/* -*- c++ -*- */
/* 
 * Copyright 2019 Thomas Kolb.
 * 
 * This 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.
 * 
 * This software 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 this software; 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/io_signature.h>
#include "symbol_interleaver_impl.h"

namespace gr {
	namespace hamnet70 {

		symbol_interleaver::sptr
		symbol_interleaver::make(size_t interleaver_width, bool deinterleave, const std::string &length_tag)
		{
			return gnuradio::get_initial_sptr
				(new symbol_interleaver_impl(interleaver_width, deinterleave, length_tag));
		}

		/*
		 * The private constructor
		 */
		symbol_interleaver_impl::symbol_interleaver_impl(size_t interleaver_width, bool deinterleave, const std::string &length_tag)
			: gr::tagged_stream_block("symbol_interleaver",
					gr::io_signature::make(1, 1, sizeof(gr_complex)),
					gr::io_signature::make(1, 1, sizeof(gr_complex)), length_tag),
				d_width(interleaver_width),
				d_deinterleave(deinterleave)
		{}

		/*
		 * Our virtual destructor.
		 */
		symbol_interleaver_impl::~symbol_interleaver_impl()
		{
		}

		int
		symbol_interleaver_impl::calculate_output_stream_length(const gr_vector_int &ninput_items)
		{
			int noutput_items = ninput_items[0];
			return noutput_items ;
		}

		int
		symbol_interleaver_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];

			size_t nitems = ninput_items[0];

			size_t ncols = d_width;
			size_t nfullcols = nitems % d_width;

			size_t nrows = nitems / d_width;
			if(nitems % nrows != 0) {
				nrows++;
			}

			size_t row = 0;
			size_t col = 0;

			for(size_t i = 0; i < nitems; i++) {
				size_t swapped_i = ncols * row + col;

				row++;
				if ((col >= nfullcols && row == (nrows-1))
						|| row == nrows) {
					col++;
					row = 0;
				}

				if(d_deinterleave) {
					out[i] = in[swapped_i];
				} else { /* interleave */
					out[swapped_i] = in[i];
				}
			}

			noutput_items = nitems;

			// Tell runtime system how many output items we produced.
			return noutput_items;
		}

	} /* namespace hamnet70 */
} /* namespace gr */