// Copyright (c) Microsoft Corporation. All rights reserved. See License.txt in the project root for license information.

using System.Collections.Generic;
using System.Threading;
using Moq;
using Xunit;
using Assert = Microsoft.TestCommon.AssertEx;

namespace System.Web.Mvc.Async.Test
{
    public class AsyncControllerActionInvokerTest
    {
        [Fact]
        public void InvokeAction_ActionNotFound()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act
            IAsyncResult asyncResult = invoker.BeginInvokeAction(controllerContext, "ActionNotFound", null, null);
            bool retVal = invoker.EndInvokeAction(asyncResult);

            // Assert
            Assert.False(retVal);
        }

        [Fact]
        public void InvokeAction_ActionThrowsException_Handled()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            IAsyncResult asyncResult = invoker.BeginInvokeAction(controllerContext, "ActionThrowsExceptionAndIsHandled", null, null);
            Assert.Null(((TestController)controllerContext.Controller).Log); // Result filter shouldn't have executed yet

            bool retVal = invoker.EndInvokeAction(asyncResult);
            Assert.True(retVal);
            Assert.Equal("From exception filter", ((TestController)controllerContext.Controller).Log);
        }

        [Fact]
        public void InvokeAction_ActionThrowsException_NotHandled()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            Assert.Throws<Exception>(
                delegate { invoker.BeginInvokeAction(controllerContext, "ActionThrowsExceptionAndIsNotHandled", null, null); },
                @"Some exception text.");
        }

        [Fact]
        public void InvokeAction_ActionThrowsException_ThreadAbort()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            Assert.Throws<ThreadAbortException>(
                delegate { invoker.BeginInvokeAction(controllerContext, "ActionCallsThreadAbort", null, null); });
        }

        [Fact]
        public void InvokeAction_AuthorizationFilterShortCircuits()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act
            IAsyncResult asyncResult = invoker.BeginInvokeAction(controllerContext, "AuthorizationFilterShortCircuits", null, null);
            bool retVal = invoker.EndInvokeAction(asyncResult);

            // Assert
            Assert.True(retVal);
            Assert.Equal("From authorization filter", ((TestController)controllerContext.Controller).Log);
        }

        [Fact]
        public void InvokeAction_NormalAction()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act
            IAsyncResult asyncResult = invoker.BeginInvokeAction(controllerContext, "NormalAction", null, null);
            bool retVal = invoker.EndInvokeAction(asyncResult);

            // Assert
            Assert.True(retVal);
            Assert.Equal("From action", ((TestController)controllerContext.Controller).Log);
        }

        [Fact]
        public void InvokeAction_OverrideFindAction()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvokerWithCustomFindAction();

            // Act
            IAsyncResult asyncResult = invoker.BeginInvokeAction(controllerContext, actionName: "Non-ExistantAction", callback: null, state: null);
            bool retVal = invoker.EndInvokeAction(asyncResult);

            // Assert
            Assert.True(retVal);
            Assert.Equal("From action", ((TestController)controllerContext.Controller).Log);
        }

        [Fact]
        public void InvokeAction_RequestValidationFails()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext(passesRequestValidation: false);
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            Assert.Throws<HttpRequestValidationException>(
                delegate { invoker.BeginInvokeAction(controllerContext, "NormalAction", null, null); });
        }

        [Fact]
        public void InvokeAction_ResultThrowsException_Handled()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            IAsyncResult asyncResult = invoker.BeginInvokeAction(controllerContext, "ResultThrowsExceptionAndIsHandled", null, null);
            bool retVal = invoker.EndInvokeAction(asyncResult);

            Assert.True(retVal);
            Assert.Equal("From exception filter", ((TestController)controllerContext.Controller).Log);
        }

        [Fact]
        public void InvokeAction_ResultThrowsException_NotHandled()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            IAsyncResult asyncResult = invoker.BeginInvokeAction(controllerContext, "ResultThrowsExceptionAndIsNotHandled", null, null);
            Assert.Throws<Exception>(
                delegate { invoker.EndInvokeAction(asyncResult); },
                @"Some exception text.");
        }

