#ifndef OSGUTIL_OPERATIONARRAYFUNCTOR
#define OSGUTIL_OPERATIONARRAYFUNCTOR 1


#include <osg/Array>
#include <osgUtil/ConvertVec>

// ** template ArrayVisitor to handle all method in one template.
// **  Only use when process done on each array could be templated

namespace osgUtil {

template <class T>
class OperationArrayFunctor : public osg::ArrayVisitor, public T
{
    public:
        
        virtual void apply(osg::Array&) {}
//        virtual void apply(osg::ByteArray& array) { T::process<osg::ByteArray>(array); }
//        virtual void apply(osg::ShortArray& array) { T::process(array); }
//        virtual void apply(osg::IntArray& array) { T::process<osg::IntArray>(array); }
//        virtual void apply(osg::UByteArray& array) { T::process<osg::UByteArray>(array); }
//        virtual void apply(osg::UShortArray& array) { T::process<osg::UShortArray>(array); }
//        virtual void apply(osg::UIntArray& array) { T::process<osg::UIntArray>(array); }
//        virtual void apply(osg::FloatArray& array) { T::process<osg::FloatArray>(array); }
//        virtual void apply(osg::DoubleArray& array) { T::process<osg::DoubleArray>(array); }

        virtual void apply(osg::Vec2Array & array) { T::process(array); }
        virtual void apply(osg::Vec3Array& array) { T::process(array); }
        virtual void apply(osg::Vec4Array& array) { T::process(array); }

        virtual void apply(osg::Vec4ubArray& array) { T::process(array); }

        virtual void apply(osg::Vec2bArray& array) { T::process(array); }
        virtual void apply(osg::Vec3bArray& array) { T::process(array); }
        virtual void apply(osg::Vec4bArray& array) { T::process(array); }

        virtual void apply(osg::Vec2sArray& array) { T::process(array); }
        virtual void apply(osg::Vec3sArray& array) { T::process(array); }
        virtual void apply(osg::Vec4sArray& array) { T::process(array); }

        virtual void apply(osg::Vec2dArray& array) { T::process(array); }
        virtual void apply(osg::Vec3dArray& array) { T::process(array); }
        virtual void apply(osg::Vec4dArray& array) { T::process(array); }
};

struct AddRangeOperator
{
    template <typename ArrayType>
    void process(ArrayType & array) 
    {   
        typedef typename ArrayType::ElementDataType ElementDataType;
                
        ElementDataType convertedVector;
        osgUtil::ConvertVec<osg::Vec3, ElementDataType>::convert(_vector, convertedVector);
        
        typename ArrayType::iterator it = array.begin();
        std::advance(it, _begin);
        
        typename ArrayType::iterator end = it;
        std::advance(end, _count);
        
        for (; it < end; ++it)
            (*it) += convertedVector;
    }

    unsigned int _begin;
    unsigned int _count;
    
    osg::Vec3 _vector;
};
typedef OperationArrayFunctor<AddRangeOperator> AddRangeFunctor;

struct MultiplyRangeOperator
{
    template <typename ArrayType>
    void process(ArrayType & array) 
    {   
        typedef typename ArrayType::ElementDataType ElementDataType;
                
        ElementDataType convertedVector;
        osgUtil::ConvertVec<osg::Vec3, ElementDataType>::convert(_vector, convertedVector);
        
        typename ArrayType::iterator it = array.begin();
        std::advance(it, _begin);
        
        typename ArrayType::iterator end = it;
        std::advance(end, _count);
        
        for (; it < end; ++it)
            (*it) *= convertedVector;
    }

    unsigned int _begin;
    unsigned int _count;
    
    osg::Vec3 _vector;
};
typedef OperationArrayFunctor<MultiplyRangeOperator> MultiplyRangeFunctor;

} // end osgUtil namespace

#endif // ** OPERATIONARRAYFUNCTOR ** //