// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

#if DNX451
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq.Expressions;
using System.Threading.Tasks;
using Microsoft.AspNet.Http;
using Microsoft.AspNet.Mvc.ModelBinding;
using Microsoft.AspNet.Mvc.ModelBinding.Validation;
using Moq;
using Xunit;

namespace Microsoft.AspNet.Mvc.Test
{
    public class ModelBindingHelperTest
    {
        [Fact]
        public async Task TryUpdateModel_ReturnsFalse_IfBinderReturnsNull()
        {
            // Arrange
            var metadataProvider = new EmptyModelMetadataProvider();

            var binder = new Mock<IModelBinder>();
            binder.Setup(b => b.BindModelAsync(It.IsAny<ModelBindingContext>()))
                  .Returns(Task.FromResult<ModelBindingResult>(null));
            var model = new MyModel();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                model,
                null,
                Mock.Of<HttpContext>(),
                new ModelStateDictionary(),
                metadataProvider,
                GetCompositeBinder(binder.Object),
                Mock.Of<IValueProvider>(),
                new List<IInputFormatter>(),
                new DefaultObjectValidator(new IExcludeTypeValidationFilter[0], metadataProvider),
                Mock.Of<IModelValidatorProvider>());

            // Assert
            Assert.False(result);
            Assert.Null(model.MyProperty);
        }

        [Fact]
        public async Task TryUpdateModel_ReturnsFalse_IfModelValidationFails()
        {
            // Arrange
            // Mono issue - https://github.com/aspnet/External/issues/19
            var expectedMessage = PlatformNormalizer.NormalizeContent("The MyProperty field is required.");
            var binders = new IModelBinder[]
            {
                new TypeConverterModelBinder(),
                new ComplexModelDtoModelBinder(),
                new MutableObjectModelBinder()
            };

            var validator = new DataAnnotationsModelValidatorProvider();
            var model = new MyModel();
            var modelStateDictionary = new ModelStateDictionary();
            var values = new Dictionary<string, object>
            {
                { "", null }
            };
            var valueProvider = new TestValueProvider(values);
            var modelMetadataProvider = TestModelMetadataProvider.CreateDefaultProvider();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                model,
                "",
                Mock.Of<HttpContext>(),
                modelStateDictionary,
                modelMetadataProvider,
                GetCompositeBinder(binders),
                valueProvider,
                new List<IInputFormatter>(),
                new DefaultObjectValidator(new IExcludeTypeValidationFilter[0], modelMetadataProvider),
                validator);

            // Assert
            Assert.False(result);
            var error = Assert.Single(modelStateDictionary["MyProperty"].Errors);
            Assert.Equal(expectedMessage, error.ErrorMessage);
        }

        [Fact]
        public async Task TryUpdateModel_ReturnsTrue_IfModelBindsAndValidatesSuccessfully()
        {
            // Arrange
            var binders = new IModelBinder[]
            {
                new TypeConverterModelBinder(),
                new ComplexModelDtoModelBinder(),
                new MutableObjectModelBinder()
            };

            var validator = new DataAnnotationsModelValidatorProvider();
            var model = new MyModel { MyProperty = "Old-Value" };
            var modelStateDictionary = new ModelStateDictionary();
            var values = new Dictionary<string, object>
            {
                { "", null },
                { "MyProperty", "MyPropertyValue" }
            };
            var valueProvider = new TestValueProvider(values);
            var metadataProvider = TestModelMetadataProvider.CreateDefaultProvider();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                model,
                "",
                Mock.Of<HttpContext>(),
                modelStateDictionary,
                metadataProvider,
                GetCompositeBinder(binders),
                valueProvider,
                new List<IInputFormatter>(),
                new DefaultObjectValidator(new IExcludeTypeValidationFilter[0], metadataProvider),
                validator);

            // Assert
            Assert.True(result);
            Assert.Equal("MyPropertyValue", model.MyProperty);
        }

