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

/*

 * Copyright 2005 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.

 */

#ifndef _GR_VCO_H_

#define _GR_VCO_H_

#include <vector>

#include <gr_sincos.h>

#include <cmath>

#include <gr_complex.h>

/*!

 * \brief base class template for Voltage Controlled Oscillator (VCO)

 * \ingroup misc

 */

//FIXME  Eventually generalize this to fixed point

template<class o_type, class i_type>

class gr_vco {

public:

  gr_vco () : d_phase (0) {}

  virtual ~gr_vco () {}

  // radians

  void set_phase (double angle) {

    d_phase = angle;

  }

  void adjust_phase (double delta_phase) {

    d_phase += delta_phase;

    if (fabs (d_phase) > M_PI){

      while (d_phase > M_PI)

        d_phase -= 2*M_PI;

      while (d_phase < -M_PI)

        d_phase += 2*M_PI;

    }

  }

  double get_phase () const { return d_phase; }

  // compute sin and cos for current phase angle

  void sincos (float *sinx, float *cosx) const;

  // compute cos or sin for current phase angle

  float cos () const { return std::cos (d_phase); }

  float sin () const { return std::sin (d_phase); }

  // compute a block at a time

  void cos (float *output, const float *input, int noutput_items, double k, double ampl = 1.0);

protected:

  double d_phase;

};

template<class o_type, class i_type>

void

gr_vco<o_type,i_type>::sincos (float *sinx, float *cosx) const

{

  gr_sincosf (d_phase, sinx, cosx);

}

template<class o_type, class i_type>

void

gr_vco<o_type,i_type>::cos (float *output, const float *input, int noutput_items, double k, double ampl)

{

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

    output[i] = cos() * ampl;

    adjust_phase(input[i] * k);

  }

}

#endif /* _GR_VCO_H_ */