Synnefo » Pithos MS Client

#region

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

 * <copyright file="ShellViewModel.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

 *      copyright notice, this list of conditions and the following

 *      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

 *      provided with the distribution.

 *

 *

 * 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

 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN

 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 *

 * The views and conclusions contained in the software and

 * documentation are those of the authors and should not be

 * interpreted as representing official policies, either expressed

 * or implied, of GRNET S.A.

 * </copyright>

 * -----------------------------------------------------------------------

 */

#endregion

using System.Collections.Concurrent;

using System.Diagnostics;

using System.Diagnostics.Contracts;

using System.IO;

using System.Net;

using System.Reflection;

using System.Runtime.InteropServices;

using System.ServiceModel;

using System.Threading.Tasks;

using System.Windows;

using System.Windows.Controls.Primitives;

using AppLimit.NetSparkle;

using Caliburn.Micro;

using Hardcodet.Wpf.TaskbarNotification;

using Pithos.Client.WPF.Configuration;

using Pithos.Client.WPF.FileProperties;

using Pithos.Client.WPF.Preferences;

using Pithos.Client.WPF.SelectiveSynch;

using Pithos.Client.WPF.Services;

using Pithos.Client.WPF.Shell;

using Pithos.Core;

using Pithos.Core.Agents;

using Pithos.Interfaces;

using System;

using System.Collections.Generic;

using System.Linq;

using Pithos.Network;

using StatusService = Pithos.Client.WPF.Services.StatusService;

namespace Pithos.Client.WPF {

	using System.ComponentModel.Composition;

	///<summary>

	/// The "shell" of the Pithos application displays the taskbar  icon, menu and notifications.

	/// The shell also hosts the status service called by shell extensions to retrieve file info

	///</summary>

	///<remarks>

	/// It is a strange "shell" as its main visible element is an icon instead of a window

	/// The shell subscribes to the following events:

	/// * Notification:  Raised by components that want to notify the user. Usually displayed in a balloon

	/// * SelectiveSynchChanges: Notifies that the user made changes to the selective synch folders for an account. Raised by the Selective Synch dialog. Located here because the monitors are here

	/// * ShowFilePropertiesEvent: Raised when a shell command requests the display of the file/container properties dialog

	///</remarks>		

	//TODO: CODE SMELL Why does the shell handle the SelectiveSynchChanges?

	[Export(typeof(IShell))]

	public class ShellViewModel : Screen, IStatusNotification, IShell,

		IHandle<Notification>, IHandle<SelectiveSynchChanges>, IHandle<ShowFilePropertiesEvent>

	{

		//The Status Checker provides the current synch state

		//TODO: Could we remove the status checker and use events in its place?

		private readonly IStatusChecker _statusChecker;

		private readonly IEventAggregator _events;

		public PithosSettings Settings { get; private set; }

		private readonly ConcurrentDictionary<string, PithosMonitor> _monitors = new ConcurrentDictionary<string, PithosMonitor>();

		///<summary>

		/// Dictionary of account monitors, keyed by account

		///</summary>

		///<remarks>

		/// One monitor class is created for each account. The Shell needs access to the monitors to execute start/stop/pause commands,

		/// retrieve account and boject info		

		///</remarks>

		// TODO: Does the Shell REALLY need access to the monitors? Could we achieve the same results with a better design?

		// TODO: The monitors should be internal to Pithos.Core, even though exposing them makes coding of the Object and Container windows easier

		public ConcurrentDictionary<string, PithosMonitor> Monitors

		{

			get { return _monitors; }

		}

		///<summary>

		/// The status service is used by Shell extensions to retrieve file status information

		///</summary>

		//TODO: CODE SMELL! This is the shell! While hosting in the shell makes executing start/stop commands easier, it is still a smell

		private ServiceHost _statusService;

		//Logging in the Pithos client is provided by log4net

        private static readonly log4net.ILog Log = log4net.LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

		//Lazily initialized File Version info. This is done once and lazily to avoid blocking the UI

		private readonly Lazy<FileVersionInfo> _fileVersion;

	    private readonly PollAgent _pollAgent;

		///<summary>

		/// The Shell depends on MEF to provide implementations for windowManager, events, the status checker service and the settings

