/*
  The oSIP library implements the Session Initiation Protocol (SIP -rfc3261-)
  Copyright (C) 2001,2002,2003  Aymeric MOIZARD jack@atosc.org
  
  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.
  
  This library 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
  Lesser General Public License for more details.
  
  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <osip2/internal.h>
#include <osip2/osip.h>

#include "fsm.h"

int
__osip_ist_init (osip_ist_t ** ist, osip_t * osip, osip_message_t * invite)
{
  int i;

  OSIP_TRACE (osip_trace
              (__FILE__, __LINE__, OSIP_INFO2, NULL, "allocating IST context\n"));

  *ist = (osip_ist_t *) osip_malloc (sizeof (osip_ist_t));
  if (*ist == NULL)
    return -1;
  memset (*ist, 0, sizeof (osip_ist_t));
  /* for INVITE retransmissions */
  {
    osip_via_t *via;
    char *proto;

    i = osip_message_get_via (invite, 0, &via); /* get top via */
    if (i != 0)
      goto ii_error_1;
    proto = via_get_protocol (via);
    if (proto == NULL)
      goto ii_error_1;

    if (osip_strcasecmp (proto, "TCP") != 0
        && osip_strcasecmp (proto, "TLS") != 0
        && osip_strcasecmp (proto, "SCTP") != 0)
      {                         /* for other reliable protocol than TCP, the timer
                                   must be desactived by the external application */
        (*ist)->timer_g_length = DEFAULT_T1;
        (*ist)->timer_i_length = DEFAULT_T4;
        (*ist)->timer_g_start.tv_sec = -1;      /* not started */
        (*ist)->timer_i_start.tv_sec = -1;      /* not started */
    } else
      {                         /* reliable protocol is used: */
        (*ist)->timer_g_length = -1;    /* A is not ACTIVE */
        (*ist)->timer_i_length = 0;     /* MUST do the transition immediatly */
        (*ist)->timer_g_start.tv_sec = -1;      /* not started */
        (*ist)->timer_i_start.tv_sec = -1;      /* not started */
      }
  }

  (*ist)->timer_h_length = 64 * DEFAULT_T1;
  (*ist)->timer_h_start.tv_sec = -1;    /* not started */

  return 0;

ii_error_1:
  osip_free (*ist);
  return -1;
}

int
__osip_ist_free (osip_ist_t * ist)
{
  if (ist == NULL)
    return -1;
  OSIP_TRACE (osip_trace
              (__FILE__, __LINE__, OSIP_INFO2, NULL, "free ist ressource\n"));
  osip_free (ist);
  return 0;
}

osip_event_t *
__osip_ist_need_timer_g_event (osip_ist_t * ist, state_t state, int transactionid)
{
  struct timeval now;

  osip_gettimeofday (&now, NULL);

  if (ist == NULL)
    return NULL;
  if (state == IST_COMPLETED)
    {
      if (ist->timer_g_start.tv_sec == -1)
        return NULL;
      if (osip_timercmp (&now, &ist->timer_g_start, >))
        return __osip_event_new (TIMEOUT_G, transactionid);
    }
  return NULL;
}

osip_event_t *
__osip_ist_need_timer_h_event (osip_ist_t * ist, state_t state, int transactionid)
{
  struct timeval now;

  osip_gettimeofday (&now, NULL);

  if (ist == NULL)
    return NULL;
  if (state == IST_COMPLETED)
    {
      /* may need timer H */
      if (ist->timer_h_start.tv_sec == -1)
        return NULL;
      if (osip_timercmp (&now, &ist->timer_h_start, >))
        return __osip_event_new (TIMEOUT_H, transactionid);
    }
  return NULL;
}

osip_event_t *
__osip_ist_need_timer_i_event (osip_ist_t * ist, state_t state, int transactionid)
{
  struct timeval now;

  osip_gettimeofday (&now, NULL);

  if (ist == NULL)
    return NULL;
  if (state == IST_CONFIRMED)
    {
      /* may need timer I */
      if (ist->timer_i_start.tv_sec == -1)
        return NULL;
      if (osip_timercmp (&now, &ist->timer_i_start, >))
        return __osip_event_new (TIMEOUT_I, transactionid);
    }
  return NULL;
}