#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);

#define ENCODER_CLK 2
#define ENCODER_DT 3
#define ENCODER_SW 4

int counter = 0;

void setup() {
  //inisialisasi LCD
  lcd.init();
  lcd.backlight();

  //inisialisasi LED
  pinMode(11, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(13, OUTPUT);
  digitalWrite(11, LOW);
  digitalWrite(12, LOW);
  digitalWrite(13, LOW);

  //inisialisasi encoder
  pinMode(ENCODER_DT, INPUT);
  pinMode(ENCODER_SW, INPUT_PULLUP);
  pinMode(ENCODER_CLK, INPUT);
  attachInterrupt(digitalPinToInterrupt(ENCODER_CLK), readEncoder, FALLING);
}

void readEncoder(){
  int dtValue = digitalRead(ENCODER_DT);
  if (dtValue == HIGH) {
  counter++; //clockwise
  }
  if (dtValue == LOW) {
  counter--; //counterclockwise
  }
}

int getCounter() {
  int result;
  noInterrupts();
  result = counter;
  interrupts();
  return result;
}

void resetCounter(){
  noInterrupts();
  counter = 0;
  interrupts();
}

void loop(){
  lcd.setCursor(3,0);
  lcd.print("Counter:");
  lcd.setCursor(7,1);
  lcd.print(getCounter());
  lcd.print("          ");
  if(digitalRead (ENCODER_SW)==LOW){
    resetCounter();
  }

  //counter++
  if(counter == 1){
  digitalWrite(13, HIGH);
  }
  else if (counter == 2){
  digitalWrite(12, HIGH);
  digitalWrite(13, LOW);
 }
  else if (counter ==3){
  digitalWrite(11, HIGH);
  digitalWrite(12, LOW);
 }
 else if (counter == 4){
  counter = 0;
 }
 else{
   digitalWrite(13, LOW);
   digitalWrite(12, LOW);
   digitalWrite(11, LOW);
 }

  //counter--
  if(counter == -1){
  digitalWrite(11, HIGH);
  }
  else if (counter == -2){
  digitalWrite(12, HIGH);
  digitalWrite(11, LOW);
 }
  else if (counter == -3){
  digitalWrite(13, HIGH);
  digitalWrite(12, LOW);
 }
 else if (counter == -4){
  counter = 0;
 }
 else{
   digitalWrite(11, LOW);
   digitalWrite(12, LOW);
   digitalWrite(13, LOW);
 }
}