/* fir-tools/src/fir2csv/999_main.c
 *
 *  Copyright: ©2014, Laurence Withers
 *  Author: Laurence Withers <l@lwithers.me.uk>
 *  License: GPLv3
 */



void
usage(void)
{
    fputs("Usage:\n\n"
        "    " APP_NAME " [options] coeff.txt\n\n"
        "Options:\n"
        " -h, --help            Display this screen.\n"
        " -V, --version         Display version number.\n"
        " -o, --output <path>   Output file (default: stdout).\n"
        " -n, --num <num>       Number of points (default: 1000).\n"
        " -t, --tabs            Use tabs rather than commas in output.\n"
    "", stdout);
}



const struct option options[] = {
    { "help", no_argument, 0, 'h' },
    { "version", no_argument, 0, 'V' },
    { "output", required_argument, 0, 'o' },
    { "num", required_argument, 0, 'n' },
    { "tabs", no_argument, 0, 't' },
    { 0, 0, 0, 0 }
};

const char* optstr = "hn:o:V";



int
main(int argc, char* argv[])
{
    char* output_fname = 0, * tmp_fname, * endp;
    FILE* fp;
    int num_points = 1000;
    struct fir_filter_t* fi;

    while(1) {
        switch(getopt_long(argc, argv, optstr, options, 0)) {
        case -1:
            goto opts_done;

        case '?':
            return 1;

        case 'h':
            usage();
            return 0;

        case 'V':
            fputs(APP_NAME " " VERSION "\n", stdout);
            return 0;

        case 'o':
            output_fname = optarg;
            break;

        case 'n':
            errno = 0;
            num_points = strtol(optarg, &endp, 0);
            if(errno || !endp || *endp || num_points < 2) {
                fputs(APP_NAME ": invalid number of points. Expecting integer "
                    "> 1.\n", stderr);
                return 1;
            }
            break;

        case 't':
            csv_sep = '\t';
            break;
        }
    }
  opts_done:
    if(optind != (argc - 1)) {
        usage();
        return 1;
    }

    fi = load_filter(argv[optind]);

    if(output_fname) {
        tmp_fname = malloc(strlen(output_fname) + 10);
        strcpy(tmp_fname, output_fname);
        strcat(tmp_fname, ".new");
        fp = fopen(tmp_fname, "w");
        if(!fp) {
            fprintf(stderr, APP_NAME ": error opening \"%s\" for output: %m.\n",
                tmp_fname);
            return 1;
        }
    } else {
        fp = stdout;
    }

    fir2csv(fi, num_points, fp);

    if(output_fname) {
        if(fflush(fp) || fsync(fileno(fp)) || rename(tmp_fname, output_fname)) {
            fprintf(stderr, APP_NAME ": error writing to \"%s\": %m.\n",
                output_fname);
            unlink(tmp_fname);
            return 1;
        }
    }

    return 0;
}



/* options for text editors
vim: expandtab:ts=4:sw=4
*/