// SPDX-FileCopyrightText: Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
// SPDX-License-Identifier: GPL-3.0-or-later

#include "cares_init.hh"

#include <ares.h>

#include <string>
#include <system_error>

using namespace std::literals;

auto malcontent::CAresLibrary::instance() -> std::shared_ptr<CAresLibrary> {
    if (auto ret = _instance.lock()) {
        return ret;
    }

    auto ret = std::make_shared<CAresLibrary>(Private{});
    _instance = ret;
    return ret;
}

malcontent::CAresLibrary::CAresLibrary(Private) {
    std::lock_guard guard { _init_mutex };
    int ret = ares_library_init(ARES_LIB_INIT_ALL);
    if (ret != ARES_SUCCESS) {
        const auto err = "ares_library_init: "s + ares_strerror(ret);
        throw std::system_error(ret, std::generic_category(), err.c_str());
    }
}

malcontent::CAresLibrary::~CAresLibrary() noexcept {
    std::lock_guard guard { _init_mutex };
    ares_library_cleanup();
}

std::mutex malcontent::CAresLibrary::_init_mutex{};

std::weak_ptr<malcontent::CAresLibrary> malcontent::CAresLibrary::_instance{};