Purism-Calls/plugins/sip/calls-sip-origin.c

/*
 * Copyright (C) 2021 Purism SPC
 *
 * This file is part of Calls.
 *
 * Calls 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 3 of the License, or
 * (at your option) any later version.
 *
 * Calls 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 Calls.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Author: Evangelos Ribeiro Tzaras <evangelos.tzaras@puri.sm>
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 */

#include "calls-sip-origin.h"

#include "calls-message-source.h"
#include "calls-origin.h"
#include "calls-sip-call.h"
#include "calls-sip-util.h"
#include "calls-sip-enums.h"
#include "calls-sip-media-manager.h"

#include <glib/gi18n.h>
#include <glib-object.h>
#include <sofia-sip/nua.h>
#include <sofia-sip/su_tag.h>
#include <sofia-sip/su_tag_io.h>
#include <sofia-sip/sip_util.h>
#include <sofia-sip/sdp.h>


struct _CallsSipOrigin
{
  GObject parent_instance;
  GString *name;

  CallsSipContext *ctx;
  nua_t *nua;
  CallsSipHandles *oper;
  /* Maybe it makes sense to have one call handle (nua_handle_t) in
   * CallsSipCall (do we need a backpointer to CallsSipOrigin?)
   * and define the HMAGIC as a CallsSipOrigin
   */

  /* Direct connection mode is useful for debugging purposes */
  gboolean use_direct_connection;

  /* Needed to handle shutdown correctly. See sip_callback and dispose method */
  gboolean is_nua_shutdown;

  SipAccountState state;

  CallsSipMediaManager *media_manager;

  /* Account information */
  gchar *user;
  gchar *password;
  gchar *host;
  gchar *transport_protocol;
  const gchar *protocol_prefix;
  gint port;

  GList *calls;
  GHashTable *call_handles;
};

static void calls_sip_origin_message_source_interface_init (CallsOriginInterface *iface);
static void calls_sip_origin_origin_interface_init (CallsOriginInterface *iface);

G_DEFINE_TYPE_WITH_CODE (CallsSipOrigin, calls_sip_origin, G_TYPE_OBJECT,
                         G_IMPLEMENT_INTERFACE (CALLS_TYPE_MESSAGE_SOURCE,
                                                calls_sip_origin_message_source_interface_init)
                         G_IMPLEMENT_INTERFACE (CALLS_TYPE_ORIGIN,
                                                calls_sip_origin_origin_interface_init))

enum {
  PROP_0,
  PROP_NAME,
  PROP_ACC_USER,
  PROP_ACC_PASSWORD,
  PROP_ACC_HOST,
  PROP_ACC_PORT,
  PROP_ACC_PROTOCOL,
  PROP_ACC_DIRECT,
  PROP_SIP_CONTEXT,
  PROP_ACC_STATE,
  PROP_CALLS,
  PROP_LAST_PROP,
};
static GParamSpec *props[PROP_LAST_PROP];


static void
sip_authenticate (CallsSipOrigin *origin,
                  nua_handle_t   *nh,
                  sip_t const    *sip)
{
  const gchar *scheme = NULL;
  const gchar *realm = NULL;
  g_autofree gchar *auth = NULL;
  sip_www_authenticate_t *www_auth = sip->sip_www_authenticate;
  sip_proxy_authenticate_t *proxy_auth = sip->sip_proxy_authenticate;

  if (www_auth) {
    scheme = www_auth->au_scheme;
    realm = msg_params_find (www_auth->au_params, "realm=");
  }
  else if (proxy_auth) {
    scheme = proxy_auth->au_scheme;
    realm = msg_params_find (proxy_auth->au_params, "realm=");
  }
  g_debug ("need to authenticate to realm %s", realm);

  auth = g_strdup_printf ("%s:%s:%s:%s",
                          scheme, realm, origin->user, origin->password);
  nua_authenticate (nh, NUTAG_AUTH (auth));
}


static void
sip_r_invite (int              status,
              char const      *phrase,
              nua_t           *nua,
              CallsSipOrigin  *origin,
              nua_handle_t    *nh,
              CallsSipHandles *op,
              sip_t const     *sip,
              tagi_t           tags[])
{
    g_debug ("response to outgoing INVITE: %03d %s", status, phrase);