        [Fact]
        public async Task TryUpdateModel_UsingIncludePredicateOverload_ReturnsFalse_IfBinderReturnsNull()
        {
            // Arrange
            var metadataProvider = new EmptyModelMetadataProvider();

            var binder = new Mock<IModelBinder>();
            binder.Setup(b => b.BindModelAsync(It.IsAny<ModelBindingContext>()))
                  .Returns(Task.FromResult<ModelBindingResult>(null));
            var model = new MyModel();
            Func<ModelBindingContext, string, bool> includePredicate =
               (context, propertyName) => true;
            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                model,
                null,
                Mock.Of<HttpContext>(),
                new ModelStateDictionary(),
                metadataProvider,
                GetCompositeBinder(binder.Object),
                Mock.Of<IValueProvider>(),
                new List<IInputFormatter>(),
                Mock.Of<IObjectModelValidator>(),
                Mock.Of<IModelValidatorProvider>(),
                includePredicate);

            // Assert
            Assert.False(result);
            Assert.Null(model.MyProperty);
            Assert.Null(model.IncludedProperty);
            Assert.Null(model.ExcludedProperty);
        }

        [Fact]
        public async Task TryUpdateModel_UsingIncludePredicateOverload_ReturnsTrue_ModelBindsAndValidatesSuccessfully()
        {
            // Arrange
            var binders = new IModelBinder[]
            {
                new TypeConverterModelBinder(),
                new ComplexModelDtoModelBinder(),
                new MutableObjectModelBinder()
            };

            var validator = new DataAnnotationsModelValidatorProvider();
            var model = new MyModel {
                MyProperty = "Old-Value",
                IncludedProperty = "Old-IncludedPropertyValue",
                ExcludedProperty = "Old-ExcludedPropertyValue"
            };

            var modelStateDictionary = new ModelStateDictionary();
            var values = new Dictionary<string, object>
            {
                { "", null },
                { "MyProperty", "MyPropertyValue" },
                { "IncludedProperty", "IncludedPropertyValue" },
                { "ExcludedProperty", "ExcludedPropertyValue" }
            };

            Func<ModelBindingContext, string, bool> includePredicate =
                (context, propertyName) =>
                                string.Equals(propertyName, "IncludedProperty", StringComparison.OrdinalIgnoreCase) ||
                                string.Equals(propertyName, "MyProperty", StringComparison.OrdinalIgnoreCase);

            var valueProvider = new TestValueProvider(values);
            var metadataProvider = TestModelMetadataProvider.CreateDefaultProvider();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                model,
                "",
                Mock.Of<HttpContext>(),
                modelStateDictionary,
                metadataProvider,
                GetCompositeBinder(binders),
                valueProvider,
                new List<IInputFormatter>(),
                new DefaultObjectValidator(new IExcludeTypeValidationFilter[0], metadataProvider),
                validator,
                includePredicate);

            // Assert
            Assert.True(result);
            Assert.Equal("MyPropertyValue", model.MyProperty);
            Assert.Equal("IncludedPropertyValue", model.IncludedProperty);
            Assert.Equal("Old-ExcludedPropertyValue", model.ExcludedProperty);
        }

        [Fact]
        public async Task TryUpdateModel_UsingIncludeExpressionOverload_ReturnsFalse_IfBinderReturnsNull()
        {
            // Arrange
            var metadataProvider = new EmptyModelMetadataProvider();

            var binder = new Mock<IModelBinder>();
            binder.Setup(b => b.BindModelAsync(It.IsAny<ModelBindingContext>()))
                  .Returns(Task.FromResult<ModelBindingResult>(null));
            var model = new MyModel();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                                                    model,
                                                    null,
                                                    Mock.Of<HttpContext>(),
                                                    new ModelStateDictionary(),
                                                    metadataProvider,
                                                    GetCompositeBinder(binder.Object),
                                                    Mock.Of<IValueProvider>(),
                                                    new List<IInputFormatter>(),
                                                    Mock.Of<IObjectModelValidator>(),
                                                    Mock.Of<IModelValidatorProvider>(),
                                                    m => m.IncludedProperty );

            // Assert
            Assert.False(result);
            Assert.Null(model.MyProperty);
            Assert.Null(model.IncludedProperty);
            Assert.Null(model.ExcludedProperty);
        }