        [Fact]
        public void InvokeAction_ResultThrowsException_ThreadAbort()
        {
            // Arrange
            ControllerContext controllerContext = GetControllerContext();
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            IAsyncResult asyncResult = invoker.BeginInvokeAction(controllerContext, "ResultCallsThreadAbort", null, null);
            Assert.Throws<ThreadAbortException>(
                delegate { invoker.EndInvokeAction(asyncResult); });
        }

        [Fact]
        public void InvokeAction_ThrowsIfActionNameIsEmpty()
        {
            // Arrange
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            Assert.ThrowsArgumentNullOrEmpty(
                delegate { invoker.BeginInvokeAction(new ControllerContext(), "", null, null); }, "actionName");
        }

        [Fact]
        public void InvokeAction_ThrowsIfActionNameIsNull()
        {
            // Arrange
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            Assert.ThrowsArgumentNullOrEmpty(
                delegate { invoker.BeginInvokeAction(new ControllerContext(), null, null, null); }, "actionName");
        }

        [Fact]
        public void InvokeAction_ThrowsIfControllerContextIsNull()
        {
            // Arrange
            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act & assert
            Assert.ThrowsArgumentNull(
                delegate { invoker.BeginInvokeAction(null, "someAction", null, null); }, "controllerContext");
        }

        [Fact]
        public void InvokeActionMethod_AsynchronousDescriptor()
        {
            // Arrange
            ControllerContext controllerContext = new ControllerContext();
            Dictionary<string, object> parameters = new Dictionary<string, object>();
            IAsyncResult innerAsyncResult = new MockAsyncResult();
            ActionResult expectedResult = new ViewResult();

            Mock<AsyncActionDescriptor> mockActionDescriptor = new Mock<AsyncActionDescriptor>();
            mockActionDescriptor.Setup(d => d.BeginExecute(controllerContext, parameters, It.IsAny<AsyncCallback>(), It.IsAny<object>())).Returns(innerAsyncResult);
            mockActionDescriptor.Setup(d => d.EndExecute(innerAsyncResult)).Returns(expectedResult);

            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act
            IAsyncResult asyncResult = invoker.BeginInvokeActionMethod(controllerContext, mockActionDescriptor.Object, parameters, null, null);
            ActionResult returnedResult = invoker.EndInvokeActionMethod(asyncResult);

            // Assert
            Assert.Equal(expectedResult, returnedResult);
        }

        [Fact]
        public void InvokeActionMethod_SynchronousDescriptor()
        {
            // Arrange
            ControllerContext controllerContext = new ControllerContext();
            Dictionary<string, object> parameters = new Dictionary<string, object>();
            ActionResult expectedResult = new ViewResult();

            Mock<ActionDescriptor> mockActionDescriptor = new Mock<ActionDescriptor>();
            mockActionDescriptor.Setup(d => d.Execute(controllerContext, parameters)).Returns(expectedResult);

            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();

            // Act
            IAsyncResult asyncResult = invoker.BeginInvokeActionMethod(controllerContext, mockActionDescriptor.Object, parameters, null, null);
            ActionResult returnedResult = invoker.EndInvokeActionMethod(asyncResult);

            // Assert
            Assert.Equal(expectedResult, returnedResult);
        }

        [Fact]
        public void InvokeActionMethodFilterAsynchronously_NextInChainThrowsOnActionExecutedException_Handled()
        {
            // Arrange
            ViewResult expectedResult = new ViewResult();

            bool nextInChainWasCalled = false;
            bool onActionExecutedWasCalled = false;

            ActionExecutingContext preContext = GetActionExecutingContext();
            ActionFilterImpl actionFilter = new ActionFilterImpl()
            {
                OnActionExecutedImpl = filterContext =>
                {
                    onActionExecutedWasCalled = true;
                    Assert.NotNull(filterContext.Exception);
                    filterContext.ExceptionHandled = true;
                    filterContext.Result = expectedResult;
                }
            };

            // Act & assert pre-execution
            Func<ActionExecutedContext> continuation = AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(
                actionFilter, preContext,
                () => () =>
                {
                    nextInChainWasCalled = true;
                    throw new Exception("Some exception text.");
                });

            Assert.False(onActionExecutedWasCalled);

            // Act & assert post-execution
            ActionExecutedContext postContext = continuation();

            Assert.True(nextInChainWasCalled);
            Assert.True(onActionExecutedWasCalled);
            Assert.Equal(expectedResult, postContext.Result);
        }

