/*
 * 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 gNB_scheduler_bch.c
 * \brief procedures related to gNB for the BCH transport channel
 * \author  Navid Nikaein and Raymond Knopp, WEI-TAI CHEN
 * \date 2010 - 2014, 2018
 * \email: navid.nikaein@eurecom.fr, kroempa@gmail.com
 * \version 1.0
 * \company Eurecom, NTUST
 * @ingroup _mac

 */

#include "assertions.h"
#include "NR_MAC_gNB/nr_mac_gNB.h"
#include "NR_MAC_gNB/mac_proto.h"
#include "NR_MAC_COMMON/nr_mac_extern.h"
#include "common/utils/LOG/log.h"
#include "common/utils/LOG/vcd_signal_dumper.h"
#include "UTIL/OPT/opt.h"
#include "common/utils/nr/nr_common.h"
#include "openair1/PHY/defs_nr_common.h"


#define ENABLE_MAC_PAYLOAD_DEBUG

#include "common/ran_context.h"

#include "executables/softmodem-common.h"

extern RAN_CONTEXT_t RC;

static void schedule_ssb(frame_t frame,
                         sub_frame_t slot,
                         NR_ServingCellConfigCommon_t *scc,
                         nfapi_nr_dl_tti_request_body_t *dl_req,
                         int i_ssb,
                         uint8_t scoffset,
                         uint16_t offset_pointa,
                         uint32_t payload)
{
  uint8_t beam_index = 0;
  nfapi_nr_dl_tti_request_pdu_t  *dl_config_pdu = &dl_req->dl_tti_pdu_list[dl_req->nPDUs];
  memset((void *) dl_config_pdu, 0,sizeof(nfapi_nr_dl_tti_request_pdu_t));
  dl_config_pdu->PDUType      = NFAPI_NR_DL_TTI_SSB_PDU_TYPE;
  dl_config_pdu->PDUSize      =2 + sizeof(nfapi_nr_dl_tti_ssb_pdu_rel15_t);

  AssertFatal(scc->physCellId!=NULL,"ServingCellConfigCommon->physCellId is null\n");
  AssertFatal(*scc->physCellId < 1008 && *scc->physCellId >=0, "5G physicall cell id out of range: %ld\n", *scc->physCellId); 
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.PhysCellId          = *scc->physCellId;
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.BetaPss             = 0;
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.SsbBlockIndex       = i_ssb;
  AssertFatal(scc->downlinkConfigCommon!=NULL,"scc->downlinkConfigCommonL is null\n");
  AssertFatal(scc->downlinkConfigCommon->frequencyInfoDL!=NULL,"scc->downlinkConfigCommon->frequencyInfoDL is null\n");
  AssertFatal(scc->downlinkConfigCommon->frequencyInfoDL->absoluteFrequencySSB!=NULL,"scc->downlinkConfigCommon->frequencyInfoDL->absoluteFrequencySSB is null\n");
  AssertFatal(scc->downlinkConfigCommon->frequencyInfoDL->frequencyBandList.list.count==1,"Frequency Band list does not have 1 element (%d)\n",
              scc->downlinkConfigCommon->frequencyInfoDL->frequencyBandList.list.count);
  AssertFatal(scc->ssbSubcarrierSpacing,"ssbSubcarrierSpacing is null\n");
  AssertFatal(scc->downlinkConfigCommon->frequencyInfoDL->frequencyBandList.list.array[0],"band is null\n");

  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.SsbSubcarrierOffset = scoffset; //kSSB
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.ssbOffsetPointA     = offset_pointa;
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.bchPayloadFlag      = 1;
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.bchPayload          = payload;
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.precoding_and_beamforming.num_prgs=1;
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.precoding_and_beamforming.prg_size=275; //1 PRG of max size for analogue beamforming
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.precoding_and_beamforming.dig_bf_interfaces=1;
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.precoding_and_beamforming.prgs_list[0].pm_idx = 0;
  dl_config_pdu->ssb_pdu.ssb_pdu_rel15.precoding_and_beamforming.prgs_list[0].dig_bf_interface_list[0].beam_idx = beam_index;
  dl_req->nPDUs++;

