/*
 * 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 openair2/NR_PHY_INTERFACE/NR_IF_Module.c
* \brief data structures for PHY/MAC interface modules
* \author EURECOM/NTUST
* \date 2018
* \version 0.1
* \company Eurecom, NTUST
* \email: raymond.knopp@eurecom.fr, kroempa@gmail.com
* \note
* \warning
*/

#include "openair1/PHY/defs_eNB.h"
#include "openair1/PHY/phy_extern.h"
#include "openair1/SCHED_NR/fapi_nr_l1.h"
#include "openair2/NR_PHY_INTERFACE/NR_IF_Module.h"
#include "LAYER2/NR_MAC_COMMON/nr_mac_extern.h"
#include "LAYER2/MAC/mac_proto.h"
#include "LAYER2/NR_MAC_gNB/mac_proto.h"
#include "common/ran_context.h"
#include "executables/softmodem-common.h"

#define MAX_IF_MODULES 100

NR_IF_Module_t *if_inst[MAX_IF_MODULES];
NR_Sched_Rsp_t Sched_INFO[MAX_IF_MODULES][MAX_NUM_CCs];

extern int oai_nfapi_harq_indication(nfapi_harq_indication_t *harq_ind);
extern int oai_nfapi_crc_indication(nfapi_crc_indication_t *crc_ind);
extern int oai_nfapi_cqi_indication(nfapi_cqi_indication_t *cqi_ind);
extern int oai_nfapi_sr_indication(nfapi_sr_indication_t *ind);
extern int oai_nfapi_rx_ind(nfapi_rx_indication_t *ind);
extern uint8_t nfapi_mode;
extern uint16_t sf_ahead;
extern uint16_t sl_ahead;

void handle_nr_rach(NR_UL_IND_t *UL_info) {
  if (UL_info->rach_ind.number_of_pdus>0) {
    AssertFatal(UL_info->rach_ind.number_of_pdus==1,"More than 1 RACH pdu not supported\n");
    UL_info->rach_ind.number_of_pdus=0;
    LOG_D(MAC,"UL_info[Frame %d, Slot %d] Calling initiate_ra_proc RACH:SFN/SLOT:%d/%d\n",UL_info->frame,UL_info->slot, UL_info->rach_ind.sfn,UL_info->rach_ind.slot);

    if (UL_info->rach_ind.pdu_list[0].num_preamble>0)
    AssertFatal(UL_info->rach_ind.pdu_list[0].num_preamble==1,
		"More than 1 preamble not supported\n");
    
    nr_initiate_ra_proc(UL_info->module_id,
                        UL_info->CC_id,
                        UL_info->rach_ind.sfn,
                        UL_info->rach_ind.slot,
                        UL_info->rach_ind.pdu_list[0].preamble_list[0].preamble_index,
                        UL_info->rach_ind.pdu_list[0].freq_index,
                        UL_info->rach_ind.pdu_list[0].symbol_index,
                        UL_info->rach_ind.pdu_list[0].preamble_list[0].timing_advance);

  }
}


void handle_nr_uci(NR_UL_IND_t *UL_info, NR_UE_sched_ctrl_t *sched_ctrl) {
  // TODO
  int max_harq_rounds = 4; // TODO define macro
  int num_ucis = UL_info->uci_ind.num_ucis;
  nfapi_nr_uci_t *uci_list = UL_info->uci_ind.uci_list;

  for (int i = 0; i < num_ucis; i++) {
    switch (uci_list[i].pdu_type) {
      case NFAPI_NR_UCI_PDCCH_PDU_TYPE: break;