        [Fact]
        public async Task TryUpdateModel_UsingIncludeExpressionOverload_ReturnsTrue_ModelBindsAndValidatesSuccessfully()
        {
            // Arrange
            var binders = new IModelBinder[]
            {
                new TypeConverterModelBinder(),
                new ComplexModelDtoModelBinder(),
                new MutableObjectModelBinder()
            };

            var validator = new DataAnnotationsModelValidatorProvider();
            var model = new MyModel
            {
                MyProperty = "Old-Value",
                IncludedProperty = "Old-IncludedPropertyValue",
                ExcludedProperty = "Old-ExcludedPropertyValue"
            };

            var modelStateDictionary = new ModelStateDictionary();
            var values = new Dictionary<string, object>
            {
                { "", null },
                { "MyProperty", "MyPropertyValue" },
                { "IncludedProperty", "IncludedPropertyValue" },
                { "ExcludedProperty", "ExcludedPropertyValue" }
            };

            var valueProvider = new TestValueProvider(values);
            var metadataProvider = TestModelMetadataProvider.CreateDefaultProvider();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                model,
                "",
                Mock.Of<HttpContext>(),
                modelStateDictionary,
                TestModelMetadataProvider.CreateDefaultProvider(),
                GetCompositeBinder(binders),
                valueProvider,
                new List<IInputFormatter>(),
                new DefaultObjectValidator(new IExcludeTypeValidationFilter[0], metadataProvider),
                validator,
                m => m.IncludedProperty,
                m => m.MyProperty);

            // Assert
            Assert.True(result);
            Assert.Equal("MyPropertyValue", model.MyProperty);
            Assert.Equal("IncludedPropertyValue", model.IncludedProperty);
            Assert.Equal("Old-ExcludedPropertyValue", model.ExcludedProperty);
        }

        [Fact]
        public async Task TryUpdateModel_UsingDefaultIncludeOverload_IncludesAllProperties()
        {
            // Arrange
            var binders = new IModelBinder[]
            {
                new TypeConverterModelBinder(),
                new ComplexModelDtoModelBinder(),
                new MutableObjectModelBinder()
            };

            var validator = new DataAnnotationsModelValidatorProvider();
            var model = new MyModel
            {
                MyProperty = "Old-Value",
                IncludedProperty = "Old-IncludedPropertyValue",
                ExcludedProperty = "Old-ExcludedPropertyValue"
            };

            var modelStateDictionary = new ModelStateDictionary();
            var values = new Dictionary<string, object>
            {
                { "", null },
                { "MyProperty", "MyPropertyValue" },
                { "IncludedProperty", "IncludedPropertyValue" },
                { "ExcludedProperty", "ExcludedPropertyValue" }
            };

            var valueProvider = new TestValueProvider(values);
            var metadataProvider = TestModelMetadataProvider.CreateDefaultProvider();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                model,
                "",
                Mock.Of<HttpContext>(),
                modelStateDictionary,
                metadataProvider,
                GetCompositeBinder(binders),
                valueProvider,
                new List<IInputFormatter>(),
                new DefaultObjectValidator(new IExcludeTypeValidationFilter[0], metadataProvider),
                validator);

            // Assert
            // Includes everything.
            Assert.True(result);
            Assert.Equal("MyPropertyValue", model.MyProperty);
            Assert.Equal("IncludedPropertyValue", model.IncludedProperty);
            Assert.Equal("ExcludedPropertyValue", model.ExcludedProperty);
        }

        [Fact]
        public void GetPropertyName_PropertyMemberAccessReturnsPropertyName()
        {
            // Arrange
            Expression<Func<User, object>> expression = m => m.Address;

            // Act
            var propertyName = ModelBindingHelper.GetPropertyName(expression.Body);

            // Assert
            Assert.Equal(nameof(User.Address), propertyName);
        }

        [Fact]
        public void GetPropertyName_ChainedExpression_Throws()
        {
            // Arrange
            Expression<Func<User, object>> expression = m => m.Address.Street;

            // Act & Assert
            var ex = Assert.Throws<InvalidOperationException>(() =>
                        ModelBindingHelper.GetPropertyName(expression.Body));

