/*
 * Created by ArduinoGetStarted.com
 *
 * This example code is in the public domain
 *
 * Tutorial page: https://arduinogetstarted.com/tutorials/arduino-rotary-encoder-led
 */



#define CLK_PIN 2
#define DT_PIN 3
#define SW_PIN 4
#define LED_PIN 5

#define DIRECTION_CW 0   // clockwise direction
#define DIRECTION_CCW 1  // counter-clockwise direction

int counter = 0;
int direction = DIRECTION_CW;
int CLK_state;
int prev_CLK_state;
int brightness = 125;  // middle value

void setup() {
  Serial.begin(9600);

  // configure encoder pins as inputs
  pinMode(CLK_PIN, INPUT);
  pinMode(DT_PIN, INPUT);

  // read the initial state of the rotary encoder's CLK pin
  prev_CLK_state = digitalRead(CLK_PIN);
  pinMode(LED_PIN, OUTPUT);
}

void loop() {

  // read the current state of the rotary encoder's CLK pin
  CLK_state = digitalRead(CLK_PIN);

  // If the state of CLK is changed, then pulse occurred
  // React to only the rising edge (from LOW to HIGH) to avoid double count
  if (CLK_state != prev_CLK_state && CLK_state == HIGH) {
    // if the DT state is HIGH
    // the encoder is rotating in counter-clockwise direction => decrease the counter
    if (digitalRead(DT_PIN) == HIGH) {
      direction = DIRECTION_CCW;
      counter--;
      brightness -= 10;  // you can change this value
    } else {
      // the encoder is rotating in clockwise direction => increase the counter
      direction = DIRECTION_CW;
      counter++;
      brightness += 10;  // you can change this value
    }

    if (brightness < 0)
      brightness = 0;
    else if (brightness > 255)
      brightness = 255;

    // sets the brightness of LED according to the counter
    analogWrite(LED_PIN, brightness);

    Serial.print("COUNTER: ");
    Serial.print(counter);
    Serial.print(" | BRIGHTNESS: ");
    Serial.println(brightness);
  }

  // save last CLK state
  prev_CLK_state = CLK_state;
}