using System;
using System.Xml;

namespace oodb.mapping
{
    public class ReferenceMapping : NaiveMapping
    {
        public ReferenceMapping(OODB oodb, Type type)
            : base(oodb, type)
        {
        }

        public override object FromText(string text)
        {
            if (String.Empty.Equals(text))
                return null;
            
            Guid persistenceID = Guid.Parse(text);
            return OODB.Load(NativeType, persistenceID);
        }
        public override string ToText(object value)
        {
            Persistent reference = value as Persistent;

            if (reference == null)
            {
                return Guid.Empty.ToString();
            }
            else
            {
                string text = reference.PersistenceID.ToString();
                OODB.Ensure(reference);
                return text;
            }
        }
    }
}