/*//////////////////////////////////////////////////////////////////////////////
Copyright (c) 2013 Jamboree

Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//////////////////////////////////////////////////////////////////////////////*/
#ifndef BOOST_ASIO_CONDITION_VARIABLE_HPP_INCLUDED
#define BOOST_ASIO_CONDITION_VARIABLE_HPP_INCLUDED


#include <deque>
#include <boost/asio/io_service.hpp>
#include <boost/asio/spawn.hpp>


namespace boost { namespace asio
{
    class condition_variable
    {
        struct handler_t
        {
            explicit handler_t(yield_context const& ctx)
              : coro_(ctx.coro_.lock())
            {}

            void operator()()
            {
                (*coro_)();
            }

            detail::shared_ptr<yield_context::callee_type> coro_;
        };

    public:
        
        explicit condition_variable(io_service& io)
          : _io(io)
        {}

        void wait(yield_context const& ctx)
        {
            _suspended.push_back(handler_t(ctx));
            ctx.ca_();
        }

        void notify_one()
        {
            if (_suspended.empty())
                return;
            _io.post(_suspended.front());
            _suspended.pop_front();
        }

        void notify_all()
        {
            for (handler_t& h : _suspended)
                _io.post(h);
            _suspended.clear();
        }

    private:
        
        io_service& _io;
        std::deque<handler_t> _suspended;
    };

    struct condition_flag
    {
        explicit condition_flag(io_service& io)
          : _b(), _cond(io)
        {}

        void wait(yield_context const& ctx)
        {
            while (!_b)
                _cond.wait(ctx);
        }

        condition_flag& operator=(bool b)
        {
            if (_b = b)
                _cond.notify_all();
        }

    private:

        bool _b;
        condition_variable _cond;
    };
}}


#endif