const int trigPin = 38;
const int echoPin = 39;
const int detection = 160;
const int rgreenb = 31;
const int redgb = 30;
const int rgblue = 33;


long duration;
int distance;
int reserved;
int inuse;

void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;

  if (distance <= detection) {
    rgb(0, 255, 255);
    inuse = 1;
  }
  if (distance > detection) {
    rgb(255, 0, 255);
    inuse = 0;
  }
  if (reserved == 1 && distance > detection) {
    rgb(255, 255, 0);
  }
  Serial.println(distance);
  delay(250);
}

void rgb(int r, int g, int b)//finkcia na zjednodusenie pouzivania rgb led zaradeny
{
#ifdef pre
  red = 255 - r;
  green = 255 - g;
  blue = 255 - b;
#endif
  analogWrite(redgb, r);
  analogWrite(rgreenb, g);
  analogWrite(rgblue, b);
}