//===----------------------------------------------------------------------===//
//
// Part of libcu++, the C++ Standard Library for your entire system,
// under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// SPDX-FileCopyrightText: Copyright (c) 2023 NVIDIA CORPORATION & AFFILIATES.
//
//===----------------------------------------------------------------------===//

// <algorithm>

// template<InputIterator InIter, class OutIter>
//   requires OutputIterator<OutIter, RvalueOf<InIter::value_type>::type>
//         && EqualityComparable<InIter::value_type>
//         && HasAssign<InIter::value_type, InIter::reference>
//         && Constructible<InIter::value_type, InIter::reference>
//   constexpr OutIter        // constexpr after C++17
//   unique_copy(InIter first, InIter last, OutIter result);

#include <cuda/std/__algorithm_>
#include <cuda/std/cassert>

#include "MoveOnly.h"
#include "test_iterators.h"
#include "test_macros.h"

struct AssignableFromMoveOnly
{
  __host__ __device__ constexpr AssignableFromMoveOnly(int i)
      : data(i)
  {}
  __host__ __device__ constexpr AssignableFromMoveOnly()
      : data(0)
  {}
  int data;
  __host__ __device__ constexpr AssignableFromMoveOnly& operator=(MoveOnly const& m)
  {
    data = m.get();
    return *this;
  }
  __host__ __device__ constexpr bool operator==(AssignableFromMoveOnly const& rhs) const
  {
    return data == rhs.data;
  }
};

template <class InIter, class OutIter>
__host__ __device__ constexpr void test()
{
  const int ia[]    = {0};
  const unsigned sa = sizeof(ia) / sizeof(ia[0]);
  int ja[sa]        = {-1};
  OutIter r         = cuda::std::unique_copy(InIter(ia), InIter(ia + sa), OutIter(ja));
  assert(base(r) == ja + sa);
  assert(ja[0] == 0);

  const int ib[]    = {0, 1};
  const unsigned sb = sizeof(ib) / sizeof(ib[0]);
  int jb[sb]        = {-1};
  r                 = cuda::std::unique_copy(InIter(ib), InIter(ib + sb), OutIter(jb));
  assert(base(r) == jb + sb);
  assert(jb[0] == 0);
  assert(jb[1] == 1);

  const int ic[]    = {0, 0};
  const unsigned sc = sizeof(ic) / sizeof(ic[0]);
  int jc[sc]        = {-1};
  r                 = cuda::std::unique_copy(InIter(ic), InIter(ic + sc), OutIter(jc));
  assert(base(r) == jc + 1);
  assert(jc[0] == 0);

  const int id[]    = {0, 0, 1};
  const unsigned sd = sizeof(id) / sizeof(id[0]);
  int jd[sd]        = {-1};
  r                 = cuda::std::unique_copy(InIter(id), InIter(id + sd), OutIter(jd));
  assert(base(r) == jd + 2);
  assert(jd[0] == 0);
  assert(jd[1] == 1);

  const int ie[]    = {0, 0, 1, 0};
  const unsigned se = sizeof(ie) / sizeof(ie[0]);
  int je[se]        = {-1};
  r                 = cuda::std::unique_copy(InIter(ie), InIter(ie + se), OutIter(je));
  assert(base(r) == je + 3);
  assert(je[0] == 0);
  assert(je[1] == 1);
  assert(je[2] == 0);

  const int ig[]    = {0, 0, 1, 1};
  const unsigned sg = sizeof(ig) / sizeof(ig[0]);
  int jg[sg]        = {-1};
  r                 = cuda::std::unique_copy(InIter(ig), InIter(ig + sg), OutIter(jg));
  assert(base(r) == jg + 2);
  assert(jg[0] == 0);
  assert(jg[1] == 1);

  const int ih[]    = {0, 1, 1};
  const unsigned sh = sizeof(ih) / sizeof(ih[0]);
  int jh[sh]        = {-1};
  r                 = cuda::std::unique_copy(InIter(ih), InIter(ih + sh), OutIter(jh));
  assert(base(r) == jh + 2);
  assert(jh[0] == 0);
  assert(jh[1] == 1);

  const int ii[]    = {0, 1, 1, 1, 2, 2, 2};
  const unsigned si = sizeof(ii) / sizeof(ii[0]);
  int ji[si]        = {-1};
  r                 = cuda::std::unique_copy(InIter(ii), InIter(ii + si), OutIter(ji));
  assert(base(r) == ji + 3);
  assert(ji[0] == 0);
  assert(ji[1] == 1);
  assert(ji[2] == 2);
}

__host__ __device__ constexpr bool test()
{
  test<cpp17_input_iterator<const int*>, cpp17_input_iterator<int*>>();
  test<cpp17_input_iterator<const int*>, cpp17_output_iterator<int*>>();
  test<cpp17_input_iterator<const int*>, forward_iterator<int*>>();
  test<cpp17_input_iterator<const int*>, bidirectional_iterator<int*>>();
  test<cpp17_input_iterator<const int*>, random_access_iterator<int*>>();
  test<cpp17_input_iterator<const int*>, int*>();

  test<forward_iterator<const int*>, cpp17_output_iterator<int*>>();
  test<forward_iterator<const int*>, forward_iterator<int*>>();
  test<forward_iterator<const int*>, bidirectional_iterator<int*>>();
  test<forward_iterator<const int*>, random_access_iterator<int*>>();
  test<forward_iterator<const int*>, int*>();

  test<bidirectional_iterator<const int*>, cpp17_output_iterator<int*>>();
  test<bidirectional_iterator<const int*>, forward_iterator<int*>>();
  test<bidirectional_iterator<const int*>, bidirectional_iterator<int*>>();
  test<bidirectional_iterator<const int*>, random_access_iterator<int*>>();
  test<bidirectional_iterator<const int*>, int*>();

  test<random_access_iterator<const int*>, cpp17_output_iterator<int*>>();
  test<random_access_iterator<const int*>, forward_iterator<int*>>();
  test<random_access_iterator<const int*>, bidirectional_iterator<int*>>();
  test<random_access_iterator<const int*>, random_access_iterator<int*>>();
  test<random_access_iterator<const int*>, int*>();

  test<const int*, cpp17_output_iterator<int*>>();
  test<const int*, forward_iterator<int*>>();
  test<const int*, bidirectional_iterator<int*>>();
  test<const int*, random_access_iterator<int*>>();
  test<const int*, int*>();

  // Move only inputs
  {
    MoveOnly in[5]                     = {1, 3, 3, 3, 1};
    AssignableFromMoveOnly out[3]      = {};
    auto result                        = cuda::std::unique_copy(in, in + 5, out);
    AssignableFromMoveOnly expected[3] = {1, 3, 1};
    assert(cuda::std::equal(out, out + 3, expected));
    assert(result == out + 3);
  }

  return true;
}

int main(int, char**)
{
  test();
  static_assert(test(), "");

  return 0;
}
