#ifndef SRC_LOCK_IN_H_
#define SRC_LOCK_IN_H_
#include <iostream>
#include <vector>

namespace mri {
  class LockIn {
  public:
    template<class T> inline T pow2(const T value) {return value*value;}
    const double PI_=3.14159265358979323846;
    void Analyse(const std::vector<double> &signal,double period_ms,
                 const std::vector<double> &timesteps,
                 int samples_per_period,
                 std::vector<double> &avg_sin,
                 std::vector<double> &avg_cos);
  private:
    std::vector<double> lockin_sin_, lockin_cos_;
    std::vector<double> mul_sin_, mul_cos_;
    std::vector<double> mag_sin_, mag_cos_;
    double period_ms_, omega_;
    unsigned long total_samples_;
    int samples_per_period_;
    void GenerateSinCos(const std::vector<double> &timesteps);
    void Multiply(const std::vector<double> &signal);
    void FilterLowPassFirstOrder();
    void FilterLowPassForthOrder();
    void FilterLowPassPeriodAverage();
    void FilterLowPassWindowedSinc();

  };  // end of class LockIn
}  // end of namespace mri
#endif  // SRC_LOCK_IN_H_