/* -*- c++ -*- */
/* Copyright 2012 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 <gnuradio/digital/ofdm_equalizer_static.h>

namespace gr {
namespace digital {

ofdm_equalizer_static::sptr
ofdm_equalizer_static::make(int fft_len,
                            const std::vector<std::vector<int>>& occupied_carriers,
                            const std::vector<std::vector<int>>& pilot_carriers,
                            const std::vector<std::vector<gr_complex>>& pilot_symbols,
                            int symbols_skipped,
                            bool input_is_shifted)
{
    return ofdm_equalizer_static::sptr(new ofdm_equalizer_static(fft_len,
                                                                 occupied_carriers,
                                                                 pilot_carriers,
                                                                 pilot_symbols,
                                                                 symbols_skipped,
                                                                 input_is_shifted));
}

ofdm_equalizer_static::ofdm_equalizer_static(
    int fft_len,
    const std::vector<std::vector<int>>& occupied_carriers,
    const std::vector<std::vector<int>>& pilot_carriers,
    const std::vector<std::vector<gr_complex>>& pilot_symbols,
    int symbols_skipped,
    bool input_is_shifted)
    : ofdm_equalizer_1d_pilots(fft_len,
                               occupied_carriers,
                               pilot_carriers,
                               pilot_symbols,
                               symbols_skipped,
                               input_is_shifted)
{
}


ofdm_equalizer_static::~ofdm_equalizer_static() {}


void ofdm_equalizer_static::equalize(gr_complex* frame,
                                     int n_sym,
                                     const std::vector<gr_complex>& initial_taps,
                                     const std::vector<tag_t>& tags)
{
    d_channel_state = initial_taps;

    for (int i = 0; i < n_sym; i++) {
        for (int k = 0; k < d_fft_len; k++) {
            if (!d_occupied_carriers[k]) {
                continue;
            }
            if (!d_pilot_carriers.empty() && d_pilot_carriers[d_pilot_carr_set][k]) {
                d_channel_state[k] =
                    frame[i * d_fft_len + k] / d_pilot_symbols[d_pilot_carr_set][k];
                frame[i * d_fft_len + k] = d_pilot_symbols[d_pilot_carr_set][k];
            } else {
                frame[i * d_fft_len + k] /= d_channel_state[k];
            }
        }
        if (!d_pilot_carriers.empty()) {
            d_pilot_carr_set = (d_pilot_carr_set + 1) % d_pilot_carriers.size();
        }
    }
}

} /* namespace digital */
} /* namespace gr */
