/*
 * 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 "phy_init.h"
#include "common/utils/LOG/log.h"
#include "LAYER2/NR_MAC_gNB/mac_proto.h"

/// Subcarrier spacings in Hz indexed by numerology index
uint32_t nr_subcarrier_spacing[MAX_NUM_SUBCARRIER_SPACING] = {15e3, 30e3, 60e3, 120e3, 240e3};
uint16_t nr_slots_per_subframe[MAX_NUM_SUBCARRIER_SPACING] = {1, 2, 4, 8, 16};



int nr_get_ssb_start_symbol(NR_DL_FRAME_PARMS *fp)
{

  int mu = fp->numerology_index;
  uint8_t half_frame_index = fp->half_frame_bit;
  uint8_t i_ssb = fp->ssb_index;
  int symbol = 0;
  uint8_t n, n_temp;
  nr_ssb_type_e type = fp->ssb_type;
  int case_AC[2] = {2,8};
  int case_BD[4] = {4,8,16,20};
  int case_E[8] = {8, 12, 16, 20, 32, 36, 40, 44};

  switch(mu) {

	case NR_MU_0: // case A
	    n = i_ssb >> 1;
	    symbol = case_AC[i_ssb % 2] + 14*n;
	break;

	case NR_MU_1: 
	    if (type == 1){ // case B
		n = i_ssb >> 2;
	    	symbol = case_BD[i_ssb % 4] + 28*n;
	    }
	    if (type == 2){ // case C
		n = i_ssb >> 1;
		symbol = case_AC[i_ssb % 2] + 14*n;
	    }
	 break;

	 case NR_MU_3: // case D
	    n_temp = i_ssb >> 2; 
	    n = n_temp + (n_temp >> 2);
	    symbol = case_BD[i_ssb % 4] + 28*n;
	 break;

	 case NR_MU_4:  // case E
	    n_temp = i_ssb >> 3; 
	    n = n_temp + (n_temp >> 2);
	    symbol = case_E[i_ssb % 8] + 56*n;
	 break;


	 default:
	      AssertFatal(0==1, "Invalid numerology index %d for the synchronization block\n", mu);
  }

  if (half_frame_index)
    symbol += (5 * fp->symbols_per_slot * fp->slots_per_subframe);

  return symbol;
}

void set_scs_parameters (NR_DL_FRAME_PARMS *fp, int mu, uint16_t bw)
{
  switch(mu) {

    case NR_MU_0: //15kHz scs
      fp->subcarrier_spacing = nr_subcarrier_spacing[NR_MU_0];
      fp->slots_per_subframe = nr_slots_per_subframe[NR_MU_0];
      fp->ssb_type = nr_ssb_type_A;
      break;

    case NR_MU_1: //30kHz scs
      fp->subcarrier_spacing = nr_subcarrier_spacing[NR_MU_1];
      fp->slots_per_subframe = nr_slots_per_subframe[NR_MU_1];

      // selection of SS block pattern according to TS 38101-1 Table 5.4.3.3-1 for SCS 30kHz
      if (fp->nr_band == 5 || fp->nr_band == 66) 
        fp->ssb_type = nr_ssb_type_B;
      else{  
      	if (fp->nr_band == 41 || ( fp->nr_band > 76 && fp->nr_band < 80) )
	  fp->ssb_type = nr_ssb_type_C;
	else
	  AssertFatal(1==0,"NR Operating Band n%d not available for SS block SCS with mu=%d\n", fp->nr_band, mu);
      }

      switch(bw){
        case 5:
        case 15:
        case 20:
        case 25:
        case 30:
        case 40: //40 MHz
          if (fp->threequarter_fs) {
            fp->ofdm_symbol_size = 1536;
            fp->first_carrier_offset = 900; //1536 - ( (106*12) / 2 )
            fp->nb_prefix_samples0 = 132;
            fp->nb_prefix_samples = 108;
          }
          else {
            fp->ofdm_symbol_size = 2048;
            fp->first_carrier_offset = 1412; //2048 - ( (106*12) / 2 )
            fp->nb_prefix_samples0 = 176;
            fp->nb_prefix_samples = 144;
          }
          break;

