#define LED_1 19
#define LED_2 18
#define LED_3 5
#define PIN_TRIG 15
#define PIN_ECHO 2

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  pinMode(LED_1, OUTPUT);
  pinMode(LED_2, OUTPUT);
  pinMode(LED_3, OUTPUT);
  pinMode(PIN_TRIG, OUTPUT);
  pinMode(PIN_ECHO, INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(PIN_TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(PIN_TRIG, LOW);

  // Read the result:
  int duration = pulseIn(PIN_ECHO, HIGH);
  int jarak = duration / 58;  
  String kata = String("Distance in CM: ") + jarak;
  Serial.println(kata);
  menyalakanLampu(jarak);  
  delay(1000); // this speeds up the simulation
}

void menyalakanLampu (int jarak) {
  if ( jarak > 200 ) {
    digitalWrite(LED_1, HIGH);
    digitalWrite(LED_2, HIGH);
    digitalWrite(LED_3, HIGH);
  } else if ( jarak > 100 ) {
    digitalWrite(LED_1, HIGH);
    digitalWrite(LED_2, HIGH);
    digitalWrite(LED_3, LOW);
  } else if (jarak > 50 ) {
    digitalWrite(LED_1, HIGH);
    digitalWrite(LED_2, LOW);
    digitalWrite(LED_3, LOW);
  } else {
    digitalWrite(LED_1, LOW);
    digitalWrite(LED_2, LOW);
    digitalWrite(LED_3, LOW);
  }
};