#pragma once

#include "utility.h"
#include <Entities/Entity.h>

class EntityView
{
public:
	friend class EntityManager;
	EntityView() = delete;
	EntityView(EntityIndex, EntityIndex);


	class iterator
	{
	public:
		iterator(EntityIndex);
		iterator& operator++();
		iterator operator++(int);
		iterator& operator--();
		iterator operator--(int);
		Entity operator*();
		Entity operator[](int);
		bool operator==(iterator);
		bool operator!=(iterator);
	private:
		EntityIndex m_currentEntity;
	};

	class const_iterator
	{
	public:
		const_iterator(EntityIndex index);
		const_iterator& operator++();
		const_iterator operator++(int);
		const_iterator& operator--();
		const_iterator operator--(int);
		const Entity operator*();
		const Entity operator[](int index);
		bool operator==(const_iterator);
		bool operator!=(const_iterator);
	private:
		EntityIndex m_currentEntity;
	};

	Entity operator[](EntityIndex) const;

	iterator begin() { return iterator(m_start); }
	iterator end()   { return iterator(m_start + m_size); }

	const_iterator cbegin() const { return const_iterator(m_start); }
	const_iterator cend()   const { return const_iterator(m_start + m_size); }
private:
	EntityIndex m_start;
	EntityIndex m_size;
};