/*****************************************************************************************
 *                                                                                       *
 * OpenSpace                                                                             *
 *                                                                                       *
 * Copyright (c) 2014-2022                                                               *
 *                                                                                       *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this  *
 * software and associated documentation files (the "Software"), to deal in the Software *
 * without restriction, including without limitation the rights to use, copy, modify,    *
 * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to    *
 * permit persons to whom the Software is furnished to do so, subject to the following   *
 * conditions:                                                                           *
 *                                                                                       *
 * The above copyright notice and this permission notice shall be included in all copies *
 * or substantial portions of the Software.                                              *
 *                                                                                       *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,   *
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A         *
 * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT    *
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF  *
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE  *
 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                                         *
 ****************************************************************************************/

namespace openspace {

template <typename T>
T InterruptibleConcurrentQueue<T>::pop() {
    auto isInterruptedOrNotEmpty = [this]() {
        if (_interrupted) return true;
        return !_queue.empty();
    };

    std::unique_lock lock(_mutex);

    // Block execution until interrupted or queue not empty
    if (!isInterruptedOrNotEmpty()) {
        _notifyForPop.wait(lock, isInterruptedOrNotEmpty);
    }

    if (_interrupted) throw ghoul::RuntimeError{""};

    auto item = _queue.front();
    _queue.pop();

    return item;
}

template <typename T>
void InterruptibleConcurrentQueue<T>::interrupt() {
    _interrupted = true;
    _notifyForPop.notify_all();
}

template <typename T>
void InterruptibleConcurrentQueue<T>::push(const T& item) {
    if (_interrupted) return;
    std::unique_lock<std::mutex> mlock(_mutex);
    _queue.push(item);
    mlock.unlock();
    _notifyForPop.notify_one();
}

template <typename T>
void InterruptibleConcurrentQueue<T>::push(T&& item) {
    if (_interrupted) return;
    std::unique_lock<std::mutex> mlock(_mutex);
    _queue.push(std::move(item));
    mlock.unlock();
    _notifyForPop.notify_one();
}

} // namespace openspace