import machine
import time

# Set up the GPIO pins
leds = [machine.Pin(i, machine.Pin.OUT, machine.Pin.PULL_DOWN) for i in range(14, 17)]  # Set up LEDs
led_states = [False] * 3  # Set initial state of LEDs
car_status = ["STOP","WAIT","GO"]
button = machine.Pin(18, machine.Pin.IN, machine.Pin.PULL_DOWN)  # Set up pushbuttons

# Define functions to turn on and off LEDs
def turn_on_led(led_num):
    if led_num < 1 or led_num > 4:
        return

    leds[led_num - 1].value(1)
    print (car_status[led_num-1])
    led_states[led_num - 1] = True

def turn_off_led(led_num):
    if led_num < 1 or led_num > 4:
        return

    leds[led_num - 1].value(0)
    led_states[led_num - 1] = False

# Define function to start and end traffic jam
def start_traffic_jam():
    for led in leds:
        led.value(0)  # Turn off all LEDs

    for i in range(4):  # Turn on LEDs one by one, simulating traffic jam
        turn_on_led(i)
        turn_off_led(i-1)
        time.sleep(2)


def end_traffic_jam():
    for led in leds:
        led.value(0)  # Turn off all LEDs
    led.value(1)  # Turn on green LED

# Main loop
while True:
    # Check if any of the push buttons are pressed
        end_traffic_jam()
        if button.value():

            print("Traffic jam started")
            start_traffic_jam()
            end_traffic_jam()
            print("Traffic jam ended")