// SENSOR KETINGGIAN AIR atau WADUK
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2); 

// LED and sensor pins
const int led1 = 1;
const int led2 = 2;
const int led3 = 3;
const int trig = 4;
const int echo = 5;

long duration, distance;

void setup() {
  lcd.init();                  
  lcd.backlight();             
  pinMode(trig, OUTPUT);       
  pinMode(echo, INPUT);        
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
}

void loop() {
  digitalWrite(trig, LOW);
  delayMicroseconds(2);
  digitalWrite(trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig, LOW);
  
  duration = pulseIn(echo, HIGH);
  distance = (duration / 2) * 0.034; 

  lcd.clear();
  lcd.setCursor(3, 0);
  lcd.print("PENGUKURAN");
  lcd.setCursor(9, 1);
  lcd.print(distance);
  lcd.print(" CM");

  if (distance >= 100 && distance <= 200) {
    lcd.setCursor(2, 1);
    lcd.print("SEDANG");
    digitalWrite(led1, HIGH);
    digitalWrite(led2, LOW);
    digitalWrite(led3, LOW);
  } else if (distance > 200 && distance <= 300) {
    lcd.setCursor(2, 1);
    lcd.print("SIAGA");
    digitalWrite(led1, LOW);
    digitalWrite(led2, HIGH);
    digitalWrite(led3, LOW);
  } else if (distance > 300) {
    lcd.setCursor(2, 1);
    lcd.print("BAHAYA");
    digitalWrite(led1, LOW);
    digitalWrite(led2, LOW);
    digitalWrite(led3, HIGH);
  }
  
  delay(1000); // Delay
}