        case 50:
        case 60:
        case 70:

        case 80: //80 MHz
          if (fp->threequarter_fs) {
            fp->ofdm_symbol_size = 3072;
            fp->first_carrier_offset = 1770; //3072 - ( (217*12) / 2 )
            fp->nb_prefix_samples0 = 264;
            fp->nb_prefix_samples = 216;
          }
	  else {
	    fp->ofdm_symbol_size = 4096;
	    fp->first_carrier_offset = 2794; //4096 - ( (217*12) / 2 )
	    fp->nb_prefix_samples0 = 352;
	    fp->nb_prefix_samples = 288;
	  }
          break;

        case 90:
	  AssertFatal(fp->threequarter_fs==0,"3/4 sampling impossible for %d MHz band and MU %d\n",bw,mu); 
	  fp->ofdm_symbol_size = 4096;
	  fp->first_carrier_offset = 2626; //4096 - ( (245*12) / 2 )
	  fp->nb_prefix_samples0 = 352;
	  fp->nb_prefix_samples = 288;
	  break;
        case 100:
	  AssertFatal(fp->threequarter_fs==0,"3/4 sampling impossible for %d MHz band and MU %d\n",bw,mu); 
	  fp->ofdm_symbol_size = 4096;
	  fp->first_carrier_offset = 2458; //4096 - ( (273*12) / 2 )
	  fp->nb_prefix_samples0 = 352;
	  fp->nb_prefix_samples = 288;
	  break;
      default:
        AssertFatal(1==0,"%d MHz band undefined for mu %d, frame parms = %p\n", bw, mu, fp);
      }
      break;

    case NR_MU_2: //60kHz scs
      fp->subcarrier_spacing = nr_subcarrier_spacing[NR_MU_2];
      fp->slots_per_subframe = nr_slots_per_subframe[NR_MU_2];

      switch(bw){ //FR1 bands only
        case 10:
        case 15:
        case 20:
        case 25:
        case 30:
        case 40:
        case 50:
        case 60:
        case 70:
        case 80:
        case 90:
        case 100:
      default:
        AssertFatal(1==0,"%d MHz band undefined for mu %d, frame parms = %p\n", bw, mu, fp);
      }
      break;

    case NR_MU_3:
      fp->subcarrier_spacing = nr_subcarrier_spacing[NR_MU_3];
      fp->slots_per_subframe = nr_slots_per_subframe[NR_MU_3];
      fp->ssb_type = nr_ssb_type_D;
      switch(bw){
        case 100:
          fp->ofdm_symbol_size = 1024;
          fp->first_carrier_offset = 628; //1024 - ( (66*12) / 2 )
          fp->nb_prefix_samples0 = 136;
          fp->nb_prefix_samples = 72;
          break;
        case 50:
          fp->ofdm_symbol_size = 512;
          fp->first_carrier_offset = 320; //1024 - ( (66*12) / 2 )
          fp->nb_prefix_samples0 = 68;
          fp->nb_prefix_samples = 36;
          break;
      default:
        AssertFatal(1==0,"%d MHz band undefined for mu %d, frame parms = %p\n", bw, mu, fp);
      }
      break;

    case NR_MU_4:
      fp->subcarrier_spacing = nr_subcarrier_spacing[NR_MU_4];
      fp->slots_per_subframe = nr_slots_per_subframe[NR_MU_4];
      fp->ssb_type = nr_ssb_type_E;
      break;

  default:
    AssertFatal(1==0,"Invalid numerology index %d", mu);
  }
}

uint32_t get_samples_per_slot(int slot, NR_DL_FRAME_PARMS* fp)
{
  uint32_t samp_count;

