/// <summary>
        /// Initializes a new instance of the <see cref="SelectExpandQueryOption"/> class.
        /// </summary>
        /// <param name="select">The $select query parameter value.</param>
        /// <param name="expand">The $expand query parameter value.</param>
        /// <param name="context">The <see cref="ODataQueryContext"/> which contains the <see cref="IEdmModel"/> and some type information.</param>
        /// <param name="queryOptionParser">The <see cref="ODataQueryOptionParser"/> which is used to parse the query option.</param>
        public SelectExpandQueryOption(string select, string expand, ODataQueryContext context,
            ODataQueryOptionParser queryOptionParser)
        {
            if (context == null)
            {
                throw Error.ArgumentNull("context");
            }

            if (String.IsNullOrEmpty(select) && String.IsNullOrEmpty(expand))
            {
                throw Error.Argument(SRResources.SelectExpandEmptyOrNull);
            }

            if (queryOptionParser == null)
            {
                throw Error.ArgumentNull("queryOptionParser");
            }

            IEdmEntityType entityType = context.ElementType as IEdmEntityType;
            if (entityType == null)
            {
                throw Error.Argument("context", SRResources.SelectNonEntity, context.ElementType.ToTraceString());
            }

            Context = context;
            RawSelect = select;
            RawExpand = expand;
            Validator = new SelectExpandQueryValidator();
            _queryOptionParser = queryOptionParser;
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="ODataQueryOptions"/> class based on the incoming request and some metadata information from 
        /// the <see cref="ODataQueryContext"/>.
        /// </summary>
        /// <param name="context">The <see cref="ODataQueryContext"/> which contains the <see cref="IEdmModel"/> and some type information</param>
        /// <param name="request">The incoming request message</param>
        public ODataQueryOptions(ODataQueryContext context, HttpRequestMessage request)
        {
            if (context == null)
            {
                throw Error.ArgumentNull("context");
            }

            if (request == null)
            {
                throw Error.ArgumentNull("request");
            }

            // remember the context
            Context = context;

            // Parse the query from request Uri
            RawValues = new ODataRawQueryOptions();
            IEnumerable<KeyValuePair<string, string>> queryParameters = request.GetQueryNameValuePairs();
            foreach (KeyValuePair<string, string> kvp in queryParameters)
            {
                switch (kvp.Key)
                {
                    case "$filter":
                        RawValues.Filter = kvp.Value;
                        ThrowIfEmpty(kvp.Value, "$filter");
                        Filter = new FilterQueryOption(kvp.Value, context);
                        break;
                    case "$orderby":
                        RawValues.OrderBy = kvp.Value;
                        ThrowIfEmpty(kvp.Value, "$orderby");
                        OrderBy = new OrderByQueryOption(kvp.Value, context);
                        break;
                    case "$top":
                        RawValues.Top = kvp.Value;
                        ThrowIfEmpty(kvp.Value, "$top");
                        Top = new TopQueryOption(kvp.Value, context);
                        break;
                    case "$skip":
                        RawValues.Skip = kvp.Value;
                        ThrowIfEmpty(kvp.Value, "$skip");
                        Skip = new SkipQueryOption(kvp.Value, context);
                        break;
                    case "$select":
                        RawValues.Select = kvp.Value;
                        break;
                    case "$inlinecount":
                        RawValues.InlineCount = kvp.Value;
                        break;
                    case "$expand":
                        RawValues.Expand = kvp.Value;
                        break;
                    case "$skiptoken":
                        RawValues.SkipToken = kvp.Value;
                        break;
                    default:
                        // we don't throw if we can't recognize the query
                        break;
                }
            }
        }

        public void Validate_DepthChecks_DollarLevels(string expand, int maxExpansionDepth)
        {
            // Arrange
            var validator = new SelectExpandQueryValidator();
            var builder = new ODataConventionModelBuilder();
            builder.EntitySet<ODataLevelsTest.LevelsEntity>("Entities");
            IEdmModel model = builder.GetEdmModel();
            var context = new ODataQueryContext(model, typeof(ODataLevelsTest.LevelsEntity));
            var selectExpandQueryOption = new SelectExpandQueryOption(null, expand, context);
            selectExpandQueryOption.LevelsMaxLiteralExpansionDepth = 1;

            // Act & Assert
            Assert.Throws<ODataException>(
                () => validator.Validate(
                    selectExpandQueryOption,
                    new ODataValidationSettings { MaxExpansionDepth = maxExpansionDepth }),
                String.Format(
                    CultureInfo.CurrentCulture,
                    "The request includes a $expand path which is too deep. The maximum depth allowed is {0}. " +
                    "To increase the limit, set the 'MaxExpansionDepth' property on EnableQueryAttribute or ODataValidationSettings.",
                    maxExpansionDepth));