  LOG_D(MAC,"Scheduling ssb %d at frame %d and slot %d\n",i_ssb,frame,slot);
}

static void fill_ssb_vrb_map(NR_COMMON_channels_t *cc, int rbStart, int ssb_subcarrier_offset, uint16_t symStart, int CC_id)
{
  AssertFatal(*cc->ServingCellConfigCommon->ssbSubcarrierSpacing !=
              NR_SubcarrierSpacing_kHz240,
              "240kHZ subcarrier won't work with current VRB map because a single SSB might be across 2 slots\n");

  uint16_t *vrb_map = cc[CC_id].vrb_map;
  const int extra_prb = ssb_subcarrier_offset > 0;
  for (int rb = 0; rb < 20 + extra_prb; rb++)
    vrb_map[rbStart + rb] = SL_to_bitmap(symStart % NR_SYMBOLS_PER_SLOT, 4);
}

static int encode_mib(NR_BCCH_BCH_Message_t *mib, frame_t frame, uint8_t *buffer, int buf_size)
{
  int encode_size = 3;
  AssertFatal(buf_size >= encode_size, "buffer of size %d too small, need 3 bytes\n", buf_size);
  int encoded = encode_MIB_NR(mib, frame, buffer, encode_size);
  DevAssert(encoded == encode_size);
  return encode_size;
}

void schedule_nr_mib(module_id_t module_idP, frame_t frameP, sub_frame_t slotP, nfapi_nr_dl_tti_request_t *DL_req)
{
  gNB_MAC_INST *gNB = RC.nrmac[module_idP];
  /* already mutex protected: held in gNB_dlsch_ulsch_scheduler() */
  nfapi_nr_dl_tti_request_body_t *dl_req;
  uint8_t num_tdd_period,num_ssb;
  int CC_id;

  for (CC_id = 0; CC_id < MAX_NUM_CCs; CC_id++) {
    NR_COMMON_channels_t *cc= &gNB->common_channels[CC_id];
    const NR_MIB_t *mib = cc->mib->message.choice.mib;
    NR_ServingCellConfigCommon_t *scc = cc->ServingCellConfigCommon;
    const int slots_per_frame = nr_slots_per_frame[*scc->ssbSubcarrierSpacing];
    dl_req = &DL_req->dl_tti_request_body;

    // get MIB every 8 frames
    if(((slotP == 0) && (frameP & 7) == 0) ||
       gNB->first_MIB) {
      int mib_sdu_length = encode_mib(cc->mib, frameP, cc->MIB_pdu, sizeof(cc->MIB_pdu));

      // flag to avoid sending an empty MIB in the first frames of execution since gNB doesn't get at the beginning in frame 0 slot 0
      gNB->first_MIB = false;

      LOG_D(MAC,
            "[gNB %d] Frame %d : MIB->BCH  CC_id %d, Received %d bytes\n",
            module_idP,
            frameP,
            CC_id,
            mib_sdu_length);
    }

    uint32_t mib_pdu = (*(uint32_t *)cc->MIB_pdu) & ((1 << 24) - 1);

    int8_t ssb_period = *scc->ssb_periodicityServingCell;
    uint8_t ssb_frame_periodicity = 1;  // every how many frames SSB are generated

    if (ssb_period > 1) // 0 is every half frame
      ssb_frame_periodicity = 1 << (ssb_period -1);

    if (!(frameP%ssb_frame_periodicity) &&
        ((slotP<(slots_per_frame>>1)) || (ssb_period == 0))) {
      // schedule SSB only for given frames according to SSB periodicity
      // and in first half frame unless periodicity of 5ms
      int rel_slot;
      if (ssb_period == 0) // scheduling every half frame
        rel_slot = slotP%(slots_per_frame>>1);
      else
        rel_slot = slotP;

      NR_SubcarrierSpacing_t scs = *scc->ssbSubcarrierSpacing;
      const long band = *scc->downlinkConfigCommon->frequencyInfoDL->frequencyBandList.list.array[0];
      const uint16_t offset_pointa = gNB->ssb_OffsetPointA;
      uint8_t ssbSubcarrierOffset = gNB->ssb_SubcarrierOffset;

      const BIT_STRING_t *shortBitmap = &scc->ssb_PositionsInBurst->choice.shortBitmap;
      const BIT_STRING_t *mediumBitmap = &scc->ssb_PositionsInBurst->choice.mediumBitmap;
      const BIT_STRING_t *longBitmap = &scc->ssb_PositionsInBurst->choice.longBitmap;

      uint16_t ssb_start_symbol;

