/*****************************************************************************
#                                                                            *
# Copyright 2019 AT&T Intellectual Property                                  *
# Copyright 2019 Nokia                                                       *
# Copyright (c) 2020 Samsung Electronics Co., Ltd. All Rights Reserved.      *
#                                                                            *
# Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0                            *
#                                                                            *
# 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.                                             *
#                                                                            *
******************************************************************************/
#include "e2ap_message_handler.hpp"

//#include <iostream>
//#include <vector>

#include "encode_e2apv1.hpp"


#include <unistd.h>

void e2ap_handle_sctp_data(int &socket_fd, sctp_buffer_t &data, bool xmlenc)
{
  fprintf(stderr, "in e2ap_handle_sctp_data()\n");
  //decode the data into E2AP-PDU
  E2AP_PDU_t* pdu = (E2AP_PDU_t*)calloc(1, sizeof(E2AP_PDU));
  ASN_STRUCT_RESET(asn_DEF_E2AP_PDU, pdu);

  fprintf(stderr, "decoding...\n");

  asn_transfer_syntax syntax;


  syntax = ATS_ALIGNED_BASIC_PER;


  fprintf(stderr, "full buffer\n%s\n", data.buffer);
  //  e2ap_asn1c_decode_pdu(pdu, data.buffer, data.len);

  auto rval = asn_decode(nullptr, syntax, &asn_DEF_E2AP_PDU, (void **) &pdu,
		    data.buffer, data.len);


  int index = (int)pdu->present;
  fprintf(stderr, "length of data %d\n", rval.consumed);
  fprintf(stderr, "result %d\n", rval.code);
  fprintf(stderr, "index is %d\n", index);

  fprintf(stderr, "showing xer of data\n");

  xer_fprint(stderr, &asn_DEF_E2AP_PDU, pdu);

  int procedureCode = e2ap_asn1c_get_procedureCode(pdu);
  index = (int)pdu->present;

  LOG_D("[E2AP] Unpacked E2AP-PDU: index = %d, procedureCode = %d\n",
                            index, procedureCode);

  switch(procedureCode)
    {

    case ProcedureCode_id_E2setup:
      switch(index)
	{
        case E2AP_PDU_PR_initiatingMessage:
	  e2ap_handle_E2SetupRequest(pdu, socket_fd);
          LOG_I("[E2AP] Received SETUP-REQUEST");
          break;

        case E2AP_PDU_PR_successfulOutcome:
          LOG_I("[E2AP] Received SETUP-RESPONSE-SUCCESS");
          break;

        case E2AP_PDU_PR_unsuccessfulOutcome:
          LOG_I("[E2AP] Received SETUP-RESPONSE-FAILURE");
          break;

        default:
          LOG_E("[E2AP] Invalid message index=%d in E2AP-PDU", index);
          break;
	}
      break;

    case ProcedureCode_id_Reset: //reset = 7
      switch(index)
	{
        case E2AP_PDU_PR_initiatingMessage:
          LOG_I("[E2AP] Received RESET-REQUEST");
          break;

        case E2AP_PDU_PR_successfulOutcome:
          break;

        case E2AP_PDU_PR_unsuccessfulOutcome:
          break;

        default:
          LOG_E("[E2AP] Invalid message index=%d in E2AP-PDU", index);
          break;
	}
      break;

    case ProcedureCode_id_RICindication: // 205
      switch(index)
	{
        case E2AP_PDU_PR_initiatingMessage: //initiatingMessage
          LOG_I("[E2AP] Received RIC-INDICATION-REQUEST");
          // e2ap_handle_RICSubscriptionRequest(pdu, socket_fd);
          break;
        case E2AP_PDU_PR_successfulOutcome:
          LOG_I("[E2AP] Received RIC-INDICATION-RESPONSE");
          break;

        case E2AP_PDU_PR_unsuccessfulOutcome:
          LOG_I("[E2AP] Received RIC-INDICATION-FAILURE");
          break;

