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

#define TRIG_PIN 3
#define ECHO_PIN 2
#define SERVO_PIN 5 
#define RELAY_PIN 12

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

void setup() {
  Serial.begin(9600);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(RELAY_PIN, OUTPUT);
  myServo.attach(SERVO_PIN);
  lcd.begin(16, 2);
  lcd.init();
  lcd.backlight();
}

void loop() {
  long duration;
  float distance;

  // Trigger ultrasonic pulse
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  // Read echo pulse duration
  duration = pulseIn(ECHO_PIN, HIGH);

  // Convert duration to distance
  distance = duration * 0.034 / 2;

  // Output readings to Serial Monitor
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Display readings on LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Tinggi Air ");
  lcd.print(distance);
  lcd.print(" cm");

  // Control pump, servo, and buzzer based on water level
  if (distance > 15) { // Level LOW, turn pump on, move servo, and activate buzzer
    digitalWrite(RELAY_PIN, HIGH);
    myServo.write(90); // Move servo to 90 degrees
    lcd.setCursor(0, 1);
    lcd.print("Pompa: ON");
  } else if (distance < 5) { // Level HIGH, turn pump off, reset servo, and deactivate buzzer
    digitalWrite(RELAY_PIN, LOW);
    myServo.write(0); // Reset servo to 0 degrees
    lcd.setCursor(0, 1);
    lcd.print("Pompa: OFF ");
  }

  delay(1000);
}