      switch (scc->ssb_PositionsInBurst->present) {
        case 1:
          // short bitmap (<3GHz) max 4 SSBs
          for (int i_ssb=0; i_ssb<4; i_ssb++) {
            if ((shortBitmap->buf[0]>>(7-i_ssb))&0x01) {
              ssb_start_symbol = get_ssb_start_symbol(band,scs,i_ssb);
              // if start symbol is in current slot, schedule current SSB, fill VRB map and call get_type0_PDCCH_CSS_config_parameters
              if ((ssb_start_symbol/14) == rel_slot){
                const int prb_offset = offset_pointa >> scs;
                schedule_ssb(frameP, slotP, scc, dl_req, i_ssb, ssbSubcarrierOffset, offset_pointa, mib_pdu);
                fill_ssb_vrb_map(cc, prb_offset, ssbSubcarrierOffset, ssb_start_symbol, CC_id);
                if (get_softmodem_params()->sa == 1) {
                  get_type0_PDCCH_CSS_config_parameters(&gNB->type0_PDCCH_CSS_config[i_ssb],
                                                        frameP,
                                                        mib,
                                                        slots_per_frame,
                                                        ssbSubcarrierOffset,
                                                        ssb_start_symbol,
                                                        scs,
                                                        FR1,
                                                        band,
                                                        i_ssb,
                                                        ssb_frame_periodicity,
                                                        prb_offset);
                  gNB->type0_PDCCH_CSS_config[i_ssb].active = true;
                }
              }
            }
          }
          break;
        case 2:
          // medium bitmap (<6GHz) max 8 SSBs
          for (int i_ssb=0; i_ssb<8; i_ssb++) {
            if ((mediumBitmap->buf[0]>>(7-i_ssb))&0x01) {
              ssb_start_symbol = get_ssb_start_symbol(band,scs,i_ssb);
              // if start symbol is in current slot, schedule current SSB, fill VRB map and call get_type0_PDCCH_CSS_config_parameters
              if ((ssb_start_symbol/14) == rel_slot){
                const int prb_offset = offset_pointa >> scs;
                schedule_ssb(frameP, slotP, scc, dl_req, i_ssb, ssbSubcarrierOffset, offset_pointa, mib_pdu);
                fill_ssb_vrb_map(cc, prb_offset, ssbSubcarrierOffset, ssb_start_symbol, CC_id);
                if (get_softmodem_params()->sa == 1) {
                  get_type0_PDCCH_CSS_config_parameters(&gNB->type0_PDCCH_CSS_config[i_ssb],
                                                        frameP,
                                                        mib,
                                                        slots_per_frame,
                                                        ssbSubcarrierOffset,
                                                        ssb_start_symbol,
                                                        scs,
                                                        FR1,
                                                        band,
                                                        i_ssb,
                                                        ssb_frame_periodicity,
                                                        prb_offset);
                  gNB->type0_PDCCH_CSS_config[i_ssb].active = true;
                }
              }
            }
          }
          break;
        case 3:
          // long bitmap FR2 max 64 SSBs
          num_ssb = 0;
          for (int i_ssb=0; i_ssb<64; i_ssb++) {
            if ((longBitmap->buf[i_ssb/8]>>(7-(i_ssb%8)))&0x01) {
              ssb_start_symbol = get_ssb_start_symbol(band,scs,i_ssb);
              // if start symbol is in current slot, schedule current SSB, fill VRB map and call get_type0_PDCCH_CSS_config_parameters
              if ((ssb_start_symbol/14) == rel_slot){
                const int prb_offset = offset_pointa >> (scs-2); // reference 60kHz
                schedule_ssb(frameP, slotP, scc, dl_req, i_ssb, ssbSubcarrierOffset, offset_pointa, mib_pdu);
                fill_ssb_vrb_map(cc, prb_offset, ssbSubcarrierOffset >> (scs - 2), ssb_start_symbol, CC_id);
                const NR_TDD_UL_DL_Pattern_t *tdd = &scc->tdd_UL_DL_ConfigurationCommon->pattern1;
                const int n_slots_frame = nr_slots_per_frame[*scc->ssbSubcarrierSpacing];
                // FR2 is only TDD, to be fixed for flexible TDD
                const int nr_slots_period = tdd ? n_slots_frame/get_nb_periods_per_frame(scc->tdd_UL_DL_ConfigurationCommon->pattern1.dl_UL_TransmissionPeriodicity) : n_slots_frame;
                num_tdd_period = rel_slot/nr_slots_period;
                gNB->tdd_beam_association[num_tdd_period]=i_ssb;
                num_ssb++;
                AssertFatal(num_ssb<2,"beamforming currently not supported for more than one SSB per slot\n");
                if (get_softmodem_params()->sa == 1) {
                  get_type0_PDCCH_CSS_config_parameters(&gNB->type0_PDCCH_CSS_config[i_ssb],
                                                        frameP,
                                                        mib,
                                                        slots_per_frame,
                                                        ssbSubcarrierOffset,
                                                        ssb_start_symbol,
                                                        scs,
                                                        FR2,
                                                        band,
                                                        i_ssb,
                                                        ssb_frame_periodicity,
                                                        prb_offset);
                  gNB->type0_PDCCH_CSS_config[i_ssb].active = true;
                }
              }
            }
          }
          break;
        default:
          AssertFatal(0,"SSB bitmap size value %d undefined (allowed values 1,2,3)\n",
                      scc->ssb_PositionsInBurst->present);
      }
    }
  }
}