    /* TODO call states (see i_state) */
    if (status == 401) {
      sip_authenticate (origin, nh, sip);
    }
    else if (status == 403) {
      g_warning ("wrong credentials?");
    }
    else if (status == 407) {
      sip_authenticate (origin, nh, sip);
    }
    else if (status == 904) {
      g_warning ("unmatched challenge");
    }
    else if (status == 180) {
    }
    else if (status == 100) {
    }
    else if (status == 200) {
    }
}


static void
sip_r_register (int              status,
                char const      *phrase,
                nua_t           *nua,
                CallsSipOrigin  *origin,
                nua_handle_t    *nh,
                CallsSipHandles *op,
                sip_t const     *sip,
                tagi_t           tags[])
{
  g_debug ("response to REGISTER: %03d %s", status, phrase);

  if (status == 200) {
    g_debug ("REGISTER successful");

    origin->state = SIP_ACCOUNT_ONLINE;
  }
  else if (status == 401) {
    sip_authenticate (origin, nh, sip);

    origin->state = SIP_ACCOUNT_AUTHENTICATING;
  }
  else if (status == 403) {
    g_warning ("wrong credentials?");
    origin->state = SIP_ACCOUNT_ERROR_RETRY;
  }
  else if (status == 904) {
    g_warning ("unmatched challenge");
    origin->state = SIP_ACCOUNT_ERROR_RETRY;
  }
  g_object_notify_by_pspec (G_OBJECT (origin), props[PROP_ACC_STATE]);
}


static void
sip_i_state (int              status,
             char const      *phrase,
             nua_t           *nua,
             CallsSipOrigin  *origin,
             nua_handle_t    *nh,
             CallsSipHandles *op,
             sip_t const     *sip,
             tagi_t           tags[])
{
  const sdp_session_t *r_sdp = NULL;
  gint call_state = nua_callstate_init;
  CallsCallState state;
  CallsSipCall *call;

  g_return_if_fail (CALLS_IS_SIP_ORIGIN (origin));

  call = g_hash_table_lookup (origin->call_handles, nh);

  g_return_if_fail (call != NULL);

  g_debug ("The call state has changed: %03d %s", status, phrase);
  tl_gets (tags,
           SOATAG_REMOTE_SDP_REF (r_sdp),
           NUTAG_CALLSTATE_REF (call_state),
           TAG_END ());

  /* XXX making some assumptions about the received SDP message here...
   * namely: that there is only the session wide connection c= line
   * and no individual connections per media stream.
   * also: rtcp port = rtp port + 1
   */
  if (r_sdp) {
    calls_sip_call_setup_remote_media (call,
                                       r_sdp->sdp_connection->c_address,
                                       r_sdp->sdp_media->m_port,
                                       r_sdp->sdp_media->m_port + 1);
  }

  /* TODO use CallCallStates with g_object_set (notify!) */
  switch (call_state) {
  case nua_callstate_init:
    return;

  case nua_callstate_calling:
    state = CALLS_CALL_STATE_DIALING;
    break;

  case nua_callstate_received:
    state = CALLS_CALL_STATE_INCOMING;
    break;

  case nua_callstate_ready:
    g_debug ("Call ready. Activating media pipeline");

    calls_sip_call_activate_media (call, TRUE);
    state = CALLS_CALL_STATE_ACTIVE;
    break;

  case nua_callstate_terminated:
    g_debug ("Call terminated. Deactivating media pipeline");

    calls_sip_call_activate_media (call, FALSE);
    state = CALLS_CALL_STATE_DISCONNECTED;
    break;

  case nua_callstate_authenticating:
    g_warning ("TODO Move authentication (INVITE) here");
    return;

  default:
    return;
  }

  calls_sip_call_set_state (call, state);
}


static void
sip_callback (nua_event_t   event,
              int           status,
              char const   *phrase,
              nua_t        *nua,
              nua_magic_t  *magic,
              nua_handle_t *nh,
              nua_hmagic_t *hmagic,
              sip_t const  *sip,
              tagi_t        tags[])
{
  CallsSipOrigin *origin = CALLS_SIP_ORIGIN (magic);
  CallsSipHandles *op = origin->oper;
  const char * from = NULL;

  switch (event) {
  case nua_i_invite:
    tl_gets (tags, SIPTAG_FROM_STR_REF (from), TAG_END ());

    g_debug ("incoming call INVITE: %03d %s from %s", status, phrase, from);

