/*
  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"

osip_statemachine_t *nict_fsm;

osip_statemachine_t *
__nict_get_fsm ()
{
  return nict_fsm;
}

void
__nict_unload_fsm ()
{
  transition_t *transition;
  osip_statemachine_t *statemachine = __nict_get_fsm ();

  for (transition = statemachine->transitions; transition != NULL; transition = statemachine->transitions)
    {
      REMOVE_ELEMENT(statemachine->transitions, transition);
      osip_free (transition);
    }

  osip_free (statemachine->transitions);
  osip_free (statemachine);
}

void
__nict_load_fsm ()
{
  transition_t *transition;

  nict_fsm = (osip_statemachine_t *) osip_malloc (sizeof (osip_statemachine_t));
  nict_fsm->transitions = NULL;

  /* to avoid race conditions between timers and first request */
  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_PRE_TRYING;
  transition->type = SND_REQUEST;
  transition->method = (void (*)(void *, void *)) &nict_snd_request;
  ADD_ELEMENT (nict_fsm->transitions, transition);
  /*
     transition         = (transition_t *) osip_malloc(sizeof(transition_t));
     transition->state  = NICT_TRYING;
     transition->type   = SND_REQUEST;
     transition->method = (void(*)(void *,void *))&nict_snd_request;
     osip_list_add(nict_fsm->transitions,transition,-1);
   */
  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_TRYING;
  transition->type = TIMEOUT_F;
  transition->method = (void (*)(void *, void *)) &osip_nict_timeout_f_event;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_TRYING;
  transition->type = TIMEOUT_E;
  transition->method = (void (*)(void *, void *)) &osip_nict_timeout_e_event;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_TRYING;
  transition->type = RCV_STATUS_1XX;
  transition->method = (void (*)(void *, void *)) &nict_rcv_1xx;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_TRYING;
  transition->type = RCV_STATUS_2XX;
  transition->method = (void (*)(void *, void *)) &nict_rcv_23456xx;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_TRYING;
  transition->type = RCV_STATUS_3456XX;
  transition->method = (void (*)(void *, void *)) &nict_rcv_23456xx;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_PROCEEDING;
  transition->type = TIMEOUT_F;
  transition->method = (void (*)(void *, void *)) &osip_nict_timeout_f_event;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_PROCEEDING;
  transition->type = TIMEOUT_E;
  transition->method = (void (*)(void *, void *)) &osip_nict_timeout_e_event;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_PROCEEDING;
  transition->type = RCV_STATUS_1XX;
  transition->method = (void (*)(void *, void *)) &nict_rcv_1xx;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_PROCEEDING;
  transition->type = RCV_STATUS_2XX;
  transition->method = (void (*)(void *, void *)) &nict_rcv_23456xx;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_PROCEEDING;
  transition->type = RCV_STATUS_3456XX;
  transition->method = (void (*)(void *, void *)) &nict_rcv_23456xx;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  transition = (transition_t *) osip_malloc (sizeof (transition_t));
  transition->state = NICT_COMPLETED;
  transition->type = TIMEOUT_K;
  transition->method = (void (*)(void *, void *)) &osip_nict_timeout_k_event;
  ADD_ELEMENT (nict_fsm->transitions, transition);

  /* these ccan be used to announce retransmission of 2xx and 3456xx
     For the state machine, it is completely useless...
     transition         = (transition_t *) osip_malloc(sizeof(transition_t));
     transition->state  = NICT_COMPLETED;
     transition->type   = RCV_STATUS_2XX;
     transition->method = (void(*)(void *,void *))&nict_rcv_23456xx2;
     osip_list_add(nict_fsm->transitions,transition,-1);

     transition         = (transition_t *) osip_malloc(sizeof(transition_t));
     transition->state  = NICT_COMPLETED;
     transition->type   = RCV_STATUS_3456XX;
     transition->method = (void(*)(void *,void *))&nict_rcv_23456xx2;
     osip_list_add(nict_fsm->transitions,transition,-1);
   */

}

static void
nict_handle_transport_error (osip_transaction_t * nict, int err)
{
  __osip_transport_error_callback (OSIP_NICT_TRANSPORT_ERROR, nict, err);
  __osip_transaction_set_state (nict, NICT_TERMINATED);
  __osip_kill_transaction_callback (OSIP_NICT_KILL_TRANSACTION, nict);
  /* TODO: MUST BE DELETED NOW */
}

void
nict_snd_request (osip_transaction_t * nict, osip_event_t * evt)
{
  int i;
  osip_t *osip = (osip_t *) nict->config;

