// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//

#ifndef _PSTL_NUMERIC_FWD_H
#define _PSTL_NUMERIC_FWD_H

#include <__config>
#include <type_traits>
#include <utility>

namespace __pstl {
namespace __internal {

//------------------------------------------------------------------------
// transform_reduce (version with two binary functions, according to draft N4659)
//------------------------------------------------------------------------

template <class _RandomAccessIterator1,
          class _RandomAccessIterator2,
          class _Tp,
          class _BinaryOperation1,
          class _BinaryOperation2>
_Tp __brick_transform_reduce(
    _RandomAccessIterator1,
    _RandomAccessIterator1,
    _RandomAccessIterator2,
    _Tp,
    _BinaryOperation1,
    _BinaryOperation2,
    /*__is_vector=*/std::true_type) noexcept;

template <class _ForwardIterator1, class _ForwardIterator2, class _Tp, class _BinaryOperation1, class _BinaryOperation2>
_Tp __brick_transform_reduce(
    _ForwardIterator1,
    _ForwardIterator1,
    _ForwardIterator2,
    _Tp,
    _BinaryOperation1,
    _BinaryOperation2,
    /*__is_vector=*/std::false_type) noexcept;

template <class _Tag,
          class _ExecutionPolicy,
          class _ForwardIterator1,
          class _ForwardIterator2,
          class _Tp,
          class _BinaryOperation1,
          class _BinaryOperation2>
_Tp __pattern_transform_reduce(
    _Tag,
    _ExecutionPolicy&&,
    _ForwardIterator1,
    _ForwardIterator1,
    _ForwardIterator2,
    _Tp,
    _BinaryOperation1,
    _BinaryOperation2) noexcept;

template <class _IsVector,
          class _ExecutionPolicy,
          class _RandomAccessIterator1,
          class _RandomAccessIterator2,
          class _Tp,
          class _BinaryOperation1,
          class _BinaryOperation2>
_Tp __pattern_transform_reduce(
    __parallel_tag<_IsVector>,
    _ExecutionPolicy&&,
    _RandomAccessIterator1,
    _RandomAccessIterator1,
    _RandomAccessIterator2,
    _Tp,
    _BinaryOperation1,
    _BinaryOperation2);

//------------------------------------------------------------------------
// transform_reduce (version with unary and binary functions)
//------------------------------------------------------------------------

template <class _RandomAccessIterator, class _Tp, class _UnaryOperation, class _BinaryOperation>
_Tp __brick_transform_reduce(
    _RandomAccessIterator,
    _RandomAccessIterator,
    _Tp,
    _BinaryOperation,
    _UnaryOperation,
    /*is_vector=*/std::true_type) noexcept;

template <class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
_Tp __brick_transform_reduce(
    _ForwardIterator,
    _ForwardIterator,
    _Tp,
    _BinaryOperation,
    _UnaryOperation,
    /*is_vector=*/std::false_type) noexcept;

template <class _Tag,
          class _ExecutionPolicy,
          class _ForwardIterator,
          class _Tp,
          class _BinaryOperation,
          class _UnaryOperation>
_Tp __pattern_transform_reduce(
    _Tag, _ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Tp, _BinaryOperation, _UnaryOperation) noexcept;

template <class _IsVector,
          class _ExecutionPolicy,
          class _RandomAccessIterator,
          class _Tp,
          class _BinaryOperation,
          class _UnaryOperation>
_Tp __pattern_transform_reduce(
    __parallel_tag<_IsVector>,
    _ExecutionPolicy&&,
    _RandomAccessIterator,
    _RandomAccessIterator,
    _Tp,
    _BinaryOperation,
    _UnaryOperation);

