/* $Id$ */
/* 
 * Copyright (C) 2003-2006 Benny Prijono <benny@prijono.org>
 *
 * 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 "pjsua.h"
#include <pj/log.h>


/*
 * pjsua_inv.c
 *
 * Invite session specific functionalities.
 */

#define THIS_FILE   "pjsua_inv.c"


/**
 * Make outgoing call.
 */
pj_status_t pjsua_invite(const char *cstr_dest_uri,
			 pjsip_inv_session **p_inv)
{
    pj_str_t dest_uri;
    pjsip_dialog *dlg;
    pjmedia_sdp_session *offer;
    pjsip_inv_session *inv;
    struct pjsua_inv_data *inv_data;
    pjsip_tx_data *tdata;
    pj_status_t status;

    /* Convert cstr_dest_uri to dest_uri */
    
    dest_uri = pj_str((char*)cstr_dest_uri);

    /* Create outgoing dialog: */

    status = pjsip_dlg_create_uac( pjsip_ua_instance(), &pjsua.local_uri,
				   &pjsua.contact_uri, &dest_uri, &dest_uri,
				   &dlg);
    if (status != PJ_SUCCESS) {
	pjsua_perror("Dialog creation failed", status);
	return status;
    }

    /* Get media capability from media endpoint: */

    status = pjmedia_endpt_create_sdp( pjsua.med_endpt, dlg->pool,
				       1, &pjsua.med_skinfo, &offer);
    if (status != PJ_SUCCESS) {
	pjsua_perror("pjmedia unable to create SDP", status);
	goto on_error;
    }

    /* Create the INVITE session: */

    status = pjsip_inv_create_uac( dlg, offer, 0, &inv);
    if (status != PJ_SUCCESS) {
	pjsua_perror("Invite session creation failed", status);
	goto on_error;
    }


    /* Create and associate our data in the session. */

    inv_data = pj_pool_zalloc( dlg->pool, sizeof(struct pjsua_inv_data));
    inv_data->inv = inv;
    dlg->mod_data[pjsua.mod.id] = inv_data;


    /* Set dialog Route-Set: */

    if (!pj_list_empty(&pjsua.route_set))
	pjsip_dlg_set_route_set(dlg, &pjsua.route_set);


    /* Set credentials: */

    pjsip_auth_clt_set_credentials( &dlg->auth_sess, pjsua.cred_count, 
				    pjsua.cred_info);


    /* Create initial INVITE: */

    status = pjsip_inv_invite(inv, &tdata);
    if (status != PJ_SUCCESS) {
	pjsua_perror("Unable to create initial INVITE request", status);
	goto on_error;
    }


    /* Send initial INVITE: */

    status = pjsip_inv_send_msg(inv, tdata, NULL);
    if (status != PJ_SUCCESS) {
	pjsua_perror("Unable to send initial INVITE request", status);
	goto on_error;
    }

    /* Add invite session to the list. */
    
    pj_list_push_back(&pjsua.inv_list, inv_data);


    /* Done. */

    *p_inv = inv;

    return PJ_SUCCESS;


on_error:

    PJ_TODO(DESTROY_DIALOG_ON_FAIL);
    return status;
}


/**
 * Handle incoming INVITE request.
 */
pj_bool_t pjsua_inv_on_incoming(pjsip_rx_data *rdata)
{
    pjsip_dialog *dlg = pjsip_rdata_get_dlg(rdata);
    pjsip_transaction *tsx = pjsip_rdata_get_tsx(rdata);
    pjsip_msg *msg = rdata->msg_info.msg;

    /*
     * Handle incoming INVITE outside dialog.
     */
    if (dlg == NULL && tsx == NULL &&
	msg->line.req.method.id == PJSIP_INVITE_METHOD)
    {
	pj_status_t status;
	pjsip_tx_data *response = NULL;
	unsigned options = 0;

	/* Verify that we can handle the request. */
	status = pjsip_inv_verify_request(rdata, &options, NULL, NULL,
					  pjsua.endpt, &response);
	if (status != PJ_SUCCESS) {

	    /*
	     * No we can't handle the incoming INVITE request.
	     */

	    if (response) {
		pjsip_response_addr res_addr;

		pjsip_get_response_addr(response->pool, rdata, &res_addr);
		pjsip_endpt_send_response(pjsua.endpt, &res_addr, response, 
					  NULL, NULL);

	    } else {

		/* Respond with 500 (Internal Server Error) */
		pjsip_endpt_respond_stateless(pjsua.endpt, rdata, 500, NULL,
					      NULL, NULL);
	    }

	} else {
	    /*
	     * Yes we can handle the incoming INVITE request.
	     */
	    pjsip_inv_session *inv;
	    struct pjsua_inv_data *inv_data;
	    pjmedia_sdp_session *answer;