  if(fp->numerology_index == 0)
    samp_count = fp->samples_per_subframe;
  else
    samp_count = (slot%(fp->slots_per_subframe/2)) ? fp->samples_per_slotN0 : fp->samples_per_slot0;

  return samp_count;
}

uint32_t get_samples_slot_timestamp(int slot, NR_DL_FRAME_PARMS* fp, uint8_t sl_ahead)
{
  uint32_t samp_count = 0;

  if(!sl_ahead) {
    for(uint8_t idx_slot = 0; idx_slot < slot; idx_slot++)
      samp_count += fp->get_samples_per_slot(idx_slot, fp);
  } else {
    for(uint8_t idx_slot = slot; idx_slot < slot+sl_ahead; idx_slot++)
      samp_count += fp->get_samples_per_slot(idx_slot, fp);
  }
  return samp_count;
}

int nr_init_frame_parms(nfapi_nr_config_request_scf_t* cfg,
                        NR_DL_FRAME_PARMS *fp)
{

  fp->frame_type = cfg->cell_config.frame_duplex_type.value;
  fp->L_ssb = (((uint64_t) cfg->ssb_table.ssb_mask_list[0].ssb_mask.value)<<32) | cfg->ssb_table.ssb_mask_list[1].ssb_mask.value ;
  fp->N_RB_DL = cfg->carrier_config.dl_grid_size[cfg->ssb_config.scs_common.value].value;
  fp->N_RB_UL = cfg->carrier_config.ul_grid_size[cfg->ssb_config.scs_common.value].value;

  int Ncp = NFAPI_CP_NORMAL;
  int mu = cfg!= NULL ?  cfg->ssb_config.scs_common.value : 0;

#if DISABLE_LOG_X
  printf("Initializing frame parms for mu %d, N_RB %d, Ncp %d\n",mu, fp->N_RB_DL, Ncp);
#else
  LOG_I(PHY,"Initializing frame parms for mu %d, N_RB %d, Ncp %d\n",mu, fp->N_RB_DL, Ncp);
#endif

  if (Ncp == NFAPI_CP_EXTENDED)
    AssertFatal(mu == NR_MU_2,"Invalid cyclic prefix %d for numerology index %d\n", Ncp, mu);

  fp->half_frame_bit = 0;  // half frame bit initialized to 0 here
  fp->numerology_index = mu;

  set_scs_parameters(fp, mu, cfg->carrier_config.dl_bandwidth.value);

  fp->slots_per_frame = 10* fp->slots_per_subframe;

  fp->nb_antenna_ports_gNB = 1; // default value until overwritten by RRCConnectionReconfiguration
  fp->nb_antennas_rx = 1; // default value until overwritten by RRCConnectionReconfiguration
  fp->nb_antennas_tx = 1; // default value until overwritten by RRCConnectionReconfiguration

  fp->symbols_per_slot = ((Ncp == NORMAL)? 14 : 12); // to redefine for different slot formats
  fp->samples_per_subframe_wCP = fp->ofdm_symbol_size * fp->symbols_per_slot * fp->slots_per_subframe;
  fp->samples_per_frame_wCP = 10 * fp->samples_per_subframe_wCP;
  fp->samples_per_slot_wCP = fp->symbols_per_slot*fp->ofdm_symbol_size; 
  fp->samples_per_slotN0 = (fp->nb_prefix_samples + fp->ofdm_symbol_size) * fp->symbols_per_slot;
  fp->samples_per_slot0 = fp->nb_prefix_samples0 + ((fp->symbols_per_slot-1)*fp->nb_prefix_samples) + (fp->symbols_per_slot*fp->ofdm_symbol_size); 
  fp->samples_per_subframe = (fp->nb_prefix_samples0 + fp->ofdm_symbol_size) * 2 + 
                             (fp->nb_prefix_samples + fp->ofdm_symbol_size) * (fp->symbols_per_slot * fp->slots_per_subframe - 2); 
  fp->get_samples_per_slot = &get_samples_per_slot;
  fp->get_samples_slot_timestamp = &get_samples_slot_timestamp;
  fp->samples_per_frame = 10 * fp->samples_per_subframe;
  fp->freq_range = (fp->dl_CarrierFreq < 6e9)? nr_FR1 : nr_FR2;

  fp->Ncp = Ncp;