		///</summary>

		///<remarks>

		/// The PithosSettings class encapsulates the app's settings to abstract their storage mechanism (App settings, a database or registry)

		///</remarks>

		[ImportingConstructor]		

		public ShellViewModel(IWindowManager windowManager, IEventAggregator events, IStatusChecker statusChecker, PithosSettings settings,PollAgent pollAgent)

		{

			try

			{

				_windowManager = windowManager;

				//CHECK: Caliburn doesn't need explicit command construction

				//OpenPithosFolderCommand = new PithosCommand(OpenPithosFolder);

				_statusChecker = statusChecker;

				//The event subst

				_events = events;

				_events.Subscribe(this);

			    _pollAgent = pollAgent;

				Settings = settings;

				Proxy.SetFromSettings(settings);

				StatusMessage = "In Synch";

				_fileVersion=  new Lazy<FileVersionInfo>(() =>

				{

					Assembly assembly = Assembly.GetExecutingAssembly();

					var fileVersion = FileVersionInfo.GetVersionInfo(assembly.Location);

					return fileVersion;

				});

				_accounts.CollectionChanged += (sender, e) =>

												   {

													   NotifyOfPropertyChange(() => OpenFolderCaption);

													   NotifyOfPropertyChange(() => HasAccounts);

												   };

			}

			catch (Exception exc)

			{

				Log.Error("Error while starting the ShellViewModel",exc);

				throw;

			}

		}

		protected override void OnActivate()

		{

			base.OnActivate();

            _sparkle = new Sparkle(Settings.UpdateUrl);

            _sparkle.updateDetected += OnUpgradeDetected;

            _sparkle.ShowDiagnosticWindow = Settings.UpdateDiagnostics;

            //Must delay opening the upgrade window

            //to avoid Windows Messages sent by the TaskbarIcon

            TaskEx.Delay(5000).ContinueWith(_=>

                Execute.OnUIThread(()=> _sparkle.StartLoop(true,Settings.UpdateForceCheck,Settings.UpdateCheckInterval)));

			StartMonitoring();                    

		}

	    private void OnUpgradeDetected(object sender, UpdateDetectedEventArgs e)

	    {

	        Log.InfoFormat("Update detected {0}",e.LatestVersion);

	    }

        public void CheckForUpgrade()

        {

            _sparkle.StopLoop();

            _sparkle.Dispose();

            _sparkle=new Sparkle(Settings.UpdateUrl);

            _sparkle.StartLoop(true,true,Settings.UpdateCheckInterval);

        }

	    private async void StartMonitoring()

		{

			try

			{

				var accounts = Settings.Accounts.Select(MonitorAccount);

				await TaskEx.WhenAll(accounts);

				_statusService = StatusService.Start();

/*

				foreach (var account in Settings.Accounts)

				{

					await MonitorAccount(account);

				}

*/

			}

			catch (AggregateException exc)

			{

				exc.Handle(e =>

				{

					Log.Error("Error while starting monitoring", e);

					return true;

				});

				throw;

			}

		}

		protected override void OnDeactivate(bool close)

		{

			base.OnDeactivate(close);

			if (close)

			{

				StatusService.Stop(_statusService);

				_statusService = null;

			}

		}

		public Task MonitorAccount(AccountSettings account)

		{

			return Task.Factory.StartNew(() =>

			{                                                

				PithosMonitor monitor;

				var accountName = account.AccountName;

				if (_monitors.TryGetValue(accountName, out monitor))

				{

					//If the account is active

                    if (account.IsActive)

                    {

                        //The Api Key may have changed throuth the Preferences dialog

                        monitor.ApiKey = account.ApiKey;

						Debug.Assert(monitor.StatusNotification == this,"An existing monitor should already have a StatusNotification service object");

                        monitor.RootPath = account.RootPath;

                        //Start the monitor. It's OK to start an already started monitor,

                        //it will just ignore the call                        

                        StartMonitor(monitor).Wait();

                    }

                    else

                    {

                        //If the account is inactive

                        //Stop and remove the monitor

                        RemoveMonitor(accountName);

                    }

					return;

