/* Compare media descriptor */
PJ_DEF(pj_status_t) pjmedia_sdp_media_cmp( const pjmedia_sdp_media *sd1,
					   const pjmedia_sdp_media *sd2,
					   unsigned option)
{
    unsigned i;
    pj_status_t status;

    PJ_ASSERT_RETURN(sd1 && sd2 && option==0, PJ_EINVAL);

    PJ_UNUSED_ARG(option);

    /* Compare media type. */
    if (pj_strcmp(&sd1->desc.media, &sd2->desc.media) != 0)
	return PJMEDIA_SDP_EMEDIANOTEQUAL;

    /* Compare port number. */
    if (sd1->desc.port != sd2->desc.port)
	return PJMEDIA_SDP_EPORTNOTEQUAL;

    /* Compare port count. */
    if (sd1->desc.port_count != sd2->desc.port_count)
	return PJMEDIA_SDP_EPORTNOTEQUAL;

    /* Compare transports. */
    if (pj_strcmp(&sd1->desc.transport, &sd2->desc.transport) != 0)
	return PJMEDIA_SDP_ETPORTNOTEQUAL;

    /* For zeroed port media, stop comparing here */
    if (sd1->desc.port == 0)
	return PJ_SUCCESS;

    /* Compare number of formats. */
    if (sd1->desc.fmt_count != sd2->desc.fmt_count)
	return PJMEDIA_SDP_EFORMATNOTEQUAL;

    /* Compare formats, in order. */
    for (i=0; i<sd1->desc.fmt_count; ++i) {
	if (pj_strcmp(&sd1->desc.fmt[i], &sd2->desc.fmt[i]) != 0)
	    return PJMEDIA_SDP_EFORMATNOTEQUAL;
    }

    /* Compare connection line, if they exist. */
    if (sd1->conn) {
	if (!sd2->conn)
	    return PJMEDIA_SDP_EMEDIANOTEQUAL;
	status = compare_conn(sd1->conn, sd2->conn);
    } else {
	if (sd2->conn)
	    return PJMEDIA_SDP_EMEDIANOTEQUAL;
    }

    /* Compare attributes. */
    status = compare_attr(sd1->attr_count, sd1->attr, 
			  sd2->attr_count, sd2->attr);
    if (status != PJ_SUCCESS)
	return status;

    /* Looks equal */
    return PJ_SUCCESS;
}

/**
 * VoX Mobile :: negative SIP response handler
 */
int get_vox_error_info(pjsip_event *e)
{
    int cause = 0;
    const pj_str_t HDR = { "Error-Info", 10 };
    const pj_str_t BLOCKED_PSTN = { "PSTN not allowed", 16 };
    const pj_str_t BLOCKED_DESTINATION = { "Blocked destination", 19 };

    if (e->body.tsx_state.type == PJSIP_EVENT_RX_MSG) {

        pjsip_generic_string_hdr *hdr = (pjsip_generic_string_hdr*)pjsip_msg_find_hdr_by_name(
                                         e->body.tsx_state.src.rdata->msg_info.msg,
                                         &HDR,
                                         NULL);

        if (hdr) {
            if (pj_strcmp(&hdr->hvalue, &BLOCKED_PSTN) == 0)
                cause = 403;
            else if (pj_strcmp(&hdr->hvalue, &BLOCKED_DESTINATION) == 0)
                cause = 580;
            else {
                cause = (int)pj_strtoul(&hdr->hvalue);
            }
        }
    }

    return cause;
}

static pj_bool_t mod_stateless_on_rx_request(pjsip_rx_data *rdata)
{
    const pj_str_t stateless_user = { "0", 1 };
    pjsip_uri *uri;
    pjsip_sip_uri *sip_uri;

    uri = pjsip_uri_get_uri(rdata->msg_info.msg->line.req.uri);

    /* Only want to receive SIP/SIPS scheme */
    if (!PJSIP_URI_SCHEME_IS_SIP(uri) && !PJSIP_URI_SCHEME_IS_SIPS(uri))
	return PJ_FALSE;

    sip_uri = (pjsip_sip_uri*) uri;

