platform/lang-impl/src/com/intellij/codeInsight/editorActions/enter/EnterBetweenBracesHandler.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.codeInsight.editorActions.enter;

import com.intellij.codeInsight.CodeInsightSettings;
import com.intellij.codeInsight.editorActions.CodeDocumentationUtil;
import com.intellij.openapi.actionSystem.DataContext;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.editor.Document;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.editor.actionSystem.EditorActionHandler;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.Ref;
import com.intellij.psi.PsiDocumentManager;
import com.intellij.psi.PsiFile;
import com.intellij.psi.codeStyle.CodeStyleManager;
import com.intellij.psi.codeStyle.CodeStyleSettingsManager;
import com.intellij.util.IncorrectOperationException;
import org.jetbrains.annotations.NotNull;

public class EnterBetweenBracesHandler extends EnterHandlerDelegateAdapter {
  private static final Logger LOG = Logger.getInstance("#com.intellij.codeInsight.editorActions.enter.EnterBetweenBracesHandler");

  @Override
  public Result preprocessEnter(@NotNull final PsiFile file, @NotNull final Editor editor, @NotNull final Ref<Integer> caretOffsetRef, @NotNull final Ref<Integer> caretAdvance,
                                @NotNull final DataContext dataContext, final EditorActionHandler originalHandler) {
    Document document = editor.getDocument();
    CharSequence text = document.getCharsSequence();
    int caretOffset = caretOffsetRef.get().intValue();
    if (!CodeInsightSettings.getInstance().SMART_INDENT_ON_ENTER) {
      return Result.Continue;
    }
    
    if (caretOffset <= 0 || caretOffset >= text.length() || !isBracePair(text.charAt(caretOffset - 1), text.charAt(caretOffset)) ||
      file.findElementAt(caretOffset) == file.findElementAt(caretOffset-1)) {
      return Result.Continue;
    }

    final int line = document.getLineNumber(caretOffset);
    final int start = document.getLineStartOffset(line);
    final CodeDocumentationUtil.CommentContext commentContext =
      CodeDocumentationUtil.tryParseCommentContext(file, text, caretOffset, start);

    // special case: enter inside "()" or "{}"
    String indentInsideJavadoc = commentContext.docAsterisk
                                 ? CodeDocumentationUtil.getIndentInsideJavadoc(document, caretOffset)
                                 : null;

    originalHandler.execute(editor, dataContext);

    Project project = editor.getProject();
    if (indentInsideJavadoc != null && project != null && CodeStyleSettingsManager.getSettings(project).JD_LEADING_ASTERISKS_ARE_ENABLED) {
      document.insertString(editor.getCaretModel().getOffset(), "*" + indentInsideJavadoc);
    }

    PsiDocumentManager.getInstance(file.getProject()).commitDocument(document);
    try {
      CodeStyleManager.getInstance(file.getProject()).adjustLineIndent(file, editor.getCaretModel().getOffset());
    }
    catch (IncorrectOperationException e) {
      LOG.error(e);
    }
    return indentInsideJavadoc == null ? Result.Continue : Result.DefaultForceIndent;
  }

  protected boolean isBracePair(char c1, char c2) {
    return (c1 == '(' && c2 == ')') || (c1 == '{' && c2 == '}');
  }
}