import dht
import machine
import time
from machine import Pin, I2C
import ssd1306
import network
from umqtt.simple import MQTTClient

# 全局配置
DHT_PIN = 14  # DHT22数据引脚连接到GPIO14

# SSD1306 OLED配置
OLED_WIDTH = 128
OLED_HEIGHT = 64
OLED_SDA = 4  # GPIO4
OLED_SCL = 5  # GPIO5

# Wokwi WiFi配置
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD = ""

# 巴法云MQTT配置
MQTT_CLIENT_ID = "f8d91192b8cf47b79d6cf0bc28cba822" 
MQTT_BROKER = "bemfa.com" 
MQTT_PORT = 9501
MQTT_USER = "[email protected]" 
MQTT_PASSWORD = "956351911" 
TOPIC_TEMP = "temp" 
TOPIC_HUM = "hum" 

# 初始化I2C和OLED
i2c = I2C(0, sda=Pin(OLED_SDA), scl=Pin(OLED_SCL), freq=400000)
oled = ssd1306.SSD1306_I2C(OLED_WIDTH, OLED_HEIGHT, i2c)

# 初始化WiFi
wifi = network.WLAN(network.STA_IF)
wifi.active(True)

def connect_wifi():
    """连接WiFi网络"""
    if not wifi.isconnected():
        print("正在连接WiFi...")
        oled.fill(0)
        oled.text("Connecting WiFi", 0, 20)
        oled.show()
        
        wifi.connect(WIFI_SSID, WIFI_PASSWORD)
        max_attempts = 20  # 增加尝试次数
        while not wifi.isconnected() and max_attempts > 0:
            max_attempts -= 1
            print(f"等待WiFi连接...剩余尝试 {max_attempts}次")
            time.sleep(1)
    
    if wifi.isconnected():
        print("WiFi连接成功:", wifi.ifconfig())
        oled.fill(0)
        oled.text("WiFi Connected", 0, 20)
        oled.text(wifi.ifconfig()[0], 0, 35)
        oled.show()
        time.sleep(1)
    else:
        print("WiFi连接失败")
        oled.fill(0)
        oled.text("WiFi Failed", 0, 20)
        oled.show()
        raise RuntimeError("无法连接WiFi")

# 初始化MQTT客户端
mqtt_client = MQTTClient(
    client_id=MQTT_CLIENT_ID,
    server=MQTT_BROKER,
    port=MQTT_PORT,
    user=MQTT_USER,
    password=MQTT_PASSWORD,
    keepalive=30  # 缩短心跳间隔
)

def mqtt_callback(topic, msg):
    """MQTT消息回调函数"""
    print(f"收到消息: {topic.decode()} -> {msg.decode()}")
    # 可以在OLED上显示收到的消息
    oled.fill(0)
    oled.text("MQTT Msg:", 0, 0)
    oled.text(f"{topic.decode()}:{msg.decode()}", 0, 20)
    oled.show()
    time.sleep(2)

def connect_mqtt():
    """连接MQTT服务器并订阅主题"""
    try:
        mqtt_client.set_callback(mqtt_callback)
        mqtt_client.connect()
        print("MQTT连接成功")
        
        # 订阅主题（使状态显示为在线）
        mqtt_client.subscribe(TOPIC_TEMP)
        mqtt_client.subscribe(TOPIC_HUM)
        print(f"已订阅主题: {TOPIC_TEMP}, {TOPIC_HUM}")
        
        oled.fill(0)
        oled.text("MQTT Connected", 0, 20)
        oled.text("Subscribed!", 0, 35)
        oled.show()
        time.sleep(1)
    except Exception as e:
        print(f"MQTT连接失败: {e}")
        oled.fill(0)
        oled.text("MQTT Failed", 0, 20)
        oled.text(str(e)[:20], 0, 35)  # 显示部分错误信息
        oled.show()
        raise

def read_sensor_data():
    """读取DHT22传感器数据"""
    sensor = dht.DHT22(machine.Pin(DHT_PIN))
    try:
        sensor.measure()
        temperature = sensor.temperature()
        humidity = sensor.humidity()
        return temperature, humidity
    except OSError as e:
        print(f"传感器读取错误: {e}")
        return None, None

def publish_data(temperature, humidity):
    """通过MQTT发布数据到巴法云"""
    try:
        if temperature is not None:
            mqtt_client.publish(TOPIC_TEMP, str(temperature))
            print(f"已发布温度: {temperature}°C")
        if humidity is not None:
            mqtt_client.publish(TOPIC_HUM, str(humidity))
            print(f"已发布湿度: {humidity}%")
    except Exception as e:
        print(f"MQTT发布失败: {e}")
        # 尝试重新连接
        connect_mqtt()

def display_data(temperature, humidity):
    """在OLED和串口上显示数据"""
    oled.fill(0)
    oled.text("Env Monitor", 0, 0)
    for x in range(OLED_WIDTH):
        oled.pixel(x, 12, 1)
    
    if temperature is not None and humidity is not None:
        oled.text(f"Temp: {temperature:.1f}C", 0, 20)
        oled.text(f"Hum:  {humidity:.1f}%", 0, 35)
        
        if temperature > 30:
            oled.text("HOT!", 80, 20)
        elif temperature < 15:
            oled.text("COLD!", 80, 20)
            
        if humidity > 70:
            oled.text("HUMID!", 80, 35)
            
        print(f"温度: {temperature}°C | 湿度: {humidity}%")
        publish_data(temperature, humidity)
    else:
        oled.text("Sensor Error!", 0, 20)
        print("无法获取传感器数据")
    
    # 显示连接状态
    status = f"WiFi:{'On' if wifi.isconnected() else 'Off'}"
    status += f" MQTT:{'On' if mqtt_client.sock else 'Off'}"
    oled.text(status, 0, 50)
    oled.show()

def main():
    """主函数，程序入口点"""
    print("DHT22温度监控系统启动...")
    
    # 初始连接
    connect_wifi()
    connect_mqtt()
    
    try:
        while True:
            # 检查MQTT消息
            try:
                mqtt_client.check_msg()  # 检查新消息
            except Exception as e:
                print(f"检查消息错误: {e}")
                connect_mqtt()  # 出错时重新连接
            
            # 读取和显示数据
            temperature, humidity = read_sensor_data()
            display_data(temperature, humidity)
            
            # 保持连接
            try:
                mqtt_client.ping()
            except:
                connect_mqtt()
                
            time.sleep(2)
            
    except KeyboardInterrupt:
        print("\n程序已停止")
        mqtt_client.disconnect()
    except Exception as e:
        print(f"发生错误：{e}")
        mqtt_client.disconnect()

if __name__ == "__main__":
    main()