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

/*

 * Copyright 2004,2006 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.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <gr_adaptive_fir_ccf.h>

#include <gr_io_signature.h>

gr_adaptive_fir_ccf::gr_adaptive_fir_ccf(const char *name, int decimation, const std::vector<float> &taps)

  : gr_sync_decimator (name,

                       gr_make_io_signature (1, 1, sizeof(gr_complex)),

                       gr_make_io_signature (1, 1, sizeof(gr_complex)),

                       decimation),

    d_updated(false)

{

  d_taps = taps;

  set_history(d_taps.size());

}

void gr_adaptive_fir_ccf::set_taps(const std::vector<float> &taps)

{

  d_new_taps = taps;

  d_updated = true;

}

int gr_adaptive_fir_ccf::work(int noutput_items,

                              gr_vector_const_void_star &input_items,

                              gr_vector_void_star &output_items)

{

  gr_complex *in = (gr_complex *)input_items[0];

  gr_complex *out = (gr_complex *)output_items[0];

  if (d_updated) {

    d_taps = d_new_taps;

    set_history(d_taps.size());

    d_updated = false;

    return 0;                     // history requirements may have changed.

  }

  int j = 0, k, l = d_taps.size();

  for (int i = 0; i < noutput_items; i++) {

    // Generic dot product of d_taps[] and in[]

    gr_complex sum(0.0, 0.0);

    for (k = 0; k < l; k++)

      sum += d_taps[l-k-1]*in[j+k];

    out[i] = sum;

    // Adjust taps

    d_error = error(sum);

    for (k = 0; k < l; k++) {

      //printf("%f ", d_taps[k]);

      update_tap(d_taps[l-k-1], in[j+k]);

    }

    //printf("\n");

    j += decimation();

  }

  return noutput_items;

}