import dht
import machine
import time
import ssd1306  

# 全局配置
DHT_PIN = 14        # DHT22数据引脚
I2C_SCL = 5         # OLED I2C 时钟线
I2C_SDA = 4         # OLED I2C 数据线
OLED_WIDTH = 128    # OLED 宽度
OLED_HEIGHT = 64    # OLED 高度
MQ2_ADC_PIN = 0     # MQ2 模拟输出接 ADC0
MQ2_DIGITAL_PIN = 18# MQ2 数字输出接 GPIO18

# MQ2 简化配置（直接用原始 ADC 值，复杂校准可后续扩展）
SMOKE_THRESHOLD = 2000  # 烟雾触发阈值（根据实际校准调整）

def init_display():
    """初始化 OLED 显示屏"""
    i2c = machine.I2C(scl=machine.Pin(I2C_SCL), sda=machine.Pin(I2C_SDA))
    return ssd1306.SSD1306_I2C(OLED_WIDTH, OLED_HEIGHT, i2c)

def init_mq2():
    """初始化 MQ2 传感器（ADC + 数字引脚）"""
    adc = machine.ADC(MQ2_ADC_PIN)
    digital_pin = machine.Pin(MQ2_DIGITAL_PIN, machine.Pin.IN)
    return adc, digital_pin

def read_dht22():
    """读取 DHT22 温湿度（增加重试逻辑）"""
    dht_sensor = dht.DHT22(machine.Pin(DHT_PIN))
    for _ in range(3):
        try:
            dht_sensor.measure()
            return dht_sensor.temperature(), dht_sensor.humidity()
        except OSError:
            time.sleep(1)
    return None, None

def read_mq2(adc, digital_pin):
    """读取 MQ2 原始数据（简化版，对齐 Wokwi 逻辑）"""
    adc_value = adc.read()  # 直接读 ADC 原始值
    digital_state = digital_pin.value()
    is_smoke = digital_state == 0 or adc_value > SMOKE_THRESHOLD
    return adc_value, is_smoke

def display_data(temperature, humidity, mq2_adc, is_smoke, display):
    """显示所有数据到 OLED 和终端"""
    display.fill(0)
    
    # 显示 DHT22 数据
    if temperature is not None and humidity is not None:
        print(f"温度: {temperature}°C | 湿度: {humidity}%")
        display.text(f"Temp: {temperature} C", 0, 0)
        display.text(f"Humi: {humidity} %", 0, 12)
    else:
        print("DHT22 读取失败")
        display.text("DHT22 Error", 0, 0)
    
    # 显示 MQ2 数据
    print(f"MQ2 原始值: {mq2_adc} | 烟雾检测: {'是' if is_smoke else '否'}")
    display.text(f"MQ2: {mq2_adc}", 0, 24)
    display.text(f"Smoke: {'Detected' if is_smoke else 'Normal'}", 0, 36)
    
    display.show()

def main():
    """主程序逻辑"""
    print("监控系统启动...")
    display = init_display()
    display.text("Starting...", 0, 0)
    display.show()
    
    adc, digital_pin = init_mq2()
    time.sleep(2)
    
    try:
        while True:
            # 读取传感器
            temp, humi = read_dht22()
            mq2_adc, is_smoke = read_mq2(adc, digital_pin)
            
            # 显示数据
            display_data(temp, humi, mq2_adc, is_smoke, display)
            
            time.sleep(1)
    except KeyboardInterrupt:
        print("\n程序停止")
        display.fill(0)
        display.text("Stopped", 0, 0)
        display.show()
    except Exception as e:
        print(f"错误: {e}")
        display.fill(0)
        display.text("Error", 0, 0)
        display.show()

if __name__ == "__main__":
    main()