View.hpp

#pragma once
#include <tuple>
#include "Types.hpp"
#include "Registry.hpp"
 
namespace vex {

 
template<typename... Components>
class View {
private:
    Registry& m_registry;
 
public:
    View(Registry& reg) : m_registry(reg) {}

    template<typename Func>
    void each(Func func) {
        using FirstT = typename std::tuple_element<0, std::tuple<Components...>>::type;
 
        auto* leadArray = m_registry.try_get_storage_internal<FirstT>();
        if (!leadArray) return;
 
        auto& entities = leadArray->get_entities();
 
        for (ptrdiff_t i = static_cast<ptrdiff_t>(entities.size()) - 1; i >= 0; --i) {
 
            if (i >= static_cast<ptrdiff_t>(entities.size())) continue;
 
            Entity e = entities[i];
 
            if ((m_registry.has<Components>(e) && ...)) {
                func(e, m_registry.get<Components>(e)...);
            }
        }
    }
};
 
}