platform/lang-impl/src/com/intellij/psi/codeStyle/arrangement/engine/RestoreFoldArrangementCallback.java

/*
 * Copyright 2000-2012 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.intellij.psi.codeStyle.arrangement.engine;

import com.intellij.codeInsight.folding.CodeFoldingManager;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.editor.FoldRegion;
import com.intellij.openapi.project.Project;
import org.jetbrains.annotations.NotNull;

import java.util.ArrayList;
import java.util.List;

/**
 * @author Denis Zhdanov
 * @since 11/21/12 12:57 PM
 */
public class RestoreFoldArrangementCallback implements ArrangementCallback {

  @NotNull private final  Editor           myEditor;

  public RestoreFoldArrangementCallback(@NotNull Editor editor) {
    myEditor = editor;
  }

  @Override
  public void afterArrangement(@NotNull final List<ArrangementMoveInfo> moveInfos) {
    // Restore state for the PSI elements not affected by arrangement.
    Project project = myEditor.getProject();
    if (project != null) {
      final FoldRegion[] regions = myEditor.getFoldingModel().getAllFoldRegions();
      final List<FoldRegionInfo> foldRegionsInfo = new ArrayList<FoldRegionInfo>();
      for (FoldRegion region : regions) {
        final FoldRegionInfo info = new FoldRegionInfo(region.getStartOffset(), region.getEndOffset(), region.isExpanded());
        foldRegionsInfo.add(info);
      }

      final CodeFoldingManager foldingManager = CodeFoldingManager.getInstance(project);
      foldingManager.updateFoldRegions(myEditor);
      myEditor.getFoldingModel().runBatchFoldingOperation(new Runnable() {
        @Override
        public void run() {
          for (FoldRegionInfo info : foldRegionsInfo) {
            final FoldRegion foldRegion = foldingManager.findFoldRegion(myEditor, info.myStart, info.myEnd);
            if (foldRegion != null) {
              foldRegion.setExpanded(info.myIsExpanded);
            }
          }
        }
      });
    }
  }

  private static class FoldRegionInfo {
    private int myStart;
    private int myEnd;
    private boolean myIsExpanded;

    private FoldRegionInfo(int start, int end, boolean expanded) {
      myStart = start;
      myEnd = end;
      myIsExpanded = expanded;
    }
  }
}