PeriodicTrigger.h

//
//  PeriodicTrigger.h
//  avara3d
//
//  Created by Morgan Davis on 8/4/26.
//  Copyright © 2026 Morgan K Davis. All rights reserved.
//
 
#ifndef AVARA3D_UTIL_PERIODICTRIGGER_H
#define AVARA3D_UTIL_PERIODICTRIGGER_H
 
#include <chrono>
#include <cstddef>
#include <functional>
#include <optional>
 
namespace a3d::util {
 
    class PeriodicTrigger {
 
    public:
        // [Public Lifecycle Functions]
 
        explicit PeriodicTrigger(std::chrono::duration<double> interval, bool deferFirstFire = false);
 
        // [Public Member Functions]
 
        template<typename Function>
        std::size_t update(double time, Function&& function) {
 
            const auto count = dueCount(time);
 
            for (std::size_t i = 0; i < count; ++i) {
                std::invoke(function);
            }
 
            return count;
        }
 
        void reset() noexcept;
 
    private:
        // [Private Member Functions]
 
        std::size_t           dueCount(double time);
 
        // [Private Member Variables]
 
        double                _interval;
        bool                  _deferFirstFire;
        std::optional<double> _nextFireTime;
        std::optional<double> _lastTime;
    };
 
}
 
#endif // AVARA3D_UTIL_PERIODICTRIGGER_H