Synnefo » Pithos MS Client

// -----------------------------------------------------------------------

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

// Copyright 2011 GRNET S.A. All rights reserved.

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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();

            });

        }

    }

}