    /* reject if there already is a ongoing call */
    if (op->call_handle) {
      nua_respond (nh, 486, NULL, TAG_END ());
      g_debug ("Cannot handle more than one call. Rejecting");
    }
    else
      calls_sip_origin_create_inbound (origin, from, nh);

    break;

  case nua_r_invite:
    sip_r_invite (status,
                  phrase,
                  nua,
                  origin,
                  nh,
                  op,
                  sip,
                  tags);
    break;

  case nua_i_ack:
    g_debug ("incoming ACK: %03d %s", status, phrase);
    break;

  case nua_i_bye:
    g_debug ("incoming BYE: %03d %s", status, phrase);
    break;

  case nua_r_bye:
    g_debug ("response to BYE: %03d %s", status, phrase);
    break;

  case nua_r_register:
    sip_r_register (status,
                    phrase,
                    nua,
                    origin,
                    nh,
                    op,
                    sip,
                    tags);
    break;

  case nua_r_set_params:
    g_debug ("response to set_params: %03d %s", status, phrase);
    break;

  case nua_i_outbound:
    g_debug ("status of outbound engine has changed: %03d %s", status, phrase);
    break;

  case nua_i_state:
    sip_i_state (status,
                 phrase,
                 nua,
                 origin,
                 nh,
                 op,
                 sip,
                 tags);
    break;

  case nua_r_cancel:
    g_debug ("response to CANCEL: %03d %s", status, phrase);
    break;

  case nua_r_terminate:
    break;

  case nua_r_shutdown:
    /* see also deinit_sip () */
    g_debug ("response to nua_shutdown: %03d %s", status, phrase);
    if (status == 200)
      origin->is_nua_shutdown = TRUE;
    break;

    /* Deprecated events */
  case nua_i_active:
    break;
  case nua_i_terminated:
    break;

  default:
    /* unknown event -> print out error message */
    g_warning ("unknown event %d: %03d %s",
               event,
               status,
               phrase);
    g_warning ("printing tags");
    tl_print(stdout, "", tags);
    break;
  }
}


static nua_t *
setup_nua (CallsSipOrigin *self)
{
  g_autofree gchar *address = NULL;
  nua_t *nua;
  gboolean use_sips;

  g_return_val_if_fail (CALLS_IS_SIP_ORIGIN (self), NULL);

  address = g_strconcat (self->protocol_prefix, ":", self->user, "@", self->host, NULL);

  use_sips = check_sips (address);

  // TODO URLs must be changed to accomodate IPv6 use case (later, not important right now)
  // Note: This is why using hostname does not work! (do we need two nua contexts for ipv4 and ipv6?)
  nua = nua_create (self->ctx->root,
                    sip_callback,
                    self,
                    NUTAG_USER_AGENT ("sofia-test/0.0.1"),
                    NUTAG_URL ("sip:0.0.0.0:5060"),
                    TAG_IF (use_sips, NUTAG_SIPS_URL ("sips:0.0.0.0:5060")),
                    NUTAG_M_USERNAME (self->user),
                    SIPTAG_FROM_STR (address),
                    NUTAG_ENABLEINVITE (1),
                    NUTAG_AUTOANSWER (0),
                    NUTAG_AUTOACK (1),
                    NUTAG_MEDIA_ENABLE (1),
                    TAG_NULL ());

  return nua;
}


static CallsSipHandles *
setup_sip_handles (CallsSipOrigin *self)
{
  CallsSipHandles *oper;

  g_return_val_if_fail (CALLS_IS_SIP_ORIGIN (self), NULL);

  if (!(oper = su_zalloc (self->ctx->home, sizeof(CallsSipHandles)))) {
    g_warning ("cannot create handle");
    return NULL;
  }

  oper->context = self->ctx;
  oper->register_handle = nua_handle (self->nua, self->oper,
                                      NUTAG_REGISTRAR (self->host),
                                      TAG_END ());
  oper->call_handle = NULL;

  return oper;
}


static void
setup_account_for_direct_connection (CallsSipOrigin *self)
{
  g_return_if_fail (CALLS_IS_SIP_ORIGIN (self));