    /* Check for matching user part */
    if (pj_strcmp(&sip_uri->user, &stateless_user)!=0)
	return PJ_FALSE;

    /*
     * Yes, this is for us.
     */

    /* Ignore ACK request */
    if (rdata->msg_info.msg->line.req.method.id == PJSIP_ACK_METHOD)
	return PJ_TRUE;

    /*
     * Respond statelessly with 200/OK.
     */
    pjsip_endpt_respond_stateless(app.sip_endpt, rdata, 200, NULL,
				  NULL, NULL);
    app.server.cur_state.stateless_cnt++;
    return PJ_TRUE;
}

static int pjsip_name_addr_compare(  pjsip_uri_context_e context,
                                     const pjsip_name_addr *naddr1,
                                     const pjsip_name_addr *naddr2)
{
    int d;

    /* Check that naddr2 is also a name_addr */
    if (naddr1->vptr != naddr2->vptr)
        return -1;

    /* I'm not sure whether display name is included in the comparison. */
    if (pj_strcmp(&naddr1->display, &naddr2->display) != 0) {
        return -1;
    }

    pj_assert( naddr1->uri != NULL );
    pj_assert( naddr2->uri != NULL );

    /* Compare name-addr as URL */
    d = pjsip_uri_cmp( context, naddr1->uri, naddr2->uri);
    if (d)
        return d;

    return 0;
}

PJ_DEF(unsigned) pjmedia_sdp_attr_remove_all(unsigned *count,
					     pjmedia_sdp_attr *attr_array[],
					     const char *name)
{
    unsigned i, removed = 0;
    pj_str_t attr_name;

    PJ_ASSERT_RETURN(count && attr_array && name, PJ_EINVAL);

    attr_name.ptr = (char*)name;
    attr_name.slen = pj_ansi_strlen(name);

    for (i=0; i<*count; ) {
	if (pj_strcmp(&attr_array[i]->name, &attr_name)==0) {
	    pj_array_erase(attr_array, sizeof(pjmedia_sdp_attr*),
			   *count, i);
	    --(*count);
	    ++removed;
	} else {
	    ++i;
	}   
    }

    return removed;
}

/* Set the published address of the transport */
static void udp_set_pub_name(struct udp_transport *tp,
			     const pjsip_host_port *a_name)
{
    enum { INFO_LEN = 80 };
    char local_addr[PJ_INET6_ADDRSTRLEN+10];
    char pub_addr[PJ_INET6_ADDRSTRLEN+10];

    pj_assert(a_name->host.slen != 0);
    
    if (pj_strcmp(&tp->base.local_name.host, &a_name->host) == 0 &&
        tp->base.local_name.port == a_name->port)
    {
        return;
    }
    
    pj_strdup_with_null(tp->base.pool, &tp->base.local_name.host, 
			&a_name->host);
    tp->base.local_name.port = a_name->port;

    /* Update transport info. */
    if (tp->base.info == NULL) {
	tp->base.info = (char*) pj_pool_alloc(tp->base.pool, INFO_LEN);
    }

    pj_sockaddr_print(&tp->base.local_addr, local_addr, sizeof(local_addr), 3);
    pj_addr_str_print(&tp->base.local_name.host, 
		      tp->base.local_name.port, 
		      pub_addr, sizeof(pub_addr), 1),

    pj_ansi_snprintf( tp->base.info, INFO_LEN, "udp %s [published as %s]",
		      local_addr, pub_addr);
}

/*! \brief Helper function which returns a UDP transport bound to the given address and port */
static pjsip_transport *multihomed_get_udp_transport(pj_str_t *address, int port)
{
	struct ao2_container *transports = ast_sorcery_retrieve_by_fields(ast_sip_get_sorcery(), "transport",
		AST_RETRIEVE_FLAG_MULTIPLE | AST_RETRIEVE_FLAG_ALL, NULL);
	struct ast_sip_transport *transport;
	struct ao2_iterator iter;
	pjsip_transport *sip_transport = NULL;

