source: branches/CodeEditor/HeuristicLab.ExtLibs/HeuristicLab.NRefactory/5.5.0/NRefactory.CSharp-5.5.0/Refactoring/CodeActions/RemoveFieldRefactoryActionRefactoringAction.cs @ 11700

//
// RemoveField.cs
//
// Author:
//       Ciprian Khlud <ciprian.mustiata@yahoo.com>
//
// Copyright (c) 2013 Ciprian Khlud
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
using System;
using ICSharpCode.NRefactory.CSharp.Refactoring;
using System.Collections.Generic;
using ICSharpCode.NRefactory.CSharp.Resolver;
using ICSharpCode.NRefactory.Semantics;

namespace ICSharpCode.NRefactory.CSharp
{
//  [ContextAction("Removes a field from a class", Description = "It removes also the empty assingments and the usages")]
  public class RemoveFieldRefactoryAction : ICodeActionProvider
  {
    public IEnumerable<CodeAction> GetActions(RefactoringContext context)
    {
      var fieldDeclaration = GetFieldDeclaration(context);
            if(fieldDeclaration==null)
          yield break;

      
      yield return new CodeAction(string.Format(context.TranslateString("Remove field '{0}'"), fieldDeclaration.Name)
                                  , script => GenerateNewScript(
                script, fieldDeclaration, context), fieldDeclaration);
    }
    
    
    void GenerateNewScript(Script script, FieldDeclaration fieldDeclaration, RefactoringContext context)
        {
            var firstOrNullObject = fieldDeclaration.Variables.FirstOrNullObject();
        if(firstOrNullObject==null)
                return;
      var matchedNodes = ComputeMatchNodes(context, firstOrNullObject);

        foreach (var matchNode in matchedNodes)
            {
                var parent = matchNode.Parent;
                if (matchNode is VariableInitializer)
                {
                    script.Remove(parent);
                }
                else
                if (matchNode is IdentifierExpression)
                {
                    if(parent is AssignmentExpression)
                    {
                        script.Remove(parent.Parent);
                    }
                    else
                    {
                        var clone = (IdentifierExpression)matchNode.Clone();
                        clone.Identifier = "TODO";
                        script.Replace(matchNode, clone);
                    }
                }
            }
        }

      private static List<AstNode> ComputeMatchNodes(RefactoringContext context, VariableInitializer firstOrNullObject)
      {
          var referenceFinder = new FindReferences();
          var matchedNodes = new List<AstNode>();

          var resolveResult = context.Resolver.Resolve(firstOrNullObject);
          var member = resolveResult as MemberResolveResult;
            if (member == null)//not a member is unexpected case, so is better to return no match than to break the code
                return matchedNodes;

          FoundReferenceCallback callback = (matchNode, result) => matchedNodes.Add(matchNode);

          var searchScopes = referenceFinder.GetSearchScopes(member.Member);
          referenceFinder.FindReferencesInFile(searchScopes,
                                               context.UnresolvedFile,
                                               context.RootNode as SyntaxTree,
                                               context.Compilation, callback,
                                               context.CancellationToken);
          return matchedNodes;
      }

      FieldDeclaration GetFieldDeclaration(RefactoringContext context)
    {
      var result = context.GetNode<FieldDeclaration>();

      return result;
    }
  }
}