/*
 * 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
 */

#include "ran_func_kpm.h"
#include "openair2/E2AP/flexric/test/rnd/fill_rnd_data_kpm.h"  // this dependancy will be taken out once RAN Function Definition is implemented
#include "openair2/E2AP/flexric/src/util/time_now_us.h"
#include "common/utils/assertions.h"

#if defined (NGRAN_GNB_DU)
#include "openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h"
#include "openair2/LAYER2/nr_rlc/nr_rlc_entity.h"
#include "openair2/LAYER2/nr_rlc/nr_rlc_oai_api.h"
#endif

#if defined (NGRAN_GNB_CUCP)
#include "openair2/RRC/NR/rrc_gNB_UE_context.h"
#include "openair3/NGAP/ngap_gNB_ue_context.h"
#endif

#if defined (NGRAN_GNB_CUUP)
#include "openair2/LAYER2/nr_pdcp/nr_pdcp_entity.h"
#include "openair2/LAYER2/nr_pdcp/nr_pdcp_oai_api.h"
#include "openair2/E1AP/e1ap_common.h"
#endif

#include "openair2/F1AP/f1ap_ids.h"
#include <assert.h>
#include <stdio.h>

/* Please note that only one executable nr-softmodem exists for DU, CU, CU-CP and gNB-mono nodes;
  the layer separation should be done better in the future */

#if defined (NGRAN_GNB_CUUP)  
typedef struct uldlcounter {
  uint32_t dl;
  uint32_t ul;
} uldlcounter_t;

static bool nssai_matches(nssai_t a_nssai, uint8_t b_sst, const uint32_t *b_sd)
{
  AssertFatal(b_sd == NULL || *b_sd <= 0xffffff, "illegal SD %d\n", *b_sd);
  if (b_sd == NULL) {
    return a_nssai.sst == b_sst && a_nssai.sd == 0xffffff;
  } else {
    return a_nssai.sst == b_sst && a_nssai.sd == *b_sd;
  }
}

static uldlcounter_t last_pdcp_sdu_total_bytes[MAX_MOBILES_PER_GNB] = {0};

static gnb_cu_up_e2sm_t fill_gnb_cu_up_data(const ue_id_t cucp_ue_id) 
{
  gnb_cu_up_e2sm_t gnb_cu_up = {0};

  // 6.2.3.20
  // Mandatory
  gnb_cu_up.gnb_cu_cp_ue_e1ap = cucp_ue_id;

  // 6.2.3.25
  // RAN UE ID
  // Optional
  gnb_cu_up.ran_ue_id = NULL;

  return gnb_cu_up;
}

typedef struct {
  ue_id_t pdcp_ue_id_list[MAX_MOBILES_PER_GNB]; // list of matched UEs on PDCP-U level
  size_t num_ues;

} matched_ues_pdcp_t;

 __attribute__((unused))
static size_t filter_ues_by_s_nssai_in_cuup(test_cond_e const condition, uint8_t sst, const uint32_t *sd, matched_ues_pdcp_t* matches)
{
  DevAssert(matches != NULL);
  AssertFatal(condition == EQUAL_TEST_COND, "Condition %d not yet implemented\n", condition);

  // Get NSSAI info from E1 context
  const instance_t CUuniqInstance = 0;
  const e1ap_upcp_inst_t *e1inst = getCxtE1(CUuniqInstance);

  // currently the CU-UP does not store the slices, so we can only do this "coarse filtering"
  for(int s = 0; s < e1inst->cuup.setupReq.plmn[0].supported_slices; s++) {
    if (nssai_matches(e1inst->cuup.setupReq.plmn[0].slice[s], sst, sd)) {
      matches->num_ues = nr_pdcp_get_num_ues(matches->pdcp_ue_id_list, MAX_MOBILES_PER_GNB);
    }
  }
  
  return matches->num_ues;
}

static nr_pdcp_statistics_t get_pdcp_stats_per_drb(const uint32_t rrc_ue_id)
{
  nr_pdcp_statistics_t pdcp = {0};
  const int srb_flag = 0;
  const int rb_id = 1;  // at the moment, only 1 DRB is supported

  // Get PDCP stats for specific DRB
  const bool rc = nr_pdcp_get_statistics(rrc_ue_id, srb_flag, rb_id, &pdcp);
  assert(rc == true && "Cannot get PDCP stats\n");

  return pdcp;
}

static meas_record_lst_t fill_ue_pdcp_data(const uint32_t rrc_ue_id, const size_t ue_idx, const char * meas_info_name_str)
{
  meas_record_lst_t meas_record = {0};

  // Get PDCP stats per DRB
  nr_pdcp_statistics_t pdcp = get_pdcp_stats_per_drb(rrc_ue_id);

  // Measurement Type as requested in Action Definition
  if (strcmp(meas_info_name_str, "DRB.PdcpSduVolumeDL") == 0) {  //  3GPP TS 28.522 - section 5.1.2.1.1.1
    meas_record.value = INTEGER_MEAS_VALUE;

    // Get DL data volume delivered to PDCP layer
    meas_record.int_val = (pdcp.rxsdu_bytes - last_pdcp_sdu_total_bytes[ue_idx].dl)*8/1000;   // [kb]
    last_pdcp_sdu_total_bytes[ue_idx].dl = pdcp.rxsdu_bytes;
    /* note: this measurement is calculated as per spec */
  } else if (strcmp(meas_info_name_str, "DRB.PdcpSduVolumeUL") == 0) {  //  3GPP TS 28.522 - section 5.1.2.1.2.1
    meas_record.value = INTEGER_MEAS_VALUE;