            Assert.Equal(string.Format("The passed expression of expression node type '{0}' is invalid." +
                                       " Only simple member access expressions for model properties are supported.",
                                        expression.Body.NodeType),
                         ex.Message);
        }

        public static IEnumerable<object[]> InvalidExpressionDataSet
        {
            get
            {
                Expression<Func<User, object>> expression = m => new Func<User>(() => m);
                yield return new object[] { expression }; // lambda expression.

                expression = m => m.Save();
                yield return new object[] { expression }; // method call expression.

                expression = m => m.Friends[0]; // ArrayIndex expression.
                yield return new object[] { expression };

                expression = m => m.Colleagues[0]; // Indexer expression.
                yield return new object[] { expression };

                expression = m => m; // Parameter expression.
                yield return new object[] { expression };

                object someVariable = "something";
                expression = m => someVariable; // Variable accessor.
                yield return new object[] { expression };
            }
        }

        [Theory]
        [MemberData(nameof(InvalidExpressionDataSet))]
        public void GetPropertyName_ExpressionsOtherThanMemberAccess_Throws(Expression<Func<User, object>> expression)
        {
            // Arrange Act & Assert
            var ex = Assert.Throws<InvalidOperationException>(() =>
                        ModelBindingHelper.GetPropertyName(expression.Body));

            Assert.Equal(string.Format("The passed expression of expression node type '{0}' is invalid."+
                                       " Only simple member access expressions for model properties are supported.",
                                        expression.Body.NodeType),
                         ex.Message);
        }

        [Fact]
        public void GetPropertyName_NonParameterBasedExpression_Throws()
        {
            // Arrange
            var someUser = new User();

            // PropertyAccessor with a property name invalid as it originates from a variable accessor.
            Expression<Func<User, object>> expression = m => someUser.Address;

            // Act & Assert
            var ex = Assert.Throws<InvalidOperationException>(() =>
                        ModelBindingHelper.GetPropertyName(expression.Body));

            Assert.Equal(string.Format("The passed expression of expression node type '{0}' is invalid." +
                                       " Only simple member access expressions for model properties are supported.",
                                        expression.Body.NodeType),
                        ex.Message);
        }

        [Fact]
        public void GetPropertyName_TopLevelCollectionIndexer_Throws()
        {
            // Arrange
            Expression<Func<List<User>, object>> expression = m => m[0];

            // Act & Assert
            var ex = Assert.Throws<InvalidOperationException>(() =>
                        ModelBindingHelper.GetPropertyName(expression.Body));

            Assert.Equal(string.Format("The passed expression of expression node type '{0}' is invalid." +
                                       " Only simple member access expressions for model properties are supported.",
                                        expression.Body.NodeType),
                         ex.Message);
        }

        [Fact]
        public void GetPropertyName_FieldExpression_Throws()
        {
            // Arrange
            Expression<Func<User, object>> expression = m => m._userId;

            // Act & Assert
            var ex = Assert.Throws<InvalidOperationException>(() =>
                        ModelBindingHelper.GetPropertyName(expression.Body));

            Assert.Equal(string.Format("The passed expression of expression node type '{0}' is invalid." +
                                       " Only simple member access expressions for model properties are supported.",
                                        expression.Body.NodeType),
                         ex.Message);
        }

        [Fact]
        public async Task TryUpdateModelNonGeneric_PredicateOverload_ReturnsFalse_IfBinderReturnsNull()
        {
            // Arrange
            var metadataProvider = new EmptyModelMetadataProvider();
            var binder = new Mock<IModelBinder>();
            binder.Setup(b => b.BindModelAsync(It.IsAny<ModelBindingContext>()))
                  .Returns(Task.FromResult<ModelBindingResult>(null));
            var model = new MyModel();
            Func<ModelBindingContext, string, bool> includePredicate =
               (context, propertyName) => true;
            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                                                    model,
                                                    model.GetType(),
                                                    prefix: null,
                                                    httpContext: Mock.Of<HttpContext>(),
                                                    modelState: new ModelStateDictionary(),
                                                    metadataProvider: metadataProvider,
                                                    modelBinder: GetCompositeBinder(binder.Object),
                                                    valueProvider: Mock.Of<IValueProvider>(),
                                                    inputFormatters: new List<IInputFormatter>(),
                                                    objectModelValidator: Mock.Of<IObjectModelValidator>(),
                                                    validatorProvider: Mock.Of<IModelValidatorProvider>(),
                                                    predicate: includePredicate);