	    /* Get media capability from media endpoint: */

	    status = pjmedia_endpt_create_sdp( pjsua.med_endpt, rdata->tp_info.pool,
					       1, &pjsua.med_skinfo, &answer );
	    if (status != PJ_SUCCESS) {

		pjsip_endpt_respond_stateless(pjsua.endpt, rdata, 500, NULL,
					      NULL, NULL);
		return PJ_TRUE;
	    }

	    /* Create dialog: */

	    status = pjsip_dlg_create_uas( pjsip_ua_instance(), rdata,
					   &pjsua.contact_uri, &dlg);
	    if (status != PJ_SUCCESS)
		return PJ_TRUE;


	    /* Create invite session: */

	    status = pjsip_inv_create_uas( dlg, rdata, answer, 0, &inv);
	    if (status != PJ_SUCCESS) {

		status = pjsip_dlg_create_response( dlg, rdata, 500, NULL,
						    &response);
		if (status == PJ_SUCCESS)
		    status = pjsip_dlg_send_response(dlg, 
						     pjsip_rdata_get_tsx(rdata),
						     response);
		return PJ_TRUE;

	    }


	    /* Create and attach pjsua data to the dialog: */

	    inv_data = pj_pool_zalloc(dlg->pool, sizeof(struct pjsua_inv_data));
	    inv_data->inv = inv;
	    dlg->mod_data[pjsua.mod.id] = inv_data;

	    pj_list_push_back(&pjsua.inv_list, inv_data);


	    /* Answer with 100 (using the dialog, not invite): */

	    status = pjsip_dlg_create_response(dlg, rdata, 100, NULL, &response);
	    if (status == PJ_SUCCESS)
		status = pjsip_dlg_send_response(dlg, pjsip_rdata_get_tsx(rdata), response);
	}

	/* This INVITE request has been handled. */
	return PJ_TRUE;
    }

    return PJ_FALSE;
}


/*
 * This callback receives notification from invite session when the
 * session state has changed.
 */
void pjsua_inv_on_state_changed(pjsip_inv_session *inv, pjsip_event *e)
{

    /* Destroy media session when invite session is disconnected. */
    if (inv->state == PJSIP_INV_STATE_DISCONNECTED) {
	struct pjsua_inv_data *inv_data;

	inv_data = inv->dlg->mod_data[pjsua.mod.id];

	pj_assert(inv_data != NULL);

	if (inv_data && inv_data->session) {
	    pjmedia_session_destroy(inv_data->session);
	    inv_data->session = NULL;

	    PJ_LOG(3,(THIS_FILE,"Media session is destroyed"));
	}

	if (inv_data) {

	    pj_list_erase(inv_data);

	}
    }

    pjsua_ui_inv_on_state_changed(inv, e);
}


/*
 * This callback is called by invite session framework when UAC session
 * has forked.
 */
void pjsua_inv_on_new_session(pjsip_inv_session *inv, pjsip_event *e)
{
    PJ_UNUSED_ARG(inv);
    PJ_UNUSED_ARG(e);

    PJ_TODO(HANDLE_FORKED_DIALOG);
}


/*
 * Callback to be called when SDP offer/answer negotiation has just completed
 * in the session. This function will start/update media if negotiation
 * has succeeded.
 */
void pjsua_inv_on_media_update(pjsip_inv_session *inv, pj_status_t status)
{
    struct pjsua_inv_data *inv_data;
    const pjmedia_sdp_session *local_sdp;
    const pjmedia_sdp_session *remote_sdp;

    if (status != PJ_SUCCESS) {

	pjsua_perror("SDP negotiation has failed", status);
	return;

    }

    /* Destroy existing media session, if any. */

    inv_data = inv->dlg->mod_data[pjsua.mod.id];
    if (inv_data && inv_data->session) {
	pjmedia_session_destroy(inv_data->session);
	inv_data->session = NULL;
    }

    /* Get local and remote SDP */

    status = pjmedia_sdp_neg_get_active_local(inv->neg, &local_sdp);
    if (status != PJ_SUCCESS) {
	pjsua_perror("Unable to retrieve currently active local SDP", status);
	return;
    }


    status = pjmedia_sdp_neg_get_active_remote(inv->neg, &remote_sdp);
    if (status != PJ_SUCCESS) {
	pjsua_perror("Unable to retrieve currently active remote SDP", status);
	return;
    }


    /* Create new media session. 
     * The media session is active immediately.
     */

    if (!pjsua.null_audio) {

	status = pjmedia_session_create( pjsua.med_endpt, 1, &pjsua.med_skinfo,
					 local_sdp, remote_sdp, 
					 &inv_data->session );
	if (status != PJ_SUCCESS) {
	    pjsua_perror("Unable to create media session", status);
	    return;
	}

	PJ_LOG(3,(THIS_FILE,"Media has been started successfully"));
    }
}