// HW Pins required
#define ENCODER_SW A0         // RotaryEncoder SW Pin
#define ENCODER_DT 9          // RotaryEncoder DT Pin
#define ENCODER_CLK 11        // RotaryEncoder CLK Pin

#define DBOUNCE 200

int lastClk = HIGH;
volatile int counter = 0;

void setup() {
  Serial.begin(115200);
  pinMode(ENCODER_CLK, INPUT);
  pinMode(ENCODER_DT, INPUT);
  pinMode(ENCODER_SW, INPUT_PULLUP);
}

void loop() {
  // Encoder routine. Updates counter if they are valid
  // and if rotated a full indent
  
  static bool encoder_clicked = false;
  static uint8_t old_SW = 0;  // old Switch value
  static uint8_t new_SW = 0;  // new SW Value
  static uint8_t old_AB = 3;  // Lookup table index
  static int8_t encval = 0;   // Encoder value  
  static const int8_t enc_states[]  = {0,-1,1,0,1,0,0,-1,-1,0,0,1,0,1,-1,0}; // Lookup table
  static uint32_t last_time=0;
  uint32_t ms = millis();

  old_AB <<=2;  // Remember previous state  
 
  if (digitalRead(ENCODER_DT)) old_AB |= 0x02; // Add current state of pin A
  if (digitalRead(ENCODER_CLK)) old_AB |= 0x01; // Add current state of pin B
  
  // Encoder SW
  new_SW = analogRead(ENCODER_SW);
  if((ms-last_time) > DBOUNCE) {
    last_time = ms;
    if(new_SW != old_SW && new_SW < 100) {
      Serial.println("Switch Pressed");
      encoder_clicked = true;
    }
    old_SW = new_SW;
  }
  //

  // Encoder rotation code
  encval += enc_states[( old_AB & 0x0f )];
 
  // Update counter if encoder has rotated a full indent, that is at least 4 steps
  if( encval > 3 ) {        // Four steps forward
    counter++;              // Increase counter
    encval = 0;
    Serial.println("Rotated counterclockwise ⏪");
  }
  else if( encval < -3 ) {  // Four steps backwards
    counter--;               // Decrease counter
    encval = 0;
    Serial.println("Rotated clockwise ⏩");
  }
  if(counter > 5) counter = 5;
  if(counter < 1) counter = 1;



  encoder_clicked = false;
}