				}

				//Create a new monitor/ Can't use MEF here, it would return a single instance for all monitors

				monitor = new PithosMonitor

							  {

								  UserName = accountName,

								  ApiKey = account.ApiKey,                                  

								  StatusNotification = this,

								  RootPath = account.RootPath

							  };

				//PithosMonitor uses MEF so we need to resolve it

				IoC.BuildUp(monitor);

				monitor.AuthenticationUrl = account.ServerUrl;

				_monitors[accountName] = monitor;

				if (account.IsActive)

				{

					//Don't start a monitor if it doesn't have an account and ApiKey

					if (String.IsNullOrWhiteSpace(monitor.UserName) ||

						String.IsNullOrWhiteSpace(monitor.ApiKey))

						return;

					StartMonitor(monitor);

				}

			});

		}

		protected override void OnViewLoaded(object view)

		{

			UpdateStatus();

			var window = (Window)view;            

			TaskEx.Delay(1000).ContinueWith(t => Execute.OnUIThread(window.Hide));

			base.OnViewLoaded(view);

		}

		#region Status Properties

		private string _statusMessage;

		public string StatusMessage

		{

			get { return _statusMessage; }

			set

			{

				_statusMessage = value;

				NotifyOfPropertyChange(() => StatusMessage);

			}

		}

		private readonly ObservableConcurrentCollection<AccountInfo> _accounts = new ObservableConcurrentCollection<AccountInfo>();

		public ObservableConcurrentCollection<AccountInfo> Accounts

		{

			get { return _accounts; }

		}

		public bool HasAccounts

		{

			get { return _accounts.Count > 0; }

		}

		public string OpenFolderCaption

		{

			get

			{

				return (_accounts.Count == 0)

						? "No Accounts Defined"

						: "Open Pithos Folder";

			}

		}

		private string _pauseSyncCaption="Pause Synching";

		public string PauseSyncCaption

		{

			get { return _pauseSyncCaption; }

			set

			{

				_pauseSyncCaption = value;

				NotifyOfPropertyChange(() => PauseSyncCaption);

			}

		}

		private readonly ObservableConcurrentCollection<FileEntry> _recentFiles = new ObservableConcurrentCollection<FileEntry>();

		public ObservableConcurrentCollection<FileEntry> RecentFiles

		{

			get { return _recentFiles; }

		}

		private string _statusIcon="../Images/Pithos.ico";

		public string StatusIcon

		{

			get { return _statusIcon; }

			set

			{

				//TODO: Ensure all status icons use the Pithos logo

				_statusIcon = value;

				NotifyOfPropertyChange(() => StatusIcon);

			}

		}

		#endregion

		#region Commands

        public void ShowPreferences()

        {

            ShowPreferences(null);

        }

		public void ShowPreferences(string currentTab)

		{

			//Settings.Reload();

		    var preferences = new PreferencesViewModel(_windowManager, _events, this, Settings,currentTab);

		    _windowManager.ShowDialog(preferences);

		}

		public void AboutPithos()

		{

			var about = new AboutViewModel();

			_windowManager.ShowWindow(about);

		}

		public void SendFeedback()

		{

			var feedBack =  IoC.Get<FeedbackViewModel>();

			_windowManager.ShowWindow(feedBack);

		}

		//public PithosCommand OpenPithosFolderCommand { get; private set; }

		public void OpenPithosFolder()

		{

			var account = Settings.Accounts.FirstOrDefault(acc => acc.IsActive);

			if (account == null)

				return;

			Process.Start(account.RootPath);

		}

		public void OpenPithosFolder(AccountInfo account)

		{

			Process.Start(account.AccountPath);

		}

/*

		public void GoToSite()

		{            

			var site = Properties.Settings.Default.PithosSite;

			Process.Start(site);            

		}

*/

		public void GoToSite(AccountInfo account)

		{

		    var uri = account.SiteUri.Replace("http://","https://");            

		    Process.Start(uri);

		}

	    /// <summary>

        /// Open an explorer window to the target path's directory

        /// and select the file

        /// </summary>

        /// <param name="entry"></param>

        public void GoToFile(FileEntry entry)

