// ****************************************************************

// Copyright 2007, Charlie Poole

// This is free software licensed under the NUnit license. You may

// obtain a copy of the license at http://nunit.org

// ****************************************************************



using System;

using System.Collections;

using NUnit.Core;



namespace NUnit.Util

{

	/// <summary>

	/// Summary description for ServiceManger.

	/// </summary>

	public class ServiceManager

	{

		private ArrayList services = new ArrayList();

		private Hashtable serviceIndex = new Hashtable();



		private static ServiceManager defaultServiceManager = new ServiceManager();



		static Logger log = InternalTrace.GetLogger(typeof(ServiceManager));



		public static ServiceManager Services

		{

			get { return defaultServiceManager; }

		}



		public void AddService( IService service )

		{

			services.Add( service );

			log.Debug( "Added " + service.GetType().Name );

		}



		public IService GetService( Type serviceType )

		{

			IService theService = (IService)serviceIndex[serviceType];

			if ( theService == null )

				foreach( IService service in services )

				{

					// TODO: Does this work on Mono?

					if( serviceType.IsInstanceOfType( service ) )

					{

						serviceIndex[serviceType] = service;

						theService = service;

						break;

					}

				}



			if ( theService == null )

				log.Error( string.Format( "Requested service {0} was not found", serviceType.FullName ) );

			else

				log.Debug( string.Format( "Request for service {0} satisfied by {1}", serviceType.Name, theService.GetType().Name ) );

			

			return theService;

		}



		public void InitializeServices()

		{

			foreach( IService service in services )

			{

				log.Info( "Initializing " + service.GetType().Name );

                try

                {

                    service.InitializeService();

                }

                catch (Exception ex)

                {

                    log.Error("Failed to initialize service", ex);

                }

			}

		}



		public void StopAllServices()

		{

			// Stop services in reverse of initialization order

			// TODO: Deal with dependencies explicitly

			int index = services.Count;

            while (--index >= 0)

            {

                IService service = services[index] as IService;

                log.Info( "Stopping " + service.GetType().Name );

                try

                {

                    service.UnloadService();

                }

                catch (Exception ex)

                {

                    log.Error("Failure stopping service", ex);

                }

            }

		}



		public void ClearServices()

		{

            log.Info("Clearing Service list");

			services.Clear();

		}



		private ServiceManager() { }

	}

}