//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, 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
//
//===----------------------------------------------------------------------===//

// MIT License
//
// Modifications Copyright (C) 2025 Advanced Micro Devices, Inc. All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

// UNSUPPORTED: no-localization
// UNSUPPORTED: nvrtc, hiprtc

// <complex>

// template<class T, class charT, class traits>
//   basic_ostream<charT, traits>&
//   operator<<(basic_ostream<charT, traits>& o, const complex<T>& x);

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

#include <sstream>

#include "test_macros.h"

template <class T>
void test()
{
  // Basic test
  {
    cuda::std::complex<T> const c(1, 2);
    std::ostringstream os;
    os << c;
    assert(os.str() == "(1,2)");
  }

  // Test with various widths.
  // In particular, make sure the width() is 0 after the operation, which
  // should be the case because [complex.ops] says about operator<< for complex:
  //
  //   Effects: Inserts the complex number x onto the stream o as if it
  //   were implemented as follows:
  //
  //     basic_ostringstream<charT, traits> s;
  //     s.flags(o.flags());
  //     s.imbue(o.getloc());
  //     s.precision(o.precision());
  //     s << '(' << x.real() << "," << x.imag() << ')';
  //     return o << s.str();
  //
  // Since operator<< for std::string sets o.width(0), operator<< for
  // std::complex should do the same.
  {
    for (int width = 0; width <= 5; ++width)
    {
      cuda::std::complex<T> const c(1, 2);
      std::ostringstream os;
      os.width(width);
      os.fill('_');
      os << c;
      assert(os.width() == 0);
      assert(os.str() == "(1,2)");
    }
    {
      cuda::std::complex<T> const c(1, 2);
      std::ostringstream os;
      os.width(6);
      os.fill('_');
      os << c;
      assert(os.width() == 0);
      assert(os.str() == "_(1,2)");
    }
    {
      cuda::std::complex<T> const c(1, 2);
      std::ostringstream os;
      os.width(7);
      os.fill('_');
      os << c;
      assert(os.width() == 0);
      assert(os.str() == "__(1,2)");
    }
    {
      cuda::std::complex<T> const c(1, 2);
      std::ostringstream os;
      os.width(8);
      os.fill('_');
      os << c;
      assert(os.width() == 0);
      assert(os.str() == "___(1,2)");
    }
    // Insert something after the complex and make sure the
    // stream's width has been reset as expected.
    {
      cuda::std::complex<T> const c(1, 2);
      std::ostringstream os;
      os.width(8);
      os.fill('_');
      os << c;
      assert(os.width() == 0);

      os << "hello";
      assert(os.str() == "___(1,2)hello");
    }

    // Test with numbers that result in different output lengths, to
    // make sure we handle custom width() correctly.
    {
      cuda::std::complex<T> const c(123, 456);
      std::ostringstream os;
      os.width(4);
      os.fill('_');
      os << c;
      assert(os.width() == 0);
      assert(os.str() == "(123,456)");
    }
    {
      cuda::std::complex<T> const c(123, 456);
      std::ostringstream os;
      os.width(12);
      os.fill('_');
      os << c;
      assert(os.width() == 0);
      assert(os.str() == "___(123,456)");

      os << "hello";
      assert(os.str() == "___(123,456)hello");
    }

    // Make sure left fill behaves correctly
    {
      cuda::std::complex<T> const c(123, 456);
      std::ostringstream os;
      os.width(12);
      os.fill('_');
      os << std::left << c;
      assert(os.width() == 0);
      assert(os.str() == "(123,456)___");

      os << "xy";
      assert(os.str() == "(123,456)___xy");
    }
  }
}

void test()
{
  test<float>();
  test<double>();
#if _LIBCUDACXX_HAS_NVFP16()
  test<__half>();
#endif // _LIBCUDACXX_HAS_NVFP16()
#if _LIBCUDACXX_HAS_NVBF16()
  test<__nv_bfloat16>();
#endif // _LIBCUDACXX_HAS_NVBF16()
}

int main(int, char**)
{
  NV_IF_TARGET(NV_IS_HOST, test();)
  return 0;
}
