/* xsh_ls.c - xsh_ls */

#include 
#include 

/*------------------------------------------------------------------------
 * xsh_ls - shell command to copy stdin to a file and to stdout
 *------------------------------------------------------------------------
 */
shellcmd xsh_ls(int nargs, char *args[])
{
        did32   dev;                    /* Device to use                */
        char    *fname;                 /* File name to map to a device */
        struct  lfdir   dir;            /* Copy oif lfs directory       */
        char    nbuf[NM_MAXLEN];        /* Buffer namespace can use for */
                                        /*   a replacement name         */
        int32   retval;                 /* Return value                 */
        bool8   loption = FALSE;        /* Did the user specify -l?     */
        int32   i;                      /* Walks through file names     */
        int32   nextarg;                /* Walks through arguments      */
        did32   fd;                     /* File desc. for remote dir.   */
        char    buf[512];               /* Buffer for remote directory  */

        /* For argument '--help', emit help about the 'ls' command      */

        if (nargs > 1 && strncmp(args[1], "--help", 7) == 0) {
                printf("Use: %s [-l] [dir]\n\n", args[0]);
                printf("Description:\n");
                printf("\tlist files in the default directory or\n");
                printf("\tthe directory specfified by dir\n");
                printf("Options:\n");
                printf("\t-l\t list file size as well as name\n");
                printf("\t--help\t display this help and exit\n");
        }

        if (nargs > 3) {
                fprintf(stderr, "Use: %s [-l] [dir]\n\n", args[0]);
                return 1;
        }
        nextarg = 1;
        if (nargs > 1 && strncmp(args[nextarg], "-l", 3) == 0) {
                loption = TRUE;
                nextarg++;
                nargs--;
        }
        if (nargs > 1) {
                if (args[nextarg][0] == '-') {
                        fprintf(stderr, "Use: %s [-l] [dir]\n\n",args[0]);
                        return 1;
                }
                fname = args[nextarg];
        } else {
                fname = ".";
        }
        dev = namrepl(fname, nbuf);
        if (dev == (did32)SYSERR) {
                fprintf(stderr, "%s: cannot access device for %s\n",
                        args[0], fname);
                return 1;
        }

        /* Handle local file system */

        if (dev == LFILESYS) {

            wait(Lf_data.lf_mutex);
            if ( ! Lf_data.lf_dirpresent ) {
                retval = read(Lf_data.lf_dskdev,(char *)&Lf_data.lf_dir,
                        LF_AREA_DIR);
                if (retval == SYSERR ) {
                        fprintf(stderr, "%s: cannot obtain directory\n",
                                args[0]);
                        signal(Lf_data.lf_mutex);
                        return 1;
                }
                if (lfscheck(&Lf_data.lf_dir) == SYSERR ) {
                        fprintf(stderr, "%s: file system uninitialized\n",
                                args[0]);
                        signal(Lf_data.lf_mutex);
                        return 1;
                }
            }
            signal(Lf_data.lf_mutex);
            memcpy((void *)&dir, (void *)&Lf_data.lf_dir, sizeof(dir));
            for (i = 0; i < dir.lfd_nfiles; i++) {
                if (loption) {
                    fprintf(stdout, "%6d  %s\n", dir.lfd_files[i].ld_size,
                        dir.lfd_files[i].ld_name);
                } else {
                        fprintf(stdout, "        %s\n",
                        dir.lfd_files[i].ld_name);
                }
            }

        /* Handle remote file system */

        } else if (dev == RFILESYS) {

            fd = open(RFILESYS, nbuf, "r");
            if (fd < 0){
                fprintf(stderr, "Cnanot open remote file %s\n", nbuf);
                return 1;
            }
            retval = read(fd, buf, 512);
            while (retval > 0) {
                fprintf(stdout, "        %s\n",buf);
                retval = read(fd, buf, 512);
            }
            close(fd);
            return 0;

        } else {

            /* Handle erro case for unknown file system */

            fprintf(stderr, "%s: file system is an unknown type\n",
                args[0]);
                return 1;
        }
        return 0;
}