  // definition of Lmax according to ts 38.213 section 4.1
  if (fp->dl_CarrierFreq < 6e9) {
    if(fp->frame_type && (fp->ssb_type==2))
      fp->Lmax = (fp->dl_CarrierFreq < 2.4e9)? 4 : 8;
    else
      fp->Lmax = (fp->dl_CarrierFreq < 3e9)? 4 : 8;
  } else {
    fp->Lmax = 64;
  }

  fp->N_ssb = 0;
  int num_tx_ant = (cfg == NULL) ? fp->Lmax : cfg->carrier_config.num_tx_ant.value;

  for (int p=0; p<num_tx_ant; p++)
    fp->N_ssb += ((fp->L_ssb >> (63-p)) & 0x01);

  return 0;

}

int nr_init_frame_parms_ue(NR_DL_FRAME_PARMS *fp,
			   fapi_nr_config_request_t* config, 
			   int Ncp) 
{

  uint64_t dl_bw_khz = (12*config->carrier_config.dl_grid_size[config->ssb_config.scs_common])*(15<<config->ssb_config.scs_common);
  fp->dl_CarrierFreq = ((dl_bw_khz>>1) + config->carrier_config.dl_frequency)*1000 ;

  uint64_t ul_bw_khz = (12*config->carrier_config.ul_grid_size[config->ssb_config.scs_common])*(15<<config->ssb_config.scs_common);
  fp->ul_CarrierFreq = ((ul_bw_khz>>1) + config->carrier_config.uplink_frequency)*1000 ;

  fp->numerology_index = config->ssb_config.scs_common;
  fp->N_RB_UL = config->carrier_config.ul_grid_size[fp->numerology_index];
  fp->N_RB_DL = config->carrier_config.dl_grid_size[fp->numerology_index];

  int32_t uplink_frequency_offset = 0;

  get_band(fp->dl_CarrierFreq, &fp->nr_band, &uplink_frequency_offset, &fp->frame_type);

  AssertFatal(fp->frame_type==config->cell_config.frame_duplex_type, "Invalid duplex type in config request file for band %d\n", fp->nr_band);
  AssertFatal(fp->ul_CarrierFreq==(fp->dl_CarrierFreq+uplink_frequency_offset), "Disagreement in uplink frequency for band %d\n", fp->nr_band);

#if DISABLE_LOG_X
  printf("Initializing UE frame parms for mu %d, N_RB %d, Ncp %d\n",fp->numerology_index, fp->N_RB_DL, Ncp);
#else
  LOG_I(PHY,"Initializing frame parms for mu %d, N_RB %d, Ncp %d\n",fp->numerology_index, fp->N_RB_DL, Ncp);
#endif

  if (Ncp == NFAPI_CP_EXTENDED)
    AssertFatal(fp->numerology_index == NR_MU_2,"Invalid cyclic prefix %d for numerology index %d\n", Ncp, fp->numerology_index);

  fp->Ncp = Ncp;

  set_scs_parameters(fp,fp->numerology_index,config->carrier_config.dl_bandwidth);

  fp->slots_per_frame = 10* fp->slots_per_subframe;

  fp->nb_antenna_ports_gNB = 1; // default value until overwritten by RRCConnectionReconfiguration
  fp->nb_antennas_rx = 1; // default value until overwritten by RRCConnectionReconfiguration
  fp->nb_antennas_tx = 1; // default value until overwritten by RRCConnectionReconfiguration

