/*
 *  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_ptr.h>
#include <thrust/device_vector.h>
#include <thrust/functional.h>
#include <thrust/iterator/counting_iterator.h>
#include <thrust/iterator/transform_iterator.h>

#include "test_header.hpp"

template <typename Iterator1, typename Iterator2>
__global__
THRUST_HIP_LAUNCH_BOUNDS_DEFAULT
void simple_copy_on_device(Iterator1 first1, Iterator1 last1, Iterator2 first2)
{
    while(first1 != last1)
        *(first2++) = *(first1++);
}

template <typename Iterator1, typename Iterator2>
void simple_copy(Iterator1 first1, Iterator1 last1, Iterator2 first2)
{
    hipLaunchKernelGGL(HIP_KERNEL_NAME(simple_copy_on_device<Iterator1, Iterator2>),
                       dim3(1),
                       dim3(1),
                       0,
                       0,
                       first1,
                       last1,
                       first2);
}

TEST(DereferenceTests, TestDeviceDereferenceDeviceVectorIterator)
{
    SCOPED_TRACE(testing::Message() << "with device_id= " << test::set_device_from_ctest());

    for(auto seed : get_seeds())
    {
        SCOPED_TRACE(testing::Message() << "with seed= " << seed);

        thrust::device_vector<int> input = get_random_data<int>(
            100, std::numeric_limits<int>::min(), std::numeric_limits<int>::max(), seed);
        thrust::device_vector<int> output(input.size(), 0);

        simple_copy(input.begin(), input.end(), output.begin());

        ASSERT_EQ(input, output);
    }
}

TEST(DereferenceTests, TestDeviceDereferenceDevicePtr)
{
    SCOPED_TRACE(testing::Message() << "with device_id= " << test::set_device_from_ctest());

    for(auto seed : get_seeds())
    {
        SCOPED_TRACE(testing::Message() << "with seed= " << seed);

        thrust::device_vector<int> input = get_random_data<int>(
            100, std::numeric_limits<int>::min(), std::numeric_limits<int>::max(), seed);
        thrust::device_vector<int> output(input.size(), 0);

        thrust::device_ptr<int> _first1 = &input[0];
        thrust::device_ptr<int> _last1  = _first1 + input.size();
        thrust::device_ptr<int> _first2 = &output[0];

        simple_copy(_first1, _last1, _first2);

        ASSERT_EQ(input, output);
    }
}

TEST(DereferenceTests, TestDeviceDereferenceTransformIterator)
{
    SCOPED_TRACE(testing::Message() << "with device_id= " << test::set_device_from_ctest());

    for(auto seed : get_seeds())
    {
        SCOPED_TRACE(testing::Message() << "with seed= " << seed);

        thrust::device_vector<int> input = get_random_data<int>(
            100, std::numeric_limits<int>::min(), std::numeric_limits<int>::max(), seed);
        thrust::device_vector<int> output(input.size(), 0);

        simple_copy(thrust::make_transform_iterator(input.begin(), thrust::identity<int>()),
                    thrust::make_transform_iterator(input.end(), thrust::identity<int>()),
                    output.begin());

        ASSERT_EQ(input, output);
    }
}

TEST(DereferenceTests, TestDeviceDereferenceCountingIterator)
{
    SCOPED_TRACE(testing::Message() << "with device_id= " << test::set_device_from_ctest());

    thrust::counting_iterator<int> first(1);
    thrust::counting_iterator<int> last(6);

    thrust::device_vector<int> output(5);

    simple_copy(first, last, output.begin());

    ASSERT_EQ(output[0], 1);
    ASSERT_EQ(output[1], 2);
    ASSERT_EQ(output[2], 3);
    ASSERT_EQ(output[3], 4);
    ASSERT_EQ(output[4], 5);
}

TEST(DereferenceTests, TestDeviceDereferenceTransformedCountingIterator)
{
    SCOPED_TRACE(testing::Message() << "with device_id= " << test::set_device_from_ctest());
    
    thrust::counting_iterator<int> first(1);
    thrust::counting_iterator<int> last(6);

    thrust::device_vector<int> output(5);

    simple_copy(thrust::make_transform_iterator(first, thrust::negate<int>()),
                thrust::make_transform_iterator(last, thrust::negate<int>()),
                output.begin());

    ASSERT_EQ(output[0], -1);
    ASSERT_EQ(output[1], -2);
    ASSERT_EQ(output[2], -3);
    ASSERT_EQ(output[3], -4);
    ASSERT_EQ(output[4], -5);
}