EventDispatcher.hpp

Go to the documentation of this file.

/**********************************************************************************/
/* This file is part of Berserk Engine project                                    */
/* https://github.com/EgorOrachyov/Berserk                                        */
/**********************************************************************************/
/* MIT License                                                                    */
/*                                                                                */
/* Copyright (c) 2018 - 2021 Egor Orachyov                                        */
/*                                                                                */
/* Permission is hereby granted, free of charge, to any person obtaining a copy   */
/* of this software and associated documentation files (the "Software"), to deal  */
/* in the Software without restriction, including without limitation the rights   */
/* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell      */
/* copies of the Software, and to permit persons to whom the Software is          */
/* furnished to do so, subject to the following conditions:                       */
/*                                                                                */
/* The above copyright notice and this permission notice shall be included in all */
/* copies or substantial portions of the Software.                                */
/*                                                                                */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR     */
/* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,       */
/* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE    */
/* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER         */
/* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,  */
/* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE  */
/* SOFTWARE.                                                                      */
/**********************************************************************************/
 
#ifndef BERSERK_EVENTDISPATCHER_HPP
#define BERSERK_EVENTDISPATCHER_HPP
 
#include <core/Config.hpp>
#include <core/Typedefs.hpp>
#include <core/event/Event.hpp>
 
#include <functional>
#include <unordered_map>
#include <vector>
 
BRK_NS_BEGIN
 
class EventDispatcher final {
public:
    using ListenerFunc = std::function<bool(const Event &)>;
    using Handle = size_t;
 
    BRK_API void Dispatch(const Ref<Event> &event);
 
    BRK_API Handle Subscribe(const EventType &eventType, ListenerFunc func, bool paused = false);
 
    BRK_API void Unsubscribe(Handle handle);
 
    BRK_API void Pause(Handle handle);
 
    BRK_API void Resume(Handle handle);
 
private:
    friend class Engine;
 
    struct Listener {
        ListenerFunc callback;
        Handle handle;
        bool paused = false;
    };
 
    void Update();
    Handle GetNext();
 
private:
    std::unordered_map<EventType, std::vector<Listener>> mListeners;
    std::unordered_map<Handle, EventType> mListenersTypes;
 
    std::vector<Listener> mPendingAdd;
    std::vector<Handle> mPendingRemove;
    std::vector<std::pair<Handle, bool>> mPendingPause;
 
    std::vector<Ref<Event>> mQueuedEvents;
    std::vector<Ref<Event>> mQueuedEventsExec;
 
    Handle mNextHandle = 0;
};
 
BRK_NS_END
 
 
#endif//BERSERK_EVENTDISPATCHER_HPP