/*
 *  Copyright 2008-2013 NVIDIA Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

#pragma once

#include <thrust/detail/config.h>
#include <thrust/detail/static_assert.h>
#include <thrust/system/detail/generic/set_operations.h>
#include <thrust/functional.h>
#include <thrust/detail/internal_functional.h>
#include <thrust/iterator/iterator_traits.h>
#include <thrust/iterator/constant_iterator.h>
#include <thrust/iterator/zip_iterator.h>

THRUST_NAMESPACE_BEGIN
namespace system
{
namespace detail
{
namespace generic
{


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename OutputIterator>
THRUST_HOST_DEVICE
OutputIterator set_difference(thrust::execution_policy<DerivedPolicy> &exec,
                              InputIterator1                           first1,
                              InputIterator1                           last1,
                              InputIterator2                           first2,
                              InputIterator2                           last2,
                              OutputIterator                           result)
{
  using value_type = typename thrust::iterator_value<InputIterator1>::type;
  return thrust::set_difference(exec, first1, last1, first2, last2, result, thrust::less<value_type>());
} // end set_difference()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename InputIterator3,
         typename InputIterator4,
         typename OutputIterator1,
         typename OutputIterator2>
THRUST_HOST_DEVICE
thrust::pair<OutputIterator1,OutputIterator2>
  set_difference_by_key(thrust::execution_policy<DerivedPolicy> &exec,
                        InputIterator1                           keys_first1,
                        InputIterator1                           keys_last1,
                        InputIterator2                           keys_first2,
                        InputIterator2                           keys_last2,
                        InputIterator3                           values_first1,
                        InputIterator4                           values_first2,
                        OutputIterator1                          keys_result,
                        OutputIterator2                          values_result)
{
  using value_type = typename thrust::iterator_value<InputIterator1>::type;
  return thrust::set_difference_by_key(exec, keys_first1, keys_last1, keys_first2, keys_last2, values_first1, values_first2, keys_result, values_result, thrust::less<value_type>());
} // end set_difference_by_key()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename InputIterator3,
         typename InputIterator4,
         typename OutputIterator1,
         typename OutputIterator2,
         typename StrictWeakOrdering>
THRUST_HOST_DEVICE
thrust::pair<OutputIterator1,OutputIterator2>
  set_difference_by_key(thrust::execution_policy<DerivedPolicy> &exec,
                        InputIterator1                           keys_first1,
                        InputIterator1                           keys_last1,
                        InputIterator2                           keys_first2,
                        InputIterator2                           keys_last2,
                        InputIterator3                           values_first1,
                        InputIterator4                           values_first2,
                        OutputIterator1                          keys_result,
                        OutputIterator2                          values_result,
                        StrictWeakOrdering                       comp)
{
  using iterator_tuple1 = thrust::tuple<InputIterator1, InputIterator3>;
  using iterator_tuple2 = thrust::tuple<InputIterator2, InputIterator4>;
  using iterator_tuple3 = thrust::tuple<OutputIterator1, OutputIterator2>;

  using zip_iterator1 = thrust::zip_iterator<iterator_tuple1>;
  using zip_iterator2 = thrust::zip_iterator<iterator_tuple2>;
  using zip_iterator3 = thrust::zip_iterator<iterator_tuple3>;

  zip_iterator1 zipped_first1 = thrust::make_zip_iterator(thrust::make_tuple(keys_first1, values_first1));
  zip_iterator1 zipped_last1  = thrust::make_zip_iterator(thrust::make_tuple(keys_last1, values_first1));

  zip_iterator2 zipped_first2 = thrust::make_zip_iterator(thrust::make_tuple(keys_first2, values_first2));
  zip_iterator2 zipped_last2  = thrust::make_zip_iterator(thrust::make_tuple(keys_last2, values_first2));

  zip_iterator3 zipped_result = thrust::make_zip_iterator(thrust::make_tuple(keys_result, values_result));

  thrust::detail::compare_first<StrictWeakOrdering> comp_first(comp);

  iterator_tuple3 result = thrust::set_difference(exec, zipped_first1, zipped_last1, zipped_first2, zipped_last2, zipped_result, comp_first).get_iterator_tuple();

