// Muhammad Azif Zain Rizky / 18
#define ECHO_PIN 2
#define TRIG_PIN 15
#define ledred 5
#define ledyellow 21
#define ledgreen 19
#define buzzerPin 4

void setup() {
  Serial.begin(115200);
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(ledred, OUTPUT);
  pinMode(ledyellow, OUTPUT);
  pinMode(ledgreen, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
}

void loop() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  int duration = pulseIn(ECHO_PIN, HIGH);
  float distance = duration * 0.034 / 2;

  Serial.print("Jarak: ");
  Serial.println(distance);

  delay(100);

  if (distance > 200) {
    digitalWrite(ledred, LOW);
    digitalWrite(ledyellow, LOW);
    digitalWrite(ledgreen, HIGH);
    digitalWrite(buzzerPin, LOW);
    Serial.print("Jarak Aman ");
  } else if (distance < 200 && distance > 100) {
    digitalWrite(ledred, LOW);
    digitalWrite(ledyellow, HIGH);
    digitalWrite(ledgreen, LOW);
    digitalWrite(buzzerPin, LOW);
    Serial.print("Jarak Siaga 1 ");
  } else if (distance < 100) {
    digitalWrite(ledred, HIGH);
    digitalWrite(ledyellow, LOW);
    digitalWrite(ledgreen, LOW);
    digitalWrite(buzzerPin, HIGH);
    
    Serial.print("Bahaya Akan Tiba, Alarm Berbunyi !!!");
  }
  
  delayMicroseconds(1000);
}