print("Hello, Pi Pico!")
from machine import Pin
import utime
import time

Pb_Switch = Pin(15, Pin.IN, Pin.PULL_DOWN)
trigger = Pin(3, Pin.OUT)
echo = Pin(2, Pin.IN)
relay = Pin(16, Pin.OUT)

def Pb_Switch_INT(pin):
    global Pb_Switch_State
    global warning_LED
    global interrupt_occurred
    Pb_Switch.irq(handler=None)
    if (Pb_Switch.value() == 1) and (Pb_Switch_State == 0):
        Pb_Switch_State = 1
        warning_LED.value(1)
        interrupt_occurred = True
        relay.value(0)
        print("Interrupt Enabled")
    elif (Pb_Switch.value() == 0) and (Pb_Switch_State == 1):
        Pb_Switch_State = 0
        warning_LED.value(0)
        interrupt_occurred = False
        print("Interrupt Disabled")
    Pb_Switch.irq(trigger=Pin.IRQ_RISING | Pin.IRQ_FALLING, handler=Pb_Switch_INT)

def ultra():
    trigger.low()
    utime.sleep_us(2)
    trigger.high()
    utime.sleep_us(5)
    trigger.low()
    while echo.value() == 0:
        signaloff = utime.ticks_us()
    while echo.value() == 1:
        signalon = utime.ticks_us()
    timepassed = signalon - signaloff
    distance = (timepassed * 0.0343) / 2
    print("The distance from the object is ", distance, "cm")
    if distance < 100:
        relay.value(1)
    else:
        relay.value(0)

Pb_Switch.irq(trigger=Pin.IRQ_RISING | Pin.IRQ_FALLING, handler=Pb_Switch_INT)
Pb_Switch_State = Pb_Switch.value()
warning_LED = Pin(28, Pin.OUT)
warning_LED.value(0)
interrupt_occurred = False

while True:
    if not interrupt_occurred:
        ultra()
        utime.sleep(1)