/src/TecX/TecX.Event.Test/EventAggregatorFixture.cs

namespace TecX.Event.Test

{

    using System;

    using System.Threading;

    using System.Windows.Threading;



    using Microsoft.VisualStudio.TestTools.UnitTesting;



    using TecX.Event.Test.TestObjects;

    using TecX.TestTools;



    [TestClass]

    public class EventAggregatorFixture

    {

        [TestMethod]

        public void CanPublishMessageOnSameThread()

        {

            Dispatcher dispatcher = Dispatcher.CurrentDispatcher;



            IEventAggregator eventAggregator = new EventAggregator(dispatcher);



            SimpleSubscriber subscriber = new SimpleSubscriber();



            eventAggregator.Subscribe(subscriber);



            eventAggregator.Publish(new SimpleMessage());



            DispatcherUtil.DoEvents();



            Assert.IsTrue(subscriber.MessageReceived);

            Assert.AreEqual(1, subscriber.MessageCounter);

        }



        [TestMethod]

        public void CanPublishMessageOnDifferentThread()

        {

            Dispatcher dispatcher = Dispatcher.CurrentDispatcher;



            IEventAggregator eventAggregator = new EventAggregator(dispatcher);



            SimpleSubscriber subscriber = new SimpleSubscriber();



            eventAggregator.Subscribe(subscriber);



            ManualResetEvent manualResetEvent = new ManualResetEvent(false);



            ParameterizedThreadStart start = parameter =>

                                                 {

                                                     IEventAggregator ea =

                                                         parameter as IEventAggregator;



                                                     Assert.IsNotNull(ea);



                                                     ea.Publish(new SimpleMessage());



                                                     manualResetEvent.Set();

                                                 };



            Thread thread = new Thread(start);



            thread.Start(eventAggregator);



            manualResetEvent.WaitOne(1000, false);



            DispatcherUtil.DoEvents();



            Assert.IsTrue(subscriber.MessageReceived);

            Assert.AreEqual(1, subscriber.MessageCounter);

        }



        [TestMethod]

        public void WhenSubscribingMultipleTimes_RepeatedSubscriptionsAreIgnored()

        {

            Dispatcher dispatcher = Dispatcher.CurrentDispatcher;



            IEventAggregator eventAggregator = new EventAggregator(dispatcher);



            SimpleSubscriber subscriber = new SimpleSubscriber();



            eventAggregator.Subscribe(subscriber);



            //try to subscribe for the second time

            eventAggregator.Subscribe(subscriber);



            eventAggregator.Publish(new SimpleMessage());



            DispatcherUtil.DoEvents();



            Assert.IsTrue(subscriber.MessageReceived);

            Assert.AreEqual(1, subscriber.MessageCounter);

        }



        [TestMethod]

        public void WhenPublishingWithCancelOption_CancellationTokenIsReturned()

        {

            Dispatcher dispatcher = Dispatcher.CurrentDispatcher;



            IEventAggregator eventAggregator = new EventAggregator(dispatcher);



            CancelingSubscriber subscriber = new CancelingSubscriber();



            eventAggregator.Subscribe(subscriber);



            CancelMessage token = eventAggregator.Publish(new CancelMessage());



            DispatcherUtil.DoEvents();



            Assert.IsTrue(token.Cancel);

        }



        [TestMethod]

        public void WhenUnsubscribing_SubscriberIsRemoved()

        {

            Dispatcher dispatcher = Dispatcher.CurrentDispatcher;



            IEventAggregator eventAggregator = new EventAggregator(dispatcher);



            OneTimeSubscriber subscriber = new OneTimeSubscriber();



            eventAggregator.Subscribe(subscriber);



            eventAggregator.Publish(new SimpleMessage());



            eventAggregator.Unsubscribe(subscriber);



            eventAggregator.Publish(new SimpleMessage());





            DispatcherUtil.DoEvents();



            Assert.AreEqual(1, subscriber.Counter);

        }



        [TestMethod]

        [ExpectedException(typeof(ArgumentException))]

        public void WhenSubscribingObjectThatDoesNotImplementHandlerInterface_ExceptionIsThrown()

        {

            Dispatcher dispatcher = Dispatcher.CurrentDispatcher;



            IEventAggregator eventAggregator = new EventAggregator(dispatcher);



            eventAggregator.Subscribe(new object());

        }

    }

}