/*
 * 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 l2_nr_interface.c
 * \brief layer 2 interface, used to support different RRC sublayer
 * \author Raymond Knopp and Navid Nikaein, WEI-TAI CHEN
 * \date 2010-2014, 2018
 * \version 1.0
 * \company Eurecom, NTUST
 * \email: raymond.knopp@eurecom.fr, kroempa@gmail.com
 */

#include "platform_types.h"
#include "nr_rrc_defs.h"
#include "nr_rrc_extern.h"
#include "common/utils/LOG/log.h"
#include "pdcp.h"
#include "msc.h"
#include "common/ran_context.h"

#include "intertask_interface.h"

#include "NR_MIB.h"
#include "NR_BCCH-BCH-Message.h"

extern RAN_CONTEXT_t RC;

int
nr_rrc_mac_remove_ue(module_id_t mod_idP,
                  rnti_t rntiP){
  // todo
  return 0;
}

//------------------------------------------------------------------------------
uint8_t
nr_rrc_data_req(
  const protocol_ctxt_t   *const ctxt_pP,
  const rb_id_t                  rb_idP,
  const mui_t                    muiP,
  const confirm_t                confirmP,
  const sdu_size_t               sdu_sizeP,
  uint8_t                 *const buffer_pP,
  const pdcp_transmission_mode_t modeP
)
//------------------------------------------------------------------------------
{
  if(sdu_sizeP == 255) {
    LOG_I(RRC,"sdu_sizeP == 255");
    return FALSE;
  }

  MSC_LOG_TX_MESSAGE(
    ctxt_pP->enb_flag ? MSC_RRC_ENB : MSC_RRC_UE,
    ctxt_pP->enb_flag ? MSC_PDCP_ENB : MSC_PDCP_UE,
    buffer_pP,
    sdu_sizeP,
    MSC_AS_TIME_FMT"RRC_DCCH_DATA_REQ UE %x MUI %d size %u",
    MSC_AS_TIME_ARGS(ctxt_pP),
    ctxt_pP->rnti,
    muiP,
    sdu_sizeP);
  MessageDef *message_p;
  // Uses a new buffer to avoid issue with PDCP buffer content that could be changed by PDCP (asynchronous message handling).
  uint8_t *message_buffer;
  message_buffer = itti_malloc (
                     ctxt_pP->enb_flag ? TASK_RRC_ENB : TASK_RRC_UE,
                     ctxt_pP->enb_flag ? TASK_PDCP_ENB : TASK_PDCP_UE,
                     sdu_sizeP);
  memcpy (message_buffer, buffer_pP, sdu_sizeP);
  message_p = itti_alloc_new_message (ctxt_pP->enb_flag ? TASK_RRC_ENB : TASK_RRC_UE, RRC_DCCH_DATA_REQ);
  RRC_DCCH_DATA_REQ (message_p).frame     = ctxt_pP->frame;
  RRC_DCCH_DATA_REQ (message_p).enb_flag  = ctxt_pP->enb_flag;
  RRC_DCCH_DATA_REQ (message_p).rb_id     = rb_idP;
  RRC_DCCH_DATA_REQ (message_p).muip      = muiP;
  RRC_DCCH_DATA_REQ (message_p).confirmp  = confirmP;
  RRC_DCCH_DATA_REQ (message_p).sdu_size  = sdu_sizeP;
  RRC_DCCH_DATA_REQ (message_p).sdu_p     = message_buffer;
  //memcpy (RRC_DCCH_DATA_REQ (message_p).sdu_p, buffer_pP, sdu_sizeP);
  RRC_DCCH_DATA_REQ (message_p).mode      = modeP;
  RRC_DCCH_DATA_REQ (message_p).module_id = ctxt_pP->module_id;
  RRC_DCCH_DATA_REQ (message_p).rnti      = ctxt_pP->rnti;
  RRC_DCCH_DATA_REQ (message_p).eNB_index = ctxt_pP->eNB_index;
  itti_send_msg_to_task (
    ctxt_pP->enb_flag ? TASK_PDCP_ENB : TASK_PDCP_UE,
    ctxt_pP->instance,
    message_p);
  LOG_I(RRC,"sent RRC_DCCH_DATA_REQ to TASK_PDCP_ENB\n");

  /* Hack: only trigger PDCP if in CU, otherwise it is triggered by RU threads
   * Ideally, PDCP would not neet to be triggered like this but react to ITTI
   * messages automatically */
  // if (ctxt_pP->enb_flag && NODE_IS_CU(RC.rrc[ctxt_pP->module_id]->node_type))
  //   pdcp_run(ctxt_pP);

  return TRUE; // TODO should be changed to a CNF message later, currently RRC lite does not used the returned value anyway.
}

int8_t mac_rrc_nr_data_req(const module_id_t Mod_idP,
                           const int         CC_id,
                           const frame_t     frameP,
                           const rb_id_t     Srb_id,
                           const rnti_t      rnti,
                           const uint8_t     Nb_tb,
                           uint8_t *const    buffer_pP ){

  asn_enc_rval_t enc_rval;
  uint8_t Sdu_size = 0;
  uint8_t sfn_msb = (uint8_t)((frameP>>4)&0x3f);
  
#ifdef DEBUG_RRC
  LOG_D(RRC,"[eNB %d] mac_rrc_data_req to SRB ID=%ld\n",Mod_idP,Srb_id);
#endif

  gNB_RRC_INST *rrc;
  rrc_gNB_carrier_data_t *carrier;
  NR_BCCH_BCH_Message_t *mib;
  NR_SRB_INFO * srb_info;
  char payload_size, *payload_pP;
  
  rrc     = RC.nrrrc[Mod_idP];
  carrier = &rrc->carrier;
  mib     = &carrier->mib;
  srb_info = &carrier->Srb0;