    // Get UL data volume delivered from PDCP layer
    meas_record.int_val = (pdcp.txsdu_bytes - last_pdcp_sdu_total_bytes[ue_idx].ul)*8/1000;   // [kb]
    last_pdcp_sdu_total_bytes[ue_idx].ul = pdcp.txsdu_bytes;
    /* note: this measurement is calculated as per spec */
  } else {
    assert(false && "Measurement Name not yet implemented");
  }
  

  return meas_record;
}

static kpm_ind_msg_format_1_t fill_kpm_ind_msg_frm_1_in_cu(const uint32_t rrc_ue_id, const size_t ue_idx, const kpm_act_def_format_1_t * act_def_fr_1)
{
  kpm_ind_msg_format_1_t msg_frm_1 = {0};
  
  // Measurement Data contains a set of Meas Records, each collected at each granularity period
  msg_frm_1.meas_data_lst_len = 1;  /*  this value is equal to (kpm_ric_event_trigger_format_1.report_period_ms/act_def_fr_1->gran_period_ms)
                                        please, check their values in xApp */
  
  msg_frm_1.meas_data_lst = calloc(msg_frm_1.meas_data_lst_len, sizeof(*msg_frm_1.meas_data_lst));
  assert(msg_frm_1.meas_data_lst != NULL && "Memory exhausted" );

  for (size_t i = 0; i<msg_frm_1.meas_data_lst_len; i++) {
    // Measurement Record
    msg_frm_1.meas_data_lst[i].meas_record_len = act_def_fr_1->meas_info_lst_len;  // record data list length corresponds to info list length from action definition

    msg_frm_1.meas_data_lst[i].meas_record_lst = calloc(msg_frm_1.meas_data_lst[i].meas_record_len, sizeof(meas_record_lst_t));
    assert(msg_frm_1.meas_data_lst[i].meas_record_lst != NULL && "Memory exhausted");

    for (size_t j = 0; j < msg_frm_1.meas_data_lst[i].meas_record_len; j++) { // each meas record corresponds to one meas type
      // Measurement Type as requested in Action Definition
      switch (act_def_fr_1->meas_info_lst[j].meas_type.type) {
      case NAME_MEAS_TYPE: {
        char meas_info_name_str[act_def_fr_1->meas_info_lst[j].meas_type.name.len + 1];
        memcpy(meas_info_name_str, act_def_fr_1->meas_info_lst[j].meas_type.name.buf, act_def_fr_1->meas_info_lst[j].meas_type.name.len);
        meas_info_name_str[act_def_fr_1->meas_info_lst[j].meas_type.name.len] = '\0';

        msg_frm_1.meas_data_lst[i].meas_record_lst[j] = fill_ue_pdcp_data(rrc_ue_id, ue_idx, meas_info_name_str);
        break;
      }
      case ID_MEAS_TYPE:
        assert(false && "ID Measurement Type not yet implemented");
      
      default:
        assert(false && "Measurement Type not recognized");
      }
    }
  }

  // Measurement Information - OPTIONAL
  msg_frm_1.meas_info_lst_len = act_def_fr_1->meas_info_lst_len;
  msg_frm_1.meas_info_lst = calloc(msg_frm_1.meas_info_lst_len, sizeof(meas_info_format_1_lst_t));
  assert(msg_frm_1.meas_info_lst != NULL && "Memory exhausted");
  for (size_t i = 0; i < msg_frm_1.meas_info_lst_len; i++) {
    msg_frm_1.meas_info_lst[i] = cp_meas_info_format_1_lst(&act_def_fr_1->meas_info_lst[i]);
  }

  return msg_frm_1;
}

 __attribute__((unused))
static kpm_ind_msg_format_3_t fill_kpm_ind_msg_frm_3_in_cuup(const matched_ues_pdcp_t* matched_ues,
                                                             const kpm_act_def_format_1_t* act_def_fr_1)
{
  assert(act_def_fr_1 != NULL);

  kpm_ind_msg_format_3_t msg_frm_3 = {0};

  // Fill UE Measurement Reports

  msg_frm_3.ue_meas_report_lst_len = matched_ues->num_ues;
  msg_frm_3.meas_report_per_ue = calloc(msg_frm_3.ue_meas_report_lst_len, sizeof(meas_report_per_ue_t));
  assert(msg_frm_3.meas_report_per_ue != NULL && "Memory exhausted");

  for (size_t i = 0; i<msg_frm_3.ue_meas_report_lst_len; i++) {
    // Fill UE ID data
    msg_frm_3.meas_report_per_ue[i].ue_meas_report_lst.type = GNB_CU_UP_UE_ID_E2SM;
    msg_frm_3.meas_report_per_ue[i].ue_meas_report_lst.gnb_cu_up = fill_gnb_cu_up_data(matched_ues->pdcp_ue_id_list[i]);

    // Fill UE related info
    msg_frm_3.meas_report_per_ue[i].ind_msg_format_1 =
        fill_kpm_ind_msg_frm_1_in_cu(matched_ues->pdcp_ue_id_list[i], i, act_def_fr_1);
  }

  return msg_frm_3;
}
#endif

#if defined (NGRAN_GNB_DU)
static uldlcounter_t last_rlc_pdu_total_bytes[MAX_MOBILES_PER_GNB] = {0};
static uldlcounter_t last_total_prbs[MAX_MOBILES_PER_GNB] = {0};

static gnb_e2sm_t fill_gnb_data(rrc_gNB_ue_context_t * ue_context_p)
{
  gnb_e2sm_t gnb = {0};