  /* honour username, if previously set */
  if (self->user == NULL)
    self->user = g_strdup (g_get_user_name ());

  g_free (self->host);
  self->host = g_strdup (g_get_host_name ());

  g_free (self->password);
  self->password = NULL;

  g_free (self->transport_protocol);
  self->transport_protocol = g_strdup ("UDP");

  self->protocol_prefix = get_protocol_prefix (self->transport_protocol);

  g_debug ("Notifying account changed:\n"
           "user: %s\nhost URL: %s", self->user, self->host);

  g_object_notify_by_pspec (G_OBJECT (self), props[PROP_ACC_USER]);
  g_object_notify_by_pspec (G_OBJECT (self), props[PROP_ACC_HOST]);
}


static gboolean
is_account_complete (CallsSipOrigin *self)
{
  g_return_val_if_fail (CALLS_IS_SIP_ORIGIN (self), FALSE);

  /* we need only need to check for password if needing to authenticate over a proxy/UAS */
  if (self->user == NULL ||
      (!self->use_direct_connection && self->password == NULL) ||
      self->host == NULL ||
      self->transport_protocol == NULL ||
      self->protocol_prefix == NULL)
    return FALSE;

  return TRUE;
}


static gboolean
init_sip_account (CallsSipOrigin *self,
                  GError        **error)
{
  gboolean recoverable = FALSE;

  g_return_val_if_fail (CALLS_IS_SIP_ORIGIN (self), FALSE);

  if (self->use_direct_connection && !is_account_complete (self)) {
    g_debug ("Account not set yet. Using user and hostname");
    setup_account_for_direct_connection (self);
  }

  if (!is_account_complete (self)) {
    g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
                 "Must have completed account setup before calling"
                 "init_sip_account ()"
                 "Try again when account is setup");
    recoverable = TRUE;
    goto err;
  }

  // setup_nua and setup_oper only after account data has been set
  self->nua = setup_nua (self);
  if (self->nua == NULL) {
    g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
                 "Failed setting up nua context");
    goto err;
  }

  self->oper = setup_sip_handles (self);
  if (self->oper == NULL) {
    g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
                 "Failed setting operation handles");
    goto err;
  }

  /* In the case of a direct connection we're immediately good to go */
  if (self->use_direct_connection)
    self->state = SIP_ACCOUNT_ONLINE;
  else
    self->state = SIP_ACCOUNT_OFFLINE;

  g_object_notify_by_pspec (G_OBJECT (self), props[PROP_ACC_STATE]);
  return TRUE;

 err:
  self->state = recoverable ? SIP_ACCOUNT_ERROR_RETRY : SIP_ACCOUNT_ERROR;
  g_object_notify_by_pspec (G_OBJECT (self), props[PROP_ACC_STATE]);
  return FALSE;
}


static void
remove_call (CallsSipOrigin *self,
             CallsCall      *call,
             const gchar    *reason)
{
  CallsOrigin *origin;
  CallsSipCall *sip_call;
  gboolean inbound;
  nua_handle_t *nh;

  origin = CALLS_ORIGIN (self);
  sip_call = CALLS_SIP_CALL (call);

  self->calls = g_list_remove (self->calls, call);

  g_object_get (sip_call,
                "inbound", &inbound,
                "nua-handle", &nh,
                NULL);

  /* TODO support multiple simultaneous calls */
  if (self->oper->call_handle == nh)
    self->oper->call_handle = NULL;

  g_hash_table_remove (self->call_handles, nh);
  nua_handle_unref (nh);

  g_signal_emit_by_name (origin, "call-removed", call, reason);

  g_object_unref (G_OBJECT (call));
}


static void
remove_calls (CallsSipOrigin *self,
              const gchar    *reason)
{
  CallsCall *call;
  GList *next;

  while (self->calls != NULL) {
    call = self->calls->data;
    next = self->calls->next;

    calls_call_hang_up (call);

    g_list_free_1 (self->calls);
    self->calls = next;

    g_signal_emit_by_name (self, "call-removed", call, reason);
    g_object_unref (call);
  }

  g_hash_table_remove_all (self->call_handles);

