#pragma once

#include <atomic>

namespace fluidsim::port {

class ThreadLoadTracker {
public:
    void record(double busy_milliseconds, double budget_milliseconds) {
        if (budget_milliseconds <= 0.0) return;
        constexpr double alpha = 0.05;
        const double instant = busy_milliseconds / budget_milliseconds * 100.0;
        const double previous = load_percent_.load(std::memory_order_relaxed);
        load_percent_.store(previous + alpha * (instant - previous), std::memory_order_relaxed);
        last_busy_ms_.store(busy_milliseconds, std::memory_order_relaxed);
    }
    double load_percent() const { return load_percent_.load(std::memory_order_relaxed); }
    double last_step_microseconds() const { return last_busy_ms_.load(std::memory_order_relaxed) * 1000.0; }
private:
    std::atomic<double> load_percent_{};
    std::atomic<double> last_busy_ms_{};
};

} // namespace fluidsim::port