/*
  The oSIP library implements the Session Initiation Protocol (SIP -rfc3261-)
  Copyright (C) 2001-2020 Aymeric MOIZARD amoizard@antisip.com

  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"

transition_t nist_transition[10] = {
    {NIST_PRE_TRYING, RCV_REQUEST, (void (*)(void *, void *)) & nist_rcv_request, &nist_transition[1], NULL},       {NIST_TRYING, SND_STATUS_1XX, (void (*)(void *, void *)) & nist_snd_1xx, &nist_transition[2], NULL},
    {NIST_TRYING, SND_STATUS_2XX, (void (*)(void *, void *)) & nist_snd_23456xx, &nist_transition[3], NULL},        {NIST_TRYING, SND_STATUS_3456XX, (void (*)(void *, void *)) & nist_snd_23456xx, &nist_transition[4], NULL},
    {NIST_PROCEEDING, SND_STATUS_1XX, (void (*)(void *, void *)) & nist_snd_1xx, &nist_transition[5], NULL},        {NIST_PROCEEDING, SND_STATUS_2XX, (void (*)(void *, void *)) & nist_snd_23456xx, &nist_transition[6], NULL},
    {NIST_PROCEEDING, SND_STATUS_3456XX, (void (*)(void *, void *)) & nist_snd_23456xx, &nist_transition[7], NULL}, {NIST_PROCEEDING, RCV_REQUEST, (void (*)(void *, void *)) & nist_rcv_request, &nist_transition[8], NULL},
    {NIST_COMPLETED, TIMEOUT_J, (void (*)(void *, void *)) & osip_nist_timeout_j_event, &nist_transition[9], NULL}, {NIST_COMPLETED, RCV_REQUEST, (void (*)(void *, void *)) & nist_rcv_request, NULL, NULL}};

osip_statemachine_t nist_fsm = {nist_transition};

static void nist_handle_transport_error(osip_transaction_t *nist, int err) {
  __osip_transport_error_callback(OSIP_NIST_TRANSPORT_ERROR, nist, err);
  __osip_transaction_set_state(nist, NIST_TERMINATED);
  __osip_kill_transaction_callback(OSIP_NIST_KILL_TRANSACTION, nist);
  /* TODO: MUST BE DELETED NOW */
}

void nist_rcv_request(osip_transaction_t *nist, osip_event_t *evt) {
  int i;

  if (nist->state == NIST_PRE_TRYING) { /* announce new REQUEST */
    /* Here we have ist->orig_request == NULL */
    nist->orig_request = evt->sip;

    if (MSG_IS_REGISTER(evt->sip))
      __osip_message_callback(OSIP_NIST_REGISTER_RECEIVED, nist, nist->orig_request);

    else if (MSG_IS_BYE(evt->sip))
      __osip_message_callback(OSIP_NIST_BYE_RECEIVED, nist, nist->orig_request);

    else if (MSG_IS_OPTIONS(evt->sip))
      __osip_message_callback(OSIP_NIST_OPTIONS_RECEIVED, nist, nist->orig_request);

    else if (MSG_IS_INFO(evt->sip))
      __osip_message_callback(OSIP_NIST_INFO_RECEIVED, nist, nist->orig_request);

    else if (MSG_IS_CANCEL(evt->sip))
      __osip_message_callback(OSIP_NIST_CANCEL_RECEIVED, nist, nist->orig_request);

    else if (MSG_IS_NOTIFY(evt->sip))
      __osip_message_callback(OSIP_NIST_NOTIFY_RECEIVED, nist, nist->orig_request);

    else if (MSG_IS_SUBSCRIBE(evt->sip))
      __osip_message_callback(OSIP_NIST_SUBSCRIBE_RECEIVED, nist, nist->orig_request);

    else
      __osip_message_callback(OSIP_NIST_UNKNOWN_REQUEST_RECEIVED, nist, nist->orig_request);

  } else { /* NIST_PROCEEDING or NIST_COMPLETED */

    /* delete retransmission */
    osip_message_free(evt->sip);

    __osip_message_callback(OSIP_NIST_REQUEST_RECEIVED_AGAIN, nist, nist->orig_request);

    if (nist->last_response != NULL) { /* retransmit last response */
      i = __osip_transaction_snd_xxx(nist, nist->last_response);

      if (i != 0) {
        nist_handle_transport_error(nist, i);
        return;

      } else {
        if (MSG_IS_STATUS_1XX(nist->last_response))
          __osip_message_callback(OSIP_NIST_STATUS_1XX_SENT, nist, nist->last_response);

        else if (MSG_IS_STATUS_2XX(nist->last_response))
          __osip_message_callback(OSIP_NIST_STATUS_2XX_SENT_AGAIN, nist, nist->last_response);

        else
          __osip_message_callback(OSIP_NIST_STATUS_3456XX_SENT_AGAIN, nist, nist->last_response);

        return;
      }
    }

    /* we are already in the proper state */
    return;
  }

  /* we come here only if it was the first REQUEST received */
  __osip_transaction_set_state(nist, NIST_TRYING);
}

void nist_snd_1xx(osip_transaction_t *nist, osip_event_t *evt) {
  int i;

  if (nist->last_response != NULL) {
    osip_message_free(nist->last_response);
  }

  nist->last_response = evt->sip;

  i = __osip_transaction_snd_xxx(nist, nist->last_response);

  if (i != 0) {
    nist_handle_transport_error(nist, i);
    return;

  } else
    __osip_message_callback(OSIP_NIST_STATUS_1XX_SENT, nist, nist->last_response);

  __osip_transaction_set_state(nist, NIST_PROCEEDING);
}

void nist_snd_23456xx(osip_transaction_t *nist, osip_event_t *evt) {
  int i;

  if (nist->last_response != NULL) {
    osip_message_free(nist->last_response);
  }

  nist->last_response = evt->sip;

  i = __osip_transaction_snd_xxx(nist, nist->last_response);

  if (i != 0) {
    nist_handle_transport_error(nist, i);
    return;

  } else {
    if (EVT_IS_SND_STATUS_2XX(evt))
      __osip_message_callback(OSIP_NIST_STATUS_2XX_SENT, nist, nist->last_response);

    else if (MSG_IS_STATUS_3XX(nist->last_response))
      __osip_message_callback(OSIP_NIST_STATUS_3XX_SENT, nist, nist->last_response);

    else if (MSG_IS_STATUS_4XX(nist->last_response))
      __osip_message_callback(OSIP_NIST_STATUS_4XX_SENT, nist, nist->last_response);

    else if (MSG_IS_STATUS_5XX(nist->last_response))
      __osip_message_callback(OSIP_NIST_STATUS_5XX_SENT, nist, nist->last_response);

    else
      __osip_message_callback(OSIP_NIST_STATUS_6XX_SENT, nist, nist->last_response);
  }

  if (nist->state != NIST_COMPLETED) { /* start J timer */
    osip_gettimeofday(&nist->nist_context->timer_j_start, NULL);
    add_gettimeofday(&nist->nist_context->timer_j_start, nist->nist_context->timer_j_length);
  }

  __osip_transaction_set_state(nist, NIST_COMPLETED);
}

void osip_nist_timeout_j_event(osip_transaction_t *nist, osip_event_t *evt) {
  nist->nist_context->timer_j_length = -1;
  nist->nist_context->timer_j_start.tv_sec = -1;

  __osip_transaction_set_state(nist, NIST_TERMINATED);
  __osip_kill_transaction_callback(OSIP_NIST_KILL_TRANSACTION, nist);
}