        {

            var fullPath = entry.FullPath;

            if (!File.Exists(fullPath) && !Directory.Exists(fullPath))

                return;

            Process.Start("explorer.exe","/select, " + fullPath);

        }

        public void OpenLogPath()

        {

            var appDataPath = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);

            var pithosDataPath = Path.Combine(appDataPath, "GRNET");

            Process.Start(pithosDataPath);

        }

        public void ShowFileProperties()

		{

			var account = Settings.Accounts.First(acc => acc.IsActive);            

			var dir = new DirectoryInfo(account.RootPath + @"\pithos");

			var files=dir.GetFiles();

			var r=new Random();

			var idx=r.Next(0, files.Length);

			ShowFileProperties(files[idx].FullName);            

		}

		public void ShowFileProperties(string filePath)

		{

			if (String.IsNullOrWhiteSpace(filePath))

				throw new ArgumentNullException("filePath");

			if (!File.Exists(filePath) && !Directory.Exists(filePath))

				throw new ArgumentException(String.Format("Non existent file {0}",filePath),"filePath");

			Contract.EndContractBlock();

			var pair=(from monitor in  Monitors

							   where filePath.StartsWith(monitor.Value.RootPath, StringComparison.InvariantCultureIgnoreCase)

								   select monitor).FirstOrDefault();

			var accountMonitor = pair.Value;

			if (accountMonitor == null)

				return;

			var infoTask=Task.Factory.StartNew(()=>accountMonitor.GetObjectInfo(filePath));

			var fileProperties = new FilePropertiesViewModel(this, infoTask,filePath);

			_windowManager.ShowWindow(fileProperties);

		} 

		public void ShowContainerProperties()

		{

			var account = Settings.Accounts.First(acc => acc.IsActive);            

			var dir = new DirectoryInfo(account.RootPath);

			var fullName = (from folder in dir.EnumerateDirectories()

							where (folder.Attributes & FileAttributes.Hidden) == 0

							select folder.FullName).First();

			ShowContainerProperties(fullName);            

		}

		public void ShowContainerProperties(string filePath)

		{

			if (String.IsNullOrWhiteSpace(filePath))

				throw new ArgumentNullException("filePath");

			if (!Directory.Exists(filePath))

				throw new ArgumentException(String.Format("Non existent file {0}",filePath),"filePath");

			Contract.EndContractBlock();

			var pair=(from monitor in  Monitors

							   where filePath.StartsWith(monitor.Value.RootPath, StringComparison.InvariantCultureIgnoreCase)

								   select monitor).FirstOrDefault();

			var accountMonitor = pair.Value;            

			var info = accountMonitor.GetContainerInfo(filePath);

			var containerProperties = new ContainerPropertiesViewModel(this, info,filePath);

			_windowManager.ShowWindow(containerProperties);

		}

		public void SynchNow()

		{

			_pollAgent.SynchNow();

		}

		public ObjectInfo RefreshObjectInfo(ObjectInfo currentInfo)

		{

			if (currentInfo==null)

				throw new ArgumentNullException("currentInfo");

			Contract.EndContractBlock();

			var monitor = Monitors[currentInfo.Account];

			var newInfo=monitor.CloudClient.GetObjectInfo(currentInfo.Account, currentInfo.Container, currentInfo.Name);

			return newInfo;

		}

		public ContainerInfo RefreshContainerInfo(ContainerInfo container)

		{

			if (container == null)

				throw new ArgumentNullException("container");

			Contract.EndContractBlock();

			var monitor = Monitors[container.Account];

			var newInfo = monitor.CloudClient.GetContainerInfo(container.Account, container.Name);

			return newInfo;

		}

		public void ToggleSynching()

		{

			bool isPaused=false;

			foreach (var pair in Monitors)

			{

				var monitor = pair.Value;

				monitor.Pause = !monitor.Pause;

				isPaused = monitor.Pause;

			}

			PauseSyncCaption = isPaused ? "Resume syncing" : "Pause syncing";

			var iconKey = isPaused? "TraySyncPaused" : "TrayInSynch";

			StatusIcon = String.Format(@"../Images/{0}.ico", iconKey);

		}

		public void ExitPithos()

		{

			foreach (var pair in Monitors)