static uint32_t schedule_control_sib1(module_id_t module_id,
                                      int CC_id,
                                      NR_Type0_PDCCH_CSS_config_t *type0_PDCCH_CSS_config,
                                      int time_domain_allocation,
                                      NR_pdsch_dmrs_t *dmrs_parms,
                                      NR_tda_info_t *tda_info,
                                      uint8_t candidate_idx,
                                      uint16_t num_total_bytes)
{
  gNB_MAC_INST *gNB_mac = RC.nrmac[module_id];
  NR_COMMON_channels_t *cc = &gNB_mac->common_channels[CC_id];
  NR_ServingCellConfigCommon_t *scc = cc->ServingCellConfigCommon;
  uint16_t *vrb_map = cc->vrb_map;

  if (gNB_mac->sched_ctrlCommon == NULL){
    LOG_D(NR_MAC,"schedule_control_common: Filling nr_mac->sched_ctrlCommon\n");
    gNB_mac->sched_ctrlCommon = calloc(1,sizeof(*gNB_mac->sched_ctrlCommon));
    gNB_mac->sched_ctrlCommon->search_space = calloc(1,sizeof(*gNB_mac->sched_ctrlCommon->search_space));
    gNB_mac->sched_ctrlCommon->coreset = calloc(1,sizeof(*gNB_mac->sched_ctrlCommon->coreset));
    fill_searchSpaceZero(gNB_mac->sched_ctrlCommon->search_space,
                         nr_slots_per_frame[*scc->ssbSubcarrierSpacing],
                         type0_PDCCH_CSS_config);
    fill_coresetZero(gNB_mac->sched_ctrlCommon->coreset, type0_PDCCH_CSS_config);
    gNB_mac->cset0_bwp_start = type0_PDCCH_CSS_config->cset_start_rb;
    gNB_mac->cset0_bwp_size = type0_PDCCH_CSS_config->num_rbs;
    gNB_mac->sched_ctrlCommon->sched_pdcch = set_pdcch_structure(NULL,
                                                                 gNB_mac->sched_ctrlCommon->search_space,
                                                                 gNB_mac->sched_ctrlCommon->coreset,
                                                                 scc,
                                                                 NULL,
                                                                 type0_PDCCH_CSS_config);
  }

  NR_sched_pdsch_t *pdsch = &gNB_mac->sched_ctrlCommon->sched_pdsch;
  pdsch->time_domain_allocation = time_domain_allocation;
  pdsch->dmrs_parms = *dmrs_parms;
  pdsch->tda_info = *tda_info;
  pdsch->mcs = 0; // starting from mcs 0
  gNB_mac->sched_ctrlCommon->num_total_bytes = num_total_bytes;

  uint8_t nr_of_candidates;

  for (int i=0; i<3; i++) {
    find_aggregation_candidates(&gNB_mac->sched_ctrlCommon->aggregation_level, &nr_of_candidates, gNB_mac->sched_ctrlCommon->search_space,4<<i);
    if (nr_of_candidates>0) break; // choosing the lower value of aggregation level available
  }
  AssertFatal(nr_of_candidates>0,"nr_of_candidates is 0\n");
  gNB_mac->sched_ctrlCommon->cce_index = find_pdcch_candidate(gNB_mac,
                                                              CC_id,
                                                              gNB_mac->sched_ctrlCommon->aggregation_level,
                                                              nr_of_candidates,
                                                              &gNB_mac->sched_ctrlCommon->sched_pdcch,
                                                              gNB_mac->sched_ctrlCommon->coreset,
                                                              0);

  AssertFatal(gNB_mac->sched_ctrlCommon->cce_index >= 0, "Could not find CCE for coreset0\n");

  const uint16_t bwpSize = type0_PDCCH_CSS_config->num_rbs;
  int rbStart = type0_PDCCH_CSS_config->cset_start_rb;