  /* MIBCH */
  if( (Srb_id & RAB_OFFSET ) == MIBCH) {
    mib->message.choice.mib->systemFrameNumber.buf[0] = sfn_msb << 2;
    enc_rval = uper_encode_to_buffer(&asn_DEF_NR_BCCH_BCH_Message,
                                     NULL,
                                     (void *)mib,
                                     carrier->MIB,
                                     24);
    LOG_D(NR_RRC,"Encoded MIB for frame %d sfn_msb %d (%p), bits %lu\n",frameP,sfn_msb,carrier->MIB,enc_rval.encoded);
    buffer_pP[0]=carrier->MIB[0];
    buffer_pP[1]=carrier->MIB[1];
    buffer_pP[2]=carrier->MIB[2];
    LOG_D(NR_RRC,"MIB PDU buffer_pP[0]=%x , buffer_pP[1]=%x, buffer_pP[2]=%x\n",buffer_pP[0],buffer_pP[1],buffer_pP[2]);
    AssertFatal (enc_rval.encoded > 0, "ASN1 message encoding failed (%s, %lu)!\n",
                 enc_rval.failed_type->name, enc_rval.encoded);
    return(3);
  }

  /* TODO BCCH SIB1 SIBs */
  if ((Srb_id & RAB_OFFSET ) == BCCH) {
      memcpy(&buffer_pP[0],
             RC.rrc[Mod_idP]->carrier[CC_id].SIB1_MBMS,
             RC.rrc[Mod_idP]->carrier[CC_id].sizeof_SIB1_MBMS);

  }

  /* CCCH */
  struct rrc_gNB_ue_context_s *ue_context_p = NULL;
  if( (Srb_id & RAB_OFFSET ) == CCCH) {
    //struct rrc_eNB_ue_context_s *ue_context_p = rrc_eNB_get_ue_context(RC.rrc[Mod_idP],rnti);
    //if (ue_context_p == NULL) return(0);
    //eNB_RRC_UE_t *ue_p = &ue_context_p->ue_context;
    ue_context_p = rrc_gNB_get_ue_context(RC.nrrrc[Mod_idP], rnti);
    // LOG_I(NR_RRC,"3333 Returning new UE context at %p\n",RC.nrrrc[Mod_idP]);
    // LOG_I(NR_RRC,"4444 Returning new UE context at %p\n",ue_context_p);
    LOG_I(RRC,"[gNB %d] Frame %d CCCH request (Srb_id %ld), ue_context_p %p \n", Mod_idP, frameP, Srb_id, ue_context_p );

    // srb_info=&ue_p->Srb0;

    payload_size = ue_context_p->ue_context.Srb0.Tx_buffer.payload_size;
    // check if data is there for MAC
    if (payload_size > 0) {
      payload_pP = ue_context_p->ue_context.Srb0.Tx_buffer.Payload;
      LOG_D(RRC,"[gNB %d] CCCH (%p) has %d bytes (dest: %p, src %p)\n", Mod_idP, srb_info, payload_size, buffer_pP, payload_pP);
      // Fill buffer
      memcpy((void *)buffer_pP, (void*)payload_pP, payload_size);
      Sdu_size = payload_size;
      ue_context_p->ue_context.Srb0.Tx_buffer.payload_size = 0;
    }
    return Sdu_size;
  }

  return(0);

}

//------------------------------------------------------------------------------
int8_t
nr_mac_rrc_data_ind(
  const module_id_t     module_idP,
  const int             CC_id,
  const frame_t         frameP,
  const sub_frame_t     sub_frameP,
  const int             UE_id,
  const rnti_t          rntiP,
  const rb_id_t         srb_idP,
  const uint8_t        *sduP,
  const sdu_size_t      sdu_lenP,
  const uint8_t         mbsfn_sync_areaP,
  const boolean_t   brOption
)
//--------------------------------------------------------------------------
{
  // if (NODE_IS_DU(RC.nrrrc[module_idP]->node_type)) {
  //   LOG_W(RRC,"[DU %d][RAPROC] Received SDU for CCCH on SRB %ld length %d for UE id %d RNTI %x \n",
  //         module_idP, srb_idP, sdu_lenP, UE_id, rntiP);
  //   /* do ITTI message */
  //   DU_send_INITIAL_UL_RRC_MESSAGE_TRANSFER(
  //     module_idP,
  //     CC_id,
  //     UE_id,
  //     rntiP,
  //     sduP,
  //     sdu_lenP
  //   );
  //   return(0);
  // }

  //SRB_INFO *Srb_info;
  protocol_ctxt_t ctxt;
  sdu_size_t      sdu_size = 0;
  /* for no gcc warnings */
  (void)sdu_size;
  /*
  int si_window;
   */
  PROTOCOL_CTXT_SET_BY_MODULE_ID(&ctxt, module_idP, GNB_FLAG_YES, rntiP, frameP, sub_frameP,0);
  if((srb_idP & RAB_OFFSET) == CCCH) {
    LOG_D(RRC, "[eNB %d] Received SDU for CCCH on SRB %ld\n", module_idP, srb_idP);
    ctxt.brOption = brOption;

    /*Srb_info = &RC.rrc[module_idP]->carrier[CC_id].Srb0;
    if (sdu_lenP > 0) {
      memcpy(Srb_info->Rx_buffer.Payload,sduP,sdu_lenP);
      Srb_info->Rx_buffer.payload_size = sdu_lenP;
      rrc_eNB_decode_ccch(&ctxt, Srb_info, CC_id);
    }*/
    if (sdu_lenP > 0)  nr_rrc_gNB_decode_ccch(&ctxt, sduP, sdu_lenP, CC_id);
  }

  return(0);
}