			{

				var monitor = pair.Value;

				monitor.Stop();

			}

			((Window)GetView()).Close();

		}

		#endregion

		private readonly Dictionary<PithosStatus, StatusInfo> _iconNames = new List<StatusInfo>

			{

				new StatusInfo(PithosStatus.InSynch, "All files up to date", "TrayInSynch"),

				new StatusInfo(PithosStatus.PollSyncing, "Polling Files", "TraySynching"),

                new StatusInfo(PithosStatus.LocalSyncing, "Syncing Files", "TraySynching"),

				new StatusInfo(PithosStatus.SyncPaused, "Sync Paused", "TraySyncPaused")

			}.ToDictionary(s => s.Status);

		readonly IWindowManager _windowManager;

        //private int _syncCount=0;

        private PithosStatus _pithosStatus = PithosStatus.Disconnected;

        public void SetPithosStatus(PithosStatus status)

        {

            if (_pithosStatus == PithosStatus.LocalSyncing && status == PithosStatus.PollComplete)

                return;

            if (_pithosStatus == PithosStatus.PollSyncing && status == PithosStatus.LocalComplete)

                return;

            if (status == PithosStatus.LocalComplete || status == PithosStatus.PollComplete)

                _pithosStatus = PithosStatus.InSynch;

            else

                _pithosStatus = status;

            UpdateStatus();

        }

        public void SetPithosStatus(PithosStatus status,string message)

        {

            StatusMessage = message;

            SetPithosStatus(status);

        }

		///<summary>

		/// Updates the visual status indicators of the application depending on status changes, e.g. icon, stat		

		///</summary>

		public void UpdateStatus()

		{

			if (_iconNames.ContainsKey(_pithosStatus))

			{

				var info = _iconNames[_pithosStatus];

				StatusIcon = String.Format(@"../Images/{0}.ico", info.IconName);

			}

            if (_pithosStatus == PithosStatus.InSynch)

                StatusMessage = "All files up to date";

		}

		private Task StartMonitor(PithosMonitor monitor,int retries=0)

		{

			return Task.Factory.StartNew(() =>

			{

				using (log4net.ThreadContext.Stacks["Monitor"].Push("Start"))

				{

					try

					{

						Log.InfoFormat("Start Monitoring {0}", monitor.UserName);

						monitor.Start();

					}

					catch (WebException exc)

					{

						if (AbandonRetry(monitor, retries))

							return;

						HttpStatusCode statusCode =HttpStatusCode.OK;

						var response = exc.Response as HttpWebResponse;

						if(response!=null)

							statusCode = response.StatusCode;

						switch (statusCode)

						{

							case HttpStatusCode.Unauthorized:

								var message = String.Format("API Key Expired for {0}. Starting Renewal",

															monitor.UserName);

								Log.Error(message, exc);

						        var account = Settings.Accounts.Find(acc => acc.AccountName == monitor.UserName);                                

						        account.IsExpired = true;

                                Notify(new ExpirationNotification(account));

								//TryAuthorize(monitor.UserName, retries).Wait();

								break;

							case HttpStatusCode.ProxyAuthenticationRequired:

								TryAuthenticateProxy(monitor,retries);

								break;

							default:

								TryLater(monitor, exc, retries);

								break;

						}

					}

					catch (Exception exc)

					{

						if (AbandonRetry(monitor, retries)) 

							return;

						TryLater(monitor,exc,retries);

					}

				}

			});

		}

		private void TryAuthenticateProxy(PithosMonitor monitor,int retries)

		{

			Execute.OnUIThread(() =>

								   {                                       

									   var proxyAccount = IoC.Get<ProxyAccountViewModel>();

										proxyAccount.Settings = Settings;

									   if (true != _windowManager.ShowDialog(proxyAccount)) 

										   return;

									   StartMonitor(monitor, retries);

									   NotifyOfPropertyChange(() => Accounts);

								   });

		}

		private bool AbandonRetry(PithosMonitor monitor, int retries)

		{

			if (retries > 1)

			{

				var message = String.Format("Monitoring of account {0} has failed too many times. Will not retry",

											monitor.UserName);

