/*
 * 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 rrc_gNB.c
 * \brief rrc procedures for gNB
 * \author Navid Nikaein and  Raymond Knopp , WEI-TAI CHEN
 * \date 2011 - 2014 , 2018
 * \version 1.0
 * \company Eurecom, NTUST
 * \email: navid.nikaein@eurecom.fr and raymond.knopp@eurecom.fr, kroempa@gmail.com
 */
#define RRC_GNB_C
#define RRC_GNB_C

#include "nr_rrc_config.h"
#include "nr_rrc_defs.h"
#include "nr_rrc_extern.h"
#include "assertions.h"
#include "common/ran_context.h"
#include "asn1_conversions.h"

#include "RRC/L2_INTERFACE/openair_rrc_L2_interface.h"
#include "LAYER2/RLC/rlc.h"
#include "LAYER2/NR_MAC_gNB/mac_proto.h"
#include "common/utils/LOG/log.h"
#include "COMMON/mac_rrc_primitives.h"
#include "RRC/NR/MESSAGES/asn1_msg.h"

#include "NR_BCCH-BCH-Message.h"
#include "NR_UL-DCCH-Message.h"
#include "NR_DL-DCCH-Message.h"
#include "NR_CellGroupConfig.h"
#include "NR_MeasResults.h"
#include "LTE_UECapabilityInformation.h"
#include "LTE_UL-DCCH-Message.h"

#include "rlc.h"
#include "rrc_eNB_UE_context.h"
#include "platform_types.h"
#include "msc.h"
#include "common/utils/LOG/vcd_signal_dumper.h"

#include "T.h"

#include "RRC/NAS/nas_config.h"
#include "RRC/NAS/rb_config.h"
#include "OCG.h"
#include "OCG_extern.h"

#if defined(ENABLE_SECURITY)
  #include "UTIL/OSA/osa_defs.h"
#endif

#include "rrc_eNB_S1AP.h"
#include "rrc_eNB_GTPV1U.h"


#include "pdcp.h"
#include "gtpv1u_eNB_task.h"


#include "intertask_interface.h"
#include "SIMULATION/TOOLS/sim.h" // for taus

#include "executables/softmodem-common.h"
#include <openair2/RRC/NR/rrc_gNB_UE_context.h>

//#define XER_PRINT


extern RAN_CONTEXT_t RC;

mui_t                               rrc_gNB_mui = 0;

///---------------------------------------------------------------------------------------------------------------///
///---------------------------------------------------------------------------------------------------------------///

void openair_nr_rrc_on(const protocol_ctxt_t *const ctxt_pP) {
  LOG_I(NR_RRC, PROTOCOL_NR_RRC_CTXT_FMT" gNB:OPENAIR NR RRC IN....\n",PROTOCOL_NR_RRC_CTXT_ARGS(ctxt_pP));
  rrc_config_nr_buffer (&RC.nrrrc[ctxt_pP->module_id]->carrier.SI, BCCH, 1);
  RC.nrrrc[ctxt_pP->module_id]->carrier.SI.Active = 1;
  rrc_config_nr_buffer (&RC.nrrrc[ctxt_pP->module_id]->carrier.Srb0, CCCH, 1);
  RC.nrrrc[ctxt_pP->module_id]->carrier.Srb0.Active = 1;
}

///---------------------------------------------------------------------------------------------------------------///
///---------------------------------------------------------------------------------------------------------------///

void rrc_gNB_process_SgNBAdditionRequest(
  const protocol_ctxt_t  *const ctxt_pP,
  rrc_gNB_ue_context_t   *ue_context_pP
) {
  rrc_gNB_generate_SgNBAdditionRequestAcknowledge(ctxt_pP,ue_context_pP);
}