  return thrust::make_pair(thrust::get<0>(result), thrust::get<1>(result));
} // end set_difference_by_key()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename OutputIterator>
THRUST_HOST_DEVICE
OutputIterator set_intersection(thrust::execution_policy<DerivedPolicy> &exec,
                                InputIterator1                           first1,
                                InputIterator1                           last1,
                                InputIterator2                           first2,
                                InputIterator2                           last2,
                                OutputIterator                           result)
{
  using value_type = typename thrust::iterator_value<InputIterator1>::type;
  return thrust::set_intersection(exec, first1, last1, first2, last2, result, thrust::less<value_type>());
} // end set_intersection()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename InputIterator3,
         typename OutputIterator1,
         typename OutputIterator2>
THRUST_HOST_DEVICE
thrust::pair<OutputIterator1,OutputIterator2>
  set_intersection_by_key(thrust::execution_policy<DerivedPolicy> &exec,
                          InputIterator1                           keys_first1,
                          InputIterator1                           keys_last1,
                          InputIterator2                           keys_first2,
                          InputIterator2                           keys_last2,
                          InputIterator3                           values_first1,
                          OutputIterator1                          keys_result,
                          OutputIterator2                          values_result)
{
  using value_type = typename thrust::iterator_value<InputIterator1>::type;
  return thrust::set_intersection_by_key(exec, keys_first1, keys_last1, keys_first2, keys_last2, values_first1, keys_result, values_result, thrust::less<value_type>());
} // end set_intersection_by_key()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename InputIterator3,
         typename OutputIterator1,
         typename OutputIterator2,
         typename StrictWeakOrdering>
THRUST_HOST_DEVICE
thrust::pair<OutputIterator1,OutputIterator2>
  set_intersection_by_key(thrust::execution_policy<DerivedPolicy> &exec,
                          InputIterator1                           keys_first1,
                          InputIterator1                           keys_last1,
                          InputIterator2                           keys_first2,
                          InputIterator2                           keys_last2,
                          InputIterator3                           values_first1,
                          OutputIterator1                          keys_result,
                          OutputIterator2                          values_result,
                          StrictWeakOrdering                       comp)
{
  using value_type1       = typename thrust::iterator_value<InputIterator3>::type;
  using constant_iterator = thrust::constant_iterator<value_type1>;

  using iterator_tuple1 = thrust::tuple<InputIterator1, InputIterator3>;
  using iterator_tuple2 = thrust::tuple<InputIterator2, constant_iterator>;
  using iterator_tuple3 = thrust::tuple<OutputIterator1, OutputIterator2>;

  using zip_iterator1 = thrust::zip_iterator<iterator_tuple1>;
  using zip_iterator2 = thrust::zip_iterator<iterator_tuple2>;
  using zip_iterator3 = thrust::zip_iterator<iterator_tuple3>;

  // fabricate a values_first2 by repeating a default-constructed value_type1
  // XXX assumes value_type1 is default-constructible
  constant_iterator values_first2 = thrust::make_constant_iterator(value_type1());

  zip_iterator1 zipped_first1 = thrust::make_zip_iterator(thrust::make_tuple(keys_first1, values_first1));
  zip_iterator1 zipped_last1  = thrust::make_zip_iterator(thrust::make_tuple(keys_last1, values_first1));

  zip_iterator2 zipped_first2 = thrust::make_zip_iterator(thrust::make_tuple(keys_first2, values_first2));
  zip_iterator2 zipped_last2  = thrust::make_zip_iterator(thrust::make_tuple(keys_last2, values_first2));

  zip_iterator3 zipped_result = thrust::make_zip_iterator(thrust::make_tuple(keys_result, values_result));

  thrust::detail::compare_first<StrictWeakOrdering> comp_first(comp);

  iterator_tuple3 result = thrust::set_intersection(exec, zipped_first1, zipped_last1, zipped_first2, zipped_last2, zipped_result, comp_first).get_iterator_tuple();

