/*
 * Copyright (c) 2005 by the Windstille team. All rights reserved.
 *
 * collision_engine.hxx
 * by David Kamphausen (david.kamphausen@web.de)
 *    Ingo Ruhnke
 *
 * The "Windstille" project, including all files needed to compile it,
 * is free software; you can redistribute it and/or use 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.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program.
 */

#ifndef HEADER_COLLISION_ENGINE_HPP
#define HEADER_COLLISION_ENGINE_HPP

#include "collision_object.hpp"

class DrawingContext;

class CollisionEngine
{
private:
  typedef std::vector<CollisionObject*> Objects;
  Objects objects;
  float unstuck_velocity;

public:
  CollisionEngine();
  ~CollisionEngine();

  void draw(DrawingContext& dc);
  void update(float delta);
  void update(CollisionObject& obj, float delta);
  void collision(const CollisionData &result);

  CollisionObject* add(CollisionObject *obj);
  void remove(CollisionObject *obj);

  /** Shoots a ray from \a pos into direction \a angle, returns the
      position were the ray collides with the tilemap FIXME: Should be
      extended to handle objects as well */
  Vector raycast(const Vector& pos, float angle);
private:
  void unstuck(CollisionObject& a, CollisionObject& b, float delta);
  CollisionData collide(CollisionObject& a, CollisionObject& b, float delta);
  CollisionData collide(const Rectf& b1, const Rectf& b2,
                        const Vector& b1_v, const Vector& b2_v,
                        float delta);
  CollisionData collide_tilemap(CollisionObject& a, CollisionObject& b, float delta);

  void unstuck_tilemap(CollisionObject& a, CollisionObject& b, float delta);
  void unstuck_rect_rect(CollisionObject& a, CollisionObject& b, float delta);
};

#endif