				_events.Publish(new Notification

									{Title = "Account monitoring failed", Message = message, Level = TraceLevel.Error});

				return true;

			}

			return false;

		}

	    private void TryLater(PithosMonitor monitor, Exception exc,int retries)

		{

			var message = String.Format("An exception occured. Can't start monitoring\nWill retry in 10 seconds");

			Task.Factory.StartNewDelayed(10000, () => StartMonitor(monitor,retries+1));

			_events.Publish(new Notification

								{Title = "Error", Message = message, Level = TraceLevel.Error});

			Log.Error(message, exc);

		}

		public void NotifyChange(string status, TraceLevel level=TraceLevel.Info)

		{

			StatusMessage = status;

			_events.Publish(new Notification { Title = "Pithos", Message = status, Level = level });

		}

		public void NotifyChangedFile(string filePath)

		{

            if (RecentFiles.Any(e => e.FullPath == filePath))

                return;

			IProducerConsumerCollection<FileEntry> files=RecentFiles;

			FileEntry popped;

			while (files.Count > 5)

				files.TryTake(out popped);

            var entry = new FileEntry { FullPath = filePath };

			files.TryAdd(entry);

		}

		public void NotifyAccount(AccountInfo account)

		{

			if (account== null)

				return;

			//TODO: What happens to an existing account whose Token has changed?

			account.SiteUri= String.Format("{0}/ui/?token={1}&user={2}",

				account.SiteUri, Uri.EscapeDataString(account.Token),

				Uri.EscapeDataString(account.UserName));

			if (Accounts.All(item => item.UserName != account.UserName))

				Accounts.TryAdd(account);

		}

		public void NotifyConflicts(IEnumerable<FileSystemInfo> conflictFiles, string message)

		{

			if (conflictFiles == null)

				return;

		    //Convert to list to avoid multiple iterations

            var files = conflictFiles.ToList();

			if (files.Count==0)

				return;

			UpdateStatus();

			//TODO: Create a more specific message. For now, just show a warning

			NotifyForFiles(files,message,TraceLevel.Warning);

		}

		public void NotifyForFiles(IEnumerable<FileSystemInfo> files, string message,TraceLevel level=TraceLevel.Info)

		{

			if (files == null)

				return;

			if (!files.Any())

				return;

			StatusMessage = message;

			_events.Publish(new Notification { Title = "Pithos", Message = message, Level = level});

		}

		public void Notify(Notification notification)

		{

			_events.Publish(notification);

		}

		public void RemoveMonitor(string accountName)

		{

			if (String.IsNullOrWhiteSpace(accountName))

				return;

			var accountInfo=_accounts.FirstOrDefault(account => account.UserName == accountName);

            if (accountInfo != null)

            {

                _accounts.TryRemove(accountInfo);

                _pollAgent.RemoveAccount(accountInfo);

            }

		    PithosMonitor monitor;

			if (Monitors.TryRemove(accountName, out monitor))

			{

				monitor.Stop();

                //TODO: Also remove any pending actions for this account

                //from the network queue                

			}

		}

		public void RefreshOverlays()

		{

			foreach (var pair in Monitors)

			{

				var monitor = pair.Value;

				var path = monitor.RootPath;

				if (String.IsNullOrWhiteSpace(path))

					continue;

				if (!Directory.Exists(path) && !File.Exists(path))

					continue;

				IntPtr pathPointer = Marshal.StringToCoTaskMemAuto(path);

				try

				{

					NativeMethods.SHChangeNotify(HChangeNotifyEventID.SHCNE_UPDATEITEM,

												 HChangeNotifyFlags.SHCNF_PATHW | HChangeNotifyFlags.SHCNF_FLUSHNOWAIT,

												 pathPointer, IntPtr.Zero);

				}

				finally

				{

					Marshal.FreeHGlobal(pathPointer);

				}

			}

		}

		#region Event Handlers

		public void Handle(SelectiveSynchChanges message)

		{

			var accountName = message.Account.AccountName;

			PithosMonitor monitor;

			if (_monitors.TryGetValue(accountName, out monitor))

			{

				monitor.SetSelectivePaths(message.Uris,message.Added,message.Removed);

			}

		}

		private bool _pollStarted;

	    private Sparkle _sparkle;