      case NFAPI_NR_UCI_FORMAT_0_1_PDU_TYPE: {
        if (get_softmodem_params()->phy_test == 0) {
          nfapi_nr_uci_pucch_pdu_format_0_1_t *uci_pdu = &uci_list[i].pucch_pdu_format_0_1;
          // handle harq
          int harq_idx_s = 0;
          // iterate over received harq bits
          for (int harq_bit = 0; harq_bit < uci_pdu->harq->num_harq; harq_bit++) {
            // search for the right harq process
            for (int harq_idx = harq_idx_s; harq_idx < NR_MAX_NB_HARQ_PROCESSES-1; harq_idx++) {
              if ((UL_info->slot-1) == sched_ctrl->harq_processes[harq_idx].feedback_slot) {
                if (uci_pdu->harq->harq_list[harq_bit].harq_value == 0)
                  sched_ctrl->harq_processes[harq_idx].round++;
                if ((uci_pdu->harq->harq_list[harq_bit].harq_value == 1) ||
                   (sched_ctrl->harq_processes[harq_idx].round == max_harq_rounds)) {
                  sched_ctrl->harq_processes[harq_idx].ndi ^= 1;
                  sched_ctrl->harq_processes[harq_idx].round = 0;
                }
                sched_ctrl->harq_processes[harq_idx].is_waiting = 0;
                harq_idx_s = harq_idx + 1;
                break;
              }
              // if gNB fails to receive a ACK/NACK
              else if (((UL_info->slot-1) > sched_ctrl->harq_processes[harq_idx].feedback_slot) &&
                      (sched_ctrl->harq_processes[harq_idx].is_waiting)) {
                sched_ctrl->harq_processes[harq_idx].round++;
                if (sched_ctrl->harq_processes[harq_idx].round == max_harq_rounds) {
                  sched_ctrl->harq_processes[harq_idx].ndi ^= 1;
                  sched_ctrl->harq_processes[harq_idx].round = 0;
                }
                sched_ctrl->harq_processes[harq_idx].is_waiting = 0;
              }
            }
          }
        }
        break;
      }

      case NFAPI_NR_UCI_FORMAT_2_3_4_PDU_TYPE: break;
    }
  }

  UL_info->uci_ind.num_ucis = 0;
}


void handle_nr_ulsch(NR_UL_IND_t *UL_info) {
  if(nfapi_mode == 1) {
    if (UL_info->crc_ind.number_crcs>0) {
      //LOG_D(PHY,"UL_info->crc_ind.crc_indication_body.number_of_crcs:%d CRC_IND:SFN/SF:%d\n", UL_info->crc_ind.crc_indication_body.number_of_crcs, NFAPI_SFNSF2DEC(UL_info->crc_ind.sfn_sf));
      //      oai_nfapi_crc_indication(&UL_info->crc_ind);

      UL_info->crc_ind.number_crcs = 0;
    }

    if (UL_info->rx_ind.number_of_pdus>0) {
      //LOG_D(PHY,"UL_info->rx_ind.number_of_pdus:%d RX_IND:SFN/SF:%d\n", UL_info->rx_ind.rx_indication_body.number_of_pdus, NFAPI_SFNSF2DEC(UL_info->rx_ind.sfn_sf));
      //      oai_nfapi_rx_ind(&UL_info->rx_ind);
      UL_info->rx_ind.number_of_pdus = 0;
    }
  } else {

    if (UL_info->rx_ind.number_of_pdus>0 && UL_info->crc_ind.number_crcs>0) {
      for (int i=0; i<UL_info->rx_ind.number_of_pdus; i++) {
        for (int j=0; j<UL_info->crc_ind.number_crcs; j++) {
          // find crc_indication j corresponding rx_indication i
          LOG_D(PHY,"UL_info->crc_ind.crc_indication_body.crc_pdu_list[%d].rx_ue_information.rnti:%04x UL_info->rx_ind.rx_indication_body.rx_pdu_list[%d].rx_ue_information.rnti:%04x\n", j,
                UL_info->crc_ind.crc_list[j].rnti, i, UL_info->rx_ind.pdu_list[i].rnti);

          if (UL_info->crc_ind.crc_list[j].rnti ==
              UL_info->rx_ind.pdu_list[i].rnti) {
            LOG_D(PHY, "UL_info->crc_ind.crc_indication_body.crc_pdu_list[%d].crc_indication_rel8.crc_flag:%d\n", j, UL_info->crc_ind.crc_list[j].tb_crc_status);

