/*
 * Copyright (C) 2019-2022 by Sukchan Lee <acetcom@gmail.com>
 *
 * This file is part of Open5GS.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 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, see <https://www.gnu.org/licenses/>.
 */

#include "sbi-path.h"
#include "nas-path.h"
#include "ngap-path.h"
#include "nnrf-handler.h"

void amf_nnrf_handle_nf_discover(
        ogs_sbi_xact_t *xact, ogs_sbi_message_t *recvmsg)
{
    ogs_sbi_nf_instance_t *nf_instance = NULL;
    ogs_sbi_object_t *sbi_object = NULL;
    ogs_sbi_service_type_e service_type = OGS_SBI_SERVICE_TYPE_NULL;
    ogs_sbi_discovery_option_t *discovery_option = NULL;

    OpenAPI_search_result_t *SearchResult = NULL;

    ogs_assert(recvmsg);
    ogs_assert(xact);
    sbi_object = xact->sbi_object;
    ogs_assert(sbi_object);
    service_type = xact->service_type;
    ogs_assert(service_type);

    discovery_option = xact->discovery_option;

    SearchResult = recvmsg->SearchResult;
    if (!SearchResult) {
        ogs_error("No SearchResult");
        return;
    }

    ogs_nnrf_handle_nf_discover_search_result(SearchResult);

    amf_sbi_select_nf(sbi_object, service_type, discovery_option);

    nf_instance = sbi_object->service_type_array[service_type].nf_instance;
    if (!nf_instance) {
        amf_ue_t *amf_ue = NULL;
        amf_sess_t *sess = NULL;

        ogs_assert(sbi_object->type > OGS_SBI_OBJ_BASE &&
                    sbi_object->type < OGS_SBI_OBJ_TOP);
        switch(sbi_object->type) {
        case OGS_SBI_OBJ_UE_TYPE:
            amf_ue = (amf_ue_t *)sbi_object;
            ogs_assert(amf_ue);
            ogs_error("[%s] (NF discover) No [%s]", amf_ue->suci,
                        ogs_sbi_service_type_to_name(service_type));
            ogs_assert(OGS_OK ==
                nas_5gs_send_gmm_reject_from_sbi(amf_ue,
                    OGS_SBI_HTTP_STATUS_GATEWAY_TIMEOUT));
            break;
        case OGS_SBI_OBJ_SESS_TYPE:
            sess = (amf_sess_t *)sbi_object;
            ogs_assert(sess);
            ogs_error("[%d:%d] (NF discover) No [%s]", sess->psi, sess->pti,
                        ogs_sbi_service_type_to_name(service_type));
            if (sess->payload_container_type) {
                ogs_assert(OGS_OK ==
                    nas_5gs_send_back_gsm_message(sess,
                        OGS_5GMM_CAUSE_PAYLOAD_WAS_NOT_FORWARDED,
                        AMF_NAS_BACKOFF_TIME));
            } else {
                ogs_assert(OGS_OK ==
                    ngap_send_error_indication2(amf_ue,
                        NGAP_Cause_PR_transport,
                        NGAP_CauseTransport_transport_resource_unavailable));
            }
            break;
        default:
            ogs_fatal("(NF discover) Not implemented [%s:%d]",
                ogs_sbi_service_type_to_name(service_type), sbi_object->type);
            ogs_assert_if_reached();
        }

        return;
    }

    ogs_expect(true == amf_sbi_send_request(nf_instance, xact));
}