// Copyright (c) 2015 Amanieu d'Antras
//
// 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.

namespace async {
namespace detail {

// Allocate an aligned block of memory
LIBASYNC_EXPORT void* aligned_alloc(std::size_t size, std::size_t align);

// Free an aligned block of memory
LIBASYNC_EXPORT void aligned_free(void* addr) LIBASYNC_NOEXCEPT;

// Class representing an aligned array and its length
template<typename T, std::size_t Align = std::alignment_of<T>::value>
class aligned_array {
	std::size_t length;
	T* ptr;

public:
	aligned_array()
		: length(0), ptr(nullptr) {}
	aligned_array(std::nullptr_t)
		: length(0), ptr(nullptr) {}
	explicit aligned_array(std::size_t length_)
		: length(length_)
	{
		ptr = static_cast<T*>(aligned_alloc(length * sizeof(T), Align));
		std::size_t i;
		LIBASYNC_TRY {
			for (i = 0; i < length; i++)
				new(ptr + i) T;
		} LIBASYNC_CATCH(...) {
			for (std::size_t j = 0; j < i; j++)
				ptr[i].~T();
			aligned_free(ptr);
			LIBASYNC_RETHROW();
		}
	}
	aligned_array(aligned_array&& other) LIBASYNC_NOEXCEPT
		: length(other.length), ptr(other.ptr)
	{
		other.ptr = nullptr;
		other.length = 0;
	}
	aligned_array& operator=(aligned_array&& other) LIBASYNC_NOEXCEPT
	{
		aligned_array(std::move(*this));
		std::swap(ptr, other.ptr);
		std::swap(length, other.length);
		return *this;
	}
	aligned_array& operator=(std::nullptr_t)
	{
		return *this = aligned_array();
	}
	~aligned_array()
	{
		for (std::size_t i = 0; i < length; i++)
			ptr[i].~T();
		aligned_free(ptr);
	}

	T& operator[](std::size_t i) const
	{
		return ptr[i];
	}
	std::size_t size() const
	{
		return length;
	}
	T* get() const
	{
		return ptr;
	}
	explicit operator bool() const
	{
		return ptr != nullptr;
	}
};

} // namespace detail
} // namespace async