from machine import Pin
import time

# Define pin numbers
PIN_TRIG = 26
PIN_ECHO = 25
LOW_LED = 18
MID_LED = 19
HIGH_LED = 21
MOTOR = 27

# Setup pins
trig = Pin(PIN_TRIG, Pin.OUT)
echo = Pin(PIN_ECHO, Pin.IN)
low_led = Pin(LOW_LED, Pin.OUT)
mid_led = Pin(MID_LED, Pin.OUT)
high_led = Pin(HIGH_LED, Pin.OUT)
motor = Pin(MOTOR, Pin.OUT)

# Initialize pin states
low_led.value(1)   # LED OFF (Active LOW)
mid_led.value(1)   # LED OFF
high_led.value(1)  # LED OFF
motor.value(0)     # Motor OFF (Active HIGH)

def measure_distance():
    # Send a 10-microsecond pulse to trigger pin
    trig.value(1)
    time.sleep_us(10)
    trig.value(0)

    # Measure the pulse duration on the echo pin
    while echo.value() == 0:
        pass
    start_time = time.ticks_us()

    while echo.value() == 1:
        pass
    end_time = time.ticks_us()

    # Calculate distance (duration in microseconds -> distance in cm)
    duration = time.ticks_diff(end_time, start_time)
    distance_cm = duration / 58
    return distance_cm

while True:
    distance = measure_distance()
    print("Distance in CM:", distance)
    print("Distance in inches:", distance / 2.54)

    # Control LEDs and motor based on distance
    if distance < 100:  # Low water level
        low_led.value(0)  # Turn ON LOW_LED
        mid_led.value(1)  # Turn OFF MID_LED
        high_led.value(1) # Turn OFF HIGH_LED
        motor.value(1)    # Turn ON MOTOR

    elif 100 <= distance < 400:  # Medium water level
        low_led.value(1)  # Turn OFF LOW_LED
        mid_led.value(0)  # Turn ON MID_LED
        high_led.value(1) # Turn OFF HIGH_LED
        
    elif distance >= 400:  # High water level
        low_led.value(1)  # Turn OFF LOW_LED
        mid_led.value(1)  # Turn OFF MID_LED
        high_led.value(0) # Turn ON HIGH_LED
        motor.value(0)    # Turn OFF MOTOR

    time.sleep(1)  # Wait 1 second before next measurement