  // 6.2.3.16
  // Mandatory
  // AMF UE NGAP ID
  gnb.amf_ue_ngap_id = ue_context_p->ue_context.rrc_ue_id;

  // Mandatory
  //GUAMI 6.2.3.17 
  gnb.guami.plmn_id = (e2sm_plmn_t) {
                                    .mcc = ue_context_p->ue_context.ue_guami.mcc,
                                    .mnc = ue_context_p->ue_context.ue_guami.mnc,
                                    .mnc_digit_len = ue_context_p->ue_context.ue_guami.mnc_len
                                    };
  
  gnb.guami.amf_region_id = ue_context_p->ue_context.ue_guami.amf_region_id;
  gnb.guami.amf_set_id = ue_context_p->ue_context.ue_guami.amf_set_id;
  gnb.guami.amf_ptr = ue_context_p->ue_context.ue_guami.amf_pointer;

  // gNB-CU UE F1AP ID List
  // C-ifCUDUseparated 
  if (NODE_IS_CU(RC.nrrrc[0]->node_type)) {
    gnb.gnb_cu_ue_f1ap_lst_len = 1;
    gnb.gnb_cu_ue_f1ap_lst = calloc(gnb.gnb_cu_ue_f1ap_lst_len, sizeof(uint32_t));
    assert(gnb.gnb_cu_ue_f1ap_lst != NULL);

    for (size_t i = 0; i < gnb.gnb_cu_ue_f1ap_lst_len; i++) {
      gnb.gnb_cu_ue_f1ap_lst[i] = ue_context_p->ue_context.rrc_ue_id;
    }
  }

  return gnb;
}

static gnb_du_e2sm_t fill_gnb_du_data(const f1_ue_data_t * rrc_ue_id)
{
  gnb_du_e2sm_t gnb_du = {0};

  // 6.2.3.21
  // gNB CU UE F1AP
  // Mandatory
  gnb_du.gnb_cu_ue_f1ap = rrc_ue_id->secondary_ue;

  // 6.2.3.25
  // RAN UE ID
  // Optional
  gnb_du.ran_ue_id = NULL;

  return gnb_du;
}
typedef struct {
  NR_UE_info_t* ue_list[MAX_MOBILES_PER_GNB];
  size_t num_ues;
} matched_ues_mac_t;

static size_t filter_ues_by_s_nssai_in_du_or_monolithic(test_cond_e const condition,
                                                        uint8_t sst,
                                                        const uint32_t *sd,
                                                        matched_ues_mac_t* matches)
{
  DevAssert(matches != NULL);
  AssertFatal(condition == EQUAL_TEST_COND, "Condition %d not yet implemented", condition);

  // Take MAC info
  size_t i = 0;
  UE_iterator (RC.nrmac[0]->UE_info.list, ue) {
    NR_UE_sched_ctrl_t *sched_ctrl = &ue->UE_sched_ctrl;
    // UE matches if any of its DRBs matches
    for (int l = 0; l < sched_ctrl->dl_lc_num; ++l) {
      long lcid = sched_ctrl->dl_lc_ids[l];
      if (nssai_matches(sched_ctrl->dl_lc_nssai[lcid], sst, sd)) {
        matches->ue_list[i++] = ue;
        break;
      }
    }
    AssertFatal(i < MAX_MOBILES_PER_GNB, "cannot have more UEs than global UE number maximum\n");
  }

  matches->num_ues = i;

  return i;
}

static nr_rlc_statistics_t get_rlc_stats_per_drb(NR_UE_info_t const * UE)
{
  assert(UE != NULL);

  nr_rlc_statistics_t rlc = {0};
  const int srb_flag = 0;
  const int rb_id = 1;  // at the moment, only 1 DRB is supported

  // Get RLC stats for specific DRB
  const bool rc = nr_rlc_get_statistics(UE->rnti, srb_flag, rb_id, &rlc);
  assert(rc == true && "Cannot get RLC stats\n");

  // Activate average sojourn time at the RLC buffer for specific DRB
  nr_rlc_activate_avg_time_to_tx(UE->rnti, rb_id+3, 1);
  
  return rlc;  
}

static meas_record_lst_t fill_ue_mac_rlc_data(const NR_UE_info_t* UE, const size_t ue_idx, const char * meas_info_name_str, const uint32_t gran_period_ms)
{
  assert(UE != NULL);

  meas_record_lst_t meas_record = {0};

  // Get RLC stats per DRB
  nr_rlc_statistics_t rlc = get_rlc_stats_per_drb(UE);

  // Measurement Type as requested in Action Definition
  if (strcmp(meas_info_name_str, "DRB.UEThpDl") == 0) { //  3GPP TS 28.522 - section 5.1.1.3.1
    meas_record.value = REAL_MEAS_VALUE;

    // Calculate DL Thp
    meas_record.real_val = (double)(rlc.txpdu_bytes - last_rlc_pdu_total_bytes[ue_idx].dl)*8/gran_period_ms;  // [kbps]
    last_rlc_pdu_total_bytes[ue_idx].dl = rlc.txpdu_bytes;
    /*  note: per spec, average UE throughput in DL (taken into consideration values from all UEs, and averaged)
        here calculated as: UE specific throughput in DL */
  } else if (strcmp(meas_info_name_str, "DRB.UEThpUl") == 0) {  //  3GPP TS 28.522 - section 5.1.1.3.3
    meas_record.value = REAL_MEAS_VALUE;