//------------------------------------------------------------------------
// transform_exclusive_scan
//
// walk3 evaluates f(x,y,z) for (x,y,z) drawn from [first1,last1), [first2,...), [first3,...)
//------------------------------------------------------------------------

template <class _ForwardIterator, class _OutputIterator, class _UnaryOperation, class _Tp, class _BinaryOperation>
std::pair<_OutputIterator, _Tp> __brick_transform_scan(
    _ForwardIterator,
    _ForwardIterator,
    _OutputIterator,
    _UnaryOperation,
    _Tp,
    _BinaryOperation,
    /*Inclusive*/ std::false_type) noexcept;

template <class _RandomAccessIterator, class _OutputIterator, class _UnaryOperation, class _Tp, class _BinaryOperation>
std::pair<_OutputIterator, _Tp> __brick_transform_scan(
    _RandomAccessIterator,
    _RandomAccessIterator,
    _OutputIterator,
    _UnaryOperation,
    _Tp,
    _BinaryOperation,
    /*Inclusive*/ std::true_type) noexcept;

template <class _Tag,
          class _ExecutionPolicy,
          class _ForwardIterator,
          class _OutputIterator,
          class _UnaryOperation,
          class _Tp,
          class _BinaryOperation,
          class _Inclusive>
_OutputIterator __pattern_transform_scan(
    _Tag,
    _ExecutionPolicy&&,
    _ForwardIterator,
    _ForwardIterator,
    _OutputIterator,
    _UnaryOperation,
    _Tp,
    _BinaryOperation,
    _Inclusive) noexcept;

template <class _IsVector,
          class _ExecutionPolicy,
          class _RandomAccessIterator,
          class _OutputIterator,
          class _UnaryOperation,
          class _Tp,
          class _BinaryOperation,
          class _Inclusive>
typename std::enable_if<!std::is_floating_point<_Tp>::value, _OutputIterator>::type __pattern_transform_scan(
    __parallel_tag<_IsVector> __tag,
    _ExecutionPolicy&&,
    _RandomAccessIterator,
    _RandomAccessIterator,
    _OutputIterator,
    _UnaryOperation,
    _Tp,
    _BinaryOperation,
    _Inclusive);

template <class _IsVector,
          class _ExecutionPolicy,
          class _RandomAccessIterator,
          class _OutputIterator,
          class _UnaryOperation,
          class _Tp,
          class _BinaryOperation,
          class _Inclusive>
typename std::enable_if<std::is_floating_point<_Tp>::value, _OutputIterator>::type __pattern_transform_scan(
    __parallel_tag<_IsVector>,
    _ExecutionPolicy&&,
    _RandomAccessIterator,
    _RandomAccessIterator,
    _OutputIterator,
    _UnaryOperation,
    _Tp,
    _BinaryOperation,
    _Inclusive);

//------------------------------------------------------------------------
// adjacent_difference
//------------------------------------------------------------------------

template <class _ForwardIterator, class _OutputIterator, class _BinaryOperation>
_OutputIterator __brick_adjacent_difference(
    _ForwardIterator,
    _ForwardIterator,
    _OutputIterator,
    _BinaryOperation,
    /*is_vector*/ std::false_type) noexcept;

template <class _RandomAccessIterator, class _OutputIterator, class _BinaryOperation>
_OutputIterator __brick_adjacent_difference(
    _RandomAccessIterator,
    _RandomAccessIterator,
    _OutputIterator,
    _BinaryOperation,
    /*is_vector*/ std::true_type) noexcept;

template <class _Tag, class _ExecutionPolicy, class _ForwardIterator, class _OutputIterator, class _BinaryOperation>
_OutputIterator __pattern_adjacent_difference(
    _Tag, _ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _OutputIterator, _BinaryOperation) noexcept;

template <class _IsVector,
          class _ExecutionPolicy,
          class _RandomAccessIterator,
          class _OutputIterator,
          class _BinaryOperation>
_OutputIterator __pattern_adjacent_difference(
    __parallel_tag<_IsVector>,
    _ExecutionPolicy&&,
    _RandomAccessIterator,
    _RandomAccessIterator,
    _OutputIterator,
    _BinaryOperation);

} // namespace __internal
} // namespace __pstl

#endif /* _PSTL_NUMERIC_FWD_H */