// FFT

#pragma once

#include <complex>
#include <vector>

namespace RIT {

class FFT {
private:
	int mSize;
	std::vector<int> order;
	std::vector<std::complex<double>> expLUT;

	bool mFlagHalfOnly;

public:
	FFT(int size, bool halfOnly = false);
	std::vector<std::complex<double>> operator()(const std::vector<std::complex<double>> &v);

	FFT& SetHalfOnly(bool enable);

private:
	int bitreverse(int i);

	void reorder(const std::vector<std::complex<double>>& src, std::vector<std::complex<double>>& dst);
	void fft_recursive(std::vector<std::complex<double>>::iterator X, int N);
	void fft_half(std::vector<std::complex<double>>::iterator X, int N);
}; // class FFT

std::vector<double> magnitudes(std::vector<std::complex<double>>& v);

} // namespace RIT