// Copyright (C) 2003-2010 Xtensive LLC.

// All rights reserved.

// For conditions of distribution and use, see license.

// Created by: Alexis Kochetov

// Created:    2009.05.26



using System;

using System.Diagnostics;

using System.Linq.Expressions;



namespace Xtensive.Storage.Linq.Expressions.Visitors

{

  internal class OwnerRemover : PersistentExpressionVisitor

  {

    public static Expression RemoveOwner(Expression target)

    {

      var remover = new OwnerRemover();

      return remover.Visit(target);

    }



    protected override Expression VisitGroupingExpression(GroupingExpression expression)

    {

      return expression;

    }



    protected override Expression VisitSubQueryExpression(SubQueryExpression expression)

    {

      return expression;

    }



    protected override Expression VisitFieldExpression(FieldExpression expression)

    {

      return expression.RemoveOwner();

    }



    protected override Expression VisitStructureFieldExpression(StructureFieldExpression expression)

    {

      return expression.RemoveOwner();

    }



    protected override Expression VisitKeyExpression(KeyExpression expression)

    {

      return expression;

    }



    protected override Expression VisitEntityExpression(EntityExpression expression)

    {

      return expression;

    }



    protected override Expression VisitEntityFieldExpression(EntityFieldExpression expression)

    {

      return expression.RemoveOwner();

    }



    protected override Expression VisitEntitySetExpression(EntitySetExpression expression)

    {

      return expression;

    }



    protected override Expression VisitColumnExpression(ColumnExpression expression)

    {

      return expression;

    }

  }

}