/* example.c --- Example code showing how to use stringprep().
 * Copyright (C) 2002-2026 Simon Josefsson
 *
 * This file is part of GNU Libidn.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <locale.h>		/* setlocale() */
#include <stringprep.h>

/*
 * Compiling using libtool and pkg-config is recommended:
 *
 * $ libtool cc -o example example.c `pkg-config --cflags --libs libidn`
 * $ ./example
 * Input string encoded as `ISO-8859-1': ª
 * Before locale2utf8 (length 2): aa 0a
 * Before stringprep (length 3): c2 aa 0a
 * After stringprep (length 2): 61 0a
 * $
 *
 */

int
main (void)
{
  char buf[BUFSIZ];
  char *p;
  int rc;
  size_t i;

  setlocale (LC_ALL, "");

  printf ("Input string encoded as `%s': ", stringprep_locale_charset ());
  fflush (stdout);
  if (!fgets (buf, BUFSIZ, stdin))
    perror ("fgets");
  buf[strlen (buf) - 1] = '\0';

  printf ("Before locale2utf8 (length %ld): ", (long int) strlen (buf));
  for (i = 0; i < strlen (buf); i++)
    printf ("%02x ", (unsigned) buf[i] & 0xFF);
  printf ("\n");

  p = stringprep_locale_to_utf8 (buf);
  if (p)
    {
      size_t plen = strlen (p);
      if (plen >= BUFSIZ)
	plen = BUFSIZ - 1;
      memcpy (buf, p, plen);
      buf[plen] = '\0';
      free (p);
    }
  else
    printf ("Could not convert string to UTF-8, continuing anyway...\n");

  printf ("Before stringprep (length %ld): ", (long int) strlen (buf));
  for (i = 0; i < strlen (buf); i++)
    printf ("%02x ", (unsigned) buf[i] & 0xFF);
  printf ("\n");

  rc = stringprep (buf, BUFSIZ, 0, stringprep_nameprep);
  if (rc != STRINGPREP_OK)
    printf ("Stringprep failed (%d): %s\n", rc, stringprep_strerror (rc));
  else
    {
      printf ("After stringprep (length %ld): ", (long int) strlen (buf));
      for (i = 0; i < strlen (buf); i++)
	printf ("%02x ", (unsigned) buf[i] & 0xFF);
      printf ("\n");
    }

  return 0;
}
