// file: csnr_cal_11.cc
//
// this function computes the histogram of the energy of the signal
//

// system include file
//
#include <math.h>

// local include file
//
#include "global_constants.h"
#include "calculate_snr_constants.h"
#include "calculate_snr.h"

// function: calculate_hist_cc
//
// arguments:
//    float**& bin_avgs_a: (output) midpoint of each bin
//    int**& bin_freqs_a: (output) count of each bin
//    float** energy_buffer_a: (input) buffer containing the energy of
//                              each frame
//    int num_energy_vals_a: (input) number of energy points in
//                           the buffer
//    int num_chans_a: (input) number of channels
//    int debug_mode_a: (input) debug mode
//
// return: an int to indicate status
//
// this function calculates the histogram of the energy of a signal
//
//
int calculate_hist_cc (float**& bin_avgs_a, int**& bin_freqs_a,
		       float** energy_buffer_a, int num_energy_vals_a,
		       int num_chans_a, int debug_mode_a) {
  
  // determine the width of the bin
  //
  float* max_value = new float[num_chans_a];
  float* min_value = new float[num_chans_a];
  float* bin_width = new float[num_chans_a];
  
  for (int j = 0; j < num_chans_a; j++) {
    max_value[j] = calculate_max_cc(energy_buffer_a[j], num_energy_vals_a);
    min_value[j] = calculate_min_cc(energy_buffer_a[j], num_energy_vals_a);
    bin_width[j] = (max_value[j] - min_value[j]) / CSNR_NUM_BINS;
  }
  
  // initialize the bins
  //
  for (int j = 0; j < num_chans_a; j++) {
    for (int i = 0; i < CSNR_NUM_BINS; i++) {
      bin_freqs_a[j][i] = 0;
      bin_avgs_a[j][i] = 0;
    }
  }
  
  // determine what goes to which bin
  //
  for (int j = 0; j < num_chans_a; j++) {
    for (int i = 0; i < num_energy_vals_a; i++) {
      
      // limit the data
      //
      float num = energy_buffer_a[j][i];
      
      if (num < min_value[j]) {
	num = min_value[j];
      }
      else if (num > max_value[j]) {
	num = max_value[j];
      }
      
      // calculate which bin the data should go and increment the count
      //
      int index = (int)rint((num - min_value[j]) / bin_width[j]);
      bin_freqs_a[j][index]++;
      bin_avgs_a[j][index] += num;
    }
  }
  
  for (int j = 0; j < num_chans_a; j++) {
    for (int i = 0; i < CSNR_NUM_BINS; i++) {

      if (bin_freqs_a[j][i] == 0) {
	bin_avgs_a[j][i] = bin_width[j] * i - bin_width[j] / 2;
      }
      else {
	bin_avgs_a[j][i] /= bin_freqs_a[j][i];
      }
    }
  }
  
  if (debug_mode_a > DEBUG_BRIEF) {
    for (int j = 0; j < num_chans_a; j++) {
      for (int i = 0; i < CSNR_NUM_BINS; i++) {
	fprintf(stdout, "chan %d :: bin [%d] :: freq = %d value = %.2f\n",
		j, i, bin_freqs_a[j][i], bin_avgs_a[j][i]);
      }
    }
  }
  
  // delete memory
  //
  if (max_value != (float*)NULL) {
    delete [] max_value;
    max_value = (float*)NULL;
  }

  if (min_value != (float*)NULL) {
    delete [] min_value;
    min_value = (float*)NULL;
  }
  
  if (bin_width != (float*)NULL) {
    delete [] bin_width;
    bin_width = (float*)NULL;
  }
      
  // exit gracefully
  //
  return TRUE;
}