const int data = 6;   // Data pin for the first shift register
const int stcp = 7;   // Latch pin for the first shift register
const int shcp = 8;   // Clock pin for the first shift register
const int ds = 21;    // Data pin for the second shift register
const int stcpi = 23; // Latch pin for the second shift register
const int shcpi = 22; // Clock pin for the second shift register

int prevState = LOW;  // Stores previous button state for polling
volatile bool buttonPressed = false;  // Interrupt flag for ISR button
unsigned long lastDebounce = 0;  // Debouncing timer
const unsigned long debounceDelay = 200;  // Debouncing delay (200ms)

int x = 0;  
int y = 0;  
const int button = 17;  
const int button_2 = 16;  

void local() {
  unsigned long currentTime = millis();
  if (currentTime - lastDebounce > debounceDelay) {
    lastDebounce = currentTime;
    buttonPressed = true;
  }
}

void setup() {
  // Setup for Serial and pin modes
  Serial.begin(115200);
  pinMode(button, INPUT);
  pinMode(button_2, INPUT);
  pinMode(data, OUTPUT);
  pinMode(stcp, OUTPUT);
  pinMode(shcp, OUTPUT);
  pinMode(ds, OUTPUT);
  pinMode(stcpi, OUTPUT);
  pinMode(shcpi, OUTPUT);
  attachInterrupt(digitalPinToInterrupt(button), local, RISING);
}

void loop() {
  if (buttonPressed == true) {
    buttonPressed = false;
    x++;
    if (x > 6) {
      x = 0;
    }
    incrementNum(x);  
    delay(10);  
  }
  int state = digitalRead(button_2);
  unsigned long currentTime = millis();

  if (state == HIGH && prevState == LOW && (currentTime - lastDebounce > debounceDelay)) {
    lastDebounce = currentTime;  // Update debounce time
    y++;  
    if (y > 6) {
      y = 0;
    }
    increment(y);  
    delay(10);
  }

  prevState = state;  // Update previous state for the next loop
}
void incrementNum(int num) {
  digitalWrite(stcp, LOW);
  if (num == 0) {
    shiftOut(data, shcp, LSBFIRST, 0B11111100);
  } else if (num == 1) {
    shiftOut(data, shcp, LSBFIRST, 0B01100000);
  } else if (num == 2) {
    shiftOut(data, shcp, LSBFIRST, 0B11011010);
  } else if (num == 3) {
    shiftOut(data, shcp, LSBFIRST, 0B11110010);
  } else if (num == 4) {
    shiftOut(data, shcp, LSBFIRST, 0B01100110);
  } else if (num == 5) {
    shiftOut(data, shcp, LSBFIRST, 0B10110110);
  } else if (num == 6) {
    shiftOut(data, shcp, LSBFIRST, 0B10111110);
  }
  digitalWrite(stcp, HIGH);  // Latch the data to display
}

// Function to update the second seven-segment display 
void increment(int num) {
  digitalWrite(stcpi, LOW);
  if (num == 0) {
    shiftOut(ds, shcpi, LSBFIRST, 0);  // Clear display
  } else if (num == 1) {
    shiftOut(ds, shcpi, LSBFIRST, 0B11101110);  // Display 'A'
  } else if (num == 2) {
    shiftOut(ds, shcpi, LSBFIRST, 0B00111110);  // Display 'B'
  } else if (num == 3) {
    shiftOut(ds, shcpi, LSBFIRST, 0B10011100);  // Display 'C'
  } else if (num == 4) {
    shiftOut(ds, shcpi, LSBFIRST, 0B01111010);  // Display 'D'
  } else if (num == 5) {
    shiftOut(ds, shcpi, LSBFIRST, 0B10011110);  // Display 'E'
  } else if (num == 6) {
    shiftOut(ds, shcpi, LSBFIRST, 0B10001110);  // Display 'F'
  }
  digitalWrite(stcpi, HIGH);  // Latch the data to display
}