        [Fact]
        public void InvokeActionMethodFilterAsynchronously_NextInChainThrowsOnActionExecutedException_NotHandled()
        {
            // Arrange
            ViewResult expectedResult = new ViewResult();

            bool onActionExecutedWasCalled = false;

            ActionExecutingContext preContext = GetActionExecutingContext();
            ActionFilterImpl actionFilter = new ActionFilterImpl()
            {
                OnActionExecutedImpl = filterContext => { onActionExecutedWasCalled = true; }
            };

            // Act & assert
            Func<ActionExecutedContext> continuation = AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(actionFilter, preContext,
                                                                                                                           () => () => { throw new Exception("Some exception text."); });

            Assert.Throws<Exception>(
                delegate { continuation(); },
                @"Some exception text.");

            // Assert
            Assert.True(onActionExecutedWasCalled);
        }

        [Fact]
        public void InvokeActionMethodFilterAsynchronously_NextInChainThrowsOnActionExecutedException_ThreadAbort()
        {
            // Arrange
            ViewResult expectedResult = new ViewResult();

            bool onActionExecutedWasCalled = false;

            ActionExecutingContext preContext = GetActionExecutingContext();
            ActionFilterImpl actionFilter = new ActionFilterImpl()
            {
                OnActionExecutedImpl = filterContext =>
                {
                    onActionExecutedWasCalled = true;
                    Thread.ResetAbort();
                }
            };

            // Act & assert
            Func<ActionExecutedContext> continuation = AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(
                actionFilter, preContext,
                () => () =>
                {
                    Thread.CurrentThread.Abort();
                    return null;
                });

            Assert.Throws<ThreadAbortException>(
                delegate { continuation(); });

            // Assert
            Assert.True(onActionExecutedWasCalled);
        }

        [Fact]
        public void InvokeActionMethodFilterAsynchronously_NextInChainThrowsOnActionExecutingException_Handled()
        {
            // Arrange
            ViewResult expectedResult = new ViewResult();

            bool nextInChainWasCalled = false;
            bool onActionExecutingWasCalled = false;
            bool onActionExecutedWasCalled = false;

            ActionExecutingContext preContext = GetActionExecutingContext();
            ActionFilterImpl actionFilter = new ActionFilterImpl()
            {
                OnActionExecutingImpl = filterContext => { onActionExecutingWasCalled = true; },
                OnActionExecutedImpl = filterContext =>
                {
                    onActionExecutedWasCalled = true;
                    Assert.NotNull(filterContext.Exception);
                    filterContext.ExceptionHandled = true;
                    filterContext.Result = expectedResult;
                }
            };

            // Act
            Func<ActionExecutedContext> continuation = AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(
                actionFilter, preContext,
                () =>
                {
                    nextInChainWasCalled = true;
                    throw new Exception("Some exception text.");
                });

            // Assert
            Assert.True(nextInChainWasCalled);
            Assert.True(onActionExecutingWasCalled);
            Assert.True(onActionExecutedWasCalled);

            ActionExecutedContext postContext = continuation();
            Assert.Equal(expectedResult, postContext.Result);
        }

        [Fact]
        public void InvokeActionMethodFilterAsynchronously_NextInChainThrowsOnActionExecutingException_NotHandled()
        {
            // Arrange
            ViewResult expectedResult = new ViewResult();

            bool nextInChainWasCalled = false;
            bool onActionExecutingWasCalled = false;
            bool onActionExecutedWasCalled = false;

            ActionExecutingContext preContext = GetActionExecutingContext();
            ActionFilterImpl actionFilter = new ActionFilterImpl()
            {
                OnActionExecutingImpl = filterContext => { onActionExecutingWasCalled = true; },
                OnActionExecutedImpl = filterContext => { onActionExecutedWasCalled = true; }
            };

            // Act & assert
            Assert.Throws<Exception>(
                delegate
                {
                    AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(
                        actionFilter, preContext,
                        () =>
                        {
                            nextInChainWasCalled = true;
                            throw new Exception("Some exception text.");
                        });
                },
                @"Some exception text.");

            // Assert
            Assert.True(nextInChainWasCalled);
            Assert.True(onActionExecutingWasCalled);
            Assert.True(onActionExecutedWasCalled);
        }

