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

const int potPin = A0;    // Pin untuk potensiometer
const int redPin = 2;     // Pin untuk LED merah
const int yelPin = 3;     // Pin untuk LED kuning 
const int grePin = 4;     // Pin untuk LED hijau 

LiquidCrystal_I2C lcd(0x27, 16, 2);  // Alamat I2C LCD: 0x27, 16 kolom, 2 baris

void setup() {
  pinMode(redPin, OUTPUT);
  pinMode(grePin, OUTPUT);
  pinMode(yelPin, OUTPUT);

  // Inisialisasi LCD
  lcd.begin(16, 2);
  lcd.print("Persentase:");
}

void loop() {
  int potValue = analogRead(potPin);        // Membaca nilai potensiometer
  int brightness = map(potValue, 0, 1023, 0, 100);  // Mapping nilai ke persentase
  analogWrite(redPin, map(brightness, 0, 100, 0, 255));  // Mengatur kecerahan lampu LED

  // Menyala berdasarkan nilai persentase
  if (brightness <= 33) {
      digitalWrite(grePin, HIGH);
      digitalWrite(yelPin, LOW);
      digitalWrite(redPin, LOW);
    } else if (brightness >= 34 && brightness <= 66) {
      digitalWrite(grePin, HIGH);
      digitalWrite(yelPin, HIGH);
      digitalWrite(redPin, LOW);
    } else if (brightness >= 67 && brightness <= 99) {
      digitalWrite(grePin, HIGH);
      digitalWrite(yelPin, HIGH);
      digitalWrite(redPin, HIGH);
    } else {
      // Kedipkan ketiga LED
      digitalWrite(grePin, HIGH);
      digitalWrite(yelPin, HIGH);
      digitalWrite(redPin, HIGH);
      delay(500);
      digitalWrite(grePin, LOW);
      digitalWrite(yelPin, LOW);
      digitalWrite(redPin, LOW);
      delay(500);
    }


  // Menampilkan persentase di LCD
  lcd.setCursor(0, 1);
  lcd.print("   ");  // Menghapus nilai sebelumnya
  lcd.setCursor(0, 1);
  lcd.print(brightness);
  lcd.print("%");

  delay(100);  // Memberikan sedikit keterlambatan agar tampilan stabil
}