#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 20, 4);

uint8_t band_encoder_CLK = 2;
uint8_t band_encoder_DT = 4;
uint8_t band_encoder_SW = 5;

uint8_t c_encoder_CLK = 3;
uint8_t c_encoder_DT = 6;
uint8_t c_encoder_SW = 7;

uint8_t band_counter = 0;
uint8_t c_counter = 0;

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

  // Initialize encoder pins
  pinMode(band_encoder_CLK, INPUT);
  pinMode(band_encoder_DT, INPUT);
  pinMode(band_encoder_SW, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(band_encoder_CLK), readBandEncoder, FALLING);

  pinMode(c_encoder_CLK, INPUT);
  pinMode(c_encoder_DT, INPUT);
  pinMode(c_encoder_SW, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(c_encoder_CLK), readCEncoder, FALLING);
}

void readBandEncoder() {
  int dtValue = digitalRead(band_encoder_DT);
  if (dtValue == HIGH) {
    if (band_counter < 9){
      band_counter++;
    }   
  }

  if (dtValue == LOW) {
    if (band_counter > 0){
      band_counter--;
    }   
  }
}

void readCEncoder() {
  int dtValue = digitalRead(c_encoder_DT);
  if (dtValue == HIGH) {
    if (c_counter < 127){
      c_counter++;
    }   
  }

  if (dtValue == LOW) {
    if (c_counter > 0){
      c_counter--;
    }   
  }
}

// Get the counter value, disabling interrupts.
// This make sure readEncoder() doesn't change the value
// while we're reading it.
int getBandCounter() {
  int result;
  noInterrupts();
  result = band_counter;
  interrupts();
  return result;
}

int getCCounter() {
  int result;
  noInterrupts();
  result = c_counter;
  interrupts();
  return result;
}


void resetBandCounter() {
  noInterrupts();
  band_counter = 0;
  interrupts();
}

void resetCCounter() {
  noInterrupts();
  c_counter = 0;
  interrupts();
}

void loop() {
  lcd.setCursor(0, 0);
  lcd.print('                  ');
  lcd.setCursor(0, 0);
  lcd.print('Band : ' +getBandCounter());
  lcd.setCursor(0, 1);
  lcd.print('                  ');
  lcd.setCursor(0, 1);
  lcd.print('C : '+getCCounter());
  
  if (digitalRead(band_encoder_SW) == LOW) {
    resetBandCounter();
  }
  if (digitalRead(c_encoder_SW) == LOW) {
    resetCCounter();
  }
}