/*  $Id$
**   __      __ __             ___        __   __ __   __
**  /  \    /  \__| ____    __| _/_______/  |_|__|  | |  |   ____
**  \   \/\/   /  |/    \  / __ |/  ___/\   __\  |  | |  | _/ __ \
**   \        /|  |   |  \/ /_/ |\___ \  |  | |  |  |_|  |_\  ___/
**    \__/\  / |__|___|  /\____ /____  > |__| |__|____/____/\___  >
**         \/          \/      \/    \/                         \/
**  Copyright (C) 2005 Ingo Ruhnke <grumbel@gmx.de>
**
**  This program 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 2
**  of the License, or (at your option) any later version.
**
**  This program 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 program; if not, write to the Free Software
**  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
**  02111-1307, USA.
*/

#ifndef HEADER_STAIR_CONTACT_HPP
#define HEADER_STAIR_CONTACT_HPP

#include "contact.hpp"

class TileMap;

/** A special contact to walk stairs up or down */
class StairContact : public Contact
{
private:
  /** The tilemap with which the contact interacts */
  TileMap* tilemap;

  /** Current position in unit of tiles */
  Point pos;

  /** Amount of how much we are away from the center of the tile, its
      in range [-0.5, 0.5], else we move on to the next tile.
      advancement is in sync with the x-axis, y-axis depend on
      direction */
  float advancement;

  unsigned int tile_type;

public:
  StairContact(TileMap* tilemap, const Point& p);
  
  void update(float delta);

  /** Move the contact forward or backward across the stairs */
  void advance(float s);

  /** Get the current position in world coordinates */
  Vector get_pos() const;

  /** Return false when the given contact has left the stairs */
  bool is_active() const;

private:
  void advance_or_not();

  StairContact (const StairContact&);
  StairContact& operator= (const StairContact&);
};

#endif

/* EOF */