import machine
import time

# --- Pin Configuration ---

# Define the GPIO pins for the 8 LEDs
# Using the recommended stable output pins
led_pins_gpio = [18, 19, 12, 14, 13,21,4, 2]
led_pins = []


# Define GPIO pins for the push buttons
# Using input-only pins which require external pull-down resistors
entrance_button_pin = machine.Pin(34, machine.Pin.IN)
exit_button_pin = machine.Pin(35, machine.Pin.IN)

# --- System Variables ---
car_count = 0
max_cars = 8

# Debouncing variables to prevent multiple counts from a single press
last_entrance_press_time = 0
last_exit_press_time = 0
debounce_delay_ms = 200 # 200 milliseconds

# --- Setup ---
def setup():
    """Initializes the GPIO pins for the LEDs."""
    print("System initializing...")
    for pin_num in led_pins_gpio:
        # Configure each LED pin as an output
        led_pins.append(machine.Pin(pin_num, machine.Pin.OUT))
    # Initially, turn all LEDs off
    update_leds()
    print("System ready. Waiting for input.")

def update_leds():
    """Updates the state of the 8 LEDs based on the car_count."""
    print(f"Updating LEDs for car count: {car_count}")
    for i in range(max_cars):
        if i < car_count:
            led_pins[i].on() # Turn LED on
        else:
            led_pins[i].off() # Turn LED off

# --- Main Loop ---
def loop():
    """The main logic loop that runs continuously."""
    global car_count, last_entrance_press_time, last_exit_press_time

    current_time = time.ticks_ms()

    # --- Check Entrance Button ---
    # The pin reads 1 when the button is pressed because of the external pull-down resistor setup
    if entrance_button_pin.value() == 1 and time.ticks_diff(current_time, last_entrance_press_time) > debounce_delay_ms:
        last_entrance_press_time = current_time # Record the time of the press
        if car_count < max_cars:
            car_count += 1
            print(f"Car entered. Total cars: {car_count}")
            update_leds()
        else:
            print("Garage is full. Cannot add more cars.")

    # --- Check Exit Button ---
    # The pin reads 1 when the button is pressed
    if exit_button_pin.value() == 1 and time.ticks_diff(current_time, last_exit_press_time) > debounce_delay_ms:
        last_exit_press_time = current_time # Record the time of the press
        if car_count > 0:
            car_count -= 1
            print(f"Car exited. Total cars: {car_count}")
            update_leds()
        else:
            print("Garage is empty. Cannot remove more cars.")

    # Small delay to make the simulation stable
    time.sleep_ms(10)

# --- Program Start ---
if __name__ == "__main__":
    setup()
    while True:
        loop()