import machine
import time

# Pins for sensor, relay, and buttons
TRIG_PIN = 15
ECHO_PIN = 13
RELAY_PIN = 12
ON_BUTTON_PIN = 14     # Pin for manual ON button
OFF_BUTTON_PIN = 27    # Pin for manual OFF button

# Setup the pins
trig = machine.Pin(TRIG_PIN, machine.Pin.OUT)
echo = machine.Pin(ECHO_PIN, machine.Pin.IN)
relay = machine.Pin(RELAY_PIN, machine.Pin.OUT)
on_button = machine.Pin(ON_BUTTON_PIN, machine.Pin.IN, machine.Pin.PULL_UP)   # Manual ON button
off_button = machine.Pin(OFF_BUTTON_PIN, machine.Pin.IN, machine.Pin.PULL_UP)  # Manual OFF button

# Initialize motor state
motor_on = False  # Assume motor starts on

# Function to measure distance
def get_distance():
    trig.off()
    time.sleep_us(2)
    trig.on()
    time.sleep_us(10)
    trig.off()
    
    # Initialize start_time and end_time properly
    start_time = 0
    end_time = 0
    
    # Wait for echo signal to go HIGH
    while echo.value() == 0:
        start_time = time.ticks_us()
    
    # Wait for echo signal to go LOW
    while echo.value() == 1:
        end_time = time.ticks_us()
    
    # Calculate distance based on the time difference
    elapsed_time = end_time - start_time
    distance = (elapsed_time * 0.0343) / 2  # Speed of sound is 343 m/s
    return distance

# Debouncing function to check if a button is pressed
def button_pressed(button):
    if button.value() == 0:  # Button is pressed (LOW)
        time.sleep(0.05)  # Wait 50ms for debounce
        if button.value() == 0:  # If still pressed after debounce
            return True
    return False

# Main loop to monitor water level and handle manual buttons
while True:
    distance = get_distance()
    print(f"Water level: {distance} cm")

    # Check if the water tank is full
    if distance < 10:  # Assuming 10 cm is the threshold for full tank
        if motor_on:  # Turn off motor only if it is currently on
            relay.off()  # Turn off the motor
            motor_on = False  # Update motor state
            print("Motor turned off. Tank is full.")
    
    # Manual ON button logic
    if not motor_on and button_pressed(on_button):  # If motor is off and ON button is pressed
        relay.on()  # Turn on the motor
        motor_on = True  # Update motor state
        print("Manual ON button pressed. Motor turned on.")
    
    # Manual OFF button logic
    if motor_on and button_pressed(off_button):  # If motor is on and OFF button is pressed
        relay.off()  # Turn off the motor
        motor_on = False  # Update motor state
        print("Manual OFF button pressed. Motor turned off.")

    time.sleep(0)