#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <pwd.h>
#include <signal.h>
#include <unistd.h>

main(int argc, char **argv)
{

    struct passwd *userlist;
    int count, usernumber, len1;
    FILE *tmp, *stmp, *profile;
    char *commentfield, *username, *userdir, *home;
    char reply;

    commentfield = (char *)malloc(1024*sizeof(char));
    username = (char *)malloc(8*sizeof(char));
    userdir = (char *)malloc(256*sizeof(char));
    home = (char *)malloc(256*sizeof(char));

    if (argc!=4)
    {
        printf("jak korzystac : %s [directory] [nazwa uzytkownika] [komentarz]\n", argv[0]);
        exit(1);
    }

    if( (strlen(argv[2]) < 5) || (strlen(argv[2]) > 8) )
    {
        printf("Nazwa uzytkownika musi miescic sie w zakresie od 5 do 8 znakow :( \n");
        exit(1);
    }

    signal(SIGHUP, SIG_IGN);
    signal(SIGINT, SIG_IGN);

    setpwent();

    count = 0;

    while((userlist = getpwent()) != NULL)
    {
        if(count < userlist->pw_uid)
        {
            count = userlist->pw_uid ;
            usernumber = count + 1;
        }
    }
    printf("usernumber : %d\n", usernumber);

    endpwent();

    sprintf(commentfield,"%s", argv[3]);
    sprintf(username, "%s", argv[2]);
    sprintf(userdir, "%s", argv[1]);
    sprintf(home, "/%s/%s", argv[1], argv[2]);



    printf("\n Sprawdz czy wszystko gra: \n");
    printf("----------------------------------------------------");
    printf("\n Nazwa uzytkownika      :\t %s", username);
    printf("\n Directory              :\t %s", home);
    printf("\n Komentarz              :\t %s", commentfield);
    printf("\n----------------------------------------------------\n\n");

    printf("Czy wszystko sie zgadza? t/n: ");
    scanf("%c", &reply);

    if(reply != 't')
    {
        printf("\n Opuszczam program. Nie wpisano 't'\n");
        exit(1);
    }

    tmp = fopen("/etc/passwd", "a");
    if (tmp == NULL)
    {
        printf("\nBrak dostepu\n");
        exit(1);
    }
    fprintf(tmp, "%s:x:%d:1:%s:%s:/bin/bash\n", username, usernumber, commentfield, home);
    fclose(tmp);



    stmp = fopen("/etc/shadow", "a");
    if (stmp == NULL)
    {
        printf("\nBrak dostepu\n");
        exit(1);
    }
    fprintf(stmp, "%s:*LK*:::::::\n", username);
    fclose(stmp);

    mkdir(home, 0755);
    chdir(home);


    profile = fopen(".profile", "a");
    fprintf(profile, "stty istrip\n");
    fprintf(profile, "PATH=/bin:/usr/bin:/usr/local/bin:/usr/share/bin:.\n");
    fprintf(profile, "export PATH\n");
    fprintf(profile, "\n\n");
    fclose(profile);

    chown(home, usernumber, 1);
    chown(".profile", usernumber, 1);
    chmod(".profile", 0644);


    printf("\n\nSukces!!\n Teraz ustaw haslo: ");
    execl("/usr/bin/passwd", "passwd", username, NULL);
    printf("\n\n Sukces!! Haslo ustawione :)\n\n");

}