    // Calculate UL Thp
    meas_record.real_val = (double)(rlc.rxpdu_bytes - last_rlc_pdu_total_bytes[ue_idx].ul)*8/gran_period_ms;  // [kbps]
    last_rlc_pdu_total_bytes[ue_idx].ul = rlc.rxpdu_bytes;
    /*  note: per spec, average UE throughput in UL (taken into consideration values from all UEs, and averaged)
        here calculated as: UE specific throughput in UL */
  } else if (strcmp(meas_info_name_str, "DRB.RlcSduDelayDl") == 0) {  //  3GPP TS 28.522 - section 5.1.3.3.3
    meas_record.value = REAL_MEAS_VALUE;

    // Get the value of sojourn time at the RLC buffer
    meas_record.real_val = rlc.txsdu_avg_time_to_tx;  // [μs]
    /* note: by default this measurement is calculated for previous 100ms (openair2/LAYER2/nr_rlc/nr_rlc_entity.c:118, 173, 213); please, update according to your needs */
  } else if (strcmp(meas_info_name_str, "RRU.PrbTotDl") == 0) {  //  3GPP TS 28.522 - section 5.1.1.2.1
    meas_record.value = INTEGER_MEAS_VALUE;

    // Get the number of DL PRBs
    meas_record.int_val = UE->mac_stats.dl.total_rbs - last_total_prbs[ue_idx].dl;   // [PRBs]
    last_total_prbs[ue_idx].dl = UE->mac_stats.dl.total_rbs;
    /*  note: per spec, DL PRB usage [%] = (total used PRBs for DL traffic / total available PRBs for DL traffic) * 100   
        here calculated as: aggregated DL PRBs (t) - aggregated DL PRBs (t-gran_period) */
  } else if (strcmp(meas_info_name_str, "RRU.PrbTotUl") == 0) {  //  3GPP TS 28.522 - section 5.1.1.2.2
    meas_record.value = INTEGER_MEAS_VALUE;

    // Get the number of UL PRBs
    meas_record.int_val = UE->mac_stats.ul.total_rbs - last_total_prbs[ue_idx].ul;   // [PRBs]
    last_total_prbs[ue_idx].ul = UE->mac_stats.ul.total_rbs;
    /*  note: per spec, UL PRB usage [%] = (total used PRBs for UL traffic / total available PRBs for UL traffic) * 100   
        here calculated as: aggregated UL PRBs (t) - aggregated UL PRBs (t-gran_period) */
  } else {
    assert(false && "Measurement Name not yet implemented");
  }

  return meas_record;
}

static kpm_ind_msg_format_1_t fill_kpm_ind_msg_frm_1_in_du(const NR_UE_info_t* UE, const size_t ue_idx,  const kpm_act_def_format_1_t * act_def_fr_1)
{
  kpm_ind_msg_format_1_t msg_frm_1 = {0};
  
  // Measurement Data contains a set of Meas Records, each collected at each granularity period
  msg_frm_1.meas_data_lst_len = 1;  /*  this value is equal to (kpm_ric_event_trigger_format_1.report_period_ms/act_def_fr_1->gran_period_ms)
                                        please, check their values in xApp */
  
  msg_frm_1.meas_data_lst = calloc(msg_frm_1.meas_data_lst_len, sizeof(*msg_frm_1.meas_data_lst));
  assert(msg_frm_1.meas_data_lst != NULL && "Memory exhausted" );

  for (size_t i = 0; i<msg_frm_1.meas_data_lst_len; i++) {
    // Measurement Record
    msg_frm_1.meas_data_lst[i].meas_record_len = act_def_fr_1->meas_info_lst_len;  // record data list length corresponds to info list length from action definition

    msg_frm_1.meas_data_lst[i].meas_record_lst = calloc(msg_frm_1.meas_data_lst[i].meas_record_len, sizeof(meas_record_lst_t));
    assert(msg_frm_1.meas_data_lst[i].meas_record_lst != NULL && "Memory exhausted");

    for (size_t j = 0; j < msg_frm_1.meas_data_lst[i].meas_record_len; j++) { // each meas record corresponds to one meas type
      // Measurement Type as requested in Action Definition
      switch (act_def_fr_1->meas_info_lst[j].meas_type.type) {
      case NAME_MEAS_TYPE: {
        char meas_info_name_str[act_def_fr_1->meas_info_lst[j].meas_type.name.len + 1];
        memcpy(meas_info_name_str, act_def_fr_1->meas_info_lst[j].meas_type.name.buf, act_def_fr_1->meas_info_lst[j].meas_type.name.len);
        meas_info_name_str[act_def_fr_1->meas_info_lst[j].meas_type.name.len] = '\0';

        msg_frm_1.meas_data_lst[i].meas_record_lst[j] = fill_ue_mac_rlc_data(UE, ue_idx, meas_info_name_str, act_def_fr_1->gran_period_ms);
        break;
      }
      case ID_MEAS_TYPE:
        assert(false && "ID Measurement Type not yet implemented");
      
      default:
        assert(false && "Measurement Type not recognized");
      }
    }
  }

  // Measurement Information - OPTIONAL
  msg_frm_1.meas_info_lst_len = act_def_fr_1->meas_info_lst_len;
  msg_frm_1.meas_info_lst = calloc(msg_frm_1.meas_info_lst_len, sizeof(meas_info_format_1_lst_t));
  assert(msg_frm_1.meas_info_lst != NULL && "Memory exhausted");
  for (size_t i = 0; i < msg_frm_1.meas_info_lst_len; i++) {
    msg_frm_1.meas_info_lst[i] = cp_meas_info_format_1_lst(&act_def_fr_1->meas_info_lst[i]);
  }

  return msg_frm_1;
}

static kpm_ind_msg_format_3_t fill_kpm_ind_msg_frm_3_in_du(const matched_ues_mac_t* matched_ues,
                                                           const kpm_act_def_format_1_t* act_def_fr_1)
{
  assert(act_def_fr_1 != NULL);


  kpm_ind_msg_format_3_t msg_frm_3 = {0};

