/*
 * This file is part of the Nice GLib ICE library.
 *
 * (C) 2006-2008 Collabora Ltd.
 *  Contact: Dafydd Harries
 * (C) 2006-2008 Nokia Corporation. All rights reserved.
 *  Contact: Kai Vehmanen
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is the Nice GLib ICE library.
 *
 * The Initial Developers of the Original Code are Collabora Ltd and Nokia
 * Corporation. All Rights Reserved.
 *
 * Contributors:
 *   Dafydd Harries, Collabora Ltd.
 *   Youness Alaoui, Collabora Ltd.
 *   Kai Vehmanen, Nokia
 *
 * Alternatively, the contents of this file may be used under the terms of the
 * the GNU Lesser General Public License Version 2.1 (the "LGPL"), in which
 * case the provisions of LGPL are applicable instead of those above. If you
 * wish to allow use of your version of this file only under the terms of the
 * LGPL and not to allow others to use your version of this file under the
 * MPL, indicate your decision by deleting the provisions above and replace
 * them with the notice and other provisions required by the LGPL. If you do
 * not delete the provisions above, a recipient may use your version of this
 * file under either the MPL or the LGPL.
 */
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <string.h>

#include "random.h"
#include "random-glib.h"

static NiceRNG * (*nice_rng_new_func) (void) = NULL;

/* 
 * Creates a new random number generator instance.
 */
NiceRNG *
nice_rng_new (void)
{
  if (nice_rng_new_func == NULL)
    return nice_rng_glib_new ();
  else
    return nice_rng_new_func ();
}

/*
 * Sets a new generator function.
 */
void
nice_rng_set_new_func (NiceRNG * (*func) (void))
{
  nice_rng_new_func = func;
}

/*
 * Frees the random number generator instance.
 *
 * @param rng context
 */
void
nice_rng_free (NiceRNG *rng)
{
  rng->free (rng);
}

/*
 * Generates random octets.
 *
 * @param rng context
 * @param len number of octets to product
 * @param buf buffer to store the results
 */
void
nice_rng_generate_bytes (NiceRNG *rng, guint len, gchar *buf)
{
  rng->generate_bytes (rng, len, buf);
}

/*
 * Generates a random unsigned integer.
 * 
 * @param rng context
 * @param low closed lower bound
 * @param high open upper bound
 */
guint
nice_rng_generate_int (NiceRNG *rng, guint low, guint high)
{
  return rng->generate_int (rng, low, high);
}

/*
 * Generates a stream of octets containing only characters
 * with ASCII codecs of 0x41-5A (A-Z), 0x61-7A (a-z), 
 * 0x30-39 (0-9), 0x2b (+) and 0x2f (/). This matches 
 * the definition of 'ice-char' in ICE Ispecification,
 * section 15.1 (ID-16).
 *
 * @param rng context
 * @param len number of octets to product
 * @param buf buffer to store the results
 */
void
nice_rng_generate_bytes_print (NiceRNG *rng, guint len, gchar *buf)
{
  guint i;
  const gchar *chars =
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "abcdefghijklmnopqrstuvwxyz"
    "0123456789"
    "+/";

  for (i = 0; i < len; i++)
    buf[i] = chars[nice_rng_generate_int (rng, 0, strlen (chars))];
}