            // Assert
            Assert.False(result);
            Assert.Null(model.MyProperty);
            Assert.Null(model.IncludedProperty);
            Assert.Null(model.ExcludedProperty);
        }

        [Fact]
        public async Task TryUpdateModelNonGeneric_PredicateOverload_ReturnsTrue_ModelBindsAndValidatesSuccessfully()
        {
            // Arrange
            var binders = new IModelBinder[]
            {
                new TypeConverterModelBinder(),
                new ComplexModelDtoModelBinder(),
                new MutableObjectModelBinder()
            };

            var validator = new DataAnnotationsModelValidatorProvider();
            var model = new MyModel
            {
                MyProperty = "Old-Value",
                IncludedProperty = "Old-IncludedPropertyValue",
                ExcludedProperty = "Old-ExcludedPropertyValue"
            };

            var modelStateDictionary = new ModelStateDictionary();
            var values = new Dictionary<string, object>
            {
                { "", null },
                { "MyProperty", "MyPropertyValue" },
                { "IncludedProperty", "IncludedPropertyValue" },
                { "ExcludedProperty", "ExcludedPropertyValue" }
            };

            Func<ModelBindingContext, string, bool> includePredicate =
                (context, propertyName) =>
                                string.Equals(propertyName, "IncludedProperty", StringComparison.OrdinalIgnoreCase) ||
                                string.Equals(propertyName, "MyProperty", StringComparison.OrdinalIgnoreCase);

            var valueProvider = new TestValueProvider(values);
            var metadataProvider = TestModelMetadataProvider.CreateDefaultProvider();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                                                    model,
                                                    model.GetType(),
                                                    "",
                                                    Mock.Of<HttpContext>(),
                                                    modelStateDictionary,
                                                    metadataProvider,
                                                    GetCompositeBinder(binders),
                                                    valueProvider,
                                                    new List<IInputFormatter>(),
                                                    new DefaultObjectValidator(
                                                        new IExcludeTypeValidationFilter[0],
                                                        metadataProvider),
                                                    validator,
                                                    includePredicate);

            // Assert
            Assert.True(result);
            Assert.Equal("MyPropertyValue", model.MyProperty);
            Assert.Equal("IncludedPropertyValue", model.IncludedProperty);
            Assert.Equal("Old-ExcludedPropertyValue", model.ExcludedProperty);
        }

        [Fact]
        public async Task TryUpdateModelNonGeneric_ModelTypeOverload_ReturnsFalse_IfBinderReturnsNull()
        {
            // Arrange
            var metadataProvider = new EmptyModelMetadataProvider();

            var binder = new Mock<IModelBinder>();
            binder.Setup(b => b.BindModelAsync(It.IsAny<ModelBindingContext>()))
                  .Returns(Task.FromResult<ModelBindingResult>(null));
            var model = new MyModel();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                                                    model,
                                                    modelType: model.GetType(),
                                                    prefix: null,
                                                    httpContext: Mock.Of<HttpContext>(),
                                                    modelState: new ModelStateDictionary(),
                                                    metadataProvider: metadataProvider,
                                                    modelBinder: GetCompositeBinder(binder.Object),
                                                    valueProvider: Mock.Of<IValueProvider>(),
                                                    inputFormatters: new List<IInputFormatter>(),
                                                    objectModelValidator: Mock.Of<IObjectModelValidator>(),
                                                    validatorProvider: Mock.Of<IModelValidatorProvider>());

            // Assert
            Assert.False(result);
            Assert.Null(model.MyProperty);
        }