  // Fill UE Measurement Reports

  msg_frm_3.ue_meas_report_lst_len = matched_ues->num_ues;
  msg_frm_3.meas_report_per_ue = calloc(msg_frm_3.ue_meas_report_lst_len, sizeof(meas_report_per_ue_t));
  assert(msg_frm_3.meas_report_per_ue != NULL && "Memory exhausted");

  for (size_t i = 0; i<msg_frm_3.ue_meas_report_lst_len; i++) {
    // Fill UE ID data
    f1_ue_data_t rrc_ue_id = du_get_f1_ue_data(matched_ues->ue_list[i]->rnti); // get gNB CU UE ID as rrc_ue_id
    msg_frm_3.meas_report_per_ue[i].ue_meas_report_lst.type = GNB_DU_UE_ID_E2SM;
    msg_frm_3.meas_report_per_ue[i].ue_meas_report_lst.gnb_du = fill_gnb_du_data(&rrc_ue_id);
      
    // Fill UE related info
    msg_frm_3.meas_report_per_ue[i].ind_msg_format_1 = fill_kpm_ind_msg_frm_1_in_du(matched_ues->ue_list[i], i, act_def_fr_1);
  }


  return msg_frm_3;
}

static kpm_ind_msg_format_1_t fill_kpm_ind_msg_frm_1_in_monolithic(const NR_UE_info_t* UE, const size_t ue_idx, const uint32_t rrc_ue_id, const kpm_act_def_format_1_t * act_def_fr_1)
{
  kpm_ind_msg_format_1_t msg_frm_1 = {0};
  
  // Measurement Data contains a set of Meas Records, each collected at each granularity period
  msg_frm_1.meas_data_lst_len = 1;  /*  this value is equal to (kpm_ric_event_trigger_format_1.report_period_ms/act_def_fr_1->gran_period_ms)
                                        please, check their values in xApp */
  
  msg_frm_1.meas_data_lst = calloc(msg_frm_1.meas_data_lst_len, sizeof(*msg_frm_1.meas_data_lst));
  assert(msg_frm_1.meas_data_lst != NULL && "Memory exhausted" );

  for (size_t i = 0; i<msg_frm_1.meas_data_lst_len; i++) {
    // Measurement Record
    msg_frm_1.meas_data_lst[i].meas_record_len = act_def_fr_1->meas_info_lst_len;  // record data list length corresponds to info list length from action definition

    msg_frm_1.meas_data_lst[i].meas_record_lst = calloc(msg_frm_1.meas_data_lst[i].meas_record_len, sizeof(meas_record_lst_t));
    assert(msg_frm_1.meas_data_lst[i].meas_record_lst != NULL && "Memory exhausted");

    for (size_t j = 0; j < msg_frm_1.meas_data_lst[i].meas_record_len; j++) { // each meas record corresponds to one meas type
      // Measurement Type as requested in Action Definition
      switch (act_def_fr_1->meas_info_lst[j].meas_type.type) {
      case NAME_MEAS_TYPE: {
        char meas_info_name_str[act_def_fr_1->meas_info_lst[j].meas_type.name.len + 1];
        memcpy(meas_info_name_str, act_def_fr_1->meas_info_lst[j].meas_type.name.buf, act_def_fr_1->meas_info_lst[j].meas_type.name.len);
        meas_info_name_str[act_def_fr_1->meas_info_lst[j].meas_type.name.len] = '\0';

        if (strcmp(meas_info_name_str, "DRB.PdcpSduVolumeDL") == 0 || strcmp(meas_info_name_str, "DRB.PdcpSduVolumeUL") == 0) {
          msg_frm_1.meas_data_lst[i].meas_record_lst[j] = fill_ue_pdcp_data(rrc_ue_id, ue_idx, meas_info_name_str);
        } else {
          msg_frm_1.meas_data_lst[i].meas_record_lst[j] = fill_ue_mac_rlc_data(UE, ue_idx, meas_info_name_str, act_def_fr_1->gran_period_ms);
        }
        
        break;
      }
      case ID_MEAS_TYPE:
        assert(false && "ID Measurement Type not yet implemented");

      default:
        assert(false && "Measurement Type not recognized");
      }
    }
  }

  // Measurement Information - OPTIONAL
  msg_frm_1.meas_info_lst_len = act_def_fr_1->meas_info_lst_len;
  msg_frm_1.meas_info_lst = calloc(msg_frm_1.meas_info_lst_len, sizeof(meas_info_format_1_lst_t));
  assert(msg_frm_1.meas_info_lst != NULL && "Memory exhausted");
  for (size_t i = 0; i < msg_frm_1.meas_info_lst_len; i++) {
    msg_frm_1.meas_info_lst[i] = cp_meas_info_format_1_lst(&act_def_fr_1->meas_info_lst[i]);
  }

  return msg_frm_1;
}

static kpm_ind_msg_format_3_t fill_kpm_ind_msg_frm_3_in_monolithic(const matched_ues_mac_t* matched_ues,
                                                                   const kpm_act_def_format_1_t* act_def_fr_1)
{
  assert(act_def_fr_1 != NULL);


  kpm_ind_msg_format_3_t msg_frm_3 = {0};

