plugins/groovy/src/org/jetbrains/plugins/groovy/lang/groovydoc/psi/impl/GrDocCommentUtil.java

/*
 * Copyright 2000-2013 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 org.jetbrains.plugins.groovy.lang.groovydoc.psi.impl;

import com.intellij.lang.ASTNode;
import com.intellij.psi.PsiElement;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.jetbrains.plugins.groovy.lang.groovydoc.psi.api.GrDocComment;
import org.jetbrains.plugins.groovy.lang.groovydoc.psi.api.GrDocCommentOwner;
import org.jetbrains.plugins.groovy.lang.groovydoc.psi.api.GroovyDocPsiElement;
import org.jetbrains.plugins.groovy.lang.lexer.GroovyTokenTypes;
import org.jetbrains.plugins.groovy.lang.psi.api.statements.GrVariable;
import org.jetbrains.plugins.groovy.lang.psi.api.statements.GrVariableDeclaration;

import static org.jetbrains.plugins.groovy.lang.groovydoc.parser.GroovyDocElementTypes.GROOVY_DOC_COMMENT;
import static org.jetbrains.plugins.groovy.lang.lexer.TokenSets.WHITE_SPACES_OR_COMMENTS;

/**
 * @author Maxim.Medvedev
 */
public abstract class GrDocCommentUtil {
  @Nullable
  public static GrDocCommentOwner findDocOwner(GroovyDocPsiElement docElement) {
    PsiElement element = docElement;
    while (element != null && element.getParent() instanceof GroovyDocPsiElement) element = element.getParent();
    if (element == null) return null;

    element = skipWhiteSpacesAndStopOnDoc(element, true);

    if (element instanceof GrDocCommentOwner) return (GrDocCommