/*
 * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The OpenAirInterface Software Alliance licenses this file to You under
 * the OAI Public License, Version 1.1  (the "License"); you may not use this file
 * except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.openairinterface.org/?page_id=698
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *-------------------------------------------------------------------------------
 * For more information about the OpenAirInterface (OAI) Software Alliance:
 *      contact@openairinterface.org
 */

/*! \file f1ap_du_rrc_message_transfer.c
 * \brief f1ap rrc message transfer for DU
 * \author EURECOM/NTUST
 * \date 2018
 * \version 0.1
 * \company Eurecom
 * \email: navid.nikaein@eurecom.fr, bing-kai.hong@eurecom.fr
 * \note
 * \warning
 */

#include "f1ap_common.h"
#include "f1ap_encoder.h"
#include "f1ap_decoder.h"
#include "f1ap_itti_messaging.h"
#include "f1ap_du_rrc_message_transfer.h"

// undefine C_RNTI from
// openair1/PHY/LTE_TRANSPORT/transport_common.h which
// replaces in ie->value.choice.C_RNTI, causing
// a compile error
#undef C_RNTI 

extern f1ap_setup_req_t *f1ap_du_data;


f1ap_cudu_ue_inst_t f1ap_du_ue[MAX_eNB];



/*  DL RRC Message Transfer */
int DU_handle_DL_RRC_MESSAGE_TRANSFER(instance_t       instance,
                                      uint32_t         assoc_id,
                                      uint32_t         stream,
                                      F1AP_F1AP_PDU_t *pdu) {

  LOG_D(DU_F1AP, "DU_handle_DL_RRC_MESSAGE_TRANSFER \n");
  
  MessageDef                     *message_p;
  F1AP_DLRRCMessageTransfer_t    *container;
  F1AP_DLRRCMessageTransferIEs_t *ie;

  uint8_t  *buffer;
  uint32_t  len;
  
  uint64_t        cu_ue_f1ap_id;
  uint64_t        du_ue_f1ap_id;
  uint64_t        srb_id;
  int             executeDuplication;
  sdu_size_t      ccch_sdu_len;
  uint64_t        subscriberProfileIDforRFP;
  uint64_t        rAT_FrequencySelectionPriority;

  DevAssert(pdu != NULL);
  
  if (stream != 0) {
    LOG_E(F1AP, "[SCTP %d] Received F1 on stream != 0 (%d)\n",
               assoc_id, stream);
    return -1;
  }

  container = &pdu->choice.initiatingMessage->value.choice.DLRRCMessageTransfer;


  /* GNB_CU_UE_F1AP_ID */
  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_DLRRCMessageTransferIEs_t, ie, container,
                             F1AP_ProtocolIE_ID_id_gNB_CU_UE_F1AP_ID, true);
  cu_ue_f1ap_id = ie->value.choice.GNB_CU_UE_F1AP_ID;
  LOG_D(DU_F1AP, "cu_ue_f1ap_id %lu \n", cu_ue_f1ap_id);


  /* GNB_DU_UE_F1AP_ID */
  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_DLRRCMessageTransferIEs_t, ie, container,
                             F1AP_ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID, true);
  du_ue_f1ap_id = ie->value.choice.GNB_DU_UE_F1AP_ID;
  LOG_D(DU_F1AP, "du_ue_f1ap_id %lu associated with UE RNTI %x \n", 
                  du_ue_f1ap_id,   
                  f1ap_get_rnti_by_du_id(&f1ap_du_ue[instance],du_ue_f1ap_id)); // this should be the one transmitted via initial ul rrc message transfer 

  if (f1ap_du_add_cu_ue_id(&f1ap_du_ue[instance],du_ue_f1ap_id,cu_ue_f1ap_id) < 0 ) {
    LOG_E(DU_F1AP, "Failed to find the F1AP UID \n");
    //return -1;
  }

  /* optional */
  /* oldgNB_DU_UE_F1AP_ID */
  if (0) {
    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_DLRRCMessageTransferIEs_t, ie, container,
                             F1AP_ProtocolIE_ID_id_oldgNB_DU_UE_F1AP_ID, true);
  }

  /* mandatory */
  /* SRBID */
  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_DLRRCMessageTransferIEs_t, ie, container,
                             F1AP_ProtocolIE_ID_id_SRBID, true);
  srb_id = ie->value.choice.SRBID;
  LOG_D(DU_F1AP, "srb_id %lu \n", srb_id);

  /* optional */
  /* ExecuteDuplication */
  if (0) {
    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_DLRRCMessageTransferIEs_t, ie, container,
                             F1AP_ProtocolIE_ID_id_ExecuteDuplication, true);
    executeDuplication = ie->value.choice.ExecuteDuplication;
    LOG_D(DU_F1AP, "ExecuteDuplication %d \n", executeDuplication);
  }

  // issue in here
  /* mandatory */
  /* RRC Container */
  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_DLRRCMessageTransferIEs_t, ie, container,
                             F1AP_ProtocolIE_ID_id_RRCContainer, true);
  // BK: need check
  // create an ITTI message and copy SDU
  message_p = itti_alloc_new_message (TASK_DU_F1, RRC_MAC_CCCH_DATA_IND);
  memset (RRC_MAC_CCCH_DATA_IND (message_p).sdu, 0, CCCH_SDU_SIZE);
  ccch_sdu_len = ie->value.choice.RRCContainer.size;
  memcpy(RRC_MAC_CCCH_DATA_IND (message_p).sdu, ie->value.choice.RRCContainer.buf,
         ccch_sdu_len);
  LOG_D(DU_F1AP, "RRCContainer(CCCH) :");
  for (int i=0;i<ie->value.choice.RRCContainer.size;i++) LOG_D(DU_F1AP, "%2x ",RRC_MAC_CCCH_DATA_IND (message_p).sdu[i]);
  LOG_D(DU_F1AP, "\n");

  /* optional */
  /* RAT_FrequencyPriorityInformation */
  if (0) {
    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_DLRRCMessageTransferIEs_t, ie, container,
                             F1AP_ProtocolIE_ID_id_RAT_FrequencyPriorityInformation, true);

    switch(ie->value.choice.RAT_FrequencyPriorityInformation.present) {
      case F1AP_RAT_FrequencyPriorityInformation_PR_subscriberProfileIDforRFP:
        subscriberProfileIDforRFP = ie->value.choice.RAT_FrequencyPriorityInformation.choice.subscriberProfileIDforRFP;
        break;
      case F1AP_RAT_FrequencyPriorityInformation_PR_rAT_FrequencySelectionPriority:
        rAT_FrequencySelectionPriority = ie->value.choice.RAT_FrequencyPriorityInformation.choice.rAT_FrequencySelectionPriority;
        break;
    }
  }

  return 0;
  
}

int DU_send_UL_RRC_MESSAGE_TRANSFER(instance_t                instance,
                                    f1ap_ul_rrc_message_t    *f1ap_ul_rrc) {

  LOG_D(DU_F1AP, "DU_send_UL_RRC_MESSAGE_TRANSFER \n");

  F1AP_F1AP_PDU_t                pdu;
  F1AP_ULRRCMessageTransfer_t    *out;
  F1AP_ULRRCMessageTransferIEs_t *ie;

  uint8_t  *buffer;
  uint32_t  len;

  /* Create */
  /* 0. Message Type */
  memset(&pdu, 0, sizeof(pdu));
  pdu.present = F1AP_F1AP_PDU_PR_initiatingMessage;
  pdu.choice.initiatingMessage = (F1AP_InitiatingMessage_t *)calloc(1, sizeof(F1AP_InitiatingMessage_t));
  pdu.choice.initiatingMessage->procedureCode = F1AP_ProcedureCode_id_ULRRCMessageTransfer;
  pdu.choice.initiatingMessage->criticality   = F1AP_Criticality_ignore;
  pdu.choice.initiatingMessage->value.present = F1AP_InitiatingMessage__value_PR_ULRRCMessageTransfer;
  out = &pdu.choice.initiatingMessage->value.choice.ULRRCMessageTransfer;
  
