//---------------------------------------------------------------------
// <copyright file="ProxyDataContractResolver.cs" company="Microsoft">
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>
//
// @owner       [....]
// @backupOwner [....]
//---------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Runtime.Serialization;

namespace System.Data.Objects
{
    /// <summary>
    /// A DataContractResolver that knows how to resolve proxy types created for persistent
    /// ignorant classes to their base types. This is used with the DataContractSerializer.
    /// </summary>
    public class ProxyDataContractResolver : DataContractResolver
    {
        private XsdDataContractExporter _exporter = new XsdDataContractExporter();
        
        public override Type ResolveName(string typeName, string typeNamespace, Type declaredType, DataContractResolver knownTypeResolver)
        {
            EntityUtil.CheckStringArgument(typeName, "typeName");
            EntityUtil.CheckStringArgument(typeNamespace, "typeNamespace");
            EntityUtil.CheckArgumentNull(declaredType, "declaredType");
            EntityUtil.CheckArgumentNull(knownTypeResolver, "knownTypeResolver");

            return knownTypeResolver.ResolveName(typeName, typeNamespace, declaredType ,null);
        }

        public override bool TryResolveType(Type dataContractType, Type declaredType, DataContractResolver knownTypeResolver, out System.Xml.XmlDictionaryString typeName, out System.Xml.XmlDictionaryString typeNamespace)
        {
            EntityUtil.CheckArgumentNull(dataContractType, "dataContractType");
            EntityUtil.CheckArgumentNull(declaredType, "declaredType");
            EntityUtil.CheckArgumentNull(knownTypeResolver, "knownTypeResolver");

            Type nonProxyType = ObjectContext.GetObjectType(dataContractType);
            if (nonProxyType != dataContractType)
            {
                // Type was a proxy type, so map the name to the non-proxy name
                XmlQualifiedName qualifiedName = _exporter.GetSchemaTypeName(nonProxyType);
                XmlDictionary dictionary = new XmlDictionary(2);
                typeName = new XmlDictionaryString(dictionary, qualifiedName.Name, 0);
                typeNamespace = new XmlDictionaryString(dictionary, qualifiedName.Namespace, 1);
                return true;
            }
            else 
            {
                // Type was not a proxy type, so do the default
                return knownTypeResolver.TryResolveType(dataContractType, declaredType, null, out typeName, out typeNamespace);
            } 
        }
    }
}