print("Hello, ESP32!")

#####################################
###### IMPORT LIBRARIES
from machine import Pin
from time import sleep

#####################################
###### PIN CONFIGURATIONS
# Configure the LED and LDR (via digital pin)
pin_led = Pin(21, Pin.OUT)
pin_ldr = Pin(33, Pin.IN)  # Digital input from LDR comparator (HIGH when > 100 lux)

#####################################
###### SUBROUTINE FOR INTERRUPT #####
def interrupt_ldr(pin):
    print('Interrupt by LDR:', pin)
    pin_led.on()
    sleep(1)
    pin_led.off()

# Interrupt trigger when light level changes (rising or falling)
pin_ldr.irq(trigger=Pin.IRQ_RISING | Pin.IRQ_FALLING, handler=interrupt_ldr)

#####################################
###### MAIN ROUTINE
def main():
    while True:
        # LED stays off unless triggered by interrupt
        pin_led.off()
        sleep(10)

#####################################
###### EXECUTE MAIN ROUTINE
if __name__ == '__main__':
    main()