        [Fact]
        public void InvokeActionMethodFilterAsynchronously_NextInChainThrowsOnActionExecutingException_ThreadAbort()
        {
            // Arrange
            ViewResult expectedResult = new ViewResult();

            bool nextInChainWasCalled = false;
            bool onActionExecutingWasCalled = false;
            bool onActionExecutedWasCalled = false;

            ActionExecutingContext preContext = GetActionExecutingContext();
            ActionFilterImpl actionFilter = new ActionFilterImpl()
            {
                OnActionExecutingImpl = filterContext => { onActionExecutingWasCalled = true; },
                OnActionExecutedImpl = filterContext =>
                {
                    onActionExecutedWasCalled = true;
                    Thread.ResetAbort();
                }
            };

            // Act & assert
            Assert.Throws<ThreadAbortException>(
                delegate
                {
                    AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(
                        actionFilter, preContext,
                        () =>
                        {
                            nextInChainWasCalled = true;
                            Thread.CurrentThread.Abort();
                            return null;
                        });
                });

            // Assert
            Assert.True(nextInChainWasCalled);
            Assert.True(onActionExecutingWasCalled);
            Assert.True(onActionExecutedWasCalled);
        }

        [Fact]
        public void InvokeActionMethodFilterAsynchronously_NormalExecutionNotCanceled()
        {
            // Arrange
            bool nextInChainWasCalled = false;
            bool onActionExecutingWasCalled = false;
            bool onActionExecutedWasCalled = false;

            ActionExecutingContext preContext = GetActionExecutingContext();
            ActionFilterImpl actionFilter = new ActionFilterImpl()
            {
                OnActionExecutingImpl = _ => { onActionExecutingWasCalled = true; },
                OnActionExecutedImpl = _ => { onActionExecutedWasCalled = true; }
            };

            // Act
            Func<ActionExecutedContext> continuation = AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(
                actionFilter, preContext,
                () =>
                {
                    nextInChainWasCalled = true;
                    return () => new ActionExecutedContext();
                });

            // Assert
            Assert.True(nextInChainWasCalled);
            Assert.True(onActionExecutingWasCalled);
            Assert.False(onActionExecutedWasCalled);

            continuation();
            Assert.True(onActionExecutedWasCalled);
        }

        [Fact]
        public void InvokeActionMethodFilterAsynchronously_OnActionExecutingSetsResult()
        {
            // Arrange
            ViewResult expectedResult = new ViewResult();

            bool nextInChainWasCalled = false;
            bool onActionExecutingWasCalled = false;
            bool onActionExecutedWasCalled = false;

            ActionExecutingContext preContext = GetActionExecutingContext();
            ActionFilterImpl actionFilter = new ActionFilterImpl()
            {
                OnActionExecutingImpl = filterContext =>
                {
                    onActionExecutingWasCalled = true;
                    filterContext.Result = expectedResult;
                },
                OnActionExecutedImpl = _ => { onActionExecutedWasCalled = true; }
            };

            // Act
            Func<ActionExecutedContext> continuation = AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(
                actionFilter, preContext,
                () =>
                {
                    nextInChainWasCalled = true;
                    return () => new ActionExecutedContext();
                });

            // Assert
            Assert.False(nextInChainWasCalled);
            Assert.True(onActionExecutingWasCalled);
            Assert.False(onActionExecutedWasCalled);

            ActionExecutedContext postContext = continuation();
            Assert.False(onActionExecutedWasCalled);
            Assert.Equal(expectedResult, postContext.Result);
        }

        [Fact]
        public void InvokeActionMethodWithFilters()
        {
            // Arrange
            List<string> actionLog = new List<string>();
            ControllerContext controllerContext = new ControllerContext();
            Dictionary<string, object> parameters = new Dictionary<string, object>();
            MockAsyncResult innerAsyncResult = new MockAsyncResult();
            ActionResult actionResult = new ViewResult();

            ActionFilterImpl filter1 = new ActionFilterImpl()
            {
                OnActionExecutingImpl = delegate(ActionExecutingContext filterContext) { actionLog.Add("OnActionExecuting1"); },
                OnActionExecutedImpl = delegate(ActionExecutedContext filterContext) { actionLog.Add("OnActionExecuted1"); }
            };
            ActionFilterImpl filter2 = new ActionFilterImpl()
            {
                OnActionExecutingImpl = delegate(ActionExecutingContext filterContext) { actionLog.Add("OnActionExecuting2"); },
                OnActionExecutedImpl = delegate(ActionExecutedContext filterContext) { actionLog.Add("OnActionExecuted2"); }
            };

