// PROJECT : Pengukuran Volume Air Otomatis

const int TRIGPIN = 8;
const int ECHOPIN = 7;

const int LED1 = 13; // Air habis
const int LED2 = 12; // Air setengah
const int LED3 = 11; // Air penuh

const int BUZZER = 10;

long timer;
int jarak;

void setup() {
  Serial.begin(9600);

  pinMode(TRIGPIN, OUTPUT);
  pinMode(ECHOPIN, INPUT);

  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);

  pinMode(BUZZER, OUTPUT);
}

void loop() {

  digitalWrite(TRIGPIN, LOW);
  delayMicroseconds(2);

  digitalWrite(TRIGPIN, HIGH);
  delayMicroseconds(10);

  digitalWrite(TRIGPIN, LOW);

  timer = pulseIn(ECHOPIN, HIGH);
  jarak = timer / 58;

  Serial.print("Ketinggian air = ");
  Serial.print(jarak);
  Serial.println(" cm");

  // Air penuh
  if (jarak < 20) {
    Serial.println("Air sudah penuh");

    digitalWrite(LED1, LOW);
    digitalWrite(LED2, LOW);
    digitalWrite(LED3, HIGH);

    tone(BUZZER, 1000);
    delay(500);
    noTone(BUZZER);
  }

  // Air setengah
  else if (jarak < 215) {
    Serial.println("Air masih setengah");

    digitalWrite(LED1, LOW);
    digitalWrite(LED2, HIGH);
    digitalWrite(LED3, LOW);

    noTone(BUZZER);
  }

  // Air habis
  else {
    Serial.println("Air habis");

    digitalWrite(LED1, HIGH);
    digitalWrite(LED2, LOW);
    digitalWrite(LED3, LOW);

    tone(BUZZER, 2000);
    delay(200);
    noTone(BUZZER);
  }

  delay(1000);
}