/* -*- c++ -*- */
/*
 * Copyright 2008,2010,2012 Free Software Foundation, Inc.
 *
 * 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 "cpfsk_bc_impl.h"
#include <gr_io_signature.h>
#include <gr_expj.h>

namespace gr {
  namespace analog {
    
#define M_TWOPI (2*M_PI)

    cpfsk_bc::sptr
    cpfsk_bc::make(float k, float ampl, int samples_per_sym)
    {
      return gnuradio::get_initial_sptr
	(new cpfsk_bc_impl(k, ampl, samples_per_sym));
    }

    cpfsk_bc_impl::cpfsk_bc_impl(float k, float ampl, int samples_per_sym)
      : gr_sync_interpolator("cpfsk_bc",
			     gr_make_io_signature(1, 1, sizeof(char)),
			     gr_make_io_signature(1, 1, sizeof(gr_complex)),
			     samples_per_sym)
    {
      d_samples_per_sym = samples_per_sym;
      d_freq = k*M_PI/samples_per_sym;
      d_ampl = ampl;
      d_phase = 0.0;
    }

    cpfsk_bc_impl::~cpfsk_bc_impl()
    {
    }

    int
    cpfsk_bc_impl::work(int noutput_items,
			gr_vector_const_void_star &input_items,
			gr_vector_void_star &output_items)
    {
      const char *in = (const char*)input_items[0];
      gr_complex *out = (gr_complex*)output_items[0];

      for(int i = 0; i < noutput_items/d_samples_per_sym; i++) {
	for(int j = 0; j < d_samples_per_sym; j++) {
	  if(in[i] == 1)
	    d_phase += d_freq;
	  else
	    d_phase -= d_freq;

	  while(d_phase > M_TWOPI)
	    d_phase -= M_TWOPI;
	  while(d_phase < -M_TWOPI)
	    d_phase += M_TWOPI;

	  *out++ = gr_expj(d_phase)*d_ampl;
	}
      }

      return noutput_items;
    }

  } /* namespace analog */
} /* namespace gr */