            Mock<AsyncActionDescriptor> mockActionDescriptor = new Mock<AsyncActionDescriptor>();
            mockActionDescriptor.Setup(d => d.BeginExecute(controllerContext, parameters, It.IsAny<AsyncCallback>(), It.IsAny<object>())).Returns(innerAsyncResult);
            mockActionDescriptor.Setup(d => d.EndExecute(innerAsyncResult)).Returns(actionResult);

            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();
            IActionFilter[] filters = new IActionFilter[] { filter1, filter2 };

            // Act
            IAsyncResult outerAsyncResult = invoker.BeginInvokeActionMethodWithFilters(controllerContext, filters, mockActionDescriptor.Object, parameters, null, null);
            ActionExecutedContext postContext = invoker.EndInvokeActionMethodWithFilters(outerAsyncResult);

            // Assert
            Assert.Equal(new[] { "OnActionExecuting1", "OnActionExecuting2", "OnActionExecuted2", "OnActionExecuted1" }, actionLog.ToArray());
            Assert.Equal(actionResult, postContext.Result);
        }

        [Fact]
        public void InvokeActionMethodWithFilters_ShortCircuited()
        {
            // Arrange
            List<string> actionLog = new List<string>();
            ControllerContext controllerContext = new ControllerContext();
            Dictionary<string, object> parameters = new Dictionary<string, object>();
            ActionResult actionResult = new ViewResult();

            ActionFilterImpl filter1 = new ActionFilterImpl()
            {
                OnActionExecutingImpl = delegate(ActionExecutingContext filterContext) { actionLog.Add("OnActionExecuting1"); },
                OnActionExecutedImpl = delegate(ActionExecutedContext filterContext) { actionLog.Add("OnActionExecuted1"); }
            };
            ActionFilterImpl filter2 = new ActionFilterImpl()
            {
                OnActionExecutingImpl = delegate(ActionExecutingContext filterContext)
                {
                    actionLog.Add("OnActionExecuting2");
                    filterContext.Result = actionResult;
                },
                OnActionExecutedImpl = delegate(ActionExecutedContext filterContext) { actionLog.Add("OnActionExecuted2"); }
            };

            Mock<AsyncActionDescriptor> mockActionDescriptor = new Mock<AsyncActionDescriptor>();
            mockActionDescriptor.Setup(d => d.BeginExecute(controllerContext, parameters, It.IsAny<AsyncCallback>(), It.IsAny<object>())).Throws(new Exception("I shouldn't have been called."));
            mockActionDescriptor.Setup(d => d.EndExecute(It.IsAny<IAsyncResult>())).Throws(new Exception("I shouldn't have been called."));

            AsyncControllerActionInvoker invoker = new AsyncControllerActionInvoker();
            IActionFilter[] filters = new IActionFilter[] { filter1, filter2 };

            // Act
            IAsyncResult outerAsyncResult = invoker.BeginInvokeActionMethodWithFilters(controllerContext, filters, mockActionDescriptor.Object, parameters, null, null);
            ActionExecutedContext postContext = invoker.EndInvokeActionMethodWithFilters(outerAsyncResult);

            // Assert
            Assert.Equal(new[] { "OnActionExecuting1", "OnActionExecuting2", "OnActionExecuted1" }, actionLog.ToArray());
            Assert.Equal(actionResult, postContext.Result);
        }

        private static ActionExecutingContext GetActionExecutingContext()
        {
            return new ActionExecutingContext(new ControllerContext(), new Mock<ActionDescriptor>().Object, new Dictionary<string, object>());
        }

        private static ControllerContext GetControllerContext(bool passesRequestValidation = true)
        {
            Mock<HttpContextBase> mockHttpContext = new Mock<HttpContextBase>();
            if (passesRequestValidation)
            {
#pragma warning disable 618
                mockHttpContext.Setup(o => o.Request.ValidateInput()).AtMostOnce();
#pragma warning restore 618
            }
            else
            {
                mockHttpContext.Setup(o => o.Request.ValidateInput()).Throws(new HttpRequestValidationException());
            }

