#include <eqpalg/utility/normalize.h>

namespace utility {
int normalize_min_max(std::vector<double>* vec_ptr,
                      dlib::running_stats<double> rs) {
  double base = rs.min();
  double top = rs.max();
  double diff = top - base;
  std::for_each(vec_ptr->begin(), vec_ptr->end(),
                [&](double& value) { value = (value - base) / diff; });
  return 0;
}

int normalize_z_score(std::vector<double>* vec_ptr,
                      dlib::running_stats<double> rs) {
  double mean = rs.mean();
  double stddev = rs.stddev();
  std::for_each(vec_ptr->begin(), vec_ptr->end(),
                [&](double& value) { value = (value - mean) / stddev; });
  return 0;
}

double normalize_min_max(double x, dlib::running_stats<double> rs) {
  double base = rs.min();
  double top = rs.max();
  double diff = top - base;
  return (x - base) / diff;
}

double normalize_z_score(double x, dlib::running_stats<double> rs) {
  return (x - rs.mean()) / rs.stddev();
}

double denormalize_z_score(double invert_x, dlib::running_stats<double> rs) {
  return (invert_x * rs.stddev()) + rs.mean();
}

double denormalize_min_max(double invert_x, dlib::running_stats<double> rs) {
  double base = rs.min();
  double top = rs.max();
  double diff = top - base;
  return (invert_x * diff) + base;
}
}  // namespace utility