/*
 *  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/device_vector.h>
#include <thrust/iterator/counting_iterator.h>
#include <thrust/iterator/iterator_traits.h>
#include <thrust/iterator/retag.h>
#include <thrust/transform_reduce.h>

#include "test_header.hpp"

TESTS_DEFINE(TransformReduceTests, FullTestsParams);
TESTS_DEFINE(TransformReduceIntegerTests, VectorSignedIntegerTestsParams);
TESTS_DEFINE(TransformReduceIntegerPrimitiveTests, IntegerTestsParams);

template <typename InputIterator,
          typename UnaryFunction,
          typename OutputType,
          typename BinaryFunction>
__host__ __device__ OutputType transform_reduce(
    my_system& system, InputIterator, InputIterator, UnaryFunction, OutputType init, BinaryFunction)
{
    system.validate_dispatch();
    return init;
}

TEST(TransformReduceTests, TestTransformReduceDispatchExplicit)
{
    thrust::device_vector<int> vec(1);

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

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

template <typename InputIterator,
          typename UnaryFunction,
          typename OutputType,
          typename BinaryFunction>
__host__ __device__ OutputType transform_reduce(
    my_tag, InputIterator first, InputIterator, UnaryFunction, OutputType init, BinaryFunction)
{
    *first = 13;
    return init;
}

TEST(TransformReduceTests, TestTransformReduceDispatchImplicit)
{
    thrust::device_vector<int> vec(1);

    thrust::transform_reduce(
        thrust::retag<my_tag>(vec.begin()), thrust::retag<my_tag>(vec.begin()), 0, 0, 0);

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

TYPED_TEST(TransformReduceTests, TestTransformReduceSimple)
{
    using Vector = typename TestFixture::input_type;
    using T      = typename Vector::value_type;

    Vector data(3);
    data[0] = T(1);
    data[1] = T(-2);
    data[2] = T(3);

    T init   = T(10);
    T result = thrust::transform_reduce(
        data.begin(), data.end(), thrust::negate<T>(), init, thrust::plus<T>());

    ASSERT_EQ(result, T(8));
}

TYPED_TEST(TransformReduceIntegerPrimitiveTests, TestTransformReduce)
{
    using T = typename TestFixture::input_type;

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

        thrust::device_vector<T> d_data = h_data;

        T init = T(13);

        T cpu_result = thrust::transform_reduce(
            h_data.begin(), h_data.end(), thrust::negate<T>(), init, thrust::plus<T>());
        T gpu_result = thrust::transform_reduce(
            d_data.begin(), d_data.end(), thrust::negate<T>(), init, thrust::plus<T>());

        ASSERT_EQ(cpu_result, gpu_result);
    }
}

TYPED_TEST(TransformReduceIntegerPrimitiveTests, TestTransformReduceFromConst)
{
    using T = typename TestFixture::input_type;

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

        thrust::device_vector<T> d_data = h_data;

        T init = T(13);

        T cpu_result = thrust::transform_reduce(
            h_data.cbegin(), h_data.cend(), thrust::negate<T>(), init, thrust::plus<T>());
        T gpu_result = thrust::transform_reduce(
            d_data.cbegin(), d_data.cend(), thrust::negate<T>(), init, thrust::plus<T>());

        ASSERT_EQ(cpu_result, gpu_result);
    }
}

TYPED_TEST(TransformReduceIntegerTests, TestTransformReduceCountingIterator)
{
    using Vector = typename TestFixture::input_type;
    using T      = typename Vector::value_type;
    using space  = typename thrust::iterator_system<typename Vector::iterator>::type;
    if(std::is_signed<T>::value)
    {
        thrust::counting_iterator<T, space> first(1);

        T result = thrust::transform_reduce(
            first, first + 3, thrust::negate<short>(), 0, thrust::plus<short>());

        ASSERT_EQ(result, -6);
    }
}