/**
 *
 * \section COPYRIGHT
 *
 * Copyright 2013-2015 Software Radio Systems Limited
 *
 * \section LICENSE
 *
 * This file is part of the srsLTE library.
 *
 * srsLTE is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * srsLTE is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * A copy of the GNU Affero General Public License can be found in
 * the LICENSE file in the top-level directory of this distribution
 * and at http://www.gnu.org/licenses/.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <sys/time.h>

#include "srslte/srslte.h"

srslte_cell_t cell = {
  6,            // nof_prb
  1,            // nof_ports
  0,            // cell_id
  SRSLTE_CP_NORM,       // cyclic prefix
  SRSLTE_PHICH_R_1_6,          // PHICH resources      
  SRSLTE_PHICH_NORM    // PHICH length
};

uint32_t cfi = 2;
uint32_t tbs = 0;
uint32_t subframe = 1;
srslte_mod_t modulation = SRSLTE_MOD_QPSK;
uint32_t rv_idx = 0;
uint32_t L_prb = 2; 
uint32_t n_prb = 0; 
int freq_hop = -1; 
int riv = -1; 
uint32_t mcs_idx = 0; 

void usage(char *prog) {
  printf("Usage: %s [csrnfvmtLNF] -m MCS \n", prog);
  printf("\t-m MCS index [Default %d]\n", mcs_idx);
  printf("\t-c cell id [Default %d]\n", cell.id);
  printf("\t-s subframe [Default %d]\n", subframe);
  printf("\t-L L_prb [Default %d]\n", L_prb);
  printf("\t-N n_prb [Default %d]\n", n_prb);
  printf("\t-F frequency hopping [Default %d]\n", freq_hop);
  printf("\t-R RIV [Default %d]\n", riv);
  printf("\t-r rv_idx [Default %d]\n", rv_idx);
  printf("\t-f cfi [Default %d]\n", cfi);
  printf("\t-n cell.nof_prb [Default %d]\n", cell.nof_prb);
  printf("\t-v [set srslte_verbose to debug, default none]\n");
}

void parse_args(int argc, char **argv) {
  int opt;
  while ((opt = getopt(argc, argv, "cnfvmtsrLNFR")) != -1) {
    switch(opt) {
    case 'm':
      mcs_idx = atoi(argv[optind]);
      break;
    case 's':
      subframe = atoi(argv[optind]);
      break;
    case 'L':
      L_prb = atoi(argv[optind]);
      break;
    case 'N':
      n_prb = atoi(argv[optind]);
      break;
    case 'R':
      riv = atoi(argv[optind]);
      break;
    case 'F':
      freq_hop = atoi(argv[optind]);
      break;
    case 'r':
      rv_idx = atoi(argv[optind]);
      break;
    case 'n':
      cell.nof_prb = atoi(argv[optind]);
      break;
    case 'c':
      cell.id = atoi(argv[optind]);
      break;
    case 'v':
      srslte_verbose++;
      break;
    default:
      usage(argv[0]);
      exit(-1);
    }
  }
}

int main(int argc, char **argv) {
  srslte_pusch_t pusch;
  uint8_t *data = NULL;
  cf_t *sf_symbols = NULL;
  cf_t *ce = NULL; 
  int ret = -1;
  struct timeval t[3];
  srslte_pusch_cfg_t cfg; 
  srslte_softbuffer_tx_t softbuffer_tx;
  srslte_softbuffer_rx_t softbuffer_rx; 
  
  parse_args(argc,argv);

  bzero(&cfg, sizeof(srslte_pusch_cfg_t));

  srslte_ra_ul_dci_t dci;
  dci.freq_hop_fl = freq_hop;
  if (riv < 0) {
    dci.type2_alloc.L_crb = L_prb; 
    dci.type2_alloc.RB_start = n_prb;    
  } else {
    dci.type2_alloc.riv = riv;
  }
  dci.mcs_idx = mcs_idx;
  
  srslte_ra_ul_grant_t grant; 
  if (srslte_ra_ul_dci_to_grant(&dci, cell.nof_prb, 0, &grant, 0)) {
    fprintf(stderr, "Error computing resource allocation\n");
    return ret;
  }
      
  srslte_pusch_hopping_cfg_t ul_hopping; 
  ul_hopping.n_sb = 1; 
  ul_hopping.hopping_offset = 0;
  ul_hopping.hop_mode = SRSLTE_PUSCH_HOP_MODE_INTER_SF;
  
  if (srslte_pusch_init(&pusch, cell)) {
    fprintf(stderr, "Error creating PDSCH object\n");
    goto quit;
  }
  