  // Calculate number of PRB_DMRS
  uint8_t N_PRB_DMRS = pdsch->dmrs_parms.N_PRB_DMRS;
  uint16_t dmrs_length = pdsch->dmrs_parms.N_DMRS_SLOT;
  LOG_D(MAC,"dlDmrsSymbPos %x\n",pdsch->dmrs_parms.dl_dmrs_symb_pos);
  int mcsTableIdx = 0;
  int rbSize = 0;
  uint32_t TBS = 0;
  do {
    if(rbSize < bwpSize && !(vrb_map[rbStart + rbSize]&SL_to_bitmap(tda_info->startSymbolIndex, tda_info->nrOfSymbols)))
      rbSize++;
    else{
      if (pdsch->mcs<10)
        pdsch->mcs++;
      else
        break;
    }
    TBS = nr_compute_tbs(nr_get_Qm_dl(pdsch->mcs, mcsTableIdx),
                         nr_get_code_rate_dl(pdsch->mcs, mcsTableIdx),
                         rbSize, tda_info->nrOfSymbols, N_PRB_DMRS * dmrs_length,0, 0,1) >> 3;
  } while (TBS < gNB_mac->sched_ctrlCommon->num_total_bytes);

  if (TBS < gNB_mac->sched_ctrlCommon->num_total_bytes) {
    for (int rb = 0; rb < bwpSize; rb++)
      LOG_I(NR_MAC, "vrb_map[%d] %x\n", rbStart + rb, vrb_map[rbStart + rb]);
  }
  AssertFatal(
      TBS >= gNB_mac->sched_ctrlCommon->num_total_bytes,
      "Couldn't allocate enough resources for %d bytes in SIB1 PDSCH (rbStart %d, rbSize %d, bwpSize %d SLmask %x - [%d,%d])\n",
      gNB_mac->sched_ctrlCommon->num_total_bytes,
      rbStart,
      rbSize,
      bwpSize,
      SL_to_bitmap(tda_info->startSymbolIndex, tda_info->nrOfSymbols),
      tda_info->startSymbolIndex,
      tda_info->nrOfSymbols);

  pdsch->rbSize = rbSize;
  pdsch->rbStart = 0;

  LOG_D(NR_MAC,"mcs = %i\n", pdsch->mcs);
  LOG_D(NR_MAC,"startSymbolIndex = %i\n", tda_info->startSymbolIndex);
  LOG_D(NR_MAC,"nrOfSymbols = %i\n", tda_info->nrOfSymbols);
  LOG_D(NR_MAC, "rbSize = %i\n", pdsch->rbSize);
  LOG_D(NR_MAC,"TBS = %i\n", TBS);
  LOG_D(NR_MAC,"dmrs_length %d\n",dmrs_length);
  LOG_D(NR_MAC,"N_PRB_DMRS = %d\n",N_PRB_DMRS);
  LOG_D(NR_MAC,"mappingtype = %d\n", tda_info->mapping_type);
  // Mark the corresponding RBs as used
  fill_pdcch_vrb_map(gNB_mac,
                     CC_id,
                     &gNB_mac->sched_ctrlCommon->sched_pdcch,
                     gNB_mac->sched_ctrlCommon->cce_index,
                     gNB_mac->sched_ctrlCommon->aggregation_level);
  for (int rb = 0; rb < pdsch->rbSize; rb++) {
    vrb_map[rb + rbStart] |= SL_to_bitmap(tda_info->startSymbolIndex, tda_info->nrOfSymbols);
  }
  return TBS;
}

static void nr_fill_nfapi_dl_sib1_pdu(int Mod_idP,
                                      nfapi_nr_dl_tti_request_body_t *dl_req,
                                      int pdu_index,
                                      NR_Type0_PDCCH_CSS_config_t *type0_PDCCH_CSS_config,
                                      uint32_t TBS,
                                      int StartSymbolIndex,
                                      int NrOfSymbols)
{
  gNB_MAC_INST *gNB_mac = RC.nrmac[Mod_idP];
  NR_COMMON_channels_t *cc = gNB_mac->common_channels;
  NR_ServingCellConfigCommon_t *scc = cc->ServingCellConfigCommon;
  int mcsTableIdx = 0;
  NR_sched_pdsch_t *pdsch = &gNB_mac->sched_ctrlCommon->sched_pdsch;
  nfapi_nr_dl_tti_request_pdu_t *dl_tti_pdcch_pdu = &dl_req->dl_tti_pdu_list[dl_req->nPDUs];
  memset((void*)dl_tti_pdcch_pdu,0,sizeof(nfapi_nr_dl_tti_request_pdu_t));
  dl_tti_pdcch_pdu->PDUType = NFAPI_NR_DL_TTI_PDCCH_PDU_TYPE;
  dl_tti_pdcch_pdu->PDUSize = (uint16_t)(4+sizeof(nfapi_nr_dl_tti_pdcch_pdu));
  dl_req->nPDUs += 1;
  nfapi_nr_dl_tti_pdcch_pdu_rel15_t *pdcch_pdu_rel15 = &dl_tti_pdcch_pdu->pdcch_pdu.pdcch_pdu_rel15;
  nr_configure_pdcch(pdcch_pdu_rel15,
                     gNB_mac->sched_ctrlCommon->coreset,
                     &gNB_mac->sched_ctrlCommon->sched_pdcch);

