--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Agendas/trunk/src/Agendas.NHibernate/GenericWellKnownInstanceType.cs	Fri Jul 29 16:30:53 2011 -0300
@@ -0,0 +1,114 @@
+using System;
+using System.Collections.Generic;
+using System.Data;
+using System.Linq;
+using NHibernate.SqlTypes;
+using NHibernate.UserTypes;
+
+namespace Agendas.NHibernate
+{
+	[Serializable]
+	public abstract class GenericWellKnownInstanceType<T, TId> : IUserType where T : class
+	{
+		//private static readonly SqlType[] ReturnSqlTypes = { SqlTypeFactory.Int32 };
+		private Func<T, TId, bool> findPredicate;
+		private Func<T, TId> idGetter;
+		private IEnumerable<T> repository;
+
+		/// <summary>
+		/// Base constructor
+		/// </summary>
+		/// <param name="repository">The collection that represent a in-memory repository.</param>
+		/// <param name="findPredicate">The predicate an instance by the persisted value.</param>
+		/// <param name="idGetter">The getter of the persisted value.</param>
+		protected GenericWellKnownInstanceType(IEnumerable<T> repository, Func<T, TId, bool> findPredicate, Func<T, TId> idGetter)
+		{
+			this.repository = repository;
+			this.findPredicate = findPredicate;
+			this.idGetter = idGetter;
+		}
+
+		//public SqlType[] SqlTypes
+		//{
+		//    get { return ReturnSqlTypes; }
+		//}
+
+		public Type ReturnedType
+		{
+			get { return typeof(T); }
+		}
+
+		public bool IsMutable
+		{
+			get { return false; }
+		}
+
+		public new bool Equals(object x, object y)
+		{
+			if (ReferenceEquals(x, y))
+			{
+				return true;
+			}
+			if (ReferenceEquals(null, x) || ReferenceEquals(null, y))
+			{
+				return false;
+			}
+
+			return x.Equals(y);
+		}
+
+		public int GetHashCode(object x)
+		{
+			return (x == null) ? 0 : x.GetHashCode();
+		}
+
+		public object NullSafeGet(IDataReader rs, string[] names, object owner)
+		{
+			int index0 = rs.GetOrdinal(names[0]);
+			if (rs.IsDBNull(index0))
+			{
+				return null;
+			}
+
+			var value = (TId)rs.GetValue(index0);
+			return repository.FirstOrDefault(x => findPredicate(x, value));
+		}
+
+		public void NullSafeSet(IDbCommand cmd, object value, int index)
+		{
+			if (value == null)
+			{
+				((IDbDataParameter)cmd.Parameters[index]).Value = DBNull.Value;
+			}
+			else
+			{
+				((IDbDataParameter)cmd.Parameters[index]).Value = idGetter((T)value);
+			}
+		}
+
+		public object DeepCopy(object value)
+		{
+			return value;
+		}
+
+		public object Replace(object original, object target, object owner)
+		{
+			return original;
+		}
+
+		public object Assemble(object cached, object owner)
+		{
+			return cached;
+		}
+
+		public object Disassemble(object value)
+		{
+			return value;
+		}
+
+		/// <summary>
+		/// The SQL types for the columns mapped by this type. 
+		/// </summary>
+		public abstract SqlType[] SqlTypes { get; }
+	}
+}
\ No newline at end of file