/* -*- c++ -*- */

/*

 * Copyright 2005 Free Software Foundation, Inc.

 * 

 * This file is part of GNU Radio

 * 

 * GNU Radio is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3, or (at your option)

 * any later version.

 * 

 * GNU Radio 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 General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with GNU Radio; see the file COPYING.  If not, write to

 * the Free Software Foundation, Inc., 51 Franklin Street,

 * Boston, MA 02110-1301, USA.

 */

#ifndef INCLUDED_GR_FFT_FILTER_CCC_H

#define INCLUDED_GR_FFT_FILTER_CCC_H

#include <gr_sync_decimator.h>

class gr_fft_filter_ccc;

typedef boost::shared_ptr<gr_fft_filter_ccc> gr_fft_filter_ccc_sptr;

gr_fft_filter_ccc_sptr gr_make_fft_filter_ccc (int decimation, const std::vector<gr_complex> &taps);

class gr_fir_ccc;

class gri_fft_complex;

/*!

 * \brief Fast FFT filter with gr_complex input, gr_complex output and gr_complex taps

 * \ingroup filter

 */

class gr_fft_filter_ccc : public gr_sync_decimator

{

 private:

  friend gr_fft_filter_ccc_sptr gr_make_fft_filter_ccc (int decimation, const std::vector<gr_complex> &taps);

  int                           d_ntaps;

  int                           d_nsamples;

  int                           d_fftsize;                // fftsize = ntaps + nsamples - 1

  gri_fft_complex          *d_fwdfft;                // forward "plan"

  gri_fft_complex          *d_invfft;                // inverse "plan"

  std::vector<gr_complex>  d_tail;                // state carried between blocks for overlap-add

  std::vector<gr_complex>  d_xformed_taps;        // Fourier xformed taps

  std::vector<gr_complex>  d_new_taps;

  bool                           d_updated;

  /*!

   * Construct a FFT filter with the given taps

   *

   * \param decimation        >= 1

   * \param taps        complex filter taps

   */

  gr_fft_filter_ccc (int decimation, const std::vector<gr_complex> &taps);

  void compute_sizes(int ntaps);

  int tailsize() const { return d_ntaps - 1; }

  void actual_set_taps (const std::vector<gr_complex> &taps);

 public:

  ~gr_fft_filter_ccc ();

  void set_taps (const std::vector<gr_complex> &taps);

  int work (int noutput_items,

            gr_vector_const_void_star &input_items,

            gr_vector_void_star &output_items);

};

#endif /* INCLUDED_GR_FFT_FILTER_CCC_H */