  nfapi_nr_dl_tti_request_pdu_t *dl_tti_pdsch_pdu = &dl_req->dl_tti_pdu_list[dl_req->nPDUs];
  memset((void*)dl_tti_pdsch_pdu,0,sizeof(nfapi_nr_dl_tti_request_pdu_t));
  dl_tti_pdsch_pdu->PDUType = NFAPI_NR_DL_TTI_PDSCH_PDU_TYPE;
  dl_tti_pdsch_pdu->PDUSize = (uint16_t)(4+sizeof(nfapi_nr_dl_tti_pdsch_pdu));
  dl_req->nPDUs += 1;
  nfapi_nr_dl_tti_pdsch_pdu_rel15_t *pdsch_pdu_rel15 = &dl_tti_pdsch_pdu->pdsch_pdu.pdsch_pdu_rel15;

  pdsch_pdu_rel15->precodingAndBeamforming.num_prgs=0;
  pdsch_pdu_rel15->precodingAndBeamforming.prg_size=0;
  pdsch_pdu_rel15->precodingAndBeamforming.dig_bf_interfaces=0;
  pdsch_pdu_rel15->precodingAndBeamforming.prgs_list[0].pm_idx = 0;
  pdsch_pdu_rel15->precodingAndBeamforming.prgs_list[0].dig_bf_interface_list[0].beam_idx = 0;

  pdcch_pdu_rel15->CoreSetType = NFAPI_NR_CSET_CONFIG_MIB_SIB1;

  pdsch_pdu_rel15->pduBitmap = 0;
  pdsch_pdu_rel15->rnti = SI_RNTI;
  pdsch_pdu_rel15->pduIndex = pdu_index;

  pdsch_pdu_rel15->BWPSize  = type0_PDCCH_CSS_config->num_rbs;
  pdsch_pdu_rel15->BWPStart = type0_PDCCH_CSS_config->cset_start_rb;

  pdsch_pdu_rel15->SubcarrierSpacing = type0_PDCCH_CSS_config->scs_pdcch;
  pdsch_pdu_rel15->CyclicPrefix = 0;

  pdsch_pdu_rel15->NrOfCodewords = 1;
  pdsch_pdu_rel15->targetCodeRate[0] = nr_get_code_rate_dl(pdsch->mcs, mcsTableIdx);
  pdsch_pdu_rel15->qamModOrder[0] = nr_get_Qm_dl(pdsch->mcs, mcsTableIdx);
  pdsch_pdu_rel15->mcsIndex[0] = pdsch->mcs;
  pdsch_pdu_rel15->mcsTable[0] = mcsTableIdx;
  pdsch_pdu_rel15->rvIndex[0] = nr_rv_round_map[0];
  pdsch_pdu_rel15->dataScramblingId = *scc->physCellId;
  pdsch_pdu_rel15->nrOfLayers = 1;
  pdsch_pdu_rel15->transmissionScheme = 0;
  pdsch_pdu_rel15->refPoint = 1;
  pdsch_pdu_rel15->dmrsConfigType = 0;
  pdsch_pdu_rel15->dlDmrsScramblingId = *scc->physCellId;
  pdsch_pdu_rel15->SCID = 0;
  pdsch_pdu_rel15->numDmrsCdmGrpsNoData = pdsch->dmrs_parms.numDmrsCdmGrpsNoData;
  pdsch_pdu_rel15->dmrsPorts = 1;
  pdsch_pdu_rel15->resourceAlloc = 1;
  pdsch_pdu_rel15->rbStart = pdsch->rbStart;
  pdsch_pdu_rel15->rbSize = pdsch->rbSize;
  pdsch_pdu_rel15->VRBtoPRBMapping = 0;
  pdsch_pdu_rel15->TBSize[0] = TBS;
  pdsch_pdu_rel15->StartSymbolIndex = StartSymbolIndex;
  pdsch_pdu_rel15->NrOfSymbols = NrOfSymbols;
  pdsch_pdu_rel15->dlDmrsSymbPos = pdsch->dmrs_parms.dl_dmrs_symb_pos;
  LOG_D(NR_MAC,"sib1:bwpStart %d, bwpSize %d\n",pdsch_pdu_rel15->BWPStart,pdsch_pdu_rel15->BWPSize);
  LOG_D(NR_MAC,"sib1:rbStart %d, rbSize %d\n",pdsch_pdu_rel15->rbStart,pdsch_pdu_rel15->rbSize);
  LOG_D(NR_MAC,"sib1:dlDmrsSymbPos = 0x%x\n", pdsch_pdu_rel15->dlDmrsSymbPos);

  pdsch_pdu_rel15->maintenance_parms_v3.tbSizeLbrmBytes = nr_compute_tbslbrm(0,
                                                                             pdsch_pdu_rel15->BWPSize,
                                                                             1);
  pdsch_pdu_rel15->maintenance_parms_v3.ldpcBaseGraph = get_BG(TBS<<3,pdsch_pdu_rel15->targetCodeRate[0]);

