EventDispatcher.h

Go to the documentation of this file.

#pragma once

 
#include <quasar/events/Event.h>
 
#include <concepts>
#include <functional>
#include <utility>
 
namespace Quasar
{
    template <typename T>
    concept EventClass = std::derived_from<T, Event> && requires {
        { T::GetStaticType() } -> std::same_as<EventType>;
    };

    class EventDispatcher
    {
    public:
        explicit EventDispatcher(Event& event) : m_Event(event) {}

        template <EventClass T, std::predicate<T&> Handler>
        bool Dispatch(Handler&& handler)
        {
            if (m_Event.GetType() != T::GetStaticType())
            {
                return false;
            }
 
            if (std::invoke(std::forward<Handler>(handler), static_cast<T&>(m_Event)))
            {
                m_Event.SetHandled(true);
            }
            return true;
        }
 
    private:
        // The dispatcher only lives while one event is dispatched, so it can keep a reference to it
        // NOLINTNEXTLINE(cppcoreguidelines-avoid-const-or-ref-data-members)
        Event& m_Event;
    };
}