	if (!transports) {
		return NULL;
	}

	for (iter = ao2_iterator_init(transports, 0); (transport = ao2_iterator_next(&iter)); ao2_ref(transport, -1)) {
		if ((transport->type != AST_TRANSPORT_UDP) ||
			(pj_strcmp(&transport->state->transport->local_name.host, address)) ||
			(transport->state->transport->local_name.port != port)) {
			continue;
		}

		sip_transport = transport->state->transport;
		ao2_ref(transport, -1);
		break;
	}
	ao2_iterator_destroy(&iter);

	ao2_ref(transports, -1);

	return sip_transport;
}

pjmedia_sdp_attr_find (unsigned count, 
		       pjmedia_sdp_attr *const attr_array[],
		       const pj_str_t *name,
		       const pj_str_t *c_fmt)
{
    unsigned i;
    unsigned c_pt = 0xFFFF;

    if (c_fmt)
	c_pt = pj_strtoul(c_fmt);

    for (i=0; i<count; ++i) {
	if (pj_strcmp(&attr_array[i]->name, name) == 0) {
	    const pjmedia_sdp_attr *a = attr_array[i];
	    if (c_fmt) {
		unsigned pt = (unsigned) pj_strtoul2(&a->value, NULL, 10);
		if (pt == c_pt) {
		    return (pjmedia_sdp_attr*)a;
		}
	    } else 
		return (pjmedia_sdp_attr*)a;
	}
    }
    return NULL;
}

/* Compare connection line. */
static pj_status_t compare_conn(const pjmedia_sdp_conn *c1,
				const pjmedia_sdp_conn *c2)
{
    /* Compare network type. */
    if (pj_strcmp(&c1->net_type, &c2->net_type) != 0)
	return PJMEDIA_SDP_ECONNNOTEQUAL;

    /* Compare address type. */
    if (pj_strcmp(&c1->addr_type, &c2->addr_type) != 0)
	return PJMEDIA_SDP_ECONNNOTEQUAL;

    /* Compare address. */
    if (pj_strcmp(&c1->addr, &c2->addr) != 0)
	return PJMEDIA_SDP_ECONNNOTEQUAL;

    return PJ_SUCCESS;
}

PJ_DEF(int) pjsip_cred_info_cmp(const pjsip_cred_info *cred1,
				const pjsip_cred_info *cred2)
{
    int result;

    result = pj_strcmp(&cred1->realm, &cred2->realm);
    if (result) goto on_return;
    result = pj_strcmp(&cred1->scheme, &cred2->scheme);
    if (result) goto on_return;
    result = pj_strcmp(&cred1->username, &cred2->username);
    if (result) goto on_return;
    result = pj_strcmp(&cred1->data, &cred2->data);
    if (result) goto on_return;
    result = (cred1->data_type != cred2->data_type);
    if (result) goto on_return;

    if ((cred1->data_type & EXT_MASK) == PJSIP_CRED_DATA_EXT_AKA) {
	result = pj_strcmp(&cred1->ext.aka.k, &cred2->ext.aka.k);
	if (result) goto on_return;
	result = pj_strcmp(&cred1->ext.aka.op, &cred2->ext.aka.op);
	if (result) goto on_return;
	result = pj_strcmp(&cred1->ext.aka.amf, &cred2->ext.aka.amf);
	if (result) goto on_return;
    }

on_return:
    return result;
}

/* 
 * Find a dialog.
 */
PJ_DEF(pjsip_dialog*) pjsip_ua_find_dialog(const pj_str_t *call_id,
					   const pj_str_t *local_tag,
					   const pj_str_t *remote_tag,
					   pj_bool_t lock_dialog)
{
    struct dlg_set *dlg_set;
    pjsip_dialog *dlg;

    PJ_ASSERT_RETURN(call_id && local_tag && remote_tag, NULL);

    /* Lock user agent. */
    pj_mutex_lock(mod_ua.mutex);

    /* Lookup the dialog set. */
    dlg_set = (struct dlg_set*)
    	      pj_hash_get(mod_ua.dlg_table, local_tag->ptr, local_tag->slen,
			  NULL);
    if (dlg_set == NULL) {
	/* Not found */
	pj_mutex_unlock(mod_ua.mutex);
	return NULL;
    }