            Assert.DoesNotThrow(
                () => validator.Validate(
                    selectExpandQueryOption,
                    new ODataValidationSettings { MaxExpansionDepth = maxExpansionDepth + 1 }));
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="ODataQueryOptions"/> class based on the incoming request and some metadata information from
        /// the <see cref="ODataQueryContext"/>.
        /// </summary>
        /// <param name="context">The <see cref="ODataQueryContext"/> which contains the <see cref="IEdmModel"/> and some type information.</param>
        /// <param name="request">The incoming request message.</param>
        public ODataQueryOptions(ODataQueryContext context, HttpRequest request)
        {
            if (context == null)
            {
                throw Error.ArgumentNull("context");
            }

            if (request == null)
            {
                throw Error.ArgumentNull("request");
            }

            _assemblyProvider = request.AssemblyProvider();

            Context = context;
            Request = request;
            RawValues = new ODataRawQueryOptions();

            var queryOptionDict = request.Query.ToDictionary(p => p.Key, p => p.Value.FirstOrDefault());
            _queryOptionParser = new ODataQueryOptionParser(
                context.Model,
                context.ElementType,
                context.NavigationSource,
                queryOptionDict);
            
            BuildQueryOptions(queryOptionDict);
        }

        public void Constructor_TakingClrType_WithPrimitiveTypes(Type type)
        {
            // Arrange & Act
            ODataQueryContext context = new ODataQueryContext(EdmCoreModel.Instance, type);

            // Assert
            Assert.True(context.ElementClrType == type);
        }

        public void Value_Returns_ParsedSkipValue(string skipValue, int expectedValue)
        {
            var model = new ODataModelBuilder().Add_Customer_EntityType().Add_Customers_EntitySet().GetEdmModel();
            var context = new ODataQueryContext(model, typeof(Customer));
            var skip = new SkipQueryOption(skipValue, context);

            Assert.Equal(expectedValue, skip.Value);
        }

 public ODataQueryValidatorTest()
 {
     _validator = new ODataQueryValidator();
     _builder = new ODataConventionModelBuilder();
     _builder.EntitySet<QueryCompositionCustomer>("Customer");
     _model = _builder.GetEdmModel();
     _context = new ODataQueryContext(_model, typeof(QueryCompositionCustomer));
 }

		public virtual object ApplyQueryOptions(object value, HttpRequest request, ActionDescriptor actionDescriptor, AssembliesResolver assembliesResolver)
		{
			var elementClrType = value is IEnumerable
				? TypeHelper.GetImplementedIEnumerableType(value.GetType())
				: value.GetType();

			var model = request.ODataProperties().Model;
			if (model == null)
			{
				throw Error.InvalidOperation(SRResources.QueryGetModelMustNotReturnNull);
			}

			var queryContext = new ODataQueryContext(
				model,
				elementClrType,
				assembliesResolver,
				request.ODataProperties().Path
				);

			var queryOptions = new ODataQueryOptions(queryContext, request, assembliesResolver);

			var enumerable = value as IEnumerable;
			if (enumerable == null)
			{
				// response is single entity.
				return value;
			}

			// response is a collection.
			var query = (value as IQueryable) ?? enumerable.AsQueryable();

			query = queryOptions.ApplyTo(query,
				new ODataQuerySettings
				{
					// TODO: If we are using SQL, set this to false
					// otherwise if it is entities in code then
					// set it to true
					HandleNullPropagation = 
					//HandleNullPropagationOption.True
					HandleNullPropagationOptionHelper.GetDefaultHandleNullPropagationOption(query),
					PageSize = actionDescriptor.PageSize(),
					SearchDerivedTypeWhenAutoExpand = true
				},
				AllowedQueryOptions.None);
			// Determine if this result should be a single entity
			
			if (ODataCountMediaTypeMapping.IsCountRequest(request))
			{
				long? count = request.ODataProperties().TotalCount;

				if (count.HasValue)
				{
					// Return the count value if it is a $count request.
					return count.Value;
				}
			}
			return query;
		}

        public void Ctor_ThrowsArgument_IfContextIsNotForAnEntityType()
        {
            ODataQueryContext context = new ODataQueryContext(_model.Model, typeof(int));

            Assert.ThrowsArgument(
                () => new SelectExpandQueryOption(select: "Name", expand: "Name", context: context),
                "context",
                "The type 'Edm.Int32' is not an entity type. Only entity types support $select and $expand.");
        }

        public void CanConstructValidFilterQuery(string orderbyValue)
        {
            var model = new ODataModelBuilder().Add_Customer_EntityType().Add_Customers_EntitySet().GetEdmModel();
            var context = new ODataQueryContext(model, typeof(Customer));
            var orderby = new OrderByQueryOption(orderbyValue, context);

