EnumSet.h

#pragma once
 
#include "mc/_HeaderOutputPredefine.h"
#include "mc/platform/brstd/bitset.h"
 
namespace Bedrock {
 
template <typename TEnum, auto SizeEnum>
class EnumSet {
public:
    using size_type                    = size_t;
    static constexpr size_type MaxSize = static_cast<size_type>(SizeEnum);
    using mContainertype               = brstd::bitset<MaxSize, std::underlying_type_t<TEnum>>;
    using value_type                   = TEnum;
 
    mContainertype mContainer;
 
    class iterator {
        using reference = TEnum;
 
    public:
        friend class EnumSet;
        iterator(EnumSet const& set, size_type index) : set_(&set), index_(index) {}
        EnumSet const* set_;
        size_type      index_;
    };
    static_assert(sizeof(iterator) == 16);
 
    using const_iterator = iterator;
 
    constexpr std::pair<iterator, bool> insert(value_type value) {
        using U  = std::underlying_type_t<TEnum>;
        auto idx = static_cast<U>(value);
        if (mContainer.test(idx)) {
            return {iterator(*this, idx), false};
        }
        mContainer.set(idx);
        return {iterator(*this, idx), true};
    }
 
    constexpr bool contains(value_type const value) const {
        using U = std::underlying_type_t<TEnum>;
        return mContainer.test(static_cast<U>(value));
    }
};
 
} // namespace Bedrock