  // Fill UE Measurement Reports

  msg_frm_3.ue_meas_report_lst_len = matched_ues->num_ues;
  msg_frm_3.meas_report_per_ue = calloc(msg_frm_3.ue_meas_report_lst_len, sizeof(meas_report_per_ue_t));
  assert(msg_frm_3.meas_report_per_ue != NULL && "Memory exhausted");


  for (size_t i = 0; i<msg_frm_3.ue_meas_report_lst_len; i++) {
    // Fill UE ID data
    rrc_gNB_ue_context_t* rrc_ue_context_list = rrc_gNB_get_ue_context_by_rnti_any_du(RC.nrrrc[0], matched_ues->ue_list[i]->rnti);
    msg_frm_3.meas_report_per_ue[i].ue_meas_report_lst.type = GNB_UE_ID_E2SM;
    msg_frm_3.meas_report_per_ue[i].ue_meas_report_lst.gnb = fill_gnb_data(rrc_ue_context_list);
      
    // Fill UE related info
    msg_frm_3.meas_report_per_ue[i].ind_msg_format_1 =
        fill_kpm_ind_msg_frm_1_in_monolithic(matched_ues->ue_list[i], i, rrc_ue_context_list->ue_context.rrc_ue_id, act_def_fr_1);
  }

  return msg_frm_3;
}
#endif

#if defined (NGRAN_GNB_CUCP)
typedef struct {
  uint32_t rrc_ue_id_list[MAX_MOBILES_PER_GNB]; // list of matched UEs on RRC level containing only rrc_ue_id (gNB CU UE ID)
  size_t num_ues;

} matched_ues_rrc_t;

static size_t filter_ues_by_s_nssai_in_cu(test_cond_e const condition, uint8_t sst, const uint32_t *sd, matched_ues_rrc_t* matches)
{
  DevAssert(matches != NULL);
  AssertFatal(condition == EQUAL_TEST_COND, "Condition %d not yet implemented\n", condition);

  struct rrc_gNB_ue_context_s *ue_context_p1 = NULL;
  size_t i = 0;
  RB_FOREACH(ue_context_p1, rrc_nr_ue_tree_s, &RC.nrrrc[0]->rrc_ue_head) {
    gNB_RRC_UE_t *ue = &ue_context_p1->ue_context;
    for (int p = 0; p < ue->nb_of_pdusessions; ++p) {
      pdusession_t *pdu = &ue->pduSession[0].param;
      if (nssai_matches(pdu->nssai, sst, sd)) {
        matches->rrc_ue_id_list[i++] = ue_context_p1->ue_context.rrc_ue_id;
        break;
      }
    }
    AssertFatal(i < MAX_MOBILES_PER_GNB, "cannot have more UEs than global UE number maximum\n");
  }

  matches->num_ues = i;
  
  return i;
}

static kpm_ind_msg_format_3_t fill_kpm_ind_msg_frm_3_in_cu(const matched_ues_rrc_t* matched_ues,
                                                           const kpm_act_def_format_1_t* act_def_fr_1)
{
  assert(act_def_fr_1 != NULL);


  kpm_ind_msg_format_3_t msg_frm_3 = {0};

  // Fill UE Measurement Reports

  msg_frm_3.ue_meas_report_lst_len = matched_ues->num_ues;
  msg_frm_3.meas_report_per_ue = calloc(msg_frm_3.ue_meas_report_lst_len, sizeof(meas_report_per_ue_t));
  assert(msg_frm_3.meas_report_per_ue != NULL && "Memory exhausted");

  for (size_t i = 0; i<msg_frm_3.ue_meas_report_lst_len; i++) {
    // Fill UE ID data
    rrc_gNB_ue_context_t* rrc_ue_context_list = rrc_gNB_get_ue_context(RC.nrrrc[0], matched_ues->rrc_ue_id_list[i]);
    msg_frm_3.meas_report_per_ue[i].ue_meas_report_lst.type = GNB_UE_ID_E2SM;
    msg_frm_3.meas_report_per_ue[i].ue_meas_report_lst.gnb = fill_gnb_data(rrc_ue_context_list);

    // Fill UE related info
    msg_frm_3.meas_report_per_ue[i].ind_msg_format_1 =
        fill_kpm_ind_msg_frm_1_in_cu(matched_ues->rrc_ue_id_list[i], i, act_def_fr_1);
  }

  return msg_frm_3;
}
#endif

static kpm_ric_ind_hdr_format_1_t kpm_ind_hdr_frm_1(void)
{
  kpm_ric_ind_hdr_format_1_t hdr_frm_1 = {0};

  int64_t const t = time_now_us();
#if defined KPM_V2_03
  hdr_frm_1.collectStartTime = t/1000000; // seconds
#elif defined KPM_V3_00 
  hdr_frm_1.collectStartTime = t; // microseconds
#else
  static_assert(0!=0, "Undefined KPM SM Version");
#endif

  hdr_frm_1.fileformat_version = NULL;

