using NUnit.Framework;
using System.Threading.Tasks;
using TINK.ViewModel;

namespace TestTINKLib.Fixtures.ObjectTests
{
    [TestFixture]
    public class TestPollingUpdateTask
    {
        /// <summary>
        /// Verify that no exception is thrown when invoking Terminate.
        /// </summary>
        [Test]
        public async Task TestCtorPollingOff()
        {
            var task = new PollingUpdateTask(() => throw new System.Exception("This must not be called."), null);

            await task.Terminate();
        }

        [Test]
        public async Task TestCtorPollingOn()
        {
            int index = 0;
            var task = new PollingUpdateTask(() => index++, new System.TimeSpan(10));
            
            System.Threading.SpinWait.SpinUntil(() => index > 2);

            await task.Terminate();

            Assert.That(index, Is.AtLeast(3), "Delegate which increments index must be called.");
        }

        [Test]
        public void TestTerminateRepeated()
        {
            var tasks = new PollingUpdateTask(async () => await Task.Delay(1000), new System.TimeSpan(0, 0, 2));

            tasks.Terminate().Wait();

            // Verify that calling terminate twice does not lead to hang of call.
            tasks.Terminate().Wait();
        }
    }
}