/*
 *  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 <thrust/adjacent_difference.h>
#include <thrust/iterator/discard_iterator.h>
#include <thrust/iterator/retag.h>

#include "test_header.hpp"

#if THRUST_DEVICE_COMPILER == THRUST_DEVICE_COMPILER_HCC

TESTS_DEFINE(AdjacentDifferenceTests, FullTestsParams);
TESTS_DEFINE(AdjacentDifferenceVariableTests, NumericalTestsParams);

TYPED_TEST(AdjacentDifferenceTests, TestAdjacentDifferenceSimple)
{
    using Vector = typename TestFixture::input_type;
    using T      = typename Vector::value_type;

    Vector input(3);
    Vector output(3);
    input[0] = 1;
    input[1] = 4;
    input[2] = 6;

    typename Vector::iterator result;

    result = thrust::adjacent_difference(input.begin(), input.end(), output.begin());

    ASSERT_EQ(result - output.begin(), 3);
    ASSERT_EQ(output[0], T(1));
    ASSERT_EQ(output[1], T(3));
    ASSERT_EQ(output[2], T(2));

    result = thrust::adjacent_difference(
        input.begin(), input.end(), output.begin(), thrust::plus<T>());

    ASSERT_EQ(result - output.begin(), 3);
    ASSERT_EQ(output[0], T(1));
    ASSERT_EQ(output[1], T(5));
    ASSERT_EQ(output[2], T(10));

    // test in-place operation, result and first are permitted to be the same
    result = thrust::adjacent_difference(input.begin(), input.end(), input.begin());

    ASSERT_EQ(result - input.begin(), 3);
    ASSERT_EQ(input[0], T(1));
    ASSERT_EQ(input[1], T(3));
    ASSERT_EQ(input[2], T(2));
}

TYPED_TEST(AdjacentDifferenceVariableTests, TestAdjacentDifference)
{
    using T = typename TestFixture::input_type;

    const std::vector<size_t> sizes = get_sizes();
    for(auto size : sizes)
    {
        thrust::host_vector<T> h_input = get_random_data<T>(
            size, std::numeric_limits<T>::min(), std::numeric_limits<T>::max());
        thrust::device_vector<T> d_input = h_input;

        thrust::host_vector<T>   h_output(size);
        thrust::device_vector<T> d_output(size);

        typename thrust::host_vector<T>::iterator   h_result;
        typename thrust::device_vector<T>::iterator d_result;

        h_result = thrust::adjacent_difference(h_input.begin(), h_input.end(), h_output.begin());
        d_result = thrust::adjacent_difference(d_input.begin(), d_input.end(), d_output.begin());

        ASSERT_EQ(h_result - h_output.begin(), size);
        ASSERT_EQ(d_result - d_output.begin(), size);
        ASSERT_EQ_QUIET(h_output, d_output);

        h_result = thrust::adjacent_difference(
            h_input.begin(), h_input.end(), h_output.begin(), thrust::plus<T>());
        d_result = thrust::adjacent_difference(
            d_input.begin(), d_input.end(), d_output.begin(), thrust::plus<T>());

        ASSERT_EQ(h_result - h_output.begin(), size);
        ASSERT_EQ(d_result - d_output.begin(), size);
        ASSERT_EQ_QUIET(h_output, d_output);

        // in-place operation
        h_result = thrust::adjacent_difference(
            h_input.begin(), h_input.end(), h_input.begin(), thrust::plus<T>());
        d_result = thrust::adjacent_difference(
            d_input.begin(), d_input.end(), d_input.begin(), thrust::plus<T>());

        ASSERT_EQ(h_result - h_input.begin(), size);
        ASSERT_EQ(d_result - d_input.begin(), size);
        ASSERT_EQ_QUIET(h_input, h_output); //computed previously
        ASSERT_EQ_QUIET(d_input, d_output); //computed previously
    }
}

TYPED_TEST(AdjacentDifferenceVariableTests, TestAdjacentDifferenceInPlaceWithRelatedIteratorTypes)
{
    using T = typename TestFixture::input_type;

    const std::vector<size_t> sizes = get_sizes();
    for(auto size : sizes)
    {
        thrust::host_vector<T> h_input = get_random_data<T>(
            size, std::numeric_limits<T>::min(), std::numeric_limits<T>::max());
        thrust::device_vector<T> d_input = h_input;

        thrust::host_vector<T>   h_output(size);
        thrust::device_vector<T> d_output(size);

        typename thrust::host_vector<T>::iterator   h_result;
        typename thrust::device_vector<T>::iterator d_result;

        h_result = thrust::adjacent_difference(
            h_input.begin(), h_input.end(), h_output.begin(), thrust::plus<T>());
        d_result = thrust::adjacent_difference(
            d_input.begin(), d_input.end(), d_output.begin(), thrust::plus<T>());

        // in-place operation with different iterator types
        h_result = thrust::adjacent_difference(
            h_input.cbegin(), h_input.cend(), h_input.begin(), thrust::plus<T>());
        d_result = thrust::adjacent_difference(
            d_input.cbegin(), d_input.cend(), d_input.begin(), thrust::plus<T>());

        ASSERT_EQ(h_result - h_input.begin(), size);
        ASSERT_EQ(d_result - d_input.begin(), size);
        ASSERT_EQ_QUIET(h_output, h_input); // reference computed previously
        ASSERT_EQ_QUIET(d_output, d_input); // reference computed previously
    }
}

TYPED_TEST(AdjacentDifferenceVariableTests, TestAdjacentDifferenceDiscardIterator)
{
    using T = typename TestFixture::input_type;

    const std::vector<size_t> sizes = get_sizes();
    for(auto size : sizes)
    {
        thrust::host_vector<T> h_input = get_random_data<T>(
            size, std::numeric_limits<T>::min(), std::numeric_limits<T>::max());
        thrust::device_vector<T> d_input = h_input;

        thrust::discard_iterator<> h_result;
        thrust::discard_iterator<> d_result;

        h_result = thrust::adjacent_difference(
            h_input.begin(), h_input.end(), thrust::make_discard_iterator());
        d_result = thrust::adjacent_difference(
            d_input.begin(), d_input.end(), thrust::make_discard_iterator());

        thrust::discard_iterator<> reference(size);

        ASSERT_EQ_QUIET(reference, h_result);
        ASSERT_EQ_QUIET(reference, d_result);
    }
}

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

TEST(AdjacentDifferenceTests, TestAdjacentDifferenceDispatchExplicit)
{
    thrust::device_vector<int> d_input(1);

    my_system sys(0);
    thrust::adjacent_difference(sys, d_input.begin(), d_input.end(), d_input.begin());

    ASSERT_EQ(true, sys.is_valid());
}

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

TEST(AdjacentDifferenceTests, TestAdjacentDifferenceDispatchImplicit)
{
    thrust::device_vector<int> d_input(1);

    thrust::adjacent_difference(thrust::retag<my_tag>(d_input.begin()),
                                thrust::retag<my_tag>(d_input.end()),
                                thrust::retag<my_tag>(d_input.begin()));

    ASSERT_EQ(13, d_input.front());
}

#endif // THRUST_DEVICE_COMPILER == THRUST_DEVICE_COMPILER_HCC