void rrc_gNB_generate_SgNBAdditionRequestAcknowledge(
  const protocol_ctxt_t  *const ctxt_pP,
  rrc_gNB_ue_context_t   *const ue_context_pP) {
  //uint8_t size;
  //uint8_t buffer[100];
  //int     CC_id = ue_context_pP->ue_context.primaryCC_id;
  //OCTET_STRING_t                                      *secondaryCellGroup;
  NR_CellGroupConfig_t                                *cellGroupconfig;
  struct NR_CellGroupConfig__rlc_BearerToAddModList   *rlc_BearerToAddModList;
  struct NR_MAC_CellGroupConfig                       *mac_CellGroupConfig;
  struct NR_PhysicalCellGroupConfig                   *physicalCellGroupConfig;
  struct NR_SpCellConfig                              *spCellConfig;
  //struct NR_CellGroupConfig__sCellToAddModList        *sCellToAddModList;
  cellGroupconfig                           = CALLOC(1,sizeof(NR_CellGroupConfig_t));
  cellGroupconfig->rlc_BearerToAddModList   = CALLOC(1,sizeof(struct NR_CellGroupConfig__rlc_BearerToAddModList));
  cellGroupconfig->mac_CellGroupConfig      = CALLOC(1,sizeof(struct NR_MAC_CellGroupConfig));
  cellGroupconfig->physicalCellGroupConfig  = CALLOC(1,sizeof(struct NR_PhysicalCellGroupConfig));
  cellGroupconfig->spCellConfig             = CALLOC(1,sizeof(struct NR_SpCellConfig));
  //cellGroupconfig->sCellToAddModList        = CALLOC(1,sizeof(struct NR_CellGroupConfig__sCellToAddModList));
  rlc_BearerToAddModList   = cellGroupconfig->rlc_BearerToAddModList;
  mac_CellGroupConfig      = cellGroupconfig->mac_CellGroupConfig;
  physicalCellGroupConfig  = cellGroupconfig->physicalCellGroupConfig;
  spCellConfig             = cellGroupconfig->spCellConfig;
  //sCellToAddModList        = cellGroupconfig->sCellToAddModList;
  rlc_bearer_config_t *rlc_config;
  rlc_config = CALLOC(1,sizeof(rlc_bearer_config_t));
  //Fill rlc_bearer config value
  rrc_config_rlc_bearer(ctxt_pP->module_id,
                        ue_context_pP->ue_context.primaryCC_id,
                        rlc_config
                       );
  //Fill rlc_bearer config to structure
  do_RLC_BEARER(ctxt_pP->module_id,
                ue_context_pP->ue_context.primaryCC_id,
                rlc_BearerToAddModList,
                rlc_config);
  mac_cellgroup_t *mac_cellgroup_config;
  mac_cellgroup_config = CALLOC(1,sizeof(mac_cellgroup_t));
  //Fill mac_cellgroup_config config value
  rrc_config_mac_cellgroup(ctxt_pP->module_id,
                           ue_context_pP->ue_context.primaryCC_id,
                           mac_cellgroup_config
                          );
  //Fill mac_cellgroup config to structure
  do_MAC_CELLGROUP(ctxt_pP->module_id,
                   ue_context_pP->ue_context.primaryCC_id,
                   mac_CellGroupConfig,
                   mac_cellgroup_config);
  physicalcellgroup_t *physicalcellgroup_config;
  physicalcellgroup_config = CALLOC(1,sizeof(physicalcellgroup_t));
  //Fill physicalcellgroup_config config value
  rrc_config_physicalcellgroup(ctxt_pP->module_id,
                               ue_context_pP->ue_context.primaryCC_id,
                               physicalcellgroup_config
                              );
  //Fill physicalcellgroup config to structure
  do_PHYSICALCELLGROUP(ctxt_pP->module_id,
                       ue_context_pP->ue_context.primaryCC_id,
                       physicalCellGroupConfig,
                       physicalcellgroup_config);
  do_SpCellConfig(RC.nrrrc[ctxt_pP->module_id],
                  spCellConfig);
}

///---------------------------------------------------------------------------------------------------------------///
///---------------------------------------------------------------------------------------------------------------///

static void init_NR_SI(gNB_RRC_INST *rrc) {
  LOG_D(RRC,"%s()\n\n\n\n",__FUNCTION__);
  rrc->carrier.MIB             = (uint8_t *) malloc16(4);
  rrc->carrier.sizeof_MIB      = do_MIB_NR(rrc,0);
  LOG_I(NR_RRC,"Done init_NR_SI\n");
  rrc_mac_config_req_gNB(rrc->module_id,
                         rrc->carrier.ssb_SubcarrierOffset,
                         rrc->carrier.pdsch_AntennaPorts,
                         rrc->carrier.pusch_TargetSNRx10,
                         rrc->carrier.pucch_TargetSNRx10,
                         (NR_ServingCellConfigCommon_t *)rrc->carrier.servingcellconfigcommon,
                         0,
                         0, // WIP hardcoded rnti
                         (NR_CellGroupConfig_t *)NULL
                        );

  if (get_softmodem_params()->phy_test > 0 || get_softmodem_params()->do_ra > 0) {
    // This is for phytest only, emulate first X2 message if uecap.raw file is present
    FILE *fd;
    fd = fopen("uecap.raw","r");