  return thrust::make_pair(thrust::get<0>(result), thrust::get<1>(result));
} // end set_intersection_by_key()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename OutputIterator>
THRUST_HOST_DEVICE
OutputIterator set_symmetric_difference(thrust::execution_policy<DerivedPolicy> &exec,
                                        InputIterator1                           first1,
                                        InputIterator1                           last1,
                                        InputIterator2                           first2,
                                        InputIterator2                           last2,
                                        OutputIterator                           result)
{
  using value_type = typename thrust::iterator_value<InputIterator1>::type;
  return thrust::set_symmetric_difference(exec, first1, last1, first2, last2, result, thrust::less<value_type>());
} // end set_symmetric_difference()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename InputIterator3,
         typename InputIterator4,
         typename OutputIterator1,
         typename OutputIterator2>
THRUST_HOST_DEVICE
thrust::pair<OutputIterator1,OutputIterator2>
  set_symmetric_difference_by_key(thrust::execution_policy<DerivedPolicy> &exec,
                                  InputIterator1                           keys_first1,
                                  InputIterator1                           keys_last1,
                                  InputIterator2                           keys_first2,
                                  InputIterator2                           keys_last2,
                                  InputIterator3                           values_first1,
                                  InputIterator4                           values_first2,
                                  OutputIterator1                          keys_result,
                                  OutputIterator2                          values_result)
{
  using value_type = typename thrust::iterator_value<InputIterator1>::type;
  return thrust::set_symmetric_difference_by_key(exec, keys_first1, keys_last1, keys_first2, keys_last2, values_first1, values_first2, keys_result, values_result, thrust::less<value_type>());
} // end set_symmetric_difference_by_key()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename InputIterator3,
         typename InputIterator4,
         typename OutputIterator1,
         typename OutputIterator2,
         typename StrictWeakOrdering>
THRUST_HOST_DEVICE
thrust::pair<OutputIterator1,OutputIterator2>
  set_symmetric_difference_by_key(thrust::execution_policy<DerivedPolicy> &exec,
                                  InputIterator1                           keys_first1,
                                  InputIterator1                           keys_last1,
                                  InputIterator2                           keys_first2,
                                  InputIterator2                           keys_last2,
                                  InputIterator3                           values_first1,
                                  InputIterator4                           values_first2,
                                  OutputIterator1                          keys_result,
                                  OutputIterator2                          values_result,
                                  StrictWeakOrdering                       comp)
{
  using iterator_tuple1 = thrust::tuple<InputIterator1, InputIterator3>;
  using iterator_tuple2 = thrust::tuple<InputIterator2, InputIterator4>;
  using iterator_tuple3 = thrust::tuple<OutputIterator1, OutputIterator2>;

  using zip_iterator1 = thrust::zip_iterator<iterator_tuple1>;
  using zip_iterator2 = thrust::zip_iterator<iterator_tuple2>;
  using zip_iterator3 = thrust::zip_iterator<iterator_tuple3>;

  zip_iterator1 zipped_first1 = thrust::make_zip_iterator(thrust::make_tuple(keys_first1, values_first1));
  zip_iterator1 zipped_last1  = thrust::make_zip_iterator(thrust::make_tuple(keys_last1, values_first1));

  zip_iterator2 zipped_first2 = thrust::make_zip_iterator(thrust::make_tuple(keys_first2, values_first2));
  zip_iterator2 zipped_last2  = thrust::make_zip_iterator(thrust::make_tuple(keys_last2, values_first2));

  zip_iterator3 zipped_result = thrust::make_zip_iterator(thrust::make_tuple(keys_result, values_result));

  thrust::detail::compare_first<StrictWeakOrdering> comp_first(comp);

  iterator_tuple3 result = thrust::set_symmetric_difference(exec, zipped_first1, zipped_last1, zipped_first2, zipped_last2, zipped_result, comp_first).get_iterator_tuple();

  return thrust::make_pair(thrust::get<0>(result), thrust::get<1>(result));
} // end set_symmetric_difference_by_key()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename OutputIterator>
THRUST_HOST_DEVICE
OutputIterator set_union(thrust::execution_policy<DerivedPolicy> &exec,
                         InputIterator1                           first1,
                         InputIterator1                           last1,
                         InputIterator2                           first2,
                         InputIterator2                           last2,
                         OutputIterator                           result)
{
  using value_type = typename thrust::iterator_value<InputIterator1>::type;
  return thrust::set_union(exec, first1, last1, first2, last2, result, thrust::less<value_type>());
} // end set_union()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename InputIterator3,
         typename InputIterator4,
         typename OutputIterator1,
         typename OutputIterator2>
THRUST_HOST_DEVICE
thrust::pair<OutputIterator1,OutputIterator2>
  set_union_by_key(thrust::execution_policy<DerivedPolicy> &exec,
                   InputIterator1                           keys_first1,
                   InputIterator1                           keys_last1,
                   InputIterator2                           keys_first2,
                   InputIterator2                           keys_last2,
                   InputIterator3                           values_first1,
                   InputIterator4                           values_first2,
                   OutputIterator1                          keys_result,
                   OutputIterator2                          values_result)
{
  using value_type = typename thrust::iterator_value<InputIterator1>::type;
  return thrust::set_union_by_key(exec, keys_first1, keys_last1, keys_first2, keys_last2, values_first1, values_first2, keys_result, values_result, thrust::less<value_type>());
} // end set_union_by_key()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename InputIterator3,
         typename InputIterator4,
         typename OutputIterator1,
         typename OutputIterator2,
         typename StrictWeakOrdering>
THRUST_HOST_DEVICE
thrust::pair<OutputIterator1,OutputIterator2>
  set_union_by_key(thrust::execution_policy<DerivedPolicy> &exec,
                   InputIterator1                           keys_first1,
                   InputIterator1                           keys_last1,
                   InputIterator2                           keys_first2,
                   InputIterator2                           keys_last2,
                   InputIterator3                           values_first1,
                   InputIterator4                           values_first2,
                   OutputIterator1                          keys_result,
                   OutputIterator2                          values_result,
                   StrictWeakOrdering                       comp)
{
  using iterator_tuple1 = thrust::tuple<InputIterator1, InputIterator3>;
  using iterator_tuple2 = thrust::tuple<InputIterator2, InputIterator4>;
  using iterator_tuple3 = thrust::tuple<OutputIterator1, OutputIterator2>;

