/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Copyright 2018 Danny Robson <danny@nerdcruft.net>
 */

#ifndef CRUFT_UTIL_THREAD_MONITOR_HPP
#define CRUFT_UTIL_THREAD_MONITOR_HPP

#include <mutex>
#include <utility>
#include <functional>


namespace util::thread {
    template <typename ValueT, typename MutexT = std::mutex>
    class monitor {
    public:
        template <typename ...Args>
        monitor (Args &&...args):
            m_value (std::forward<Args> (args)...)
        { ; }

        class proxy {
        public:
            proxy (MutexT &_mutex, ValueT &_value):
                m_guard (_mutex),
                m_value (_value)
            { ; }

            ValueT* operator-> ()
            {
                return &m_value;
            }

        private:
            std::lock_guard<MutexT> m_guard;
            ValueT &m_value;
        };

        auto acquire (void) { return proxy (m_mutex, m_value); }
        auto operator-> () { return acquire (); }

    private:
        MutexT m_mutex;
        ValueT m_value;
    };
};

#endif