#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <cs50.h>

#include "bmp.h"

int main(int argc, char *argv[])
{
    // ensure proper usage
    if (argc != 2)
    {
        fprintf(stderr, "Usage: ./recover filename\n");
        return 1;
    }

    // assigns file name to variable (should be null if not card.raw)
    char *infile = argv[1];

    // opens card file with variable name
    FILE *inptr = fopen(infile, "r");
    if (!inptr)
    {
        fprintf(stderr, "Could not open %s.\n", infile);
        return 1;
    }

    bool found_first_jpg = false;
    int n = 0;
    BYTE buffer[512];
    FILE *new_jpg_ptr;


    while (fread(buffer, 512, 1, inptr) != 0x00)
    {
        if (buffer[0] == 0xff && buffer[1] == 0xd8 && buffer[2] == 0xff && (buffer[3] & 0xf0) == 0xe0)
        {
            char filename[8];
            if (found_first_jpg == false)
            {
                found_first_jpg = true;
                sprintf(filename, "%03i.jpg", n++);
                new_jpg_ptr = fopen(filename, "w");
                if (new_jpg_ptr == NULL)
                {
                    return 1;
                }
                fwrite(buffer, 512, 1, new_jpg_ptr);
            }
            else
            {
                fclose(new_jpg_ptr);
                sprintf(filename, "%03i.jpg", n++);
                new_jpg_ptr = fopen(filename, "w");
                if (new_jpg_ptr == NULL)
                {
                    return 1;
                }
                fwrite(buffer, 512, 1, new_jpg_ptr);
            }
        }
        else
        {
            if (found_first_jpg)
            {
                fwrite(buffer, 512, 1, new_jpg_ptr);
            }
        }
    }

    fclose(new_jpg_ptr);
    fclose(inptr);
}