import time
from machine import Pin, time_pulse_us

# ---------------------- 全局参数配置 ----------------------
MIN_DISTANCE = 10    # 传感器有效最小距离（cm）
MAX_DISTANCE = 50    # 传感器有效最大距离（cm）
ULTRASONIC_TIMEOUT = 15000  # 超声波超时时间（us）
CHECK_INTERVAL = 1   # 检测间隔（s）

# ---------------------- 水位检测系统类 ----------------------
class WaterLevelSystem:
    def __init__(self):
        # LED配置（红、黄、绿）
        self.leds = {
            'red': Pin(21, Pin.OUT, value=0),    # 红灯→GPIO21
            'yellow': Pin(22, Pin.OUT, value=0), # 黄灯→GPIO22
            'green': Pin(23, Pin.OUT, value=0)   # 绿灯→GPIO23
        }

        # 超声波传感器配置（Trig=输出，Echo=输入）
        self.sensors = [
            {'trig': Pin(13, Pin.OUT), 'echo': Pin(12, Pin.IN), 'pos': 1},  # 1号传感器
            {'trig': Pin(14, Pin.OUT), 'echo': Pin(27, Pin.IN), 'pos': 2},  # 2号传感器
            {'trig': Pin(26, Pin.OUT), 'echo': Pin(25, Pin.IN), 'pos': 3},  # 3号传感器
            {'trig': Pin(33, Pin.OUT), 'echo': Pin(32, Pin.IN), 'pos': 4}   # 4号传感器
        ]

    # 测量单个传感器距离
    def _get_sensor_distance(self, sensor):
        trig = sensor['trig']
        echo = sensor['echo']
        
        trig.off()
        time.sleep_us(2)
        trig.on()
        time.sleep_us(10)
        trig.off()
        
        pulse_duration = time_pulse_us(echo, 1, ULTRASONIC_TIMEOUT)
        if pulse_duration <= 0:
            print(f"Sensor {sensor['pos']}: Timeout")
            return 0
        distance = (pulse_duration * 0.0343) / 2  # 计算距离
        return round(distance, 1)

    # 获取活跃传感器（检测到水位的）
    def get_active_sensors(self):
        active = []
        for sensor in self.sensors:
            dist = self._get_sensor_distance(sensor)
            print(f"Sensor {sensor['pos']}: {dist}cm")
            if MIN_DISTANCE <= dist <= MAX_DISTANCE:
                active.append(sensor['pos'])
        return active

    # 判定水位状态并控制LED
    def run_monitor(self):
        active_sensors = self.get_active_sensors()
        print(f"Active Sensors: {active_sensors}\n")
        
        # 先关闭所有LED
        for led in self.leds.values():
            led.off()
        
        # 根据状态开对应LED
        if not active_sensors:
            self.leds['red'].on()  # 危险（无水位）
            print("Status: Danger (No Water)\n")
        elif active_sensors == [1]:
            self.leds['yellow'].on()  # 警告（低水位）
            print("Status: Warning (Low Water)\n")
        elif active_sensors == [1, 2]:
            self.leds['green'].on()  # 安全（正常水位）
            print("Status: Safe (Normal Water)\n")
        elif active_sensors == [1, 2, 3]:
            self.leds['yellow'].on()  # 警告（高水位）
            print("Status: Warning (High Water)\n")
        elif active_sensors == [1, 2, 3, 4]:
            self.leds['red'].on()  # 危险（满水位）
            print("Status: Danger (Full Water)\n")
        else:
            print("Status: Error (Unknown Sensor State)\n")

# ---------------------- 主程序 ----------------------
if __name__ == "__main__":
    water_system = WaterLevelSystem()
    print("Start Water Level Monitoring...\n")
    try:
        while True:
            water_system.run_monitor()
            time.sleep(CHECK_INTERVAL)
    except KeyboardInterrupt:
        print("Monitoring Stopped")
        # 关闭所有LED
        for led in water_system.leds.values():
            led.off()