/src/NHibernate.Spatial/src/NHibernate.Spatial/Linq/Functions/SpatialPropertyGenerator.cs

using System;

using System.Linq;

using System.Linq.Expressions;

using System.Reflection;

using GeoAPI.Geometries;

using NHibernate.Hql.Ast;

using NHibernate.Linq;

using NHibernate.Linq.Functions;

using NHibernate.Linq.Visitors;

using NHibernate.Spatial.Dialect;



namespace NHibernate.Spatial.Linq.Functions

{

	public abstract class SpatialPropertyGenerator<TGeometry, TResult> : BaseHqlGeneratorForProperty

		where TGeometry : IGeometry

	{

		protected SpatialPropertyGenerator(params Expression<Func<TGeometry, TResult>>[] expressions)

		{

			SupportedProperties = expressions.Select(o => ReflectionHelper.GetProperty(o)).ToArray();

		}



		public override HqlTreeNode BuildHql(MemberInfo member, Expression expression, HqlTreeBuilder treeBuilder, IHqlExpressionVisitor visitor)

		{

			var methodCall = treeBuilder.MethodCall(SpatialDialect.HqlPrefix + member.Name, new[]

			{

				visitor.Visit(expression).AsExpression()

			});

			if (typeof(TResult) == typeof(bool))

			{

				return treeBuilder.Equality(methodCall, treeBuilder.True());

			}

			return methodCall;

		}

	}



}