#include "is_prime.h"
#include <cmath>
#include <algorithm>
#include <thread>
#include <atomic>
#include <vector>
#include <iostream>

void CheckFunc(uint64_t x, std::atomic<uint64_t>& i, std::atomic<bool>& result) {
    result.store(x % i != 0);
    i.fetch_add(1);
}

void CloseAllThreads(std::vector<std::thread>& threads) {
    for (auto& this_thread : threads) {
        if (this_thread.joinable()) {
            this_thread.join();
        }
    }
}

bool IsPrime(uint64_t x) {
    if (x <= 1) {
        return false;
    }
    uint64_t root = sqrt(x);
    auto bound = std::min(root + 6, x);
    std::atomic<uint64_t> i = 2ull;
    std::atomic<bool> result = true;
    std::vector<std::thread> threads(10);

    while (i.load() < bound && result.load()) {
        for (auto &this_thread : threads) {
            if (i.load() < bound) {
                this_thread = std::thread(CheckFunc, x, std::ref(i), std::ref(result));
            } else {
                break;
            }
            if (!result.load()) {
                CloseAllThreads(threads);
                break;
            }
        }
    }

    CloseAllThreads(threads);
    std::cout << x << " - " << i.load() << "... " << result.load() << std::endl;
    return result;
}