    if (fd != NULL) {
      char buffer[4096];
      int msg_len=fread(buffer,1,4096,fd);
      LOG_I(RRC,"Read in %d bytes for uecap\n",msg_len);
      LTE_UL_DCCH_Message_t *LTE_UL_DCCH_Message;
      asn_dec_rval_t dec_rval = uper_decode_complete( NULL,
                                &asn_DEF_LTE_UL_DCCH_Message,
                                (void **)&LTE_UL_DCCH_Message,
                                (uint8_t *)buffer,
                                msg_len);

      if ((dec_rval.code != RC_OK) && (dec_rval.consumed == 0)) {
        AssertFatal(1==0,"NR_UL_DCCH_MESSAGE decode error\n");
        // free the memory
        SEQUENCE_free( &asn_DEF_LTE_UL_DCCH_Message, LTE_UL_DCCH_Message, 1 );
        return;
      }

      fclose(fd);
      xer_fprint(stdout,&asn_DEF_LTE_UL_DCCH_Message, LTE_UL_DCCH_Message);
      // recreate enough of X2 EN-DC Container
      AssertFatal(LTE_UL_DCCH_Message->message.choice.c1.present == LTE_UL_DCCH_MessageType__c1_PR_ueCapabilityInformation,
                  "ueCapabilityInformation not present\n");
      NR_CG_ConfigInfo_t *CG_ConfigInfo = calloc(1,sizeof(*CG_ConfigInfo));
      CG_ConfigInfo->criticalExtensions.present = NR_CG_ConfigInfo__criticalExtensions_PR_c1;
      CG_ConfigInfo->criticalExtensions.choice.c1 = calloc(1,sizeof(*CG_ConfigInfo->criticalExtensions.choice.c1));
      CG_ConfigInfo->criticalExtensions.choice.c1->present = NR_CG_ConfigInfo__criticalExtensions__c1_PR_cg_ConfigInfo;
      CG_ConfigInfo->criticalExtensions.choice.c1->choice.cg_ConfigInfo = calloc(1,sizeof(*CG_ConfigInfo->criticalExtensions.choice.c1->choice.cg_ConfigInfo));
      NR_CG_ConfigInfo_IEs_t *cg_ConfigInfo = CG_ConfigInfo->criticalExtensions.choice.c1->choice.cg_ConfigInfo;
      cg_ConfigInfo->ue_CapabilityInfo = calloc(1,sizeof(*cg_ConfigInfo->ue_CapabilityInfo));
      asn_enc_rval_t enc_rval = uper_encode_to_buffer(&asn_DEF_LTE_UE_CapabilityRAT_ContainerList,NULL,
                                (void *)&LTE_UL_DCCH_Message->message.choice.c1.choice.ueCapabilityInformation.criticalExtensions.choice.c1.choice.ueCapabilityInformation_r8.ue_CapabilityRAT_ContainerList,buffer,4096);
      AssertFatal (enc_rval.encoded > 0, "ASN1 message encoding failed (%s, %jd)!\n",
                   enc_rval.failed_type->name, enc_rval.encoded);
      OCTET_STRING_fromBuf(cg_ConfigInfo->ue_CapabilityInfo,
                           (const char *)buffer,
                           (enc_rval.encoded+7)>>3);
      parse_CG_ConfigInfo(rrc,CG_ConfigInfo,NULL);
    } else {
      struct rrc_gNB_ue_context_s *ue_context_p = rrc_gNB_allocate_new_UE_context(rrc);
      LOG_I(NR_RRC,"Adding new user (%p)\n",ue_context_p);
      rrc_add_nsa_user(rrc,ue_context_p,NULL);
    }
  }
}


char openair_rrc_gNB_configuration(const module_id_t gnb_mod_idP, gNB_RrcConfigurationReq *configuration) {
  protocol_ctxt_t      ctxt;
  gNB_RRC_INST         *rrc=RC.nrrrc[gnb_mod_idP];
  PROTOCOL_CTXT_SET_BY_MODULE_ID(&ctxt, gnb_mod_idP, GNB_FLAG_YES, NOT_A_RNTI, 0, 0,gnb_mod_idP);
  LOG_I(NR_RRC,
        PROTOCOL_NR_RRC_CTXT_FMT" Init...\n",
        PROTOCOL_NR_RRC_CTXT_ARGS(&ctxt));