  /* mandatory */
  /* c1. GNB_CU_UE_F1AP_ID */
  ie = (F1AP_ULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_ULRRCMessageTransferIEs_t));
  ie->id                             = F1AP_ProtocolIE_ID_id_gNB_CU_UE_F1AP_ID;
  ie->criticality                    = F1AP_Criticality_reject;
  ie->value.present                  = F1AP_ULRRCMessageTransferIEs__value_PR_GNB_CU_UE_F1AP_ID;
  ie->value.choice.GNB_CU_UE_F1AP_ID = f1ap_du_ue[instance].cu_ue_f1ap_id[f1ap_get_uid_by_rnti(&f1ap_du_ue[instance], f1ap_ul_rrc->rnti)];
  ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);

  /* mandatory */
  /* c2. GNB_DU_UE_F1AP_ID */
  ie = (F1AP_ULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_ULRRCMessageTransferIEs_t));
  ie->id                             = F1AP_ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID;
  ie->criticality                    = F1AP_Criticality_reject;
  ie->value.present                  = F1AP_ULRRCMessageTransferIEs__value_PR_GNB_DU_UE_F1AP_ID;
  ie->value.choice.GNB_DU_UE_F1AP_ID = f1ap_du_ue[instance].du_ue_f1ap_id[f1ap_get_uid_by_rnti(&f1ap_du_ue[instance], f1ap_ul_rrc->rnti)];
  ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);

  /* mandatory */
  /* c3. SRBID */
  ie = (F1AP_ULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_ULRRCMessageTransferIEs_t));
  ie->id                            = F1AP_ProtocolIE_ID_id_SRBID;
  ie->criticality                   = F1AP_Criticality_reject;
  ie->value.present                 = F1AP_ULRRCMessageTransferIEs__value_PR_SRBID;
  ie->value.choice.SRBID            = f1ap_ul_rrc->srb_id;
  ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);

  // issue in here
  /* mandatory */
  /* c4. RRCContainer */
  ie = (F1AP_ULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_ULRRCMessageTransferIEs_t));
  ie->id                            = F1AP_ProtocolIE_ID_id_RRCContainer;
  ie->criticality                   = F1AP_Criticality_reject;
  ie->value.present                 = F1AP_ULRRCMessageTransferIEs__value_PR_RRCContainer;
  OCTET_STRING_fromBuf(&ie->value.choice.RRCContainer, f1ap_ul_rrc->rrc_container, f1ap_ul_rrc->rrc_container_length);
  ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);

    /* encode */
  if (f1ap_encode_pdu(&pdu, &buffer, &len) < 0) {
    LOG_E(DU_F1AP, "Failed to encode F1 setup request\n");
    return -1;
  }

  du_f1ap_itti_send_sctp_data_req(instance, f1ap_du_data->assoc_id, buffer, len, f1ap_du_data->default_sctp_stream_id);
  return 0;
}


/*  UL RRC Message Transfer */
int DU_send_INITIAL_UL_RRC_MESSAGE_TRANSFER(module_id_t     module_idP,
                                            int             CC_idP,
                                            int             UE_id,
                                            rnti_t          rntiP,
                                            uint8_t        *sduP,
                                            sdu_size_t      sdu_lenP) {

  F1AP_F1AP_PDU_t                       pdu;
  F1AP_InitialULRRCMessageTransfer_t    *out;
  F1AP_InitialULRRCMessageTransferIEs_t *ie;

  uint8_t  *buffer;
  uint32_t  len;
  int f1ap_uid = f1ap_add_ue (&f1ap_du_ue[module_idP], module_idP, CC_idP,UE_id, rntiP);

  if (f1ap_uid  < 0 ) {
    LOG_E(DU_F1AP, "Failed to add UE \n");
    return -1;
  }

  /* Create */
  /* 0. Message Type */
  memset(&pdu, 0, sizeof(pdu));
  pdu.present = F1AP_F1AP_PDU_PR_initiatingMessage;
  pdu.choice.initiatingMessage = (F1AP_InitiatingMessage_t *)calloc(1, sizeof(F1AP_InitiatingMessage_t));
  pdu.choice.initiatingMessage->procedureCode = F1AP_ProcedureCode_id_InitialULRRCMessageTransfer;
  pdu.choice.initiatingMessage->criticality   = F1AP_Criticality_ignore;
  pdu.choice.initiatingMessage->value.present = F1AP_InitiatingMessage__value_PR_InitialULRRCMessageTransfer;
  out = &pdu.choice.initiatingMessage->value.choice.InitialULRRCMessageTransfer;
  

