#include <boost/test/auto_unit_test.hpp>
#include <boost/mpl/int.hpp>
#include <boost/mpl/vector_c.hpp>
#include <boost/mpl/equal.hpp>
#include <boost/mpl/size.hpp>
#include <boost/mpl/at.hpp>

#include <vector>

typedef std::vector<int> int_vector;

namespace
{
    template<class Func, class Begin, class End>
    typename Func::return_type to_compile_time(int i, boost::mpl::true_)
    {
        if (i == Begin::value)
            return Func::apply<Begin>(i);
        else
            return to_compile_time<Func, Begin::next, End>(i);
    }

    template<class Func, class Begin, class End>
    typename Func::return_type to_compile_time(int, boost::mpl::false_)
    {
        return Func::return_type();
    }

    template<class Func, class Begin, class End>
    typename Func::return_type to_compile_time(int i)
    {
        return to_compile_time<Func, Begin, End>(i, boost::mpl::less<Begin, End>());
    }
}


template<class GradeList>
struct get_at
{
    typedef int return_type;
    
    template<class I>
    static return_type apply(int)
    {
        return boost::mpl::at<GradeList, I>::type::value;
    }
};


template<class GradeList>
int_vector to_runtime()
{
    const int size = boost::mpl::size<GradeList>::type::value;
    int_vector ret;
    ret.reserve(size);
    for (int i = 0; i < size; ++i)
    {
        ret.push_back(
            to_compile_time
            <
                get_at<GradeList>, 
                boost::mpl::int_<0>, 
                typename boost::mpl::size<GradeList>::type
            >(i));
    }
    return ret;
}

BOOST_AUTO_UNIT_TEST(test_compile_time_int_vector_to_runtime_int_vector)
{
    typedef boost::mpl::vector_c<int, 0, 1, 5, 6, 2, 5> c_list;
    
    int_vector r_list = to_runtime<c_list>();

    BOOST_CHECK((boost::mpl::size<c_list>::type::value == r_list.size()));
    BOOST_CHECK((boost::mpl::at_c<c_list, 0>::type::value == r_list[0]));
    BOOST_CHECK((boost::mpl::at_c<c_list, 1>::type::value == r_list[1]));
    BOOST_CHECK((boost::mpl::at_c<c_list, 2>::type::value == r_list[2]));
    BOOST_CHECK((boost::mpl::at_c<c_list, 3>::type::value == r_list[3]));
    BOOST_CHECK((boost::mpl::at_c<c_list, 4>::type::value == r_list[4]));
    BOOST_CHECK((boost::mpl::at_c<c_list, 5>::type::value == r_list[5]));
}