//C++ header - Open Scene Graph - Copyright (C) 1998-2002 Robert Osfield
//Distributed under the terms of the GNU Library General Public License (LGPL)
//as published by the Free Software Foundation.
//osgParticle - Copyright (C) 2002 Marco Jez

#ifndef OSGPARTICLE_PARTICLESYSTEMUPDATER_
#define OSGPARTICLE_PARTICLESYSTEMUPDATER_ 1

#include <osgParticle/Export>
#include <osgParticle/ParticleSystem>

#include <vector>

#include <osg/ref_ptr>
#include <osg/CopyOp>
#include <osg/Object>
#include <osg/Node>
#include <osg/NodeVisitor>

#include <osgUtil/CullVisitor>

namespace osgParticle
{

    /**    A useful node class for updating particle systems automatically.
        When a <CODE>ParticleSystemUpdater</CODE> is traversed by a cull visitor, it calls the
        <CODE>update()</CODE> method on the specified particle systems. You should place this updater
        <U>AFTER</U> other nodes like emitters and programs.
    */
    class OSGPARTICLE_EXPORT ParticleSystemUpdater: public osg::Node {
    public:
        ParticleSystemUpdater();
        ParticleSystemUpdater(const ParticleSystemUpdater &copy, const osg::CopyOp &copyop = osg::CopyOp::SHALLOW_COPY);
        
        META_Node(osgParticle,ParticleSystemUpdater);
        
        /// Return the number of particle systems on the list.
        inline int numParticleSystems() const;
        
        /// Add a particle system to the list.
        inline void addParticleSystem(ParticleSystem *ps);
        
        /// Get a const particle system from the list.
        inline const ParticleSystem *getParticleSystem(int i) const;
        
        /// Get a particle system from the list.
        inline ParticleSystem *getParticleSystem(int i);
        
        /// Find a particle system.
        inline int findParticleSystem(ParticleSystem *ps) const;
        
        /// Remove a particle system from the list (by index).
        inline void removeParticleSystem(int i);
        
        /// Remove a particle system from the list (by pointer).
        inline bool removeParticleSystem(ParticleSystem *ps);
        
        virtual void traverse(osg::NodeVisitor &nv);
        
    protected:
        virtual ~ParticleSystemUpdater() {}
        ParticleSystemUpdater &operator=(const ParticleSystemUpdater &) { return *this; }
        
        inline virtual const bool computeBound() const;        
        
    private:
        typedef std::vector<osg::ref_ptr<ParticleSystem> > ParticleSystem_Vector;
        
        ParticleSystem_Vector psv_;
        double t0_;
    };
    
    // INLINE FUNCTIONS
    
    inline const bool ParticleSystemUpdater::computeBound() const
    {
        _bsphere.init();
        _bsphere_computed = true;
        return true;
    }

    inline int ParticleSystemUpdater::numParticleSystems() const
    {
        return static_cast<int>(psv_.size());
    }
    
    inline void ParticleSystemUpdater::addParticleSystem(ParticleSystem *ps)
    {
        psv_.push_back(ps);
    }
    
    inline const ParticleSystem *ParticleSystemUpdater::getParticleSystem(int i) const
    {
        return psv_[i].get();
    }
    
    inline ParticleSystem *ParticleSystemUpdater::getParticleSystem(int i)
    {
        return psv_[i].get();
    }
    
    inline void ParticleSystemUpdater::removeParticleSystem(int i)
    {
        psv_.erase(psv_.begin()+i);
    }
    
    inline int ParticleSystemUpdater::findParticleSystem(ParticleSystem *ps) const
    {
        ParticleSystem_Vector::const_iterator i;
        int j = 0;
        for (i=psv_.begin(); i!=psv_.end(); ++i, ++j) {
            if (i->get() == ps) return j;
        }
        return -1;
    }
    
    inline bool ParticleSystemUpdater::removeParticleSystem(ParticleSystem *ps)
    {
        int i = findParticleSystem(ps);
        if (i == -1) return false;
        removeParticleSystem(i);
        return true;
    }
    

}

#endif