/**
 * @file thread_pool.hpp
 * @brief thread pool
 * @author DeepRobotics
 * @version 1.0
 * @date 2026-01-07
 *
 * @copyright Copyright (c) 2025  DeepRobotics
 *
 */
#pragma once
#include <atomic>
#include <condition_variable>
#include <functional>
#include <mutex>
#include <queue>
#include <thread>
#include <vector>

class ThreadPool {
public:
    ThreadPool(size_t numThreads) : stop(false) {
        for (size_t i = 0; i < numThreads; ++i) {
            workers.emplace_back([this]() {
                while (true) {
                    std::function<void()> task;
                    {
                        std::unique_lock<std::mutex> lock(this->queueMutex);
                        this->condition.wait(lock, [this] { return this->stop || !this->tasks.empty(); });
                        if (this->stop && this->tasks.empty()) return;
                        task = std::move(this->tasks.front());
                        this->tasks.pop();
                    }
                    task();
                }
            });
        }
    }

    ~ThreadPool() {
        {
            std::unique_lock<std::mutex> lock(queueMutex);
            stop = true;
        }
        condition.notify_all();
        for (std::thread& worker : workers) worker.join();
    }

    void enqueue(std::function<void()> task) {
        {
            std::unique_lock<std::mutex> lock(queueMutex);
            tasks.emplace(task);
        }
        condition.notify_one();
    }

private:
    std::vector<std::thread> workers;
    std::queue<std::function<void()>> tasks;

    std::mutex queueMutex;
    std::condition_variable condition;
    std::atomic<bool> stop;
};