/*
 *  Copyright 2008-2013 NVIDIA Corporation
 *  Modifications Copyright© 2019 Advanced Micro Devices, Inc. All rights reserved.
 *
 *  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.
 */
 
#include <unittest/unittest.h>
#include <thrust/reverse.h>
#include <thrust/iterator/discard_iterator.h>
#include <thrust/iterator/retag.h>


typedef unittest::type_list<unittest::int8_t,unittest::int16_t,unittest::int32_t> ReverseTypes;

template<typename Vector>
void TestReverseSimple(void)
{
  Vector data(5);
  data[0] = 1;
  data[1] = 2;
  data[2] = 3;
  data[3] = 4;
  data[4] = 5;

  thrust::reverse(data.begin(), data.end());

  Vector ref(5);
  ref[0] = 5;
  ref[1] = 4;
  ref[2] = 3;
  ref[3] = 2;
  ref[4] = 1;

  ASSERT_EQUAL(ref, data);
}
DECLARE_VECTOR_UNITTEST(TestReverseSimple);


template<typename BidirectionalIterator>
void reverse(my_system &system,
             BidirectionalIterator,
             BidirectionalIterator)
{
  system.validate_dispatch();
}

void TestReverseDispatchExplicit()
{
  thrust::device_vector<int> vec(1);

  my_system sys(0);
  thrust::reverse(sys, vec.begin(), vec.begin());

  ASSERT_EQUAL(true, sys.is_valid());
}
DECLARE_UNITTEST(TestReverseDispatchExplicit);


template<typename BidirectionalIterator>
void reverse(my_tag,
             BidirectionalIterator first,
             BidirectionalIterator)
{
  *first = 13;
}

void TestReverseDispatchImplicit()
{
  thrust::device_vector<int> vec(1);

  thrust::reverse(thrust::retag<my_tag>(vec.begin()),
                  thrust::retag<my_tag>(vec.begin()));

  ASSERT_EQUAL(13, vec.front());
}
DECLARE_UNITTEST(TestReverseDispatchImplicit);


template<typename Vector>
void TestReverseCopySimple(void)
{
#if THRUST_HOST_COMPILER == THRUST_HOST_COMPILER_GCC && \
    THRUST_GCC_VERSION >= 80000 && THRUST_GCC_VERSION < 100000

  if (typeid(Vector) == typeid(thrust::host_vector<custom_numeric>))
  {
    KNOWN_FAILURE // WAR NVBug 2481122
  }

#endif

  typedef typename Vector::iterator   Iterator;

  Vector input(5);
  input[0] = 1;
  input[1] = 2;
  input[2] = 3;
  input[3] = 4;
  input[4] = 5;

  Vector output(5);

  Iterator iter = thrust::reverse_copy(input.begin(), input.end(), output.begin());

  Vector ref(5);
  ref[0] = 5;
  ref[1] = 4;
  ref[2] = 3;
  ref[3] = 2;
  ref[4] = 1;

  ASSERT_EQUAL(5, iter - output.begin());
  ASSERT_EQUAL(ref, output);
}
DECLARE_VECTOR_UNITTEST(TestReverseCopySimple);


template<typename BidirectionalIterator, typename OutputIterator>
OutputIterator reverse_copy(my_system &system,
                            BidirectionalIterator,
                            BidirectionalIterator,
                            OutputIterator result)
{
  system.validate_dispatch();
  return result;
}

void TestReverseCopyDispatchExplicit()
{
  thrust::device_vector<int> vec(1);

  my_system sys(0);
  thrust::reverse_copy(sys, vec.begin(), vec.end(), vec.begin());

  ASSERT_EQUAL(true, sys.is_valid());
}
DECLARE_UNITTEST(TestReverseCopyDispatchExplicit);


template<typename BidirectionalIterator, typename OutputIterator>
OutputIterator reverse_copy(my_tag,
                            BidirectionalIterator,
                            BidirectionalIterator,
                            OutputIterator result)
{
  *result = 13;
  return result;
}

void TestReverseCopyDispatchImplicit()
{
  thrust::device_vector<int> vec(1);

  thrust::reverse_copy(thrust::retag<my_tag>(vec.begin()),
                       thrust::retag<my_tag>(vec.end()),
                       thrust::retag<my_tag>(vec.begin()));

  ASSERT_EQUAL(13, vec.front());
}
DECLARE_UNITTEST(TestReverseCopyDispatchImplicit);


template<typename T>
struct TestReverse
{
  void operator()(const size_t n)
  {
    thrust::host_vector<T> h_data = unittest::random_integers<T>(n);
    thrust::device_vector<T> d_data = h_data;

    thrust::reverse(h_data.begin(), h_data.end());
    thrust::reverse(d_data.begin(), d_data.end());

    ASSERT_EQUAL(h_data, d_data);
  }
};
VariableUnitTest<TestReverse, ReverseTypes> TestReverseInstance;

template<typename T>
struct TestReverseCopy
{
  void operator()(const size_t n)
  {
    thrust::host_vector<T> h_data = unittest::random_integers<T>(n);
    thrust::device_vector<T> d_data = h_data;

    thrust::host_vector<T> h_result(n);
    thrust::device_vector<T> d_result(n);

    thrust::reverse_copy(h_data.begin(), h_data.end(), h_result.begin());
    thrust::reverse_copy(d_data.begin(), d_data.end(), d_result.begin());

    ASSERT_EQUAL(h_result, d_result);
  }
};
VariableUnitTest<TestReverseCopy, ReverseTypes> TestReverseCopyInstance;

template<typename T>
struct TestReverseCopyToDiscardIterator
{
  void operator()(const size_t n)
  {
    thrust::host_vector<T> h_data = unittest::random_integers<T>(n);
    thrust::device_vector<T> d_data = h_data;

    thrust::discard_iterator<> h_result =
      thrust::reverse_copy(h_data.begin(), h_data.end(), thrust::make_discard_iterator());

    thrust::discard_iterator<> d_result =
      thrust::reverse_copy(d_data.begin(), d_data.end(), thrust::make_discard_iterator());

    thrust::discard_iterator<> reference(n);

    ASSERT_EQUAL_QUIET(reference, h_result);
    ASSERT_EQUAL_QUIET(reference, d_result);
  }
};
VariableUnitTest<TestReverseCopyToDiscardIterator, ReverseTypes> TestReverseCopyToDiscardIteratorInstance;