  /* Fill PDCCH DL DCI PDU */
  nfapi_nr_dl_dci_pdu_t *dci_pdu = &pdcch_pdu_rel15->dci_pdu[pdcch_pdu_rel15->numDlDci];
  pdcch_pdu_rel15->numDlDci++;
  dci_pdu->RNTI = SI_RNTI;
  dci_pdu->ScramblingId = *scc->physCellId;
  dci_pdu->ScramblingRNTI = 0;
  dci_pdu->AggregationLevel = gNB_mac->sched_ctrlCommon->aggregation_level;
  dci_pdu->CceIndex = gNB_mac->sched_ctrlCommon->cce_index;
  dci_pdu->beta_PDCCH_1_0 = 0;
  dci_pdu->powerControlOffsetSS = 1;

  /* DCI payload */
  dci_pdu_rel15_t dci_payload;
  memset(&dci_payload, 0, sizeof(dci_pdu_rel15_t));

  dci_payload.bwp_indicator.val = 0;

  // frequency domain assignment
  dci_payload.frequency_domain_assignment.val = PRBalloc_to_locationandbandwidth0(
      pdsch_pdu_rel15->rbSize, pdsch_pdu_rel15->rbStart, type0_PDCCH_CSS_config->num_rbs);

  dci_payload.time_domain_assignment.val = gNB_mac->sched_ctrlCommon->sched_pdsch.time_domain_allocation;
  dci_payload.mcs = pdsch->mcs;
  dci_payload.rv = pdsch_pdu_rel15->rvIndex[0];
  dci_payload.harq_pid = 0;
  dci_payload.ndi = 0;
  dci_payload.dai[0].val = 0;
  dci_payload.tpc = 0; // table 7.2.1-1 in 38.213
  dci_payload.pucch_resource_indicator = 0;
  dci_payload.pdsch_to_harq_feedback_timing_indicator.val = 0;
  dci_payload.antenna_ports.val = 0;
  dci_payload.dmrs_sequence_initialization.val = pdsch_pdu_rel15->SCID;

  int dci_format = NR_DL_DCI_FORMAT_1_0;
  int rnti_type = TYPE_SI_RNTI_;

  fill_dci_pdu_rel15(NULL,
                     NULL,
                     NULL,
                     &pdcch_pdu_rel15->dci_pdu[pdcch_pdu_rel15->numDlDci - 1],
                     &dci_payload,
                     dci_format,
                     rnti_type,
                     0,
                     gNB_mac->sched_ctrlCommon->search_space,
                     gNB_mac->sched_ctrlCommon->coreset,
                     0, // parameter not needed for DCI 1_0
                     gNB_mac->cset0_bwp_size);

  LOG_D(MAC,"BWPSize: %i\n", pdcch_pdu_rel15->BWPSize);
  LOG_D(MAC,"BWPStart: %i\n", pdcch_pdu_rel15->BWPStart);
  LOG_D(MAC,"SubcarrierSpacing: %i\n", pdcch_pdu_rel15->SubcarrierSpacing);
  LOG_D(MAC,"CyclicPrefix: %i\n", pdcch_pdu_rel15->CyclicPrefix);
  LOG_D(MAC,"StartSymbolIndex: %i\n", pdcch_pdu_rel15->StartSymbolIndex);
  LOG_D(MAC,"DurationSymbols: %i\n", pdcch_pdu_rel15->DurationSymbols);
  for(int n=0;n<6;n++) LOG_D(MAC,"FreqDomainResource[%i]: %x\n",n, pdcch_pdu_rel15->FreqDomainResource[n]);
  LOG_D(MAC,"CceRegMappingType: %i\n", pdcch_pdu_rel15->CceRegMappingType);
  LOG_D(MAC,"RegBundleSize: %i\n", pdcch_pdu_rel15->RegBundleSize);
  LOG_D(MAC,"InterleaverSize: %i\n", pdcch_pdu_rel15->InterleaverSize);
  LOG_D(MAC,"CoreSetType: %i\n", pdcch_pdu_rel15->CoreSetType);
  LOG_D(MAC,"ShiftIndex: %i\n", pdcch_pdu_rel15->ShiftIndex);
  LOG_D(MAC,"precoderGranularity: %i\n", pdcch_pdu_rel15->precoderGranularity);
  LOG_D(MAC,"numDlDci: %i\n", pdcch_pdu_rel15->numDlDci);
}

