// Deklarasi PIN
const int triggerPin = 2;
const int echoPin = 4;
const int ledRedPin = 32;
const int ledYellowPin = 35;
const int ledGreenPin = 34;

// Set Threshold
const int thresholdSafe = 15;
const int thresholdUnsafe = 50;

void setup() {
  pinMode(triggerPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ledRedPin, OUTPUT);
  pinMode(ledYellowPin, OUTPUT);
  pinMode(ledGreenPin, OUTPUT);
  Serial.begin(9600);
}

// Convert distance menjadi centimeter
float readDistanceCM() {
  digitalWrite(triggerPin, LOW);
  delayMicroseconds(2);
  digitalWrite(triggerPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(triggerPin, LOW);
  int duration = pulseIn(echoPin, HIGH);
  return duration * 0.034 / 2;
}

void loop() {
  // Deklarasi Jarak dalam cm
  float distance = readDistanceCM();
  
  Serial.println("--------------------");
  // Kondisi untuk menyalakan LED sesuai dengan ketinggian air
  if (distance <= thresholdSafe) {
    digitalWrite(ledRedPin, LOW);
    digitalWrite(ledYellowPin, LOW);
    digitalWrite(ledGreenPin, HIGH);
    Serial.println("Tinggi Air:\nAman");
  } else if (distance > thresholdSafe && distance <= thresholdUnsafe) {
    digitalWrite(ledRedPin, LOW);
    digitalWrite(ledYellowPin, HIGH);
    digitalWrite(ledGreenPin, LOW);
    Serial.println("Tinggi Air:\nWaspada! Mendekati batas air berbahaya!");
  } else {
    digitalWrite(ledRedPin, HIGH);
    digitalWrite(ledYellowPin, LOW);
    digitalWrite(ledGreenPin, LOW);
    Serial.println("Tinggi Air\nBERBAHAYA! KETINGGIAN AIR MELEBIHI BATAS AMAN");
  }
  Serial.println("--------------------");

  delay(1000);
}