  /* mandatory */
  /* c1. GNB_DU_UE_F1AP_ID */
  ie = (F1AP_InitialULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_InitialULRRCMessageTransferIEs_t));
  ie->id                             = F1AP_ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID;
  ie->criticality                    = F1AP_Criticality_reject;
  ie->value.present                  = F1AP_InitialULRRCMessageTransferIEs__value_PR_GNB_DU_UE_F1AP_ID;
  ie->value.choice.GNB_DU_UE_F1AP_ID = f1ap_du_ue[module_idP].du_ue_f1ap_id[f1ap_uid]; 
  ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);

  /* mandatory */
  /* c2. NRCGI */
  ie = (F1AP_InitialULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_InitialULRRCMessageTransferIEs_t));
  ie->id                             = F1AP_ProtocolIE_ID_id_NRCGI;
  ie->criticality                    = F1AP_Criticality_reject;
  ie->value.present                  = F1AP_InitialULRRCMessageTransferIEs__value_PR_NRCGI;

  F1AP_NRCGI_t nRCGI;
  MCC_MNC_TO_PLMNID(f1ap_du_data->mcc[0], f1ap_du_data->mnc[0], f1ap_du_data->mnc_digit_length[0],
                                         &nRCGI.pLMN_Identity);
  NR_CELL_ID_TO_BIT_STRING(f1ap_du_data->nr_cellid[0], &nRCGI.nRCellIdentity);
  ie->value.choice.NRCGI = nRCGI;

  ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);

  /* mandatory */
  /* c3. C_RNTI */  // 16
  ie = (F1AP_InitialULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_InitialULRRCMessageTransferIEs_t));
  ie->id                             = F1AP_ProtocolIE_ID_id_C_RNTI;
  ie->criticality                    = F1AP_Criticality_reject;
  ie->value.present                  = F1AP_InitialULRRCMessageTransferIEs__value_PR_C_RNTI;
  C_RNTI_TO_BIT_STRING(rntiP, &ie->value.choice.C_RNTI);
  ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);

  /* mandatory */
  /* c4. RRCContainer */
  ie = (F1AP_InitialULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_InitialULRRCMessageTransferIEs_t));
  ie->id                            = F1AP_ProtocolIE_ID_id_RRCContainer;
  ie->criticality                   = F1AP_Criticality_reject;
  ie->value.present                 = F1AP_InitialULRRCMessageTransferIEs__value_PR_RRCContainer;
  OCTET_STRING_fromBuf(&ie->value.choice.RRCContainer, sduP, sdu_lenP);
  ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);

  /* optional */
  /* c5. DUtoCURRCContainer */
  if (0) {
    ie = (F1AP_InitialULRRCMessageTransferIEs_t *)calloc(1, sizeof(F1AP_InitialULRRCMessageTransferIEs_t));
    ie->id                             = F1AP_ProtocolIE_ID_id_DUtoCURRCContainer;
    ie->criticality                    = F1AP_Criticality_reject;
    ie->value.present                  = F1AP_InitialULRRCMessageTransferIEs__value_PR_DUtoCURRCContainer;
    OCTET_STRING_fromBuf(&ie->value.choice.DUtoCURRCContainer, "dummy_val",
                       strlen("dummy_val"));
    ASN_SEQUENCE_ADD(&out->protocolIEs.list, ie);
  }

    /* encode */
  if (f1ap_encode_pdu(&pdu, &buffer, &len) < 0) {
    LOG_E(DU_F1AP, "Failed to encode F1 setup request\n");
    return -1;
  }

  du_f1ap_itti_send_sctp_data_req(module_idP, f1ap_du_data->assoc_id, buffer, len, f1ap_du_data->default_sctp_stream_id);
  return 0;
}


void init_f1ap_du_ue_inst (void) {

   memset(f1ap_du_ue, 0, sizeof(f1ap_du_ue));
}