AuroraRuntime/Include/Aurora/Memory/CppHeapWrapper.hpp

/***
    Copyright (C) 2023 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: CppHeapWrapper.hpp
    Date: 2023-12-22
    Author: Reece
***/
#pragma once

namespace Aurora::Memory
{
    template <class T>
    struct CppHeapWrapper
    {
        using value_type = T;

        using size_type       = size_t;
        using difference_type = ptrdiff_t;

        using propagate_on_container_move_assignment = AuTrueType;
        using is_always_equal = AuTrueType;

    #if defined(AU_LANG_CPP_17)
        using pointer         = T *;
        using const_pointer   = const T *;

        using reference       = T &;
        using const_reference = const T &;

        template <class Z>
        struct rebind
        {
            using other = CppHeapWrapper<Z>;
        };

        T *address(T &val) const noexcept
        {
            return std::addressof(val);
        }

        const T *address(const T &val) const noexcept
        {
            return std::addressof(val);
        }
    #endif

        inline CppHeapWrapper(std::shared_ptr<Heap> pHeap) :
            pHeap(pHeap)
        { }

        AU_COPY_MOVE_DEF(CppHeapWrapper)

        std::shared_ptr<Heap> pHeap;

        constexpr void deallocate(const T *pType,
                                  const size_t count)
        {
            this->pHeap->Free((T *)pType);
        }

        constexpr AU_ALLOC T *allocate(const size_t count)
        {
            if (!count)
            {
                return nullptr;
            }
            
            auto pData = this->pHeap->FAlloc(count, alignof(T));
            if (!pData)
            {
                throw std::bad_alloc();
            }
            return (T *)pData;
        }

    #if defined(AU_LANG_CPP_23)
        constexpr std::allocation_result<T *> allocate_at_least(const size_t count)
        {
            auto pThat = this->allocate(count);
            return { pThat, this->pHeap->GetChunkSize(pThat) };
        }
    #endif
    };
}