	    //SMELL: Doing so much work for notifications in the shell is wrong

		//The notifications should be moved to their own view/viewmodel pair

		//and different templates should be used for different message types

		//This will also allow the addition of extra functionality, eg. actions

		//

		public void Handle(Notification notification)

		{

			UpdateStatus();

			if (!Settings.ShowDesktopNotifications)

				return;

			if (notification is PollNotification)

			{

				_pollStarted = true;

				return;

			}

			if (notification is CloudNotification)

			{

				if (!_pollStarted) 

					return;

				_pollStarted= false;

				notification.Title = "Pithos";

				notification.Message = "Start Synchronisation";

			}

		    var progress = notification as ProgressNotification;

		    if (progress != null)

		    {

		        StatusMessage = String.Format("Pithos {0}\r\n{1} {2:p2} of {3} - {4}",

		                                      _fileVersion.Value.FileVersion, 

                                              progress.Action,

		                                      progress.Block/(double)progress.TotalBlocks,

		                                      progress.FileSize.ToByteSize(),

		                                      progress.FileName);

		        return;

		    }

		    var info = notification as StatusNotification;

            if (info != null)

            {

                StatusMessage = String.Format("Pithos {0}\r\n{1}",

                                              _fileVersion.Value.FileVersion,

                                              info.Title);

                return;

            }

			if (String.IsNullOrWhiteSpace(notification.Message) && String.IsNullOrWhiteSpace(notification.Title))

				return;

			ShowBalloonFor(notification);

		}

	    private void ShowBalloonFor(Notification notification)

	    {

            Contract.Requires(notification!=null);

            if (!Settings.ShowDesktopNotifications) 

                return;

            BalloonIcon icon;

	        switch (notification.Level)

	        {

	            case TraceLevel.Info:

	            case TraceLevel.Verbose:

	                return;

                case TraceLevel.Error:

                    icon = BalloonIcon.Error;

                    break;

                case TraceLevel.Warning:

	                icon = BalloonIcon.Warning;

	                break;

	            default:

	                return;

	        }

	        var tv = (ShellView) GetView();

	        System.Action clickAction = null;

	        if (notification is ExpirationNotification)

	        {

	            clickAction = () => ShowPreferences("AccountTab");

	        }

	        var balloon = new PithosBalloon

	                          {

	                              Title = notification.Title,

	                              Message = notification.Message,

	                              Icon = icon,

	                              ClickAction = clickAction

	                          };

	        tv.TaskbarView.ShowCustomBalloon(balloon, PopupAnimation.Fade, 4000);

	    }

	    #endregion

		public void Handle(ShowFilePropertiesEvent message)

		{

			if (message == null)

				throw new ArgumentNullException("message");

			if (String.IsNullOrWhiteSpace(message.FileName) )

				throw new ArgumentException("message");

			Contract.EndContractBlock();

			var fileName = message.FileName;

			//TODO: Display file properties for non-container folders

			if (File.Exists(fileName))

				//Retrieve the full name with exact casing. Pithos names are case sensitive				

				ShowFileProperties(FileInfoExtensions.GetProperFilePathCapitalization(fileName));

			else if (Directory.Exists(fileName))

				//Retrieve the full name with exact casing. Pithos names are case sensitive

			{

				var path = FileInfoExtensions.GetProperDirectoryCapitalization(fileName);

				if (IsContainer(path))

					ShowContainerProperties(path);

				else

					ShowFileProperties(path);

			}

		}

		private bool IsContainer(string path)

		{

			var matchingFolders = from account in _accounts

								  from rootFolder in Directory.GetDirectories(account.AccountPath)

								  where rootFolder.Equals(path, StringComparison.InvariantCultureIgnoreCase)

								  select rootFolder;

			return matchingFolders.Any();

		}

		public FileStatus GetFileStatus(string localFileName)

		{

			if (String.IsNullOrWhiteSpace(localFileName))

				throw new ArgumentNullException("localFileName");

			Contract.EndContractBlock();

			var statusKeeper = IoC.Get<IStatusKeeper>();

			var status=statusKeeper.GetFileStatus(localFileName);

			return status;

		}

	}

}