#include <LiquidCrystal_I2C.h>
#include <Servo.h>

Servo myServo;
LiquidCrystal_I2C lcd(0x27, 16, 2);

#define TRIG_PIN 13  // Pin untuk trig ultrasonic
#define ECHO_PIN 12  // Pin untuk echo ultrasonic
int buzzer = 4;
int servoPin = 11;
int ledHijau = 2;
int ledMerah = 3;

void setup() {
  lcd.begin(16, 2);
  lcd.backlight();
  
  pinMode(buzzer, OUTPUT); // set pin buzzer sebagai output
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(ledMerah, OUTPUT);
  pinMode(ledHijau, OUTPUT);
  
  myServo.attach(servoPin);
  
  lcd.print("Water Sensor Ready");
  delay(2000);
  lcd.clear();
}

void loop() {
  long duration;
  int distance;
  int maxDistance = 400; // Maksimum jarak yang dianggap penuh (cm)

  // Trigger sensor ultrasonik
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  // Baca echo dan hitung jarak
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = duration * 0.034 / 2;

  // Konversi ke persentase ketinggian air
  int airLevel = map(distance, 0, maxDistance, 0,  400);
  
  // Tampilkan ketinggian di LCD
  lcd.setCursor(0, 0);
  lcd.print("Ketinggian: ");
  lcd.print(airLevel);
  lcd.print("cm   ");
  
  // Kontrol LED, buzzer, dan servo berdasarkan ketinggian air
  if (airLevel > 250) { // Ketinggian di atas 75%
    digitalWrite(ledMerah, HIGH);
    digitalWrite(ledHijau, LOW);
    tone(buzzer, 1000); // Menghidupkan buzzer pada frekuensi 1000 Hz
    myServo.write(90); 
  } else {
    digitalWrite(ledMerah, LOW);
    digitalWrite(ledHijau, HIGH);
    noTone(buzzer); // Mematikan buzzer
    myServo.write(0); 
  }
  
  delay(500);
}