#ifndef BOOST_PYTHON_MAKE_TUPLE_FROM_FUSION_H_
#define BOOST_PYTHON_MAKE_TUPLE_FROM_FUSION_H_


#include <boost/fusion/algorithm/iteration/for_each.hpp>
#include <boost/fusion/include/size.hpp>
#include <boost/fusion/include/is_sequence.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/python/tuple.hpp>


namespace boost {
namespace python {


class tuple_maker
{
public:
    tuple_maker(tuple& t):
    m_tuple(t),
    m_iteration(0)
    {}

    template <class T>
    typename disable_if<fusion::traits::is_sequence<T>, void>::type
    operator() (const T& element) const
    { add_element(element); }

    template <class Sequence>
    typename enable_if<fusion::traits::is_sequence<Sequence>, void>::type
    operator() (const Sequence& s) const
    { add_element(make_tuple_from_fusion(s)); }

private:
    template <class T>
    void add_element(const T& element) const
    {
        PyTuple_SET_ITEM(
            m_tuple.ptr(),
            m_iteration++,
            incref(object(element).ptr())
        );
    }

    tuple& m_tuple;
    mutable int m_iteration;
};


template <class Sequence>
tuple make_tuple_from_fusion(const Sequence& s)
{
    tuple result((detail::new_reference)::PyTuple_New(fusion::size(s)));
    fusion::for_each(s, tuple_maker(result));
    return result;
}


} // namespace python
} // namespace boost


#endif