  g_clear_pointer (&self->oper->call_handle, nua_handle_unref);
}


static void
on_call_state_changed_cb (CallsSipOrigin *self,
                          CallsCallState  new_state,
                          CallsCallState  old_state,
                          CallsCall      *call)
{
  if (new_state != CALLS_CALL_STATE_DISCONNECTED)
    {
      return;
    }

  g_assert (CALLS_IS_SIP_ORIGIN (self));
  g_assert (CALLS_IS_CALL (call));

  remove_call (self, call, "Disconnected");
}


static void
add_call (CallsSipOrigin *self,
          const gchar    *address,
          gboolean        inbound,
          nua_handle_t   *handle)
{
  CallsSipCall *sip_call;
  CallsCall *call;
  g_autofree gchar *local_sdp = NULL;

  sip_call = calls_sip_call_new (address, inbound, handle);
  g_assert (sip_call != NULL);

  /* XXX dynamically get/probe free ports */
  calls_sip_call_setup_local_media (sip_call, 19042, 19043);

  local_sdp = calls_sip_media_manager_static_capabilities (self->media_manager,
                                                           19042,
                                                           check_sips (address));

  g_assert (local_sdp);
  g_debug ("Setting local SDP to string:\n%s", local_sdp);

  nua_set_params (self->nua,
                  SOATAG_USER_SDP_STR (local_sdp),
                  SOATAG_AF (SOA_AF_IP4_IP6),
                  TAG_END ());

  if (self->oper->call_handle)
    nua_handle_unref (self->oper->call_handle);

  self->oper->call_handle = handle;

  g_hash_table_insert (self->call_handles, handle, sip_call);

  if (!inbound)
    nua_invite (self->oper->call_handle,
                SIPTAG_TO_STR (address),
                SOATAG_RTP_SORT (SOA_RTP_SORT_REMOTE),
                SOATAG_RTP_SELECT (SOA_RTP_SELECT_ALL),
                TAG_END ());

  call = CALLS_CALL (sip_call);
  g_signal_connect_swapped (call, "state-changed",
                            G_CALLBACK (on_call_state_changed_cb),
                            self);

  self->calls = g_list_append (self->calls, sip_call);

  g_signal_emit_by_name (CALLS_ORIGIN (self), "call-added", call);
}


static void
dial (CallsOrigin *origin,
      const gchar *address)
{
  CallsSipOrigin *self;
  nua_handle_t *nh;
  g_assert (CALLS_ORIGIN (origin));
  g_assert (CALLS_IS_SIP_ORIGIN (origin));

  if (address == NULL) {
    g_warning ("Tried dialing on origin '%s' without an address",
               calls_origin_get_name (origin));
    return;
  }

  self = CALLS_SIP_ORIGIN (origin);

  nh = nua_handle (self->nua, self->oper,
                   NUTAG_MEDIA_ENABLE (1),
                   SOATAG_ACTIVE_AUDIO (SOA_ACTIVE_SENDRECV),
                   TAG_END ());

  g_debug ("Calling `%s'", address);

  add_call (CALLS_SIP_ORIGIN (origin), address, FALSE, nh);
}


static void
calls_sip_origin_set_property (GObject      *object,
                               guint         property_id,
                               const GValue *value,
                               GParamSpec   *pspec)
{
  CallsSipOrigin *self = CALLS_SIP_ORIGIN (object);

  switch (property_id) {

  case PROP_ACC_USER:
    g_free (self->user);
    self->user = g_value_dup_string (value);
    break;

  case PROP_ACC_PASSWORD:
    g_free (self->password);
    self->password = g_value_dup_string (value);
    break;

  case PROP_ACC_HOST:
    g_free (self->host);
    self->host = g_value_dup_string (value);
    break;

  case PROP_ACC_PORT:
    self->port = g_value_get_int (value);
    break;

  case PROP_ACC_PROTOCOL:
    if (!protocol_is_valid (g_value_get_string (value))) {
      g_warning ("Tried setting invalid protocol: '%s'\n"
                 "Continue using old protocol: '%s'",
                 g_value_get_string (value), self->transport_protocol);
      return;
    }

    g_free (self->transport_protocol);
    self->transport_protocol = g_value_dup_string (value);
    self->protocol_prefix = get_protocol_prefix (self->transport_protocol);
    break;