            if (UL_info->crc_ind.crc_list[j].tb_crc_status == 1) { // CRC error indication
              LOG_D(MAC,"Frame %d, Slot %d Calling rx_sdu (CRC error) \n",UL_info->frame,UL_info->slot);

              nr_rx_sdu(UL_info->module_id,
                        UL_info->CC_id,
                        UL_info->rx_ind.sfn, //UL_info->frame,
                        UL_info->rx_ind.slot, //UL_info->slot,
                        UL_info->rx_ind.pdu_list[i].rnti,
                        (uint8_t *)NULL,
                        UL_info->rx_ind.pdu_list[i].pdu_length,
                        UL_info->rx_ind.pdu_list[i].timing_advance,
                        UL_info->rx_ind.pdu_list[i].ul_cqi);
            } else {
              LOG_D(MAC,"Frame %d, Slot %d Calling rx_sdu (CRC ok) \n",UL_info->frame,UL_info->slot);
              nr_rx_sdu(UL_info->module_id,
                        UL_info->CC_id,
                        UL_info->rx_ind.sfn, //UL_info->frame,
                        UL_info->rx_ind.slot, //UL_info->slot,
                        UL_info->rx_ind.pdu_list[i].rnti,
                        UL_info->rx_ind.pdu_list[i].pdu,
                        UL_info->rx_ind.pdu_list[i].pdu_length,
                        UL_info->rx_ind.pdu_list[i].timing_advance,
                        UL_info->rx_ind.pdu_list[i].ul_cqi);
            }
            break;
          }
        } //    for (j=0;j<UL_info->crc_ind.number_crcs;j++)
      } //   for (i=0;i<UL_info->rx_ind.number_of_pdus;i++)

      UL_info->crc_ind.number_crcs=0;
      UL_info->rx_ind.number_of_pdus = 0;
    }
    else if (UL_info->rx_ind.number_of_pdus!=0 || UL_info->crc_ind.number_crcs!=0) {
      LOG_E(PHY,"hoping not to have mis-match between CRC ind and RX ind - hopefully the missing message is coming shortly rx_ind:%d(SFN/SL:%d/%d) crc_ind:%d(SFN/SL:%d/%d) \n",
            UL_info->rx_ind.number_of_pdus, UL_info->rx_ind.sfn, UL_info->rx_ind.slot,
            UL_info->crc_ind.number_crcs, UL_info->rx_ind.sfn, UL_info->rx_ind.slot);
    }
  }
}

void NR_UL_indication(NR_UL_IND_t *UL_info) {
  AssertFatal(UL_info!=NULL,"UL_INFO is null\n");
#ifdef DUMP_FAPI
  dump_ul(UL_info);
#endif
  module_id_t      module_id   = UL_info->module_id;
  int              CC_id       = UL_info->CC_id;
  NR_Sched_Rsp_t   *sched_info = &Sched_INFO[module_id][CC_id];
  NR_IF_Module_t   *ifi        = if_inst[module_id];
  gNB_MAC_INST     *mac        = RC.nrmac[module_id];

  LOG_D(PHY,"SFN/SF:%d%d module_id:%d CC_id:%d UL_info[rach_pdus:%d rx_ind:%d crcs:%d]\n",
        UL_info->frame,UL_info->slot,
        module_id,CC_id, UL_info->rach_ind.number_of_pdus,
        UL_info->rx_ind.number_of_pdus, UL_info->crc_ind.number_crcs);

  if (nfapi_mode != 1) {
    if (ifi->CC_mask==0) {
      ifi->current_frame    = UL_info->frame;
      ifi->current_slot = UL_info->slot;
    } else {
      AssertFatal(UL_info->frame != ifi->current_frame,"CC_mask %x is not full and frame has changed\n",ifi->CC_mask);
      AssertFatal(UL_info->slot != ifi->current_slot,"CC_mask %x is not full and slot has changed\n",ifi->CC_mask);
    }