        default:
          LOG_E("[E2AP] Invalid message index=%d in E2AP-PDU %d", index,
                                    (int)ProcedureCode_id_RICindication);
          break;
	}
      break;

      case ProcedureCode_id_RICserviceQuery:
        switch (index)
          {
            case E2AP_PDU_PR_initiatingMessage:
            LOG_I("[E2AP] Received RIC-Service-Query")
            e2ap_handle_E2SeviceUpdate(pdu, socket_fd);
            break;

            default:
              LOG_E("[E2AP] Invalid message index=%d in E2AP-PDU %d", index,
                                      (int)ProcedureCode_id_RICserviceQuery);
            break;
          }
        break;

      case ProcedureCode_id_RICserviceUpdate:
        switch (index)
          {
            case E2AP_PDU_PR_successfulOutcome:
            LOG_I("[E2AP] Received RIC-SERVICE-UPDATE-SUCCESS")
            break;

            case E2AP_PDU_PR_unsuccessfulOutcome:
            LOG_I("[E2AP] Received RIC-SERVICE-UPDATE-FAILURE")
            break;

            default:
              LOG_E("[E2AP] Invalid message index=%d in E2AP-PDU %d", index,
                                      (int)ProcedureCode_id_RICserviceUpdate);
            break;
          }
        break;

    default:

      LOG_E("[E2AP] No available handler for procedureCode=%d", procedureCode);

      break;
    }
}

void e2ap_handle_E2SeviceUpdate(E2AP_PDU_t* pdu, int &socket_fd) {

auto buffer_size = MAX_SCTP_BUFFER;
  unsigned char buffer[MAX_SCTP_BUFFER];
  E2AP_PDU_t* pdu = (E2AP_PDU_t*)calloc(1,sizeof(E2AP_PDU));
  generate_e2apv1_service_update(pdu);

  printf("After generating e2setup req\n");

  xer_fprint(stderr, &asn_DEF_E2AP_PDU, pdu);

  printf("After XER Encoding\n");

  sctp_buffer_t data;

  char *error_buf = (char*)calloc(300, sizeof(char));
  size_t errlen;

  asn_check_constraints(&asn_DEF_E2AP_PDU, pdu, error_buf, &errlen);
  printf("error length %d\n", errlen);
  printf("error buf %s\n", error_buf);

  auto er = asn_encode_to_buffer(nullptr, ATS_ALIGNED_BASIC_PER, &asn_DEF_E2AP_PDU, pdu, buffer, buffer_size);
  //auto er = asn_encode_to_buffer(nullptr, ATS_BASIC_XER, &asn_DEF_E2AP_PDU, pdu_setup, buffer, buffer_size);
  data.len = er.encoded;
  fprintf(stderr, "er encoded is %d\n", er.encoded);

  memcpy(data.buffer, buffer, er.encoded);

  //send response data over sctp
  if(sctp_send_data(socket_fd, data) > 0) {
    LOG_I("[SCTP] Sent E2-SERVICE-UPDATE");
  } else {
    LOG_E("[SCTP] Unable to send E2-SERVICE-UPDATE to peer");
  }
}

void e2ap_handle_E2SetupRequest(E2AP_PDU_t* pdu, int &socket_fd) {


  E2AP_PDU_t* res_pdu = (E2AP_PDU_t*)calloc(1, sizeof(E2AP_PDU));
  generate_e2apv1_setup_response(res_pdu);


  LOG_D("[E2AP] Created E2-SETUP-RESPONSE");

  e2ap_asn1c_print_pdu(res_pdu);


  auto buffer_size = MAX_SCTP_BUFFER;
  unsigned char buffer[MAX_SCTP_BUFFER];

  sctp_buffer_t data;
  auto er = asn_encode_to_buffer(nullptr, ATS_BASIC_XER, &asn_DEF_E2AP_PDU, res_pdu, buffer, buffer_size);

  data.len = er.encoded;
  fprintf(stderr, "er encoded is %d\n", er.encoded);