void schedule_nr_sib1(module_id_t module_idP,
                      frame_t frameP,
                      sub_frame_t slotP,
                      nfapi_nr_dl_tti_request_t *DL_req,
                      nfapi_nr_tx_data_request_t *TX_req)
{
  /* already mutex protected: held in gNB_dlsch_ulsch_scheduler() */
  // TODO: Get these values from RRC
  const int CC_id = 0;
  uint8_t candidate_idx = 0;

  gNB_MAC_INST *gNB_mac = RC.nrmac[module_idP];
  NR_ServingCellConfigCommon_t *scc = gNB_mac->common_channels[CC_id].ServingCellConfigCommon;

  int time_domain_allocation = gNB_mac->radio_config.sib1_tda;

  int L_max;
  switch (scc->ssb_PositionsInBurst->present) {
    case 1:
      L_max = 4;
      break;
    case 2:
      L_max = 8;
      break;
    case 3:
      L_max = 64;
      break;
    default:
      AssertFatal(0,"SSB bitmap size value %d undefined (allowed values 1,2,3)\n",
                  scc->ssb_PositionsInBurst->present);
  }

  for (int i=0; i<L_max; i++) {

    NR_Type0_PDCCH_CSS_config_t *type0_PDCCH_CSS_config = &gNB_mac->type0_PDCCH_CSS_config[i];

    if((frameP%2 == type0_PDCCH_CSS_config->sfn_c) &&
       (slotP == type0_PDCCH_CSS_config->n_0) &&
       (type0_PDCCH_CSS_config->num_rbs > 0) &&
       (type0_PDCCH_CSS_config->active == true)) {

      LOG_D(NR_MAC,"(%d.%d) SIB1 transmission: ssb_index %d\n", frameP, slotP, type0_PDCCH_CSS_config->ssb_index);

      default_table_type_t table_type = get_default_table_type(type0_PDCCH_CSS_config->type0_pdcch_ss_mux_pattern);
      // assuming normal CP
      NR_tda_info_t tda_info = get_info_from_tda_tables(table_type, time_domain_allocation, gNB_mac->common_channels->ServingCellConfigCommon->dmrs_TypeA_Position, true);

      AssertFatal((tda_info.startSymbolIndex + tda_info.nrOfSymbols) < 14, "SIB1 TDA %d would cause overlap with CSI-RS. Please select a different SIB1 TDA.\n", time_domain_allocation);

      NR_pdsch_dmrs_t dmrs_parms = get_dl_dmrs_params(scc,
                                                      NULL,
                                                      &tda_info,
                                                      1);


      NR_COMMON_channels_t *cc = &gNB_mac->common_channels[0];
      // Configure sched_ctrlCommon for SIB1
      uint32_t TBS = schedule_control_sib1(module_idP, CC_id,
                                           type0_PDCCH_CSS_config,
                                           time_domain_allocation,
                                           &dmrs_parms,
                                           &tda_info,
                                           candidate_idx,
                                           cc->sib1_bcch_length);

      nfapi_nr_dl_tti_request_body_t *dl_req = &DL_req->dl_tti_request_body;
      int pdu_index = gNB_mac->pdu_index[0]++;
      nr_fill_nfapi_dl_sib1_pdu(module_idP, dl_req, pdu_index, type0_PDCCH_CSS_config, TBS, tda_info.startSymbolIndex, tda_info.nrOfSymbols);

      const int ntx_req = TX_req->Number_of_PDUs;
      nfapi_nr_pdu_t *tx_req = &TX_req->pdu_list[ntx_req];

      // Data to be transmitted
      memcpy(tx_req->TLVs[0].value.direct, cc->sib1_bcch_pdu, TBS);

      tx_req->PDU_index  = pdu_index;
      tx_req->num_TLV = 1;
      tx_req->TLVs[0].length = TBS;
      tx_req->PDU_length = compute_PDU_length(tx_req->num_TLV, tx_req->TLVs[0].length);
      TX_req->Number_of_PDUs++;
      TX_req->SFN = frameP;
      TX_req->Slot = slotP;

      type0_PDCCH_CSS_config->active = false;

      T(T_GNB_MAC_DL_PDU_WITH_DATA,
        T_INT(module_idP),
        T_INT(CC_id),
        T_INT(0xffff),
        T_INT(frameP),
        T_INT(slotP),
        T_INT(0 /* harq_pid */),
        T_BUFFER(cc->sib1_bcch_pdu, cc->sib1_bcch_length));
    }
  }
}
