/* -*- c++ -*- */
/*
 * Copyright 2013, 2018 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 "ofdm_carrier_allocator_cvc_impl.h"
#include <gnuradio/io_signature.h>

namespace gr {
namespace digital {

ofdm_carrier_allocator_cvc::sptr ofdm_carrier_allocator_cvc::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,
    const std::vector<std::vector<gr_complex>>& sync_words,
    const std::string& len_tag_key,
    const bool output_is_shifted)
{
    return gnuradio::get_initial_sptr(
        new ofdm_carrier_allocator_cvc_impl(fft_len,
                                            occupied_carriers,
                                            pilot_carriers,
                                            pilot_symbols,
                                            sync_words,
                                            len_tag_key,
                                            output_is_shifted));
}

ofdm_carrier_allocator_cvc_impl::ofdm_carrier_allocator_cvc_impl(
    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,
    const std::vector<std::vector<gr_complex>>& sync_words,
    const std::string& len_tag_key,
    const bool output_is_shifted)
    : tagged_stream_block("ofdm_carrier_allocator_cvc",
                          io_signature::make(1, 1, sizeof(gr_complex)),
                          io_signature::make(1, 1, sizeof(gr_complex) * fft_len),
                          len_tag_key),
      d_fft_len(fft_len),
      d_occupied_carriers(occupied_carriers),
      d_pilot_carriers(pilot_carriers),
      d_pilot_symbols(pilot_symbols),
      d_sync_words(sync_words),
      d_symbols_per_set(0),
      d_output_is_shifted(output_is_shifted)
{
    // Sanity checks
    // If that is is null, the input is wrong -> force user to use ((),) in python
    if (d_occupied_carriers.empty()) {
        throw std::invalid_argument(
            "Occupied carriers must be of type vector of vector i.e. ((),).");
    }
    for (unsigned i = 0; i < d_occupied_carriers.size(); i++) {
        for (unsigned j = 0; j < d_occupied_carriers[i].size(); j++) {
            if (occupied_carriers[i][j] < 0) {
                d_occupied_carriers[i][j] += d_fft_len;
            }
            if (d_occupied_carriers[i][j] > d_fft_len || d_occupied_carriers[i][j] < 0) {
                throw std::invalid_argument("data carrier index out of bounds");
            }
            if (d_output_is_shifted) {
                d_occupied_carriers[i][j] =
                    (d_occupied_carriers[i][j] + fft_len / 2) % fft_len;
            }
        }
    }
    if (d_pilot_carriers.empty()) {
        throw std::invalid_argument(
            "Pilot carriers must be of type vector of vector i.e. ((),).");
    }
    for (unsigned i = 0; i < d_pilot_carriers.size(); i++) {
        for (unsigned j = 0; j < d_pilot_carriers[i].size(); j++) {
            if (d_pilot_carriers[i][j] < 0) {
                d_pilot_carriers[i][j] += d_fft_len;
            }
            if (d_pilot_carriers[i][j] > d_fft_len || d_pilot_carriers[i][j] < 0) {
                throw std::invalid_argument("pilot carrier index out of bounds");
            }
            if (d_output_is_shifted) {
                d_pilot_carriers[i][j] = (d_pilot_carriers[i][j] + fft_len / 2) % fft_len;
            }
        }
    }
    if (d_pilot_symbols.empty()) {
        throw std::invalid_argument(
            "Pilot symbols must be of type vector of vector i.e. ((),).");
    }
    for (unsigned i = 0; i < std::max(d_pilot_carriers.size(), d_pilot_symbols.size());
         i++) {
        if (d_pilot_carriers[i % d_pilot_carriers.size()].size() !=
            d_pilot_symbols[i % d_pilot_symbols.size()].size()) {
            throw std::invalid_argument("pilot_carriers do not match pilot_symbols");
        }
    }
    for (unsigned i = 0; i < d_sync_words.size(); i++) {
        if (d_sync_words[i].size() != (unsigned)d_fft_len) {
            throw std::invalid_argument("sync words must be fft length");
        }
    }

    for (unsigned i = 0; i < d_occupied_carriers.size(); i++) {
        d_symbols_per_set += d_occupied_carriers[i].size();
    }
    set_tag_propagation_policy(TPP_DONT);
    set_relative_rate((uint64_t)d_symbols_per_set, (uint64_t)d_occupied_carriers.size());
}

ofdm_carrier_allocator_cvc_impl::~ofdm_carrier_allocator_cvc_impl() {}

int ofdm_carrier_allocator_cvc_impl::calculate_output_stream_length(
    const gr_vector_int& ninput_items)
{
    int nin = ninput_items[0];
    int nout = (nin / d_symbols_per_set) * d_occupied_carriers.size();
    int k = 0;
    for (int i = 0; i < nin % d_symbols_per_set; k++) {
        nout++;
        i += d_occupied_carriers[k % d_occupied_carriers.size()].size();
    }
    return nout + d_sync_words.size();
}

int ofdm_carrier_allocator_cvc_impl::work(int noutput_items,
                                          gr_vector_int& ninput_items,
                                          gr_vector_const_void_star& input_items,
                                          gr_vector_void_star& output_items)
{
    const gr_complex* in = (const gr_complex*)input_items[0];
    gr_complex* out = (gr_complex*)output_items[0];
    std::vector<tag_t> tags;

    memset((void*)out, 0x00, sizeof(gr_complex) * d_fft_len * noutput_items);
    // Copy Sync word
    for (unsigned i = 0; i < d_sync_words.size(); i++) {
        memcpy((void*)out, (void*)&d_sync_words[i][0], sizeof(gr_complex) * d_fft_len);
        out += d_fft_len;
    }

    // Copy data symbols
    long n_ofdm_symbols = 0; // Number of output items
    int curr_set = 0;
    int symbols_to_allocate = d_occupied_carriers[0].size();
    int symbols_allocated = 0;
    for (int i = 0; i < ninput_items[0]; i++) {
        if (symbols_allocated == 0) {
            // Copy all tags associated with these input symbols onto this OFDM symbol
            get_tags_in_range(
                tags,
                0,
                nitems_read(0) + i,
                nitems_read(0) + std::min(i + symbols_to_allocate, (int)ninput_items[0]));
            for (unsigned t = 0; t < tags.size(); t++) {
                add_item_tag(0,
                             nitems_written(0) + n_ofdm_symbols +
                                 (n_ofdm_symbols == 0 ? 0 : d_sync_words.size()),
                             tags[t].key,
                             tags[t].value);
            }
            n_ofdm_symbols++;
        }
        out[(n_ofdm_symbols - 1) * d_fft_len +
            d_occupied_carriers[curr_set][symbols_allocated]] = in[i];
        symbols_allocated++;
        if (symbols_allocated == symbols_to_allocate) {
            curr_set = (curr_set + 1) % d_occupied_carriers.size();
            symbols_to_allocate = d_occupied_carriers[curr_set].size();
            symbols_allocated = 0;
        }
    }
    // Copy pilot symbols
    for (int i = 0; i < n_ofdm_symbols; i++) {
        for (unsigned k = 0; k < d_pilot_carriers[i % d_pilot_carriers.size()].size();
             k++) {
            out[i * d_fft_len + d_pilot_carriers[i % d_pilot_carriers.size()][k]] =
                d_pilot_symbols[i % d_pilot_symbols.size()][k];
        }
    }

    return n_ofdm_symbols + d_sync_words.size();
}

} // namespace digital
} // namespace gr