  /* Here we have ict->orig_request == NULL */
  nict->orig_request = evt->sip;

  i = osip->cb_send_message (nict, evt->sip, nict->nict_context->destination,
                             nict->nict_context->port, nict->out_socket);

  if (i == 0)
    {
      /* invoke the right callback! */
      if (MSG_IS_REGISTER (evt->sip))
        __osip_message_callback (OSIP_NICT_REGISTER_SENT, nict,
                                 nict->orig_request);
      else if (MSG_IS_BYE (evt->sip))
        __osip_message_callback (OSIP_NICT_BYE_SENT, nict, nict->orig_request);
      else if (MSG_IS_OPTIONS (evt->sip))
        __osip_message_callback (OSIP_NICT_OPTIONS_SENT, nict, nict->orig_request);
      else if (MSG_IS_INFO (evt->sip))
        __osip_message_callback (OSIP_NICT_INFO_SENT, nict, nict->orig_request);
      else if (MSG_IS_CANCEL (evt->sip))
        __osip_message_callback (OSIP_NICT_CANCEL_SENT, nict, nict->orig_request);
      else if (MSG_IS_NOTIFY (evt->sip))
        __osip_message_callback (OSIP_NICT_NOTIFY_SENT, nict, nict->orig_request);
      else if (MSG_IS_SUBSCRIBE (evt->sip))
        __osip_message_callback (OSIP_NICT_SUBSCRIBE_SENT, nict,
                                 nict->orig_request);
      else
        __osip_message_callback (OSIP_NICT_UNKNOWN_REQUEST_SENT, nict,
                                 nict->orig_request);

      if (nict->nict_context->timer_e_length > 0) {
        osip_gettimeofday (&nict->nict_context->timer_e_start, NULL);
        add_gettimeofday (&nict->nict_context->timer_e_start,
			  nict->nict_context->timer_e_length);
      }
      __osip_transaction_set_state (nict, NICT_TRYING);
  } else
    {
      nict_handle_transport_error (nict, i);
    }
}

void
osip_nict_timeout_e_event (osip_transaction_t * nict, osip_event_t * evt)
{
  osip_t *osip = (osip_t *) nict->config;
  int i;

  /* reset timer */
  if (nict->state == NICT_TRYING)
    {
      nict->nict_context->timer_e_length = nict->nict_context->timer_e_length * 2;
      if (nict->nict_context->timer_e_length > 4000)
        nict->nict_context->timer_e_length = 4000;
  } else                        /* in PROCEEDING STATE, TIMER is always 4000 */
    nict->nict_context->timer_e_length = 4000;

  osip_gettimeofday (&nict->nict_context->timer_e_start, NULL);
  add_gettimeofday (&nict->nict_context->timer_e_start,
                    nict->nict_context->timer_e_length);

  /* retransmit REQUEST */
  i = osip->cb_send_message (nict, nict->orig_request,
                             nict->nict_context->destination,
                             nict->nict_context->port, nict->out_socket);
  if (i != 0)
    {
      nict_handle_transport_error (nict, i);
      return;
    }
  __osip_message_callback (OSIP_NICT_REQUEST_SENT_AGAIN, nict, nict->orig_request);
}

void
osip_nict_timeout_f_event (osip_transaction_t * nict, osip_event_t * evt)
{
  nict->nict_context->timer_f_length = -1;
  nict->nict_context->timer_f_start.tv_sec = -1;

  __osip_message_callback (OSIP_NICT_STATUS_TIMEOUT, nict, evt->sip);
  __osip_transaction_set_state (nict, NICT_TERMINATED);
  __osip_kill_transaction_callback (OSIP_NICT_KILL_TRANSACTION, nict);
}

void
osip_nict_timeout_k_event (osip_transaction_t * nict, osip_event_t * evt)
{
  nict->nict_context->timer_k_length = -1;
  nict->nict_context->timer_k_start.tv_sec = -1;

  __osip_transaction_set_state (nict, NICT_TERMINATED);
  __osip_kill_transaction_callback (OSIP_NICT_KILL_TRANSACTION, nict);
}

void
nict_rcv_1xx (osip_transaction_t * nict, osip_event_t * evt)
{
  /* leave this answer to the core application */

  if (nict->last_response != NULL)
    {
      osip_message_free (nict->last_response);
    }
  nict->last_response = evt->sip;
  __osip_message_callback (OSIP_NICT_STATUS_1XX_RECEIVED, nict, evt->sip);
  __osip_transaction_set_state (nict, NICT_PROCEEDING);
}

void
nict_rcv_23456xx (osip_transaction_t * nict, osip_event_t * evt)
{
  /* leave this answer to the core application */

  if (nict->last_response != NULL)
    {
      osip_message_free (nict->last_response);
    }
  nict->last_response = evt->sip;

  if (EVT_IS_RCV_STATUS_2XX (evt))
    __osip_message_callback (OSIP_NICT_STATUS_2XX_RECEIVED, nict,
                             nict->last_response);
  else if (MSG_IS_STATUS_3XX (nict->last_response))
    __osip_message_callback (OSIP_NICT_STATUS_3XX_RECEIVED, nict,
                             nict->last_response);
  else if (MSG_IS_STATUS_4XX (nict->last_response))
    __osip_message_callback (OSIP_NICT_STATUS_4XX_RECEIVED, nict,
                             nict->last_response);
  else if (MSG_IS_STATUS_5XX (nict->last_response))
    __osip_message_callback (OSIP_NICT_STATUS_5XX_RECEIVED, nict,
                             nict->last_response);
  else
    __osip_message_callback (OSIP_NICT_STATUS_6XX_RECEIVED, nict,
                             nict->last_response);

  if (nict->state != NICT_COMPLETED)    /* reset timer K */
    {
      osip_gettimeofday (&nict->nict_context->timer_k_start, NULL);
      add_gettimeofday (&nict->nict_context->timer_k_start,
                        nict->nict_context->timer_k_length);
    }
  __osip_transaction_set_state (nict, NICT_COMPLETED);
}