    /* Dialog set is found, now find the matching dialog based on the
     * remote tag.
     */
    dlg = dlg_set->dlg_list.next;
    while (dlg != (pjsip_dialog*)&dlg_set->dlg_list) {	
	if (pj_strcmp(&dlg->remote.info->tag, remote_tag) == 0)
	    break;
	dlg = dlg->next;
    }

    if (dlg == (pjsip_dialog*)&dlg_set->dlg_list) {
	/* Not found */
	pj_mutex_unlock(mod_ua.mutex);
	return NULL;
    }

    /* Dialog has been found. It SHOULD have the right Call-ID!! */
    PJ_ASSERT_ON_FAIL(pj_strcmp(&dlg->call_id->id, call_id)==0, 
			{pj_mutex_unlock(mod_ua.mutex); return NULL;});

/* Verify incoming Authorization/Proxy-Authorization header against the 
 * specified credential.
 */
static pj_status_t pjsip_auth_verify( const pjsip_authorization_hdr *hdr,
				      const pj_str_t *method,
				      const pjsip_cred_info *cred_info )
{
    if (pj_stricmp(&hdr->scheme, &pjsip_DIGEST_STR) == 0) {
	char digest_buf[PJSIP_MD5STRLEN];
	pj_str_t digest;
	const pjsip_digest_credential *dig = &hdr->credential.digest;

	/* Check that username and realm match. 
	 * These checks should have been performed before entering this
	 * function.
	 */
	PJ_ASSERT_RETURN(pj_strcmp(&dig->username, &cred_info->username) == 0,
			 PJ_EINVALIDOP);
	PJ_ASSERT_RETURN(pj_strcmp(&dig->realm, &cred_info->realm) == 0,
			 PJ_EINVALIDOP);

	/* Prepare for our digest calculation. */
	digest.ptr = digest_buf;
	digest.slen = PJSIP_MD5STRLEN;

	/* Create digest for comparison. */
	pjsip_auth_create_digest(&digest, 
				 &hdr->credential.digest.nonce,
				 &hdr->credential.digest.nc, 
				 &hdr->credential.digest.cnonce,
				 &hdr->credential.digest.qop,
				 &hdr->credential.digest.uri,
				 &cred_info->realm,
				 cred_info, 
				 method );

	/* Compare digest. */
	return (pj_stricmp(&digest, &hdr->credential.digest.response) == 0) ?
	       PJ_SUCCESS : PJSIP_EAUTHINVALIDDIGEST;

    } else {
	pj_assert(!"Unsupported authentication scheme");
	return PJSIP_EINVALIDAUTHSCHEME;
    }
}

static int find_transport_in_use(void *obj, void *arg, int flags)
{
	struct ast_sip_transport *transport = obj;
	pjsip_rx_data *rdata = arg;

	if ((transport->state->transport == rdata->tp_info.transport) ||
		(transport->state->factory && !pj_strcmp(&transport->state->factory->addr_name.host, &rdata->tp_info.transport->local_name.host) &&
			transport->state->factory->addr_name.port == rdata->tp_info.transport->local_name.port)) {
		return CMP_MATCH | CMP_STOP;
	}

	return 0;
}

/* Verify incoming Authorization/Proxy-Authorization header against existing
 * credentials. Will return TRUE if the authorization request matches any of
 * the credential.
 */
PJ_DEF(pj_bool_t) pjsip_auth_verify(const pjsip_authorization_hdr *hdr,
				    const pj_str_t *method,
				    const pjsip_cred_info *cred_info )
{
    if (pj_stricmp(&hdr->scheme, &pjsip_DIGEST_STR) == 0) {
	char digest_buf[MD5STRLEN];
	pj_str_t digest;
	const pjsip_digest_credential *dig = &hdr->credential.digest;

	/* Check that username match. */
	if (pj_strcmp(&dig->username, &cred_info->username) != 0)
	    return PJ_FALSE;

	/* Check that realm match. */
	if (pj_strcmp(&dig->realm, &cred_info->realm) != 0)
	    return PJ_FALSE;