            Assert.Same(context, orderby.Context);
            Assert.Equal(orderbyValue, orderby.RawValue);
        }

        public void ApplyInValidOrderbyQueryThrows(string orderbyValue)
        {
            var model = new ODataModelBuilder().Add_Customer_EntityType().Add_Customers_EntitySet().GetEdmModel();
            var context = new ODataQueryContext(model, typeof(Customer));
            var orderby = new OrderByQueryOption(orderbyValue, context);

            Assert.Throws<ODataException>(() =>
                orderby.ApplyTo(ODataQueryOptionTest.Customers));
        }

        public void CanConstructValidFilterQuery(string filterValue)
        {
            var model = new ODataModelBuilder().Add_Customer_EntityType().Add_Customers_EntitySet().GetEdmModel();
            var context = new ODataQueryContext(model, typeof(Customer), "Customers");
            var filter = new FilterQueryOption(filterValue, context);

            Assert.Same(context, filter.Context);
            Assert.Equal(filterValue, filter.RawValue);
        }

        public void CanConstructValidFilterQuery(string skipValue)
        {
            var model = new ODataModelBuilder().Add_Customer_EntityType().Add_Customers_EntitySet().GetEdmModel();
            var context = new ODataQueryContext(model, typeof(Customer));
            var skip = new SkipQueryOption(skipValue, context);

            Assert.Same(context, skip.Context);
            Assert.Equal(skipValue, skip.RawValue);
        }

        public void ApplyInValidSkipQueryThrows(string skipValue)
        {
            var model = new ODataModelBuilder().Add_Customer_EntityType().Add_Customers_EntitySet().GetEdmModel();
            var context = new ODataQueryContext(model, typeof(Customer));
            var skip = new SkipQueryOption(skipValue, context);

            Assert.Throws<ODataException>(() =>
                skip.ApplyTo(ODataQueryOptionTest.Customers));
        }

        public void Ctor_ThrowsArgument_IfBothSelectAndExpandAreNull()
        {
            _model.Model.SetAnnotationValue<ClrTypeAnnotation>(_model.Customer, new ClrTypeAnnotation(typeof(Customer)));
            ODataQueryContext context = new ODataQueryContext(_model.Model, typeof(Customer));

            Assert.Throws<ArgumentException>(
                () => new SelectExpandQueryOption(select: null, expand: null, context: context),
                "'select' and 'expand' cannot be both null or empty.");
        }

        public void Ctor_SuccedsIfEntityTypesMatch()
        {
            ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
            builder.EntitySet<Customer>("Customers");

            ODataQueryContext context = new ODataQueryContext(builder.GetEdmModel(), typeof(Customer));

            ODataQueryOptions<Customer> query = new ODataQueryOptions<Customer>(context, new HttpRequestMessage(HttpMethod.Get, "http://server/?$top=10"));
            Assert.Equal("10", query.Top.RawValue);
        }

        public void Ctor_ThrowsArgumentNull_QueryOptionParser()
        {
            // Arrange
            ODataQueryContext context = new ODataQueryContext(_model.Model, typeof(int));

            // Act & Assert
            Assert.ThrowsArgumentNull(
                () => new SelectExpandQueryOption("select", "expand", context, queryOptionParser: null),
                "queryOptionParser");
        }

        public void Ctor_Throws_Argument_IfContextIsUnTyped()
        {
            IEdmModel model = EdmCoreModel.Instance;
            IEdmType elementType = EdmCoreModel.Instance.GetPrimitiveType(EdmPrimitiveTypeKind.Int32);
            ODataQueryContext context = new ODataQueryContext(model, elementType);

            Assert.ThrowsArgument(
                () => new ODataQueryOptions<int>(context, new HttpRequestMessage()),
                "context", "The property 'ElementClrType' of ODataQueryContext cannot be null.");
        }

        public void Ctor_Throws_Argument_IfContextIsofDifferentEntityType()
        {
            ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
            builder.EntitySet<Customer>("Customers");

            ODataQueryContext context = new ODataQueryContext(builder.GetEdmModel(), typeof(Customer));

            Assert.ThrowsArgument(
                () => new ODataQueryOptions<int>(context, new HttpRequestMessage()),
                "context", "The entity type 'System.Web.OData.TestCommon.Models.Customer' does not match the expected entity type 'System.Int32' as set on the query context.");
        }

        public void ContructorWithOnlyType(Type type)
        {
            // Arrange & Act
            ODataQueryContext context = new ODataQueryContext(type);

            // Assert
            Assert.Null(context.Model);
            Assert.True(context.EntityClrType == type);
            Assert.Null(context.EntitySet);
            Assert.True(context.IsPrimitiveClrType);
        }