  AssertFatal(rrc != NULL, "RC.nrrrc not initialized!");
  AssertFatal(NUMBER_OF_UE_MAX < (module_id_t)0xFFFFFFFFFFFFFFFF, " variable overflow");
  AssertFatal(configuration!=NULL,"configuration input is null\n");
  rrc->module_id = gnb_mod_idP;
  rrc->Nb_ue = 0;
  rrc->carrier.Srb0.Active = 0;
  nr_uid_linear_allocator_init(&rrc->uid_allocator);
  RB_INIT(&rrc->rrc_ue_head);
  rrc->initial_id2_s1ap_ids = hashtable_create (NUMBER_OF_UE_MAX * 2, NULL, NULL);
  rrc->s1ap_id2_s1ap_ids    = hashtable_create (NUMBER_OF_UE_MAX * 2, NULL, NULL);
  rrc->carrier.servingcellconfigcommon = configuration->scc;
  rrc->carrier.ssb_SubcarrierOffset = configuration->ssb_SubcarrierOffset;
  rrc->carrier.pdsch_AntennaPorts = configuration->pdsch_AntennaPorts;
  rrc->carrier.pusch_TargetSNRx10 = configuration->pusch_TargetSNRx10;
  rrc->carrier.pucch_TargetSNRx10 = configuration->pucch_TargetSNRx10;
  /// System Information INIT
  LOG_I(NR_RRC, PROTOCOL_NR_RRC_CTXT_FMT" Checking release \n",PROTOCOL_NR_RRC_CTXT_ARGS(&ctxt));
  init_NR_SI(rrc);
  rrc_init_nr_global_param();
  openair_nr_rrc_on(&ctxt);
  return 0;
}//END openair_rrc_gNB_configuration


void rrc_gNB_process_AdditionRequestInformation(const module_id_t gnb_mod_idP, x2ap_ENDC_sgnb_addition_req_t *m) {
  struct NR_CG_ConfigInfo *cg_configinfo = NULL;
  asn_dec_rval_t dec_rval = uper_decode_complete(NULL,
                            &asn_DEF_NR_CG_ConfigInfo,
                            (void **)&cg_configinfo,
                            (uint8_t *)m->rrc_buffer,
                            (int) m->rrc_buffer_size);//m->rrc_buffer_size);
  gNB_RRC_INST         *rrc=RC.nrrrc[gnb_mod_idP];

  if ((dec_rval.code != RC_OK) && (dec_rval.consumed == 0)) {
    AssertFatal(1==0,"NR_UL_DCCH_MESSAGE decode error\n");
    // free the memory
    SEQUENCE_free(&asn_DEF_NR_CG_ConfigInfo, cg_configinfo, 1);
    return;
  }

  xer_fprint(stdout,&asn_DEF_NR_CG_ConfigInfo, cg_configinfo);
  // recreate enough of X2 EN-DC Container
  AssertFatal(cg_configinfo->criticalExtensions.choice.c1->present == NR_CG_ConfigInfo__criticalExtensions__c1_PR_cg_ConfigInfo,
              "ueCapabilityInformation not present\n");
  parse_CG_ConfigInfo(rrc,cg_configinfo,m);
}

///---------------------------------------------------------------------------------------------------------------///
///---------------------------------------------------------------------------------------------------------------///
void *rrc_gnb_task(void *args_p) {
  MessageDef                         *msg_p;
  const char                         *msg_name_p;
  instance_t                         instance;
  int                                result;
  //SRB_INFO                           *srb_info_p;
  //int                                CC_id;
  //protocol_ctxt_t                    ctxt;
  itti_mark_task_ready(TASK_RRC_GNB);
  LOG_I(NR_RRC,"Entering main loop of NR_RRC message task\n");

  while (1) {
    // Wait for a message
    itti_receive_msg(TASK_RRC_GNB, &msg_p);
    msg_name_p = ITTI_MSG_NAME(msg_p);
    instance = ITTI_MSG_INSTANCE(msg_p);
    LOG_I(NR_RRC,"Received message %s\n",msg_name_p);

    switch (ITTI_MSG_ID(msg_p)) {
      case TERMINATE_MESSAGE:
        LOG_W(RRC, " *** Exiting NR_RRC thread\n");
        itti_exit_task();
        break;

      case MESSAGE_TEST:
        LOG_I(RRC, "[gNB %d] Received %s\n", instance, msg_name_p);
        break;

      /* Messages from MAC */

      /* Messages from PDCP */

      /*
      #if defined(ENABLE_USE_MME)