    ifi->CC_mask |= (1<<CC_id);
  }

  // clear DL/UL info for new scheduling round
  clear_nr_nfapi_information(mac,CC_id,UL_info->frame,UL_info->slot);
  handle_nr_rach(UL_info);
  handle_nr_uci(UL_info, &mac->UE_list.UE_sched_ctrl[0]);
  // clear HI prior to handling ULSCH
  mac->UL_dci_req[CC_id].numPdus = 0;
  handle_nr_ulsch(UL_info);

  if (nfapi_mode != 1) {
    if (ifi->CC_mask == ((1<<MAX_NUM_CCs)-1)) {
      /*
      eNB_dlsch_ulsch_scheduler(module_id,
          (UL_info->frame+((UL_info->slot>(9-sl_ahead))?1:0)) % 1024,
          (UL_info->slot+sl_ahead)%10);
      */
      nfapi_nr_config_request_scf_t *cfg = &mac->config[CC_id];
      int spf = get_spf(cfg);
      gNB_dlsch_ulsch_scheduler(module_id,
				UL_info->frame,
				UL_info->slot,
				(UL_info->frame+((UL_info->slot>(spf-1-sl_ahead))?1:0)) % 1024,
				(UL_info->slot+sl_ahead)%spf);
      
      ifi->CC_mask            = 0;
      sched_info->module_id   = module_id;
      sched_info->CC_id       = CC_id;
      sched_info->frame       = (UL_info->frame + ((UL_info->slot>(spf-1-sl_ahead)) ? 1 : 0)) % 1024;
      sched_info->slot        = (UL_info->slot+sl_ahead)%spf;
      sched_info->DL_req      = &mac->DL_req[CC_id];
      sched_info->UL_dci_req  = &mac->UL_dci_req[CC_id];

      if ((mac->common_channels[CC_id].ServingCellConfigCommon->tdd_UL_DL_ConfigurationCommon==NULL) ||
          (is_nr_UL_slot(mac->common_channels[CC_id].ServingCellConfigCommon,UL_info->slot)>0)) {
	//printf("NR_UL_indication: this is an UL slot. UL_info: frame %d, slot %d. UL_tti_req: frame %d, slot %d\n",UL_info->frame,UL_info->slot,mac->UL_tti_req[CC_id].SFN,mac->UL_tti_req[CC_id].Slot);
        sched_info->UL_tti_req      = &mac->UL_tti_req[CC_id];
      }
      else
        sched_info->UL_tti_req      = NULL;

      sched_info->TX_req      = &mac->TX_req[CC_id];
#ifdef DUMP_FAPI
      dump_dl(sched_info);
#endif

      if (ifi->NR_Schedule_response) {
        AssertFatal(ifi->NR_Schedule_response!=NULL,
                    "nr_schedule_response is null (mod %d, cc %d)\n",
                    module_id,
                    CC_id);
        ifi->NR_Schedule_response(sched_info);
      }

      LOG_D(PHY,"NR_Schedule_response: SFN_SF:%d%d dl_pdus:%d\n",
	    sched_info->frame,
	    sched_info->slot,
	    sched_info->DL_req->dl_tti_request_body.nPDUs);
    }
  }
}

NR_IF_Module_t *NR_IF_Module_init(int Mod_id) {
  AssertFatal(Mod_id<MAX_MODULES,"Asking for Module %d > %d\n",Mod_id,MAX_IF_MODULES);
  LOG_I(PHY,"Installing callbacks for IF_Module - UL_indication\n");

  if (if_inst[Mod_id]==NULL) {
    if_inst[Mod_id] = (NR_IF_Module_t*)malloc(sizeof(NR_IF_Module_t));
    memset((void*)if_inst[Mod_id],0,sizeof(NR_IF_Module_t));

    LOG_I(MAC,"Allocating shared L1/L2 interface structure for instance %d @ %p\n",Mod_id,if_inst[Mod_id]);

    if_inst[Mod_id]->CC_mask=0;
    if_inst[Mod_id]->NR_UL_indication = NR_UL_indication;
    AssertFatal(pthread_mutex_init(&if_inst[Mod_id]->if_mutex,NULL)==0,
                "allocation of if_inst[%d]->if_mutex fails\n",Mod_id);
  }

  return if_inst[Mod_id];
}