        [Fact]
        public async Task TryUpdateModelNonGeneric_ModelTypeOverload_ReturnsTrue_IfModelBindsAndValidatesSuccessfully()
        {
            // Arrange
            var binders = new IModelBinder[]
            {
                new TypeConverterModelBinder(),
                new ComplexModelDtoModelBinder(),
                new MutableObjectModelBinder()
            };

            var validator = new DataAnnotationsModelValidatorProvider();
            var model = new MyModel { MyProperty = "Old-Value" };
            var modelStateDictionary = new ModelStateDictionary();
            var values = new Dictionary<string, object>
            {
                { "", null },
                { "MyProperty", "MyPropertyValue" }
            };
            var valueProvider = new TestValueProvider(values);
            var metadataProvider = TestModelMetadataProvider.CreateDefaultProvider();

            // Act
            var result = await ModelBindingHelper.TryUpdateModelAsync(
                                                    model,
                                                    model.GetType(),
                                                    "",
                                                    Mock.Of<HttpContext>(),
                                                    modelStateDictionary,
                                                    TestModelMetadataProvider.CreateDefaultProvider(),
                                                    GetCompositeBinder(binders),
                                                    valueProvider,
                                                    new List<IInputFormatter>(),
                                                    new DefaultObjectValidator(
                                                        new IExcludeTypeValidationFilter[0],
                                                        metadataProvider),
                                                    validator);

            // Assert
            Assert.True(result);
            Assert.Equal("MyPropertyValue", model.MyProperty);
        }

        [Fact]
        public async Task TryUpdataModel_ModelTypeDifferentFromModel_Throws()
        {
            // Arrange
            var metadataProvider = new EmptyModelMetadataProvider();

            var binder = new Mock<IModelBinder>();
            binder.Setup(b => b.BindModelAsync(It.IsAny<ModelBindingContext>()))
                  .Returns(Task.FromResult<ModelBindingResult>(null));
            var model = new MyModel();
            Func<ModelBindingContext, string, bool> includePredicate =
               (context, propertyName) => true;

            // Act & Assert
            var exception = await Assert.ThrowsAsync<ArgumentException>(
                () => ModelBindingHelper.TryUpdateModelAsync(
                                                    model,
                                                    typeof(User),
                                                    null,
                                                    Mock.Of<HttpContext>(),
                                                    new ModelStateDictionary(),
                                                    metadataProvider,
                                                    GetCompositeBinder(binder.Object),
                                                    Mock.Of<IValueProvider>(),
                                                    new List<IInputFormatter>(),
                                                    new DefaultObjectValidator(
                                                        new IExcludeTypeValidationFilter[0],
                                                        metadataProvider),
                                                    Mock.Of<IModelValidatorProvider>(),
                                                    includePredicate));

            var expectedMessage = string.Format("The model's runtime type '{0}' is not assignable to the type '{1}'." +
                Environment.NewLine +
                "Parameter name: modelType",
                model.GetType().FullName,
                typeof(User).FullName);
            Assert.Equal(expectedMessage, exception.Message);
        }

        [Theory]
        [InlineData("")]
        [InlineData(null)]
        public void ClearValidationStateForModel_EmtpyModelKey(string modelKey)
        {
            // Arrange
            var metadataProvider = new EmptyModelMetadataProvider();
            var dictionary = new ModelStateDictionary();
            dictionary["Name"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("Name", "MyProperty invalid.");
            dictionary["Id"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("Id", "Id invalid.");
            dictionary.AddModelError("Id", "Id is required.");
            dictionary["Category"] = new ModelState { ValidationState = ModelValidationState.Valid };

            // Act
            ModelBindingHelper.ClearValidationStateForModel(
                typeof(Product),
                dictionary,
                metadataProvider,
                modelKey);

            // Assert
            Assert.Equal(0, dictionary["Name"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["Name"].ValidationState);
            Assert.Equal(0, dictionary["Id"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["Id"].ValidationState);
            Assert.Equal(0, dictionary["Category"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["Category"].ValidationState);
        }

        [Theory]
        [InlineData("")]
        [InlineData(null)]
        public void ClearValidationStateForCollectionsModel_EmtpyModelKey(string modelKey)
        {
            // Arrange
            var metadataProvider = new EmptyModelMetadataProvider();
            var dictionary = new ModelStateDictionary();
            dictionary["[0].Name"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("[0].Name", "Name invalid.");
            dictionary["[0].Id"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("[0].Id", "Id invalid.");
            dictionary.AddModelError("[0].Id", "Id required.");
            dictionary["[0].Category"] = new ModelState { ValidationState = ModelValidationState.Valid };

            dictionary["[1].Name"] = new ModelState { ValidationState = ModelValidationState.Valid };
            dictionary["[1].Id"] = new ModelState { ValidationState = ModelValidationState.Valid };
            dictionary["[1].Category"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("[1].Category", "Category invalid.");

