#define PIN_LED_RED 13
#define PIN_LED_GREEN 12
#define PIN_LED_BLUE 11

#define PIN_BUTTON_RED 5
#define PIN_BUTTON_GREEN 4
#define PIN_BUTTON_BLUE 3

#define OFF 0
#define RED 1
#define GREEN 2
#define BLUE 3

// Functions
void checkTimePassed(unsigned long start, unsigned long time, byte PIN_LED);
void turnOff();

// Variables
byte ledState = 0;
unsigned long startRed = 0;
unsigned long timeRed = 3000;
unsigned long startGreen = 0;
unsigned long timeGreen = 2000;
unsigned long startBlue = 0;
unsigned long timeBlue = 1000;

void setup() {
  Serial.begin(9600);
  pinMode(PIN_LED_RED, OUTPUT);
  pinMode(PIN_LED_GREEN, OUTPUT);
  pinMode(PIN_LED_BLUE, OUTPUT);
  pinMode(PIN_BUTTON_RED, INPUT);
  pinMode(PIN_BUTTON_GREEN, INPUT);
  pinMode(PIN_BUTTON_BLUE, INPUT);
  digitalWrite(PIN_LED_RED, LOW);
  digitalWrite(PIN_LED_GREEN, LOW);
  digitalWrite(PIN_LED_BLUE, LOW);
}

void loop() {

  if (!digitalRead(PIN_BUTTON_RED)) {
    startRed = millis();
    ledState = RED;
    turnOff();
  }
  if (!digitalRead(PIN_BUTTON_GREEN)) {
    startGreen = millis();
    ledState = GREEN;
    turnOff();
  }
  if (!digitalRead(PIN_BUTTON_BLUE)) {
    startBlue = millis();
    ledState = BLUE;
    turnOff();
  }


  switch (ledState) {
    case RED:
      checkTimePassed(startRed,timeRed,PIN_LED_RED);
      break;
    case GREEN:
      checkTimePassed(startGreen,timeGreen,PIN_LED_GREEN);
      break;
    case BLUE:
     checkTimePassed(startBlue,timeBlue,PIN_LED_BLUE);
      break;
    case OFF:
      turnOff ();
      break;
    default:
      break;
  }
}

void turnOff() {
  digitalWrite(PIN_LED_RED, LOW);
  digitalWrite(PIN_LED_GREEN, LOW);
  digitalWrite(PIN_LED_BLUE, LOW);

}

void checkTimePassed(unsigned long start, unsigned long time, byte PIN_LED) {
  /* als tijd voorbij, dan gaat led uit
    start = startred, startgreen of startblue
    time = timered, timegreen of timeblue
  */
  if ((millis() - start) > time) {
    ledState = OFF;
  } else {
    digitalWrite(PIN_LED, HIGH);
  }
}