  fp->symbols_per_slot = ((Ncp == NORMAL)? 14 : 12); // to redefine for different slot formats
  fp->samples_per_subframe_wCP = fp->ofdm_symbol_size * fp->symbols_per_slot * fp->slots_per_subframe;
  fp->samples_per_frame_wCP = 10 * fp->samples_per_subframe_wCP;
  fp->samples_per_slot_wCP = fp->symbols_per_slot*fp->ofdm_symbol_size; 
  fp->samples_per_slotN0 = (fp->nb_prefix_samples + fp->ofdm_symbol_size) * fp->symbols_per_slot;
  fp->samples_per_slot0 = fp->nb_prefix_samples0 + ((fp->symbols_per_slot-1)*fp->nb_prefix_samples) + (fp->symbols_per_slot*fp->ofdm_symbol_size); 
  fp->samples_per_subframe = (fp->nb_prefix_samples0 + fp->ofdm_symbol_size) * 2 + 
                             (fp->nb_prefix_samples + fp->ofdm_symbol_size) * (fp->symbols_per_slot * fp->slots_per_subframe - 2); 
  fp->get_samples_per_slot = &get_samples_per_slot;
  fp->get_samples_slot_timestamp = &get_samples_slot_timestamp;
  fp->samples_per_frame = 10 * fp->samples_per_subframe;
  fp->freq_range = (fp->dl_CarrierFreq < 6e9)? nr_FR1 : nr_FR2;

  uint8_t sco = 0;
  if (((fp->freq_range == nr_FR1) && (config->ssb_table.ssb_subcarrier_offset<24)) ||
      ((fp->freq_range == nr_FR2) && (config->ssb_table.ssb_subcarrier_offset<12)) )
    sco = config->ssb_table.ssb_subcarrier_offset;

  fp->ssb_start_subcarrier = (12 * config->ssb_table.ssb_offset_point_a + sco);

  // definition of Lmax according to ts 38.213 section 4.1
  if (fp->dl_CarrierFreq < 6e9) {
    if(fp->frame_type && (fp->ssb_type==2))
      fp->Lmax = (fp->dl_CarrierFreq < 2.4e9)? 4 : 8;
    else
      fp->Lmax = (fp->dl_CarrierFreq < 3e9)? 4 : 8;
  } else {
    fp->Lmax = 64;
  }

  fp->L_ssb = (((uint64_t) config->ssb_table.ssb_mask_list[0].ssb_mask)<<32) | config->ssb_table.ssb_mask_list[1].ssb_mask;
  
  fp->N_ssb = 0;
  for (int p=0; p<fp->Lmax; p++)
    fp->N_ssb += ((fp->L_ssb >> (63-p)) & 0x01);

  return 0;
}

void nr_dump_frame_parms(NR_DL_FRAME_PARMS *fp)
{
  LOG_I(PHY,"fp->scs=%d\n",fp->subcarrier_spacing);
  LOG_I(PHY,"fp->ofdm_symbol_size=%d\n",fp->ofdm_symbol_size);
  LOG_I(PHY,"fp->nb_prefix_samples0=%d\n",fp->nb_prefix_samples0);
  LOG_I(PHY,"fp->nb_prefix_samples=%d\n",fp->nb_prefix_samples);
  LOG_I(PHY,"fp->slots_per_subframe=%d\n",fp->slots_per_subframe);
  LOG_I(PHY,"fp->samples_per_subframe_wCP=%d\n",fp->samples_per_subframe_wCP);
  LOG_I(PHY,"fp->samples_per_frame_wCP=%d\n",fp->samples_per_frame_wCP);
  LOG_I(PHY,"fp->samples_per_subframe=%d\n",fp->samples_per_subframe);
  LOG_I(PHY,"fp->samples_per_frame=%d\n",fp->samples_per_frame);
  LOG_I(PHY,"fp->dl_CarrierFreq=%lu\n",fp->dl_CarrierFreq);
  LOG_I(PHY,"fp->ul_CarrierFreq=%lu\n",fp->ul_CarrierFreq);
}