            return new ControllerContext()
            {
                Controller = new TestController(),
                HttpContext = mockHttpContext.Object
            };
        }

        private class ActionFilterImpl : IActionFilter, IResultFilter
        {
            public Action<ActionExecutingContext> OnActionExecutingImpl { get; set; }

            public void OnActionExecuting(ActionExecutingContext filterContext)
            {
                if (OnActionExecutingImpl != null)
                {
                    OnActionExecutingImpl(filterContext);
                }
            }

            public Action<ActionExecutedContext> OnActionExecutedImpl { get; set; }

            public void OnActionExecuted(ActionExecutedContext filterContext)
            {
                if (OnActionExecutedImpl != null)
                {
                    OnActionExecutedImpl(filterContext);
                }
            }

            public Action<ResultExecutingContext> OnResultExecutingImpl { get; set; }

            public void OnResultExecuting(ResultExecutingContext filterContext)
            {
                if (OnResultExecutingImpl != null)
                {
                    OnResultExecutingImpl(filterContext);
                }
            }

            public Action<ResultExecutedContext> OnResultExecutedImpl { get; set; }

            public void OnResultExecuted(ResultExecutedContext filterContext)
            {
                if (OnResultExecutedImpl != null)
                {
                    OnResultExecutedImpl(filterContext);
                }
            }
        }

        public class AsyncControllerActionInvokerHelper : AsyncControllerActionInvoker
        {
            public AsyncControllerActionInvokerHelper()
            {
                DescriptorCache = new ControllerDescriptorCache();
            }

            protected override ControllerDescriptor GetControllerDescriptor(ControllerContext controllerContext)
            {
                return PublicGetControllerDescriptor(controllerContext);
            }

            public virtual ControllerDescriptor PublicGetControllerDescriptor(ControllerContext controllerContext)
            {
                return base.GetControllerDescriptor(controllerContext);
            }

            protected override ExceptionContext InvokeExceptionFilters(ControllerContext controllerContext, IList<IExceptionFilter> filters, Exception exception)
            {
                return PublicInvokeExceptionFilters(controllerContext, filters, exception);
            }

            public virtual ExceptionContext PublicInvokeExceptionFilters(ControllerContext controllerContext, IList<IExceptionFilter> filters, Exception exception)
            {
                return base.InvokeExceptionFilters(controllerContext, filters, exception);
            }

            protected override void InvokeActionResult(ControllerContext controllerContext, ActionResult actionResult)
            {
                PublicInvokeActionResult(controllerContext, actionResult);
            }

            public virtual void PublicInvokeActionResult(ControllerContext controllerContext, ActionResult actionResult)
            {
                base.InvokeActionResult(controllerContext, actionResult);
            }

            protected override FilterInfo GetFilters(ControllerContext controllerContext, ActionDescriptor actionDescriptor)
            {
                return PublicGetFilters(controllerContext, actionDescriptor);
            }

            public virtual FilterInfo PublicGetFilters(ControllerContext controllerContext, ActionDescriptor actionDescriptor)
            {
                return base.GetFilters(controllerContext, actionDescriptor);
            }

            protected override AuthorizationContext InvokeAuthorizationFilters(ControllerContext controllerContext, IList<IAuthorizationFilter> filters, ActionDescriptor actionDescriptor)
            {
                return PublicInvokeAuthorizationFilters(controllerContext, filters, actionDescriptor);
            }

            public virtual AuthorizationContext PublicInvokeAuthorizationFilters(ControllerContext controllerContext, IList<IAuthorizationFilter> filters, ActionDescriptor actionDescriptor)
            {
                return base.InvokeAuthorizationFilters(controllerContext, filters, actionDescriptor);
            }

            protected override ActionDescriptor FindAction(ControllerContext controllerContext, ControllerDescriptor controllerDescriptor, string actionName)
            {
                return PublicFindAction(controllerContext, controllerDescriptor, actionName);
            }

            public virtual ActionDescriptor PublicFindAction(ControllerContext controllerContext, ControllerDescriptor controllerDescriptor, string actionName)
            {
                return base.FindAction(controllerContext, controllerDescriptor, actionName);
            }

