// https://wokwi.com/projects/426781912952646657

#define PORTD_CONFIG (0xFF)

#define SEG_0  (0x40)  // 01000000 - All segments except g (a, b, c, d, e, f)
#define SEG_1  (0x79)  // 01111001 - Only segments b and c
#define SEG_2  (0x24)  // 00100100 - Segments a, b, d, e, g
#define SEG_3  (0x30)  // 00110000 - Segments a, b, c, d, g
#define SEG_4  (0x19)  // 00011001 - Segments b, c, f, g
#define SEG_5  (0x12)  // 00010010 - Segments a, c, d, f, g
#define SEG_6  (0x02)  // 00000010 - Segments a, c, d, e, f, g
#define SEG_7  (0x78)  // 01111000 - Only segments a, b, c
#define SEG_8  (0x00)  // 00000000 - All segments a-g
#define SEG_9  (0x10)  // 00010000 - Segments a, b, c, d, f, g  
#define STOP_DISP     (0xFF)
#define BUTTON1       (8)
#define SEG_DEL       delay(500)
int count = 0;

void setup() {

  DDRD = PORTD_CONFIG;
  pinMode(BUTTON1, INPUT);
  pinMode(0, OUTPUT);
  pinMode(1, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, OUTPUT);

  PORTD = STOP_DISP;
}

void loop() {
  
  unsigned int seg_disp[] = {SEG_0, SEG_1, SEG_2, SEG_3, SEG_4, SEG_5, SEG_6, SEG_7, SEG_8, SEG_9};
  bool buttonState = LOW;
  bool lastButtonState = LOW;

  // Read button state with debouncing
  buttonState = digitalRead(BUTTON1);
 
  if (buttonState != lastButtonState) {
    SEG_DEL;
 
    buttonState = digitalRead(BUTTON1);
  }
  
  // Check for button press (LOW to HIGH transition)
  if (buttonState == HIGH && lastButtonState == LOW) {
    count++;
    if (count >= 4) count = 0;
  }
  
  // Update the last button state
  lastButtonState = buttonState;
 switch (count) {
    case 0:  
      for (int i = 0; i < 10; i++) {
        PORTD = seg_disp[i] | 0x80;
        SEG_DEL;
      }
      break;

    case 1:  
      for (int i = 1; i <= 9; i += 2) {
        PORTD = seg_disp[i];
        SEG_DEL;
      }
      break;

    case 2:  
      for (int i = 9; i >= 0; i--) {
        PORTD = seg_disp[i];
        SEG_DEL;
      }
      break;

    case 3:  
      for (int i = 0; i <= 8; i += 2) {
        PORTD = seg_disp[i];
        SEG_DEL;
      }
      break;

    default:
      count = 0;
      break;
  }
}