  // Check E2 Node NG-RAN Type
  #if defined (NGRAN_GNB_DU)
  if (RC.nrrrc[0]->node_type == ngran_gNB_DU) {
    hdr_frm_1.sender_name = calloc(1, sizeof(byte_array_t));
    hdr_frm_1.sender_name->buf = calloc(strlen("OAI-DU") + 1, sizeof(char));
    memcpy(hdr_frm_1.sender_name->buf, "OAI-DU", strlen("OAI-DU"));
    hdr_frm_1.sender_name->len = strlen("OAI-DU");

    hdr_frm_1.sender_type = calloc(1, sizeof(byte_array_t));
    hdr_frm_1.sender_type->buf = calloc(strlen("DU") + 1, sizeof(char));
    memcpy(hdr_frm_1.sender_type->buf, "DU", strlen("DU"));
    hdr_frm_1.sender_type->len = strlen("DU");
  } else if (RC.nrrrc[0]->node_type == ngran_gNB_CU) {
    hdr_frm_1.sender_name = calloc(1, sizeof(byte_array_t));
    hdr_frm_1.sender_name->buf = calloc(strlen("OAI-CU") + 1, sizeof(char));
    memcpy(hdr_frm_1.sender_name->buf, "OAI-CU", strlen("OAI-CU"));
    hdr_frm_1.sender_name->len = strlen("OAI-CU");

    hdr_frm_1.sender_type = calloc(1, sizeof(byte_array_t));
    hdr_frm_1.sender_type->buf = calloc(strlen("CU") + 1, sizeof(char));
    memcpy(hdr_frm_1.sender_type->buf, "CU", strlen("CU"));
    hdr_frm_1.sender_type->len = strlen("CU");
  } else if (RC.nrrrc[0]->node_type == ngran_gNB) {
    hdr_frm_1.sender_name = calloc(1, sizeof(byte_array_t));
    hdr_frm_1.sender_name->buf = calloc(strlen("OAI-MONO") + 1, sizeof(char));
    memcpy(hdr_frm_1.sender_name->buf, "OAI-MONO", strlen("OAI-MONO"));
    hdr_frm_1.sender_name->len = strlen("OAI-MONO");

    hdr_frm_1.sender_type = calloc(1, sizeof(byte_array_t));
    hdr_frm_1.sender_type->buf = calloc(strlen("MONO") + 1, sizeof(char));
    memcpy(hdr_frm_1.sender_type->buf, "MONO", strlen("MONO"));
    hdr_frm_1.sender_type->len = strlen("MONO");
  } else if (RC.nrrrc[0]->node_type == ngran_gNB_CUCP) {
    return hdr_frm_1;  // nothing to fill
  } else {
    assert(0!=0 && "Unknown node type");
  }
  #endif

  #if defined (NGRAN_GNB_CUUP)
  hdr_frm_1.sender_name = calloc(1, sizeof(byte_array_t));
  hdr_frm_1.sender_name->buf = calloc(strlen("OAI-CU-UP") + 1, sizeof(char));
  memcpy(hdr_frm_1.sender_name->buf, "OAI-CU-UP", strlen("OAI-CU-UP"));
  hdr_frm_1.sender_name->len = strlen("OAI-CU-UP");

  hdr_frm_1.sender_type = calloc(1, sizeof(byte_array_t));
  hdr_frm_1.sender_type->buf = calloc(strlen("CU-UP") + 1, sizeof(char));
  memcpy(hdr_frm_1.sender_type->buf, "CU-UP", strlen("CU-UP"));
  hdr_frm_1.sender_type->len = strlen("CU-UP");
  #endif

  hdr_frm_1.vendor_name = calloc(1, sizeof(byte_array_t));
  hdr_frm_1.vendor_name->buf = calloc(strlen("OAI") + 1, sizeof(char));
  memcpy(hdr_frm_1.vendor_name->buf, "OAI", strlen("OAI"));
  hdr_frm_1.vendor_name->len = strlen("OAI");

  return hdr_frm_1;
}

kpm_ind_hdr_t kpm_ind_hdr(void)
{
  kpm_ind_hdr_t hdr = {0};

  hdr.type = FORMAT_1_INDICATION_HEADER;
  hdr.kpm_ric_ind_hdr_format_1 = kpm_ind_hdr_frm_1();

  return hdr;
}

static void capture_sst_sd(test_info_lst_t* test, uint8_t *sst, uint32_t **sd)
{
  DevAssert(test != NULL && test->test_cond_value != NULL);
  DevAssert(sst != NULL);
  DevAssert(sd != NULL);

  // we made a mistake in the past: NSSAI is supposed to be an OCTET_STRING,
  // but earlier version of the RAN function and the xApp used integer, so
  // handle this gracefully by accepting integer as well
  switch (test->test_cond_value->type) {
    case INTEGER_TEST_COND_VALUE: {
      AssertFatal(*test->test_cond_value->int_value <= 0xff, "illegal SST %ld\n", *test->test_cond_value->int_value);
      *sst = *test->test_cond_value->int_value;
      *sd = NULL;
      break;
    }
    case OCTET_STRING_TEST_COND_VALUE: {
      if (test->test_cond_value->octet_string_value->len == 1) {
        *sst = test->test_cond_value->octet_string_value->buf[0];
        *sd = NULL;
      } else {
        DevAssert(test->test_cond_value->octet_string_value->len == 4);
        uint8_t *buf = test->test_cond_value->octet_string_value->buf;
        *sst = buf[0];
        *sd = malloc(**sd);
        **sd = buf[1] << 16 | buf[2] << 8 | buf[3];
      }
      break;
    }
    default:
      AssertFatal(false, "test condition value %d impossible\n", test->test_cond_value->type);
  }
}

bool read_kpm_sm(void* data)
{
  assert(data != NULL);
  // assert(data->type == KPM_STATS_V3_0);

  kpm_rd_ind_data_t* const kpm = (kpm_rd_ind_data_t*)data;

  assert(kpm->act_def != NULL && "Cannot be NULL");

