Enum.hpp

Go to the documentation of this file.

//
//  CeresEngine - A game development framework
//
//  Created by Rogiel Sulzbach.
//  Copyright (c) 2018-2022 Rogiel Sulzbach. All rights reserved.
//
 
#pragma once
 
#include "Box.hpp"
#include "MetaContainer.hpp"
#include "MetaItem.hpp"
#include "Type.hpp"
 
#include "CeresEngine/Foundation/Function.hpp"
#include "CeresEngine/Foundation/Container/Optional.hpp"
 
#include <functional>
 
namespace CeresEngine {
 
    class EnumValue;
 
    class Enum : public MetaContainer {
    public:
        using ValueGetter = UniqueFunction<Box() const>;
 
    public:
        String name;
 
    public:
        explicit Enum(const StringView name) : name(name) {}
 
    public:
        using EnumerateElementFunction = FunctionView<bool(const EnumValue&) const>;
 
    public:
        [[nodiscard]] const EnumValue* getEnumValueWithName(StringView name) const;
 
        [[nodiscard]] const EnumValue* getEnumValueWithValue(const Box& name) const;
 
        [[nodiscard]] Optional<const Box&> getValue(StringView name) const;
 
        [[nodiscard]] Optional<StringView> getName(const Box& value) const;
 
        void forEachValue(const EnumerateElementFunction& func) const;
 
        [[nodiscard]] Generator<const EnumValue> forEachValue() const;
 
    protected:
        void addElement(StringView name, ValueGetter&& value);
    };
 
    class EnumValue : public MetaItem {
    public:
        using ValueGetter = typename Enum::ValueGetter;
 
    public:
        StringView name;
 
    private:
        ValueGetter mValueGetter;
 
        mutable Box mValue;
 
        mutable Box mValueReference;
 
    public:
        explicit EnumValue(Enum& owner, StringView name, ValueGetter&& getter);
 
    public:
        static constexpr MetaCategory kCategory = MetaCategory::EnumValue;
 
        [[nodiscard]] MetaCategory getCategory() const override { return kCategory; }
 
    public:
        [[nodiscard]] const Box& getValue() const noexcept {
            if(!mValue) {
                CE_ASSERT(mValueGetter != nullptr);
                mValue = mValueGetter();
                mValueReference = mValue.cref();
            }
            return mValueReference;
        }
    };
 
} // namespace CeresEngine