platform/platform-impl/src/com/intellij/openapi/diff/impl/highlighting/SimpleDiffPanelState.java

/*
 * Copyright 2000-2009 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.openapi.diff.impl.highlighting;

import com.intellij.openapi.Disposable;
import com.intellij.openapi.application.ApplicationManager;
import com.intellij.openapi.diff.impl.ComparisonPolicy;
import com.intellij.openapi.diff.impl.ContentChangeListener;
import com.intellij.openapi.diff.impl.fragments.*;
import com.intellij.openapi.diff.impl.processing.DiffPolicy;
import com.intellij.openapi.diff.impl.processing.HighlightMode;
import com.intellij.openapi.diff.impl.processing.TextCompareProcessor;
import com.intellij.openapi.diff.impl.splitter.LineBlocks;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.Disposer;
import com.intellij.util.diff.FilesTooBigForDiffException;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

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

public abstract class SimpleDiffPanelState implements Disposable  {
  protected ComparisonPolicy myComparisonPolicy = ComparisonPolicy.DEFAULT;
  protected DiffPolicy myDiffPolicy;
  protected HighlightMode myHighlightMode;
  protected final EditorPlaceHolder myAppender1;
  protected final EditorPlaceHolder myAppender2;
  protected FragmentList myFragmentList = FragmentList.EMPTY;
  protected final Project myProject;

  public SimpleDiffPanelState(Project project, ContentChangeListener changeListener, @NotNull Disposable parentDisposable) {
    myAppender1 = createEditorWrapper(project, changeListener, FragmentSide.SIDE1);
    myAppender2 = createEditorWrapper(project, changeListener, FragmentSide.SIDE2);
    myProject = project;
    myDiffPolicy = DiffPolicy.LINES_WO_FORMATTING;
    myHighlightMode = HighlightMode.BY_WORD;
    Disposer.register(parentDisposable, this);
  }

  private EditorPlaceHolder createEditorWrapper(Project project, ContentChangeListener changeListener, FragmentSide side) {
    EditorPlaceHolder editorWrapper = new EditorPlaceHolder(side, project, this);
    editorWrapper.addListener(changeListener);
    return editorWrapper;
  }
  
  public void setComparisonPolicy(ComparisonPolicy comparisonPolicy) {
    myComparisonPolicy = comparisonPolicy;
  }

  public void setDiffPolicy(DiffPolicy diffPolicy) {
    myDiffPolicy = diffPolicy;
  }

  public DiffPolicy getDiffPolicy() {
    return myDiffPolicy;
  }

  public ComparisonPolicy getComparisonPolicy() {
    return myComparisonPolicy;
  }

  public HighlightMode getHighlightMode() {
    return myHighlightMode;
  }

  public void setHighlightMode(HighlightMode highlightMode) {
    myHighlightMode = highlightMode;
  }

  public void dispose() {
  }

  private LineBlocks addMarkup(final List<LineFragment> lines) {
    ApplicationManager.getApplication().runWriteAction(new Runnable() {
      public void run() {
        final FragmentHighlighterImpl fragmentHighlighter = new FragmentHighlighterImpl(myAppender1, myAppender2);
        for (Iterator<LineFragment> iterator = lines.iterator(); iterator.hasNext();) {
          LineFragment line = iterator.next();
          fragmentHighlighter.setIsLast(!iterator.hasNext());
          line.highlight(fragmentHighlighter);
        }
      }
    });
    ArrayList<LineFragment> allLineFragments = new ArrayList<LineFragment>();
    for (LineFragment lineFragment : lines) {
      allLineFragments.add(lineFragment);
      lineFragment.addAllDescendantsTo(allLineFragments);
    }
    myFragmentList = FragmentListImpl.fromList(allLineFragments);
    return LineBlocks.fromLineFragments(allLineFragments);
  }

  private void resetMarkup() {
    ApplicationManager.getApplication().runWriteAction(new ResetMarkupRunnable(this));
  }

  @Nullable
  public LineBlocks updateEditors() throws FilesTooBigForDiffException {
    resetMarkup();
    if (myAppender1.getEditor() == null || myAppender2.getEditor() == null) {
      return null;
    }

    return addMarkup(
      new TextCompareProcessor(myComparisonPolicy, myDiffPolicy, myHighlightMode).process(myAppender1.getText(), myAppender2.getText()));
  }

  public Project getProject() { return myProject; }

  public FragmentList getFragmentList() { return myFragmentList; }

  private static class ResetMarkupRunnable implements Runnable {
    private final SimpleDiffPanelState myState;

    public ResetMarkupRunnable(SimpleDiffPanelState state) {
      myState = state;
    }

    public void run() {
      myState.myAppender1.resetHighlighters();
      myState.myAppender2.resetHighlighters();
    }
  }
}