#include <Arduino.h>

#define LED_1_PIN 19 // most left
#define LED_2_PIN 18
#define LED_3_PIN 5
#define LED_4_PIN 17
#define LED_5_PIN 16 // most right

#define BTN_LEFT_PIN 22
#define BTN_RIGHT_PIN 23

#define LED_MODE_OFF 0
#define LED_MODE_LEFT_TO_RIGHT 1
#define LED_MODE_RIGHT_TO_LEFT 2
#define DELAY_TIME 100

// Globale Variablen
int led_array[5] = {LED_1_PIN, LED_2_PIN, LED_3_PIN, LED_4_PIN, LED_5_PIN};
int direction = LED_MODE_OFF;

void setup()
{
  // put your setup code here, to run once:
  pinMode(BTN_LEFT_PIN, INPUT_PULLDOWN);
  pinMode(BTN_RIGHT_PIN, INPUT_PULLDOWN);
  // LEDS
  for (int i = 0; i < 5; i++)
  {
    pinMode(led_array[i], OUTPUT);
  }
}

void loop()
{
  // put your main code here, to run repeatedly

  if (HIGH == digitalRead(BTN_LEFT_PIN))
  {
    direction = LED_MODE_RIGHT_TO_LEFT;
  }

  if (HIGH == digitalRead(BTN_RIGHT_PIN))
  {
    direction = LED_MODE_LEFT_TO_RIGHT;
  }

  run_led_chaser(direction);
}

void run_led_chaser(int direction)
{
  if (LED_MODE_LEFT_TO_RIGHT == direction)
  {
    for (int i = 0; i < 5; i++)
    {
      digitalWrite(led_array[i], HIGH);
      delay(DELAY_TIME);
      digitalWrite(led_array[i], LOW);
    }
  }
  else if (LED_MODE_RIGHT_TO_LEFT)
  {
    for (int i = 4; i >= 0; i--)
    {
      digitalWrite(led_array[i], HIGH);
      delay(DELAY_TIME);
      digitalWrite(led_array[i], LOW);
    }
  }
}