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#pragma once

#if THRUST_DEVICE_COMPILER == THRUST_DEVICE_COMPILER_HCC
#include <iterator>
#include <thrust/distance.h>
#include <thrust/system/hip/detail/scan.h>

// rocprim include
#include <rocprim/rocprim.hpp>
#include <thrust/detail/alignment.h>
#include <thrust/detail/cstdint.h>

BEGIN_NS_THRUST

namespace hip_rocprim
{

template <class Derived, class InputIt, class OutputIt, class TransformOp, class ScanOp>
OutputIt THRUST_HIP_FUNCTION
transform_inclusive_scan(execution_policy<Derived>& policy,
                         InputIt                    first,
                         InputIt                    last,
                         OutputIt                   result,
                         TransformOp                transform_op,
                         ScanOp                     scan_op)
{
    // the pseudocode for deducing the type of the temporary used below:
    //
    // if UnaryFunction is AdaptableUnaryFunction
    //   TemporaryType = AdaptableUnaryFunction::result_type
    // else if OutputIterator is a "pure" output iterator
    //   TemporaryType = InputIterator::value_type
    // else
    //   TemporaryType = OutputIterator::value_type
    //
    // XXX upon c++0x, TemporaryType needs to be:
    // result_of_adaptable_function<UnaryFunction>::type
    typedef typename detail::eval_if<detail::has_result_type<TransformOp>::value,
                                     detail::result_type<TransformOp>,
                                     detail::eval_if<detail::is_output_iterator<OutputIt>::value,
                                                     iterator_value<InputIt>,
                                                     iterator_value<OutputIt>>>::type result_type;

    typedef typename iterator_traits<InputIt>::difference_type size_type;
    size_type num_items = static_cast<size_type>(thrust::distance(first, last));
    typedef transform_input_iterator_t<result_type, InputIt, TransformOp>
        transformed_iterator_t;

    return hip_rocprim::inclusive_scan_n(
        policy, transformed_iterator_t(first, transform_op), num_items, result, scan_op
    );
}

template <class Derived,
          class InputIt,
          class OutputIt,
          class TransformOp,
          class T,
          class ScanOp>
OutputIt THRUST_HIP_FUNCTION
transform_exclusive_scan(execution_policy<Derived>& policy,
                         InputIt                    first,
                         InputIt                    last,
                         OutputIt                   result,
                         TransformOp                transform_op,
                         T                          init,
                         ScanOp                     scan_op)
{
    // the pseudocode for deducing the type of the temporary used below:
    //
    // if UnaryFunction is AdaptableUnaryFunction
    //   TemporaryType = AdaptableUnaryFunction::result_type
    // else if OutputIterator is a "pure" output iterator
    //   TemporaryType = InputIterator::value_type
    // else
    //   TemporaryType = OutputIterator::value_type
    //
    // XXX upon c++0x, TemporaryType needs to be:
    // result_of_adaptable_function<UnaryFunction>::type

    typedef typename thrust::detail::eval_if<
            thrust::detail::has_result_type<TransformOp>::value,
            thrust::detail::result_type<TransformOp>,
            thrust::detail::eval_if<thrust::detail::is_output_iterator<OutputIt>::value,
                                    thrust::iterator_value<InputIt>,
                                    thrust::iterator_value<OutputIt>>>::type result_type;

    typedef typename iterator_traits<InputIt>::difference_type size_type;
    size_type num_items = static_cast<size_type>(thrust::distance(first, last));
    typedef transform_input_iterator_t<result_type, InputIt, TransformOp>
        transformed_iterator_t;

    return hip_rocprim::exclusive_scan_n(
        policy, transformed_iterator_t(first, transform_op), num_items, result, init, scan_op
    );
}

} // namespace hip_rocprim

END_NS_THRUST
#endif