	/* Prepare for our digest calculation. */
	digest.ptr = digest_buf;
	digest.slen = MD5STRLEN;

	/* Create digest for comparison. */
	create_digest(  &digest, 
			&hdr->credential.digest.nonce,
			&hdr->credential.digest.nc, 
			&hdr->credential.digest.cnonce,
			&hdr->credential.digest.qop,
			&hdr->credential.digest.uri,
			cred_info, 
			method );

	return pj_stricmp(&digest, &hdr->credential.digest.response) == 0;

    } else {
	pj_assert(0);
	return PJ_FALSE;
    }
}

/*
 * Apply direction attribute in session to all media.
 */
static void apply_media_direction(pjmedia_sdp_session *sdp)
{
    pjmedia_sdp_attr *dir_attr = NULL;
    unsigned i;

    const pj_str_t inactive = { "inactive", 8 };
    const pj_str_t sendonly = { "sendonly", 8 };
    const pj_str_t recvonly = { "recvonly", 8 };
    const pj_str_t sendrecv = { "sendrecv", 8 };

    /* Find direction attribute in session, don't need to find default 
     * direction "sendrecv".
     */
    for (i = 0; i < sdp->attr_count && !dir_attr; ++i) {
	if (!pj_strcmp(&sdp->attr[i]->name, &sendonly) ||
	    !pj_strcmp(&sdp->attr[i]->name, &recvonly) ||
	    !pj_strcmp(&sdp->attr[i]->name, &inactive)) 
	{
	    dir_attr = sdp->attr[i];
	}
    }

    /* Found the direction attribute */
    if (dir_attr) {
	/* Remove the direction attribute in session */
	pjmedia_sdp_attr_remove(&sdp->attr_count, sdp->attr, dir_attr);

	/* Apply the direction attribute to all media, but not overriding it
	 * if media already has direction attribute.
	 */
	for (i = 0; i < sdp->media_count; ++i) {
	    pjmedia_sdp_media *m;
	    unsigned j;

	    /* Find direction attribute in this media */
	    m = sdp->media[i];
	    for (j = 0; j < m->attr_count; ++j) {
		if (!pj_strcmp(&m->attr[j]->name, &sendrecv) ||
		    !pj_strcmp(&m->attr[j]->name, &sendonly) ||
		    !pj_strcmp(&m->attr[j]->name, &recvonly) ||
		    !pj_strcmp(&m->attr[j]->name, &inactive)) 
		{
		    break;
		}
	    }

	    /* Not found, apply direction attribute from session */
	    if (j == m->attr_count)
		pjmedia_sdp_media_add_attr(m, dir_attr);
	}
    }
}

/* Internal function to apply symmetric PT for the local answer. */
static void apply_answer_symmetric_pt(pj_pool_t *pool,
				      pjmedia_sdp_media *answer,
				      unsigned pt_cnt,
				      const pj_str_t pt_offer[],
				      const pj_str_t pt_answer[])
{
    pjmedia_sdp_attr *a_tmp[PJMEDIA_MAX_SDP_ATTR];
    unsigned i, a_tmp_cnt = 0;

    /* Rewrite the payload types in the answer if different to
     * the ones in the offer.
     */
    for (i = 0; i < pt_cnt; ++i) {
	pjmedia_sdp_attr *a;

	/* Skip if the PTs are the same already, e.g: static PT. */
	if (pj_strcmp(&pt_answer[i], &pt_offer[i]) == 0)
	    continue;

	/* Rewrite payload type in the answer to match to the offer */
	pj_strdup(pool, &answer->desc.fmt[i], &pt_offer[i]);

	/* Also update payload type in rtpmap */
	a = pjmedia_sdp_media_find_attr2(answer, "rtpmap", &pt_answer[i]);
	if (a) {
	    rewrite_pt(pool, &a->value, &pt_answer[i], &pt_offer[i]);
	    /* Temporarily remove the attribute in case the new payload
	     * type is being used by another format in the media.
	     */
	    pjmedia_sdp_media_remove_attr(answer, a);
	    a_tmp[a_tmp_cnt++] = a;
	}