  case PROP_ACC_DIRECT:
    self->use_direct_connection = g_value_get_boolean (value);
    break;

  case PROP_SIP_CONTEXT:
    self->ctx = g_value_get_pointer (value);
    break;

  case PROP_ACC_STATE:
    g_warning ("Setting the account state does not yet have any effect");
    break;

  default:
    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
    break;
  }
}


static void
calls_sip_origin_get_property (GObject      *object,
                               guint         property_id,
                               GValue       *value,
                               GParamSpec   *pspec)
{
  CallsSipOrigin *self = CALLS_SIP_ORIGIN (object);

  switch (property_id) {
  case PROP_NAME:
    g_value_set_string (value, self->name->str);
    break;

  case PROP_CALLS:
    g_value_set_pointer (value, g_list_copy (self->calls));
    break;

  case PROP_ACC_USER:
    g_value_set_string (value, self->user);
    break;

  case PROP_ACC_HOST:
    g_value_set_string (value, self->host);
    break;

  case PROP_ACC_PORT:
    g_value_set_int (value, self->port);
    break;

  case PROP_ACC_PROTOCOL:
    g_value_set_string (value, self->transport_protocol);
    break;

  case PROP_ACC_STATE:
    g_value_set_enum (value, self->state);
    break;

  default:
    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
    break;
  }
}


static void
calls_sip_origin_constructed (GObject *object)
{
  CallsSipOrigin *self = CALLS_SIP_ORIGIN (object);
  g_autoptr (GError) error = NULL;

  if (!init_sip_account (self, &error)) {
    g_warning ("Error initializing the SIP account: %s", error->message);
  }

  self->media_manager = calls_sip_media_manager_default ();

  G_OBJECT_CLASS (calls_sip_origin_parent_class)->constructed (object);
}


static void
calls_sip_origin_dispose (GObject *object)
{
  CallsSipOrigin *self = CALLS_SIP_ORIGIN (object);

  if (self->state == SIP_ACCOUNT_NULL)
    return;

  remove_calls (self, NULL);

  if (self->oper) {
    g_clear_pointer (&self->oper->call_handle, nua_handle_unref);
    g_clear_pointer (&self->oper->register_handle, nua_handle_unref);
  }

  if (self->nua) {
    g_debug ("Requesting nua_shutdown ()");
    nua_shutdown (self->nua);
    // need to wait for nua_r_shutdown event before calling nua_destroy ()
    while (!self->is_nua_shutdown)
      su_root_step (self->ctx->root, 100);

    g_debug ("nua_shutdown () complete. Destroying nua handle");
    nua_destroy (self->nua);
    self->nua = NULL;
  }

  self->state = SIP_ACCOUNT_NULL;

  G_OBJECT_CLASS (calls_sip_origin_parent_class)->dispose (object);
}


static void
calls_sip_origin_finalize (GObject *object)
{
  CallsSipOrigin *self = CALLS_SIP_ORIGIN (object);

  g_string_free (self->name, TRUE);
  g_free (self->user);
  g_free (self->password);
  g_free (self->host);
  g_free (self->transport_protocol);
  g_hash_table_destroy (self->call_handles);

  G_OBJECT_CLASS (calls_sip_origin_parent_class)->finalize (object);
}


static void
calls_sip_origin_class_init (CallsSipOriginClass *klass)
{
  GObjectClass *object_class = G_OBJECT_CLASS (klass);

  object_class->constructed = calls_sip_origin_constructed;
  object_class->dispose = calls_sip_origin_dispose;
  object_class->finalize = calls_sip_origin_finalize;
  object_class->get_property = calls_sip_origin_get_property;
  object_class->set_property = calls_sip_origin_set_property;

  props[PROP_ACC_USER] =
    g_param_spec_string ("user",
                         "User",
                         "The username for authentication",
                         "",
                         G_PARAM_READWRITE | G_PARAM_CONSTRUCT);
  g_object_class_install_property (object_class, PROP_ACC_USER, props[PROP_ACC_USER]);

  props[PROP_ACC_PASSWORD] =
    g_param_spec_string ("password",
                         "Password",
                         "The password for authentication",
                         "",
                         G_PARAM_WRITABLE | G_PARAM_CONSTRUCT);
  g_object_class_install_property (object_class, PROP_ACC_PASSWORD, props[PROP_ACC_PASSWORD]);