            protected override IDictionary<string, object> GetParameterValues(ControllerContext controllerContext, ActionDescriptor actionDescriptor)
            {
                return PublicGetParameterValues(controllerContext, actionDescriptor);
            }

            public virtual IDictionary<string, object> PublicGetParameterValues(ControllerContext controllerContext, ActionDescriptor actionDescriptor)
            {
                return base.GetParameterValues(controllerContext, actionDescriptor);
            }
        }

        public class AsyncControllerActionInvokerWithCustomFindAction : AsyncControllerActionInvoker
        {
            protected override ActionDescriptor FindAction(ControllerContext controllerContext, ControllerDescriptor controllerDescriptor, string actionName)
            {
                return base.FindAction(controllerContext, controllerDescriptor, "NormalAction");
            }
        }

        [ResetThreadAbort]
        private class TestController : AsyncController
        {
            public string Log;

            public ActionResult ActionCallsThreadAbortAsync()
            {
                Thread.CurrentThread.Abort();
                return null;
            }

            public ActionResult ActionCallsThreadAbortCompleted()
            {
                return null;
            }

            public ActionResult ResultCallsThreadAbort()
            {
                return new ActionResultWhichCallsThreadAbort();
            }

            public ActionResult NormalAction()
            {
                return new LoggingActionResult("From action");
            }

            [AuthorizationFilterReturnsResult]
            public void AuthorizationFilterShortCircuits()
            {
            }

            [CustomExceptionFilterHandlesError]
            public void ActionThrowsExceptionAndIsHandledAsync()
            {
                throw new Exception("Some exception text.");
            }

            public void ActionThrowsExceptionAndIsHandledCompleted()
            {
            }

            [CustomExceptionFilterDoesNotHandleError]
            public void ActionThrowsExceptionAndIsNotHandledAsync()
            {
                throw new Exception("Some exception text.");
            }

            public void ActionThrowsExceptionAndIsNotHandledCompleted()
            {
            }

            [CustomExceptionFilterHandlesError]
            public ActionResult ResultThrowsExceptionAndIsHandled()
            {
                return new ActionResultWhichThrowsException();
            }

            [CustomExceptionFilterDoesNotHandleError]
            public ActionResult ResultThrowsExceptionAndIsNotHandled()
            {
                return new ActionResultWhichThrowsException();
            }

            private class AuthorizationFilterReturnsResultAttribute : FilterAttribute, IAuthorizationFilter
            {
                public void OnAuthorization(AuthorizationContext filterContext)
                {
                    filterContext.Result = new LoggingActionResult("From authorization filter");
                }
            }

            private class CustomExceptionFilterDoesNotHandleErrorAttribute : FilterAttribute, IExceptionFilter
            {
                public void OnException(ExceptionContext filterContext)
                {
                }
            }

            private class CustomExceptionFilterHandlesErrorAttribute : FilterAttribute, IExceptionFilter
            {
                public void OnException(ExceptionContext filterContext)
                {
                    filterContext.ExceptionHandled = true;
                    filterContext.Result = new LoggingActionResult("From exception filter");
                }
            }

            private class ActionResultWhichCallsThreadAbort : ActionResult
            {
                public override void ExecuteResult(ControllerContext context)
                {
                    Thread.CurrentThread.Abort();
                }
            }

            private class ActionResultWhichThrowsException : ActionResult
            {
                public override void ExecuteResult(ControllerContext context)
                {
                    throw new Exception("Some exception text.");
                }
            }
        }

        private class ResetThreadAbortAttribute : ActionFilterAttribute
        {
            public override void OnActionExecuted(ActionExecutedContext filterContext)
            {
                try
                {
                    Thread.ResetAbort();
                }
                catch (ThreadStateException)
                {
                    // thread wasn't being aborted
                }
            }

            public override void OnResultExecuted(ResultExecutedContext filterContext)
            {
                try
                {
                    Thread.ResetAbort();
                }
                catch (ThreadStateException)
                {
                    // thread wasn't being aborted
                }
            }
        }

        private class LoggingActionResult : ActionResult
        {
            private readonly string _logText;

            public LoggingActionResult(string logText)
            {
                _logText = logText;
            }

            public override void ExecuteResult(ControllerContext context)
            {
                ((TestController)context.Controller).Log = _logText;
            }
        }
    }
}