/*

 * register.c

 *

 * Copyrigth (C) 2010 Nicolas Cornu <nicolas.cornu@ensi-bourges.fr>

 *

 * 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 2 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, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307

 * USA

 */

#include <glib.h>

#include <mcabber/logprint.h>

#include <jingle/register.h>

#include <jingle/jingle.h>

typedef struct {

  gchar *xmlns;

  JingleAppFuncs *funcs;

  JingleTransportType transtype;

} AppHandlerEntry;

typedef struct {

  gchar *xmlns;

  JingleTransportFuncs *funcs;

  JingleTransportType transtype;

  JingleTransportPriority priority;

} TransportHandlerEntry;

static AppHandlerEntry *jingle_find_app(const gchar *xmlns);

static TransportHandlerEntry *jingle_find_transport(const gchar *xmlns);

GSList *jingle_app_handlers = NULL;

GSList *jingle_transport_handlers = NULL;

/**

 * Register a new supported application.

 * type is the type of transport the data shall be sent over.

 */

void jingle_register_app(const gchar *xmlns, JingleAppFuncs *funcs,

                         JingleTransportType type)

{

  if (!g_str_has_prefix(xmlns, NS_JINGLE_APP_PREFIX)) return;

  AppHandlerEntry *h = g_new(AppHandlerEntry, 1);

  h->xmlns       = g_strdup(xmlns);

  h->funcs       = funcs;

  h->transtype   = type;

  jingle_app_handlers = g_slist_append(jingle_app_handlers, h);

}

/**

 * Register a new supported transport.

 * type is the type of transport.

 */

void jingle_register_transport(const gchar *xmlns,

                               JingleTransportFuncs *funcs,

                               JingleTransportType type,

                               JingleTransportPriority prio)

{

  if (!g_str_has_prefix(xmlns, NS_JINGLE_TRANSPORT_PREFIX)) return;

  TransportHandlerEntry *h = g_new(TransportHandlerEntry, 1);

  h->xmlns     = g_strdup(xmlns);

  h->funcs     = funcs;

  h->transtype = type;

  h->priority  = prio;

  jingle_transport_handlers = g_slist_append(jingle_transport_handlers, h);

}

JingleAppFuncs *jingle_get_appfuncs(const gchar *xmlns)

{

  AppHandlerEntry *entry;

  return (entry = jingle_find_app(xmlns)) != NULL ? entry->funcs : NULL;

}

JingleTransportFuncs *jingle_get_transportfuncs(const gchar *xmlns)

{

  TransportHandlerEntry *entry;

  return (entry = jingle_find_transport(xmlns)) != NULL ? entry->funcs : NULL;

}

gint cmp_forbid(gconstpointer a, gconstpointer b)

{

  return g_strcmp0((const gchar *)a, (const gchar *)b);

}

/**

 * Determine which transport is better suited for a given app.

 */

const gchar *jingle_transport_for_app(const gchar *appxmlns,

                                               GSList **forbid)

{

  AppHandlerEntry *app = jingle_find_app(appxmlns);

  GSList *entry;

  TransportHandlerEntry *thistransport, *besttransport = NULL;

  JingleTransportPriority bestprio = 0;

  JingleTransportType requestedtype;

  if (app == NULL)

    return NULL;

  requestedtype = app->transtype;

  for (entry = jingle_transport_handlers; entry; entry = entry->next) {

    thistransport = (TransportHandlerEntry *) entry->data;

    // Look if it's forbidden

    if (forbid != NULL &&

        g_slist_find_custom(*forbid, thistransport->xmlns, cmp_forbid))

      continue;

    if (thistransport->transtype == requestedtype &&

        thistransport->priority > bestprio) {

      bestprio = thistransport->priority;

      besttransport = thistransport;

    }

  }

  if (forbid != NULL)

    *forbid = g_slist_append(*forbid, besttransport->xmlns);

  return besttransport != NULL ? besttransport->xmlns : NULL;

}

/**

 * This function should work with AppHandlerEntry and

 * TransportHandlerEntry as long as both start with xmlns.

 */

static gint jingle_entry_cmp(gconstpointer a, gconstpointer b)

{

  return g_strcmp0(((AppHandlerEntry *) a)->xmlns, (const gchar*) b);

}

static AppHandlerEntry *jingle_find_app(const gchar *xmlns)

{

  GSList *entry = g_slist_find_custom(jingle_app_handlers, xmlns,

                                      jingle_entry_cmp);

  return entry != NULL ? (AppHandlerEntry *) entry->data : NULL;

}

static TransportHandlerEntry *jingle_find_transport(const gchar *xmlns)

{

  GSList *entry = g_slist_find_custom(jingle_transport_handlers, xmlns,

                                      jingle_entry_cmp);

  return entry != NULL ? (TransportHandlerEntry *) entry->data : NULL;

}

static void jingle_free_app(AppHandlerEntry *entry)

{

  g_free(entry->xmlns);

  g_free(entry);

}

static void jingle_free_transport(TransportHandlerEntry *entry)

{

  g_free(entry->xmlns);

  g_free(entry);

}

void jingle_unregister_app(const gchar *xmlns)

{

  AppHandlerEntry *entry = jingle_find_app(xmlns);

  if (entry) {

    jingle_free_app(entry);

    jingle_app_handlers = g_slist_remove(jingle_app_handlers, entry);

  }

}

void jingle_unregister_transport(const gchar *xmlns)

{

  TransportHandlerEntry *entry = jingle_find_transport(xmlns);

  if (entry) {

    jingle_free_transport(entry);

  }

}