#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#define DATA_PORT 0x378 /* parallel port base address */
#define STATUS_PORT (DATA_PORT + 1)
#define CONTROL_PORT (DATA_PORT + 2)

unsigned char status, data;

// Array to hold bit patterns for each digit
unsigned char BCD_values[10] = {
    0b00000000, // digit 0
    0b00000001, // digit 1
    0b00000010, // digit 2
    0b00000011, // digit 3
    0b00000100, // digit 4
    0b00000101, // digit 5
    0b00000110, // digit 6
    0b00000111, // digit 7
    0b00001000, // digit 8
    0b00001001  // digit 9
};

int main()
{
    if (ioperm(DATA_PORT, 3, 1))
    {
        fprintf(stderr, "Access denied to ports\n");
        exit(1);
    }

    int button_presses = 0;
    // int previous_status = 0;

    while (1)
    {
        status = inb(STATUS_PORT); // Read from status port

        // Check if the button is pressed (bit 2)
        if ((status & 0b00010000))
        {
            button_presses++; // Increment button press counter
            printf("Button pressed! Total presses: %d\n", button_presses);
            data = BCD_values[button_presses % 10]; // Get BCD value for current digit
            outb(data, DATA_PORT);                  // Display the digit
            while ((status & 0b00010000))
            {
                usleep(100000);
            }
        }
    }

    ioperm(DATA_PORT, 3, 0); // Release the ports
    return 0;
}