//============================================================================
//  Copyright (c) Kitware, Inc.
//  All rights reserved.
//  See LICENSE.txt for details.
//
//  This software is distributed WITHOUT ANY WARRANTY; without even
//  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
//  PURPOSE.  See the above copyright notice for more information.
//============================================================================

#ifndef vtk_m_filter_FilterTraits_h
#define vtk_m_filter_FilterTraits_h

#include <vtkm/TypeListTag.h>

namespace vtkm
{
namespace filter
{

template <typename Derived>
class Filter;

namespace detail
{
// template<typename T> vtkm::ListTagBase<T> as_list(T);
vtkm::ListTagUniversal as_list(vtkm::ListTagUniversal);
template <typename... T>
vtkm::ListTagBase<T...> as_list(vtkm::ListTagBase<T...>);
}


template <typename Filter>
struct FilterTraits
{
  using InputFieldTypeList =
    decltype(detail::as_list(std::declval<typename Filter::SupportedTypes>()));
  using AdditionalFieldStorage = typename Filter::AdditionalFieldStorage;
};

template <typename DerivedPolicy, typename ListOfTypes>
struct DeduceFilterFieldTypes
{
  using PList = typename DerivedPolicy::FieldTypeList;
  using TypeList = vtkm::ListTagIntersect<ListOfTypes, PList>;
};
}
}

#endif //vtk_m_filter_FilterTraits_h
