ComponentView.h

// Copyright(c) 2019 - 2020, #Momo
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#pragma once

#include "Utilities/AbstractFactory/AbstractFactory.h"
#include "Utilities/VectorPool/VectorPool.h"

namespace MxEngine
{
    template<typename T>
    class ComponentView
    {
    public:
        using Pool = VectorPool<ManagedResource<T>>;

        class ComponentIterator
        {
        public:
            using PoolIterator = typename Pool::PoolIterator;
        private:
            PoolIterator it;
        public:
            ComponentIterator(PoolIterator it) : it(it) {}

            ComponentIterator operator++(int)
            {
                ComponentIterator copy = *this;
                it++;
                return copy;
            }

            ComponentIterator operator++()
            {
                ++it;
                return *this;
            }

            ComponentIterator operator--(int)
            {
                ComponentIterator copy = *this;
                it--;
                return copy;
            }

            ComponentIterator operator--()
            {
                --it;
                return *this;
            }

            T* operator->()
            {
                return &it->value;
            }

            const T* operator->() const
            {
                return &it->value;
            }

            T& operator*()
            {
                return it->value;
            }

            const T& operator*() const
            {
                return it->value;
            }

            bool operator==(const ComponentIterator& other) const
            {
                return it == other.it;
            }

            bool operator!=(const ComponentIterator& other) const
            {
                return it != other.it;
            }
        };
    private:
        Pool& ref;
    public:
        explicit ComponentView(Pool& ref) : ref(ref) {}

        ComponentIterator begin()
        {
            return ComponentIterator{ ref.begin() };
        }

        const ComponentIterator begin() const
        {
            return ComponentIterator{ ref.begin() };
        }

        ComponentIterator end()
        {
            return ComponentIterator{ ref.end() };
        }

        const ComponentIterator end() const
        {
            return ComponentIterator{ ref.end() };
        }
    };
}