/*

Copyright (C) 2008 Michael Goffioul

This file is part of Octave.

Octave 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 of the License, or (at your
option) any later version.

Octave 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 Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#if !defined (graphics_backend_h)
#define graphics_backend_h 1

#include "dMatrix.h"
#include "graphics.h"

class graphics_backend;

class base_graphics_backend
{
public:
  friend class graphics_backend;

public:
  base_graphics_backend (const std::string& nm)
      : name (nm), count (0) { }

  virtual ~base_graphics_backend (void) { }

  std::string get_name (void) const { return name; }

  virtual void close_figure (const figure::properties&) const
    { error ("close_figure: invalid graphics backend"); }

  virtual Matrix get_canvas_size (const graphics_handle&) const
    {
      error ("get_canvas_size: invalid graphics backend");
      return Matrix (1, 2, 0.0);
    }

  virtual Matrix get_figure_position (const graphics_handle&) const
    {
      error ("get_figure_position: invalid graphics backend");
      return Matrix (1, 4, 0.0);
    }

private:
  std::string name;
  int count;
};

class graphics_backend
{
public:
  graphics_backend (void)
      : rep (new base_graphics_backend ("unknown"))
    {
      rep->count++;
    }

  graphics_backend (base_graphics_backend* b)
      : rep (b)
    {
      rep->count++;
    }

  graphics_backend (const graphics_backend& b)
      : rep (b.rep)
    {
      rep->count++;
    }

  ~graphics_backend (void)
    {
      if (--rep->count == 0)
	delete rep;
    }

  graphics_backend& operator = (const graphics_backend& b)
    {
      if (rep != b.rep)
	{
	  if (--rep->count == 0)
	    delete rep;

	  rep = b.rep;
	  rep->count++;
	}

      return *this;
    }

  std::string get_name (void) const { return rep->get_name (); }

  void close_figure (const figure::properties& props) const
    { rep->close_figure (props); }

  Matrix get_canvas_size (const graphics_handle& fh) const
    { return rep->get_canvas_size (fh); }

  Matrix get_figure_position (const graphics_handle& fh) const
    { return rep->get_figure_position (fh); }

  OCTINTERP_API static graphics_backend default_backend (void);

  static void register_backend (const graphics_backend& b)
    { available_backends[b.get_name ()] = b; }

  static void unregister_backend (const std::string& name)
    { available_backends.erase (name); }

private:
  base_graphics_backend *rep;

private:
  static std::map<std::string, graphics_backend> available_backends;
};

#endif

/*
;;; Local Variables: ***
;;; mode: C++ ***
;;; End: ***
*/