  /* Configure PUSCH */
    
  printf("Encoding rv_idx=%d\n",rv_idx);
  
  srslte_uci_cfg_t uci_cfg; 
  uci_cfg.I_offset_cqi = 6; 
  uci_cfg.I_offset_ri = 2; 
  uci_cfg.I_offset_ack = 4; 

  if (srslte_pusch_cfg(&pusch, &cfg, &grant, &uci_cfg, &ul_hopping, NULL, subframe, 0, 0)) {
    fprintf(stderr, "Error configuring PDSCH\n");
    exit(-1);
  }
  
  srslte_pusch_set_rnti(&pusch, 1234);
  
  srslte_uci_data_t uci_data_tx; 
  srslte_uci_data_t uci_data_rx; 
  bzero(&uci_data_tx, sizeof(srslte_uci_data_t));
  uci_data_tx.uci_cqi_len = 4; 
  uci_data_tx.uci_ri_len = 0; 
  uci_data_tx.uci_ack_len = 0; 
  memcpy(&uci_data_rx, &uci_data_tx, sizeof(srslte_uci_data_t));
    
  for (uint32_t i=0;i<20;i++) {
    uci_data_tx.uci_cqi [i] = 1;
  }
  uci_data_tx.uci_ri = 1; 
  uci_data_tx.uci_ack = 1; 

  uint32_t nof_re = SRSLTE_NRE*cell.nof_prb*2*SRSLTE_CP_NSYMB(cell.cp);
  sf_symbols = srslte_vec_malloc(sizeof(cf_t) * nof_re);
  if (!sf_symbols) {
    perror("malloc");
    goto quit;
  }
  
  data = srslte_vec_malloc(sizeof(uint8_t) * cfg.grant.mcs.tbs);
  if (!data) {
    perror("malloc");
    goto quit;
  }
  
  for (uint32_t i=0;i<cfg.grant.mcs.tbs/8;i++) {
    data[i] = 1;
  }

  if (srslte_softbuffer_tx_init(&softbuffer_tx, 100)) {
    fprintf(stderr, "Error initiating soft buffer\n");
    goto quit;
  }
  if (srslte_softbuffer_rx_init(&softbuffer_rx, 100)) {
    fprintf(stderr, "Error initiating soft buffer\n");
    goto quit;
  }
  
  uint32_t ntrials = 100; 

  if (srslte_pusch_uci_encode(&pusch, &cfg, &softbuffer_tx, data, uci_data_tx, sf_symbols)) {
    fprintf(stderr, "Error encoding TB\n");
    exit(-1);
  }
  if (rv_idx > 0) {
    cfg.rv = rv_idx; 
    if (srslte_pusch_uci_encode(&pusch, &cfg, &softbuffer_tx, data, uci_data_tx, sf_symbols)) {
      fprintf(stderr, "Error encoding TB\n");
      exit(-1);
    }
  }

  ce = srslte_vec_malloc(sizeof(cf_t) * SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp));
  if (!ce) {
    perror("srslte_vec_malloc");
    goto quit;
  }
  for (int j=0;j<SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp);j++) {
    ce[j] = 1;
  }
  
  gettimeofday(&t[1], NULL);
  int r = srslte_pusch_uci_decode(&pusch, &cfg, &softbuffer_rx, sf_symbols, ce, 0, data, &uci_data_rx);
  gettimeofday(&t[2], NULL);
  get_time_interval(t);
  if (r) {
    printf("Error decoding\n");
    ret = -1;
  } else {
    ret = 0;
    printf("DECODED OK in %d:%d (TBS: %d bits, TX: %.2f Mbps, Processing: %.2f Mbps)\n", (int) t[0].tv_sec, 
           (int) t[0].tv_usec/ntrials, 
           cfg.grant.mcs.tbs,
           (float) cfg.grant.mcs.tbs/1000,
           (float) cfg.grant.mcs.tbs/t[0].tv_usec*ntrials);    
  }
  if (uci_data_tx.uci_ack_len) {
    if (uci_data_tx.uci_ack != uci_data_rx.uci_ack) {
      printf("UCI ACK bit error: %d != %d\n", uci_data_tx.uci_ack, uci_data_rx.uci_ack);
    }
  }
  if (uci_data_tx.uci_ri_len) {
    if (uci_data_tx.uci_ri != uci_data_rx.uci_ri) {
      printf("UCI RI bit error: %d != %d\n", uci_data_tx.uci_ri, uci_data_rx.uci_ri);
    }
  }
  if (uci_data_tx.uci_cqi_len) {
    printf("cqi_tx=");
    srslte_vec_fprint_b(stdout, uci_data_tx.uci_cqi, uci_data_tx.uci_cqi_len);
    printf("cqi_rx=");
    srslte_vec_fprint_b(stdout, uci_data_rx.uci_cqi, uci_data_rx.uci_cqi_len);
  }

quit:
  srslte_pusch_free(&pusch);
  srslte_softbuffer_tx_free(&softbuffer_tx);
  
  if (sf_symbols) {
    free(sf_symbols);
  }
  if (data) {
    free(data);
  }
  if (ce) {
    free(ce);
  }
  if (ret) {
    printf("Error\n");
  } else {
    printf("Ok\n");
  }
  exit(ret);
}