Synnefo » Pithos MS Client

#region

/* -----------------------------------------------------------------------

 * <copyright file="JobQueue.cs" company="GRNet">

 * 

 * Copyright 2011-2012 GRNET S.A. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or

 * without modification, are permitted provided that the following

 * conditions are met:

 *

 *   1. Redistributions of source code must retain the above

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 *      disclaimer.

 *

 *   2. Redistributions in binary form must reproduce the above

 *      copyright notice, this list of conditions and the following

 *      disclaimer in the documentation and/or other materials

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 *

 * THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

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#endregion

using System.Collections.Concurrent;

using System.Threading;

using System.Threading.Tasks;

namespace Pithos.Core

{

    using System;

    using System.Collections.Generic;

    using System.Linq;

    using System.Text;

    /// <summary>

    /// TODO: Update summary.

    /// </summary>

    public class JobQueue

    {

        private readonly BlockingCollection<Action> _statusUpdateQueue = new BlockingCollection<Action>();

        private CancellationToken _cancellationToken;

        public void Start(CancellationToken token)

        {

            _cancellationToken = token;

            Task.Factory.StartNew(ProcessUpdates, _cancellationToken);

        }

        private void ProcessUpdates()

        {

            foreach (var action in _statusUpdateQueue.GetConsumingEnumerable())

            {

                action();

            }

        }

        public void Add(Action action)

        {

            _statusUpdateQueue.Add(action);

        }

        public void Stop()

        {

            _statusUpdateQueue.CompleteAdding();

        }

    }   

    public class JobAgent:Agent<Action>

    {

        protected JobAgent(Action<Agent<Action>>  action)

            :base(action)

        {

        }

        public static JobAgent Create()

        {

            return (JobAgent)Start(queue =>

            {

                Action loop = null;

                loop = () =>

                {

                    var job = queue.Receive();

                    job.ContinueWith(t =>

                    {

                        t.IgnoreExceptions();

                        var action = job.Result;

                        action();

                        queue.DoAsync(loop);

                    });

                };

                loop();

            });

        }

    }

}