  using zip_iterator1 = thrust::zip_iterator<iterator_tuple1>;
  using zip_iterator2 = thrust::zip_iterator<iterator_tuple2>;
  using zip_iterator3 = thrust::zip_iterator<iterator_tuple3>;

  zip_iterator1 zipped_first1 = thrust::make_zip_iterator(thrust::make_tuple(keys_first1, values_first1));
  zip_iterator1 zipped_last1  = thrust::make_zip_iterator(thrust::make_tuple(keys_last1, values_first1));

  zip_iterator2 zipped_first2 = thrust::make_zip_iterator(thrust::make_tuple(keys_first2, values_first2));
  zip_iterator2 zipped_last2  = thrust::make_zip_iterator(thrust::make_tuple(keys_last2, values_first2));

  zip_iterator3 zipped_result = thrust::make_zip_iterator(thrust::make_tuple(keys_result, values_result));

  thrust::detail::compare_first<StrictWeakOrdering> comp_first(comp);

  iterator_tuple3 result = thrust::set_union(exec, zipped_first1, zipped_last1, zipped_first2, zipped_last2, zipped_result, comp_first).get_iterator_tuple();

  return thrust::make_pair(thrust::get<0>(result), thrust::get<1>(result));
} // end set_union_by_key()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename OutputIterator,
         typename StrictWeakOrdering>
THRUST_HOST_DEVICE
OutputIterator set_difference(thrust::execution_policy<DerivedPolicy> &,
                              InputIterator1,
                              InputIterator1,
                              InputIterator2,
                              InputIterator2,
                              OutputIterator  result,
                              StrictWeakOrdering)
{
  THRUST_STATIC_ASSERT_MSG(
    (thrust::detail::depend_on_instantiation<InputIterator1, false>::value)
  , "unimplemented for this system"
  );
  return result;
} // end set_difference()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename OutputIterator,
         typename StrictWeakOrdering>
THRUST_HOST_DEVICE
OutputIterator set_intersection(thrust::execution_policy<DerivedPolicy> &,
                                InputIterator1,
                                InputIterator1,
                                InputIterator2,
                                InputIterator2,
                                OutputIterator result,
                                StrictWeakOrdering)
{
  THRUST_STATIC_ASSERT_MSG(
    (thrust::detail::depend_on_instantiation<InputIterator1, false>::value)
  , "unimplemented for this system"
  );
  return result;
} // end set_intersection()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename OutputIterator,
         typename StrictWeakOrdering>
THRUST_HOST_DEVICE
OutputIterator set_symmetric_difference(thrust::execution_policy<DerivedPolicy> &,
                                        InputIterator1,
                                        InputIterator1,
                                        InputIterator2,
                                        InputIterator2,
                                        OutputIterator result,
                                        StrictWeakOrdering)
{
  THRUST_STATIC_ASSERT_MSG(
    (thrust::detail::depend_on_instantiation<InputIterator1, false>::value)
  , "unimplemented for this system"
  );
  return result;
} // end set_symmetric_difference()


template<typename DerivedPolicy,
         typename InputIterator1,
         typename InputIterator2,
         typename OutputIterator,
         typename StrictWeakOrdering>
THRUST_HOST_DEVICE
OutputIterator set_union(thrust::execution_policy<DerivedPolicy> &,
                         InputIterator1,
                         InputIterator1,
                         InputIterator2,
                         InputIterator2,
                         OutputIterator result,
                         StrictWeakOrdering)
{
  THRUST_STATIC_ASSERT_MSG(
    (thrust::detail::depend_on_instantiation<InputIterator1, false>::value)
  , "unimplemented for this system"
  );
  return result;
} // end set_union()


} // end namespace generic
} // end namespace detail
} // end namespace system
THRUST_NAMESPACE_END