  props[PROP_ACC_HOST] =
    g_param_spec_string ("host",
                         "Host",
                         "The fqdn of the SIP server",
                         "",
                         G_PARAM_READWRITE | G_PARAM_CONSTRUCT);
  g_object_class_install_property (object_class, PROP_ACC_HOST, props[PROP_ACC_HOST]);

  props[PROP_ACC_PORT] =
    g_param_spec_int ("port",
                      "Port",
                      "Port of the SIP server",
                      1025, 65535, 5060,
                      G_PARAM_READWRITE | G_PARAM_CONSTRUCT);
  g_object_class_install_property (object_class, PROP_ACC_PORT, props[PROP_ACC_PORT]);

  props[PROP_ACC_PROTOCOL] =
    g_param_spec_string ("protocol",
                         "Protocol",
                         "The protocol used to connect to the SIP server",
                         "UDP",
                         G_PARAM_READWRITE | G_PARAM_CONSTRUCT);
  g_object_class_install_property (object_class, PROP_ACC_PROTOCOL, props[PROP_ACC_PROTOCOL]);
  props[PROP_ACC_DIRECT] =
    g_param_spec_boolean ("direct-connection",
                          "Direct connection",
                          "Whether to use a direct connection (no SIP server)",
                          FALSE,
                          G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY);
  g_object_class_install_property (object_class, PROP_ACC_DIRECT, props[PROP_ACC_DIRECT]);

  props[PROP_SIP_CONTEXT] =
    g_param_spec_pointer ("sip-context",
                          "SIP context",
                          "The SIP context (sofia) used for our sip handles",
                          G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY);
  g_object_class_install_property (object_class, PROP_SIP_CONTEXT, props[PROP_SIP_CONTEXT]);

  props[PROP_ACC_STATE] =
    g_param_spec_enum ("account-state",
                       "Account state",
                       "The state of the SIP account",
                       SIP_TYPE_ACCOUNT_STATE,
                       SIP_ACCOUNT_NULL,
                       G_PARAM_READWRITE);
  g_object_class_install_property (object_class, PROP_ACC_STATE, props[PROP_ACC_STATE]);

#define IMPLEMENTS(ID, NAME) \
  g_object_class_override_property (object_class, ID, NAME);    \
  props[ID] = g_object_class_find_property(object_class, NAME);

  IMPLEMENTS (PROP_NAME, "name");
  IMPLEMENTS (PROP_CALLS, "calls");

#undef IMPLEMENTS
}


static void
calls_sip_origin_message_source_interface_init (CallsOriginInterface *iface)
{
}


static void
calls_sip_origin_origin_interface_init (CallsOriginInterface *iface)
{
  iface->dial = dial;
}


static void
calls_sip_origin_init (CallsSipOrigin *self)
{
  self->name = g_string_new (NULL);

  self->call_handles = g_hash_table_new (NULL, NULL);

  /* Direct connection mode is useful for debugging purposes */
  self->use_direct_connection = TRUE;

}


void
calls_sip_origin_create_inbound (CallsSipOrigin *self,
                                 const gchar    *address,
                                 nua_handle_t   *handle)
{
  g_return_if_fail (address != NULL);
  g_return_if_fail (CALLS_IS_SIP_ORIGIN (self));

  /* TODO support multiple calls */
  if (self->oper->call_handle)
    nua_handle_unref (self->oper->call_handle);

  self->oper->call_handle = handle;

  add_call (self, address, TRUE, handle);
}


CallsSipOrigin *
calls_sip_origin_new (const gchar     *name,
                      CallsSipContext *sip_context,
                      const gchar     *user,
                      const gchar     *password,
                      const gchar     *host,
                      gint             port,
                      const gchar     *protocol,
                      gboolean         direct_connection)
{
  CallsSipOrigin *origin;

  g_return_val_if_fail (sip_context != NULL, NULL);

  origin = g_object_new (CALLS_TYPE_SIP_ORIGIN,
                         "sip-context", sip_context,
                         "user", user,
                         "password", password,
                         "host", host,
                         "port", port,
                         "protocol", protocol,
                         "direct-connection", direct_connection,
                         NULL);

  g_string_assign (origin->name, name);

  return origin;
}