	/* Also update payload type in fmtp */
	a = pjmedia_sdp_media_find_attr2(answer, "fmtp", &pt_answer[i]);
	if (a) {
	    rewrite_pt(pool, &a->value, &pt_answer[i], &pt_offer[i]);
	    /* Temporarily remove the attribute in case the new payload
	     * type is being used by another format in the media.
	     */
	    pjmedia_sdp_media_remove_attr(answer, a);
	    a_tmp[a_tmp_cnt++] = a;
	}
    }

    /* Return back 'rtpmap' and 'fmtp' attributes */
    for (i = 0; i < a_tmp_cnt; ++i)
	pjmedia_sdp_media_add_attr(answer, a_tmp[i]);
}

static int srtp_crypto_cmp(const pjmedia_srtp_crypto* c1,
			   const pjmedia_srtp_crypto* c2)
{
    int r;

    r = pj_strcmp(&c1->key, &c2->key);
    if (r != 0)
	return r;

    r = pj_stricmp(&c1->name, &c2->name);
    if (r != 0)
	return r;

    return (c1->flags != c2->flags);
}

static pj_bool_t mod_stateful_on_rx_request(pjsip_rx_data *rdata)
{
    const pj_str_t stateful_user = { "1", 1 };
    pjsip_uri *uri;
    pjsip_sip_uri *sip_uri;

    uri = pjsip_uri_get_uri(rdata->msg_info.msg->line.req.uri);

    /* Only want to receive SIP/SIPS scheme */
    if (!PJSIP_URI_SCHEME_IS_SIP(uri) && !PJSIP_URI_SCHEME_IS_SIPS(uri))
	return PJ_FALSE;

    sip_uri = (pjsip_sip_uri*) uri;

    /* Check for matching user part */
    if (pj_strcmp(&sip_uri->user, &stateful_user)!=0)
	return PJ_FALSE;

    /*
     * Yes, this is for us.
     * Respond statefully with 200/OK.
     */
    switch (rdata->msg_info.msg->line.req.method.id) {
    case PJSIP_INVITE_METHOD:
	{
	    pjsip_msg_body *body;

	    if (dummy_sdp_str.slen == 0)
		dummy_sdp_str.slen = pj_ansi_strlen(dummy_sdp_str.ptr);

	    body = pjsip_msg_body_create(rdata->tp_info.pool, 
					 &mime_application, &mime_sdp, 
					 &dummy_sdp_str);
	    pjsip_endpt_respond(app.sip_endpt, &mod_stateful_server, rdata,
				200, NULL, NULL, body, NULL);
	}
	break;
    case PJSIP_ACK_METHOD:
	return PJ_TRUE;
    default:
	pjsip_endpt_respond(app.sip_endpt, &mod_stateful_server, rdata,
			    200, NULL, NULL, NULL, NULL);
	break;
    }

    app.server.cur_state.stateful_cnt++;
    return PJ_TRUE;
}

/* Schedule timer to terminate transaction. */
static void schedule_terminate_tsx( pjsip_transaction *tsx,
				    int status_code,
				    int msec_delay )
{
    pj_time_val delay;

    delay.sec = 0;
    delay.msec = msec_delay;
    pj_time_val_normalize(&delay);

    pj_assert(pj_strcmp(&tsx->transaction_key, &tsx_key)==0);
    timer.user_data = NULL;
    timer.id = status_code;
    timer.cb = &terminate_tsx_timer;
    pjsip_endpt_schedule_timer(endpt, &timer, &delay);
}

PJ_DEF(pj_status_t) pjsip_regc_set_via_sent_by( pjsip_regc *regc,
				                pjsip_host_port *via_addr,
                                                pjsip_transport *via_tp)
{
    PJ_ASSERT_RETURN(regc, PJ_EINVAL);

    if (!via_addr)
        pj_bzero(&regc->via_addr, sizeof(regc->via_addr));
    else {
        if (pj_strcmp(&regc->via_addr.host, &via_addr->host))
            pj_strdup(regc->pool, &regc->via_addr.host, &via_addr->host);
        regc->via_addr.port = via_addr->port;
    }
    regc->via_tp = via_tp;

    return PJ_SUCCESS;
}