import machine
import time
import network
from umqtt.simple import MQTTClient
import ssd1306  # OLED 驱动（Wokwi 需提前上传）
from machine import SoftI2C


# Wokwi 仿真环境配置
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD = ""
BROKER = "bemfa.com"
PORT = 9504
CLIENT_ID = "4c0da3b2d430b9f491fa15eabeb3ea21"  # 替换为你的巴法云 Client ID
TOPIC_LED = "led"
LED_PIN = 22

# OLED 初始化
OLED_WIDTH = 128
OLED_HEIGHT = 64
OLED_SDA = 26
OLED_SCL = 27
i2c = SoftI2C(sda=machine.Pin(OLED_SDA), scl=machine.Pin(OLED_SCL))
oled = ssd1306.SSD1306_I2C(OLED_WIDTH, OLED_HEIGHT, i2c, addr=0x3C)

# 全局变量
led = machine.Pin(LED_PIN, machine.Pin.OUT)
current_state = "off"
client = None  # MQTT 客户端

def display_info(line1, line2="", line3=""):
    """OLED 显示函数（最多3行）"""
    oled.fill(0)
    oled.text(line1, 0, 0)
    oled.text(line2, 0, 16)
    oled.text(line3, 0, 32)
    oled.show()

def connect_wifi():
    """连接 Wokwi 仿真 WiFi"""
    display_info("Connecting WiFi", WIFI_SSID)
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    if not wlan.isconnected():
        wlan.connect(WIFI_SSID, WIFI_PASSWORD)
        while not wlan.isconnected():
            time.sleep(0.5)
            display_info("Connecting...", WIFI_SSID)
    display_info("WiFi OK", f"IP: {wlan.ifconfig()[0]}")
    print("WiFi 已连接")

def mqtt_callback(topic, msg):
    """MQTT 消息回调（处理网页端指令）"""
    global current_state
    msg_str = msg.decode()
    print(f"收到指令: {msg_str}")
    
    if msg_str == "on":
        led.on()
        current_state = "on"
    elif msg_str == "off":
        led.off()
        current_state = "off"
    
    # 更新 OLED 和 MQTT 状态
    display_info("LED: " + current_state, "Topic: " + TOPIC)
    client.publish(TOPIC, current_state)  # 回传状态给网页

def connect_mqtt():
    """连接巴法云 MQTT 服务器"""
    global client
    try:
        client = MQTTClient(CLIENT_ID, BROKER, PORT)
        client.set_callback(mqtt_callback)
        client.connect()
        client.subscribe(TOPIC)  # 订阅主题，接收网页指令
        display_info("MQTT OK", BROKER, TOPIC)
        print("MQTT 已连接")
        return True
    except Exception as e:
        display_info("MQTT Err", str(e)[:16])
        print("MQTT 连接失败:", e)
        return False

def main():
    connect_wifi()
    if not connect_mqtt():
        return
    
    # 初始状态
    led.off()
    display_info("LED: off", "Topic: " + TOPIC)
    client.publish(TOPIC, "off")  # 上报初始状态
    
    # 主循环（保持 MQTT 在线）
    while True:
        try:
            client.check_msg()  # 检查 MQTT 消息
            time.sleep(0.1)
        except Exception as e:
            display_info("MQTT Err", str(e)[:16])
            print("MQTT 异常:", e)
            time.sleep(1)
            connect_mqtt()  # 尝试重连

if __name__ == "__main__":
    main()