Strongly typed AppSettings with Genuilder.Extensibility

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Genuilder.Extensibility;
using System.Configuration;
using ICSharpCode.NRefactory.Ast;
using ICSharpCode.NRefactory;
using ICSharpCode.NRefactory.Visitors;

namespace StronglyTypedAppSettingsPlugin2.Gen
{
	public class StronglyTypedAppSettingsPlugin : IPlugin
	{
		#region IPlugin Members

		public void Initialize(ICodeRepository repository)
		{
			repository.CodeItemCreated += new CodeItemCreatedHandler(repository_CodeItemCreated);
		}

		void repository_CodeItemCreated(ICodeRepository sender, CodeItem item)
		{
			if(item.Name.EndsWith(".config"))
			{
				var dependency = item.SourceOf("StronglyTypedSettings.cs");
				dependency.ShouldUpdateTarget += new CodeDependencyHandler(dependency_ShouldUpdateTarget);
			}
		}

		void dependency_ShouldUpdateTarget(CodeDependency sender, CodeItem target)
		{
			var configuration = ConfigurationManager.OpenMappedExeConfiguration(new ExeConfigurationFileMap()
			{
				ExeConfigFilename = ((FileCodeItem)sender.Source).File.FullName
			}, ConfigurationUserLevel.None);


			var targetNRefactoryExtension = target.GetExtension<Genuilder.Extensibility.NRefactory.CompilationUnitExtension>();

			targetNRefactoryExtension.CompilationUnit.Children.Clear();
			var typeDeclaration = new TypeDeclaration(Modifiers.Public | Modifiers.Static, null)
			{
				Name = "AppConfigSettings"
			};
			targetNRefactoryExtension.CompilationUnit.Children.Add(typeDeclaration);



			foreach(KeyValueConfigurationElement setting in configuration.AppSettings.Settings)
			{

				var propertyDeclaration = new PropertyDeclaration(Modifiers.Public | Modifiers.Static, null, setting.Key, null)
				{
					TypeReference = new TypeReference(typeof(String).FullName)
				};
				var indexer = new IndexerExpression(
					new MemberReferenceExpression(
						new TypeReferenceExpression(
							new TypeReference(typeof(ConfigurationManager).FullName)), "AppSettings")
								, new List<Expression>()
						{
							new ICSharpCode.NRefactory.Ast.PrimitiveExpression(setting.Key)
						});

				propertyDeclaration.GetRegion = new PropertyGetRegion(new BlockStatement(), null);
				propertyDeclaration.GetRegion.Block.Children.Add(new ReturnStatement(indexer));
				typeDeclaration.Children.Add(propertyDeclaration);

			}
			targetNRefactoryExtension.Save();
			target.Logger.Send("Settings generated !!", Genuilder.Extensibility.Utilities.LogType.Warning);
		}

		#endregion
	}
}