            // Act
            ModelBindingHelper.ClearValidationStateForModel(
                typeof(List<Product>),
                dictionary,
                metadataProvider,
                modelKey);

            // Assert
            Assert.Equal(0, dictionary["[0].Name"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["[0].Name"].ValidationState);
            Assert.Equal(0, dictionary["[0].Id"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["[0].Id"].ValidationState);
            Assert.Equal(0, dictionary["[0].Category"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["[0].Category"].ValidationState);
            Assert.Equal(0, dictionary["[1].Name"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["[1].Name"].ValidationState);
            Assert.Equal(0, dictionary["[1].Id"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["[1].Id"].ValidationState);
            Assert.Equal(0, dictionary["[1].Category"].Errors.Count);
            Assert.Equal(ModelValidationState.Unvalidated, dictionary["[1].Category"].ValidationState);
        }

        [Theory]
        [InlineData("product")]
        [InlineData("product.Name")]
        [InlineData("product.Order[0].Name")]
        [InlineData("product.Order[0].Address.Street")]
        [InlineData("product.Category.Name")]
        [InlineData("product.Order")]
        public void ClearValidationStateForModel_NonEmtpyModelKey(string prefix)
        {
            // Arrange
            var metadataProvider = new TestModelMetadataProvider();

            var dictionary = new ModelStateDictionary();
            dictionary["product.Name"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("product.Name", "Name invalid.");
            dictionary["product.Id"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("product.Id", "Id invalid.");
            dictionary.AddModelError("product.Id", "Id required.");
            dictionary["product.Category"] = new ModelState { ValidationState = ModelValidationState.Valid };
            dictionary["product.Category.Name"] = new ModelState { ValidationState = ModelValidationState.Valid };
            dictionary["product.Order[0].Name"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("product.Order[0].Name", "Order name invalid.");
            dictionary["product.Order[0].Address.Street"] =
                new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("product.Order[0].Address.Street", "Street invalid.");
            dictionary["product.Order[1].Name"] = new ModelState { ValidationState = ModelValidationState.Valid };
            dictionary["product.Order[0]"] = new ModelState { ValidationState = ModelValidationState.Invalid };
            dictionary.AddModelError("product.Order[0]", "Order invalid.");

            // Act
            ModelBindingHelper.ClearValidationStateForModel(
                typeof(Product),
                dictionary,
                metadataProvider,
                prefix);

            // Assert
            foreach (var entry in dictionary.Keys)
            {
                if (entry.StartsWith(prefix))
                {
                    Assert.Equal(0, dictionary[entry].Errors.Count);
                    Assert.Equal(ModelValidationState.Unvalidated, dictionary[entry].ValidationState);
                }
            }
        }

        private static IModelBinder GetCompositeBinder(params IModelBinder[] binders)
        {
            return new CompositeModelBinder(binders);
        }

        public class User
        {
            public string _userId;

            public Address Address { get; set; }

            public User[] Friends { get; set; }

            public List<User> Colleagues { get; set; }

            public bool IsReadOnly
            {
                get
                {
                    throw new NotImplementedException();
                }
            }

            public User Save()
            {
                return this;
            }
        }

        public class Address
        {
            public string Street { get; set; }
        }

        private class MyModel
        {
            [Required]
            public string MyProperty { get; set; }

            public string IncludedProperty { get; set; }

            public string ExcludedProperty { get; set; }
        }

        private class Product
        {
            public string Name { get; set; }
            public int Id { get; set; }
            public Category Category { get; set; }
            public List<Order> Orders { get; set; }
        }

        public class Category
        {
            public string Name { get; set; }
        }

        public class Order
        {
            public string Name { get; set; }
            public Address Address { get; set; }
        }
    }
}
#endif