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#pragma once

#if THRUST_DEVICE_COMPILER == THRUST_DEVICE_COMPILER_HIP
#include <thrust/system/hip/config.h>


#include <thrust/detail/cstdint.h>
#include <thrust/detail/temporary_array.h>
#include <thrust/system/hip/detail/par_to_seq.h>
#include <thrust/system/hip/detail/util.h>
#include <thrust/system/hip/detail/get_value.h>
#include <thrust/functional.h>
#include <thrust/detail/mpl/math.h>
#include <thrust/detail/minmax.h>
#include <thrust/distance.h>

// rocPRIM includes
#include <rocprim/rocprim.hpp>

THRUST_NAMESPACE_BEGIN

template <typename DerivedPolicy, typename ForwardIterator, typename BinaryPredicate>
ForwardIterator __host__ __device__
unique(const thrust::detail::execution_policy_base<DerivedPolicy>& exec,
       ForwardIterator                                             first,
       ForwardIterator                                             last,
       BinaryPredicate                                             binary_pred);

template <typename DerivedPolicy,
          typename InputIterator,
          typename OutputIterator,
          typename BinaryPredicate>
__host__ __device__ OutputIterator
unique_copy(const thrust::detail::execution_policy_base<DerivedPolicy>& exec,
            InputIterator                                               first,
            InputIterator                                               last,
            OutputIterator                                              result,
            BinaryPredicate                                             binary_pred);

namespace hip_rocprim
{
namespace __unique
{
    template <typename Derived,
	      typename ItemsInputIt,
	      typename ItemsOutputIt,
              typename BinaryPred>
    THRUST_HIP_RUNTIME_FUNCTION
    ItemsOutputIt unique(execution_policy<Derived>& policy,
                         ItemsInputIt               items_first,
                         ItemsInputIt               items_last,
                         ItemsOutputIt              items_result,
                         BinaryPred                 binary_pred)
    {
        typedef size_t size_type;

        size_type num_items = static_cast<size_type>(thrust::distance(items_first, items_last));
        size_t    temp_storage_bytes   = 0;
        hipStream_t stream             = hip_rocprim::stream(policy);
        bool        debug_sync         = THRUST_HIP_DEBUG_SYNC_FLAG;

        if(num_items == 0)
            return items_result;

        // Determine temporary device storage requirements.
        hip_rocprim::throw_on_error(rocprim::unique(NULL,
                                                    temp_storage_bytes,
                                                    items_first,
                                                    items_result,
                                                    reinterpret_cast<size_type*>(NULL),
                                                    num_items,
                                                    binary_pred,
                                                    stream,
                                                    debug_sync),
                                    "unique failed on 1st step");

        // Allocate temporary storage.
        thrust::detail::temporary_array<thrust::detail::uint8_t, Derived>
            tmp(policy, temp_storage_bytes + sizeof(size_type));
        void *ptr = static_cast<void*>(tmp.data().get());

        size_type* d_num_selected_out = reinterpret_cast<size_type*>(
            reinterpret_cast<char*>(ptr) + temp_storage_bytes);

        hip_rocprim::throw_on_error(rocprim::unique(ptr,
                                                    temp_storage_bytes,
                                                    items_first,
                                                    items_result,
                                                    d_num_selected_out,
                                                    num_items,
                                                    binary_pred,
                                                    stream,
                                                    debug_sync),
                                    "unique failed on 2nd step");

        size_type num_selected = get_value(policy, d_num_selected_out);

        return items_result + num_selected;
    }
} // namespace __unique

//-------------------------
// Thrust API entry points
//-------------------------

__thrust_exec_check_disable__ template <class Derived,
                                        class InputIt,
                                        class OutputIt,
                                        class BinaryPred>
OutputIt THRUST_HIP_FUNCTION
unique_copy(execution_policy<Derived>& policy,
            InputIt                    first,
            InputIt                    last,
            OutputIt                   result,
            BinaryPred                 binary_pred)
{
  // struct workaround is required for HIP-clang
  // THRUST_HIP_PRESERVE_KERNELS_WORKAROUND is required for HCC
  struct workaround
  {
      __host__
      static OutputIt par(execution_policy<Derived>& policy,
                   InputIt                    first,
                   InputIt                    last,
                   OutputIt                   result,
                   BinaryPred                 binary_pred)
      {
      #if __HCC__ && __HIP_DEVICE_COMPILE__
        THRUST_HIP_PRESERVE_KERNELS_WORKAROUND(__unique::unique<Derived, InputIt, OutputIt, BinaryPred>);
      #else
        return __unique::unique(policy, first, last, result, binary_pred);
      #endif
      }
      __device__
      static OutputIt seq(execution_policy<Derived>& policy,
                   InputIt                    first,
                   InputIt                    last,
                   OutputIt                   result,
                   BinaryPred                 binary_pred)
      {
        return thrust::unique_copy
            (
                cvt_to_seq(derived_cast(policy)), first, last, result, binary_pred
            );
      }
  };
  #if __THRUST_HAS_HIPRT__
    return workaround::par(policy, first, last, result, binary_pred);
  #else
    return workaround::seq(policy, first, last, result, binary_pred);
  #endif
}

template <class Derived, class InputIt, class OutputIt>
OutputIt THRUST_HIP_FUNCTION
unique_copy(execution_policy<Derived>& policy, InputIt first, InputIt last, OutputIt result)
{
    typedef typename iterator_traits<InputIt>::value_type input_type;
    return hip_rocprim::unique_copy(policy, first, last, result, equal_to<input_type>());
}

__thrust_exec_check_disable__ template <class Derived, class InputIt, class BinaryPred>
InputIt THRUST_HIP_FUNCTION
unique(execution_policy<Derived>& policy,
       InputIt                    first,
       InputIt                    last,
       BinaryPred                 binary_pred)
{
  // struct workaround is required for HIP-clang
  // THRUST_HIP_PRESERVE_KERNELS_WORKAROUND is required for HCC
  struct workaround
  {
      __host__
      static InputIt par(execution_policy<Derived>& policy,
                         InputIt                    first,
                         InputIt                    last,
                         BinaryPred                 binary_pred)
      {
      #if __HCC__ && __HIP_DEVICE_COMPILE__
          THRUST_HIP_PRESERVE_KERNELS_WORKAROUND(
              (unique_copy<Derived, InputIt, InputIt, BinaryPred>)
          );
      #else
          return hip_rocprim::unique_copy(policy, first, last, first, binary_pred);
      #endif
      }
      __device__
      static InputIt seq(execution_policy<Derived>& policy,
                         InputIt                    first,
                         InputIt                    last,
                         BinaryPred                 binary_pred)
      {
          return thrust::unique(
              cvt_to_seq(derived_cast(policy)), first, last, binary_pred
          );
      }
  };
  #if __THRUST_HAS_HIPRT__
      return workaround::par(policy, first, last, binary_pred);
  #else
      return workaround::seq(policy, first, last, binary_pred);
  #endif
}

template <class Derived, class InputIt>
InputIt THRUST_HIP_FUNCTION unique(execution_policy<Derived>& policy,
                                   InputIt                    first,
                                   InputIt                    last)
{
    typedef typename iterator_traits<InputIt>::value_type input_type;
    return hip_rocprim::unique(policy, first, last, equal_to<input_type>());
}

} // namespace hip_rocprim
THRUST_NAMESPACE_END

#include <thrust/memory.h>
#include <thrust/unique.h>
#endif