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

# ===================== 你提供的巴法云信息 =====================
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD = ""
BAFA_CLIENT_ID = "8ed6f605289c4a809341ff69cf0d430f"  # 你的UID
BAFA_TOPIC = "light002"  # 你的主题
MQTT_BROKER = "bemfa.com"
MQTT_PORT = 9501
# =============================================================

# 初始化硬件
uart = UART(1, baudrate=115200, tx=1, rx=3)
led = Pin(2, Pin.OUT)  # LED 接 GPIO2
led_status = "off"

# MQTT 客户端
mqtt_client = None

# 连接 WiFi
def connect_wifi():
    uart.write(b"\rConnecting to WiFi...\n")
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    if not wlan.isconnected():
        wlan.connect(WIFI_SSID, WIFI_PASSWORD)
        max_wait = 20
        while max_wait > 0:
            if wlan.isconnected():
                break
            max_wait -= 1
            time.sleep(1)
            uart.write(b".")
    if wlan.isconnected():
        uart.write(b"\rWiFi connected! IP: " + wlan.ifconfig()[0].encode() + b"\n")
        return True
    else:
        uart.write(b"\rWiFi failed!\n")
        return False

# 连接 MQTT
def connect_mqtt():
    global mqtt_client
    uart.write(b"\rConnecting to MQTT...\n")
    mqtt_client = MQTTClient(
        client_id=BAFA_CLIENT_ID,
        server=MQTT_BROKER,
        port=MQTT_PORT,
        keepalive=60
    )
    try:
        mqtt_client.connect()
        uart.write(b"\rMQTT connected!\n")
        return True
    except Exception as e:
        uart.write(b"\rMQTT connect failed!\n")
        return False

# 接收巴法云指令（核心回调）
def on_mqtt_message(topic, msg):
    global led_status
    uart.write(b"\rReceived: " + msg + b"\n")

    # 巴法云下发 on → 亮
    if msg == b"on" or msg == b"ON":
        led.value(1)
        led_status = "on"
        uart.write(b"LED ON\n")

    # 巴法云下发 off → 灭
    elif msg == b"off" or msg == b"OFF":
        led.value(0)
        led_status = "off"
        uart.write(b"LED OFF\n")

# 发送状态到巴法云
def send_led_status(status):
    mqtt_client.publish(BAFA_TOPIC, status)
    uart.write(b"\rSent to Bemfa: " + status.encode() + b"\n")

# 主程序
def main():
    global led_status

    # 通电就亮灯
    led.value(1)
    led_status = "on"
    uart.write(b"\rLED ON AT START\n")

    # 连WiFi
    if not connect_wifi():
        return

    # 连MQTT
    if not connect_mqtt():
        return

    # 订阅主题 + 设置回调
    mqtt_client.set_callback(on_mqtt_message)
    mqtt_client.subscribe(BAFA_TOPIC)
    uart.write(b"\rSubscribed: " + BAFA_TOPIC.encode() + b"\n")

    # 上电发送 on 到巴法云
    send_led_status("on")

    # 循环
    while True:
        if mqtt_client:
            mqtt_client.check_msg()
        time.sleep(0.1)

if __name__ == "__main__":
    main()