            // Messages from S1AP
          case S1AP_DOWNLINK_NAS:
            rrc_eNB_process_S1AP_DOWNLINK_NAS(msg_p, msg_name_p, instance, &rrc_gNB_mui);
            break;

          case S1AP_INITIAL_CONTEXT_SETUP_REQ:
            rrc_eNB_process_S1AP_INITIAL_CONTEXT_SETUP_REQ(msg_p, msg_name_p, instance);
            break;

          case S1AP_UE_CTXT_MODIFICATION_REQ:
            rrc_eNB_process_S1AP_UE_CTXT_MODIFICATION_REQ(msg_p, msg_name_p, instance);
            break;

          case S1AP_PAGING_IND:
            LOG_D(RRC, "[eNB %d] Received Paging message from S1AP: %s\n", instance, msg_name_p);
            rrc_eNB_process_PAGING_IND(msg_p, msg_name_p, instance);
            break;

          case S1AP_E_RAB_SETUP_REQ:
            rrc_eNB_process_S1AP_E_RAB_SETUP_REQ(msg_p, msg_name_p, instance);
            LOG_D(RRC, "[eNB %d] Received the message %s\n", instance, msg_name_p);
            break;

          case S1AP_E_RAB_MODIFY_REQ:
            rrc_eNB_process_S1AP_E_RAB_MODIFY_REQ(msg_p, msg_name_p, instance);
            break;

          case S1AP_E_RAB_RELEASE_COMMAND:
            rrc_eNB_process_S1AP_E_RAB_RELEASE_COMMAND(msg_p, msg_name_p, instance);
            break;

          case S1AP_UE_CONTEXT_RELEASE_REQ:
            rrc_eNB_process_S1AP_UE_CONTEXT_RELEASE_REQ(msg_p, msg_name_p, instance);
            break;

          case S1AP_UE_CONTEXT_RELEASE_COMMAND:
            rrc_eNB_process_S1AP_UE_CONTEXT_RELEASE_COMMAND(msg_p, msg_name_p, instance);
            break;

          case GTPV1U_ENB_DELETE_TUNNEL_RESP:
            ///Nothing to do. Apparently everything is done in S1AP processing
            //LOG_I(RRC, "[eNB %d] Received message %s, not processed because procedure not synched\n",
            //instance, msg_name_p);
            if (rrc_eNB_get_ue_context(RC.nrrrc[instance], GTPV1U_ENB_DELETE_TUNNEL_RESP(msg_p).rnti)
                && rrc_eNB_get_ue_context(RC.nrrrc[instance], GTPV1U_ENB_DELETE_TUNNEL_RESP(msg_p).rnti)->ue_context.ue_release_timer_rrc > 0) {
              rrc_eNB_get_ue_context(RC.nrrrc[instance], GTPV1U_ENB_DELETE_TUNNEL_RESP(msg_p).rnti)->ue_context.ue_release_timer_rrc =
              rrc_eNB_get_ue_context(RC.nrrrc[instance], GTPV1U_ENB_DELETE_TUNNEL_RESP(msg_p).rnti)->ue_context.ue_release_timer_thres_rrc;
            }
            break;

      #endif
      */
      /* Messages from gNB app */
      case NRRRC_CONFIGURATION_REQ:
        LOG_I(NR_RRC, "[gNB %d] Received %s : %p\n", instance, msg_name_p,&NRRRC_CONFIGURATION_REQ(msg_p));
        openair_rrc_gNB_configuration(GNB_INSTANCE_TO_MODULE_ID(instance), &NRRRC_CONFIGURATION_REQ(msg_p));
        break;

      /* Messages from X2AP */
      case X2AP_ENDC_SGNB_ADDITION_REQ:
        LOG_I(NR_RRC, "Received ENDC sgNB addition request from X2AP \n");
        rrc_gNB_process_AdditionRequestInformation(GNB_INSTANCE_TO_MODULE_ID(instance), &X2AP_ENDC_SGNB_ADDITION_REQ(msg_p));
        break;

      case X2AP_ENDC_SGNB_RECONF_COMPLETE:
        LOG_I(NR_RRC, "Handling of reconfiguration complete message at RRC gNB is pending \n");
        break;

      default:
        LOG_E(NR_RRC, "[gNB %d] Received unexpected message %s\n", instance, msg_name_p);
        break;
    }

    result = itti_free(ITTI_MSG_ORIGIN_ID(msg_p), msg_p);
    AssertFatal(result == EXIT_SUCCESS, "Failed to free memory (%d)!\n", result);
    msg_p = NULL;
  }
}