  //data.len = e2ap_asn1c_encode_pdu(res_pdu, &buf);
  memcpy(data.buffer, buffer, er.encoded);

  //send response data over sctp
  if(sctp_send_data(socket_fd, data) > 0) {
    LOG_I("[SCTP] Sent E2-SETUP-RESPONSE");
  } else {
    LOG_E("[SCTP] Unable to send E2-SETUP-RESPONSE to peer");
  }

  sleep(5);

  //Sending Subscription Request

  E2AP_PDU_t* pdu_sub = (E2AP_PDU_t*)calloc(1,sizeof(E2AP_PDU));

  generate_e2apv1_subscription_request(pdu_sub);

  xer_fprint(stderr, &asn_DEF_E2AP_PDU, pdu_sub);

  auto buffer_size2 = MAX_SCTP_BUFFER;
  unsigned char buffer2[MAX_SCTP_BUFFER];

  sctp_buffer_t data2;

  auto er2 = asn_encode_to_buffer(nullptr, ATS_ALIGNED_BASIC_PER, &asn_DEF_E2AP_PDU, pdu_sub, buffer2, buffer_size2);

  data2.len = er2.encoded;
  memcpy(data2.buffer, buffer2, er2.encoded);

  fprintf(stderr, "er encded is %d\n", er2.encoded);

  if(sctp_send_data(socket_fd, data2) > 0) {
    LOG_I("[SCTP] Sent E2-SUBSCRIPTION-REQUEST");
  } else {
    LOG_E("[SCTP] Unable to send E2-SUBSCRIPTION-REQUEST to peer");
  }


}


void e2ap_handle_RICSubscriptionRequest(E2AP_PDU_t* pdu, int &socket_fd)
{

  //Send back Subscription Success Response

  E2AP_PDU_t* pdu_resp = (E2AP_PDU_t*)calloc(1,sizeof(E2AP_PDU));

  generate_e2apv1_subscription_response(pdu_resp, pdu);

  fprintf(stderr, "Subscription Response\n");

  xer_fprint(stderr, &asn_DEF_E2AP_PDU, pdu_resp);

  auto buffer_size2 = MAX_SCTP_BUFFER;
  unsigned char buffer2[MAX_SCTP_BUFFER];

  sctp_buffer_t data2;

  auto er2 = asn_encode_to_buffer(nullptr, ATS_ALIGNED_BASIC_PER, &asn_DEF_E2AP_PDU, pdu_resp, buffer2, buffer_size2);
  data2.len = er2.encoded;

  fprintf(stderr, "er encded is %d\n", er2.encoded);

  memcpy(data2.buffer, buffer2, er2.encoded);

  if(sctp_send_data(socket_fd, data2) > 0) {
    LOG_I("[SCTP] Sent RIC-SUBSCRIPTION-RESPONSE");
  } else {
    LOG_E("[SCTP] Unable to send RIC-SUBSCRIPTION-RESPONSE to peer");
  }


  //Send back an Indication

  E2AP_PDU_t* pdu_ind = (E2AP_PDU_t*)calloc(1,sizeof(E2AP_PDU));

  generate_e2apv1_indication_request(pdu_ind);

  xer_fprint(stderr, &asn_DEF_E2AP_PDU, pdu_ind);

  auto buffer_size = MAX_SCTP_BUFFER;
  unsigned char buffer[MAX_SCTP_BUFFER];

  sctp_buffer_t data;

  auto er = asn_encode_to_buffer(nullptr, ATS_ALIGNED_BASIC_PER, &asn_DEF_E2AP_PDU, pdu_ind, buffer, buffer_size);
  data.len = er.encoded;

  fprintf(stderr, "er encded is %d\n", er.encoded);

  memcpy(data.buffer, buffer, er.encoded);

  if(sctp_send_data(socket_fd, data) > 0) {
    LOG_I("[SCTP] Sent RIC-INDICATION-REQUEST");
  } else {
    LOG_E("[SCTP] Unable to send RIC-INDICATION-REQUEST to peer");
  }

}