2. 发布数据到巴法云
            client.publish(BAFAYUN_TOPIC, str(mq2_value))
            print(f"已发布数据: {mq2_value:.2f}")
            
            # 3. 报警逻辑：浓度低于阈值时，控制 LED 闪烁
            if mq2_value < ALARM_THRESHOLD:
                ALARM_PIN.value(1)
                time.sleep(0.5)
                ALARM_PIN.value(0)
                time.sleep(0.5)
                print("触发报警：烟雾浓度低于阈值！")
            else:
                ALARM_PIN.value(0)
            
            # 4. 检查订阅消息
            client.check_msg()
            time.sleep(5)  # 每 5 秒执行一次
            
    except Exception as e:
        print(f"连接错误: {e}")
    finally:
        client.disconnect()

if __name__ == "__main__":
    main()