  // 7.8 Supported RIC Styles and E2SM IE Formats
  // Action Definition Format 4 corresponds to Indication Message Format 3
  switch (kpm->act_def->type) {
    case FORMAT_4_ACTION_DEFINITION: {
      kpm->ind.hdr = kpm_ind_hdr();

      kpm->ind.msg.type = FORMAT_3_INDICATION_MESSAGE;
      // Filter the UE by the test condition criteria
      kpm_act_def_format_4_t const* frm_4 = &kpm->act_def->frm_4; // 8.2.1.2.4
      for (size_t i = 0; i < frm_4->matching_cond_lst_len; i++) {
        switch (frm_4->matching_cond_lst[i].test_info_lst.test_cond_type) {
          case GBR_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }
          case AMBR_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }
          case IsStat_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }
          case IsCatM_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }

          case DL_RSRP_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }

          case DL_RSRQ_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }

          case UL_RSRP_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }

          case CQI_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }

          case fiveQI_TEST_COND_TYPE: {
            assert(0 != 0 && "Not implemented");
            break;
          }

          case QCI_TEST_COND_TYPE: {
            ;
            assert(0 != 0 && "Not implemented");
            break;
          }
          case S_NSSAI_TEST_COND_TYPE: {
            assert(frm_4->matching_cond_lst[i].test_info_lst.S_NSSAI == TRUE_TEST_COND_TYPE && "Must be true");
            assert(frm_4->matching_cond_lst[i].test_info_lst.test_cond != NULL && "Even though is optional..");
            assert(frm_4->matching_cond_lst[i].test_info_lst.test_cond_value != NULL && "Even though is optional..");

            test_cond_e const test_cond = *frm_4->matching_cond_lst[i].test_info_lst.test_cond;
            uint8_t sst = 0;
            uint32_t *sd = NULL;
            capture_sst_sd(&frm_4->matching_cond_lst[i].test_info_lst, &sst, &sd);
            // Check E2 Node NG-RAN Type
            /* Current implementation:
                - we only have one executable nr-softmodem for 4 node types: DU, CU, gNB-mono, CU-CP
               In the future, when nr-softmodem is separated, linking should be done as following:
                 DU: e2_ran_func_du
                 CU-CP : e2_ran_func_cucp
                 CU-UP: e2_ran_func_cuup (this is available at the moment, executable nr-cuup)
                 CU: e2_ran_func_cucp + e2_ran_func_cuup
                 gNB-mono: e2_ran_func_du + e2_ran_func_cucp + e2_ran_func_cuup */
            #if defined (NGRAN_GNB_DU)
            if (RC.nrrrc[0]->node_type == ngran_gNB_DU) {
              matched_ues_mac_t matched_ues = {0};
              matched_ues.num_ues = filter_ues_by_s_nssai_in_du_or_monolithic(test_cond, sst, sd, &matched_ues);
              if (matched_ues.num_ues == 0) return false;
              kpm->ind.msg.frm_3 = fill_kpm_ind_msg_frm_3_in_du(&matched_ues, &frm_4->action_def_format_1);
            } else if (RC.nrrrc[0]->node_type == ngran_gNB_CU) {
              matched_ues_rrc_t matched_ues = {0};
              matched_ues.num_ues = filter_ues_by_s_nssai_in_cu(test_cond, sst, sd, &matched_ues);
              if (matched_ues.num_ues == 0) return false;
              kpm->ind.msg.frm_3 = fill_kpm_ind_msg_frm_3_in_cu(&matched_ues, &frm_4->action_def_format_1);
            } else if (RC.nrrrc[0]->node_type == ngran_gNB) {
              matched_ues_mac_t matched_ues = {0};
              matched_ues.num_ues = filter_ues_by_s_nssai_in_du_or_monolithic(test_cond, sst, sd, &matched_ues);
              if (matched_ues.num_ues == 0) return false;
              kpm->ind.msg.frm_3 = fill_kpm_ind_msg_frm_3_in_monolithic(&matched_ues, &frm_4->action_def_format_1);
            } else if (RC.nrrrc[0]->node_type == ngran_gNB_CUCP) {
              return false;  // at the moment, measurements regarding CU-CP node are not yet implemented
            } else {
              assert(false && "NG-RAN Type not implemented");
            }
            

            #elif defined (NGRAN_GNB_CUUP)
            matched_ues_pdcp_t matched_ues = {0};
            matched_ues.num_ues = filter_ues_by_s_nssai_in_cuup(test_cond, sst, sd, &matched_ues);
            if (matched_ues.num_ues == 0) return false;
            kpm->ind.msg.frm_3 = fill_kpm_ind_msg_frm_3_in_cuup(&matched_ues, &frm_4->action_def_format_1);
            #endif
            
            
            free(sd); // if NULL, nothing happens

            break;
          }

          default:
            assert(false && "Unknown Test condition");
        }
      }

      break;
    }

    default: {
      AssertFatal(kpm->act_def->type == FORMAT_4_ACTION_DEFINITION, "Action Definition Format %d not yet implemented", kpm->act_def->type);
    }
  }
  
  return true;
}

void read_kpm_setup_sm(void* e2ap)
{
  assert(e2ap != NULL);
//  assert(e2ap->type == KPM_V3_0_AGENT_IF_E2_SETUP_ANS_V0);

  kpm_e2_setup_t* kpm = (kpm_e2_setup_t*)(e2ap);
  kpm->ran_func_def = fill_rnd_kpm_ran_func_def(); 
}

sm_ag_if_ans_t write_ctrl_kpm_sm(void const* src)
{
  assert(0 !=0 && "Not supported");
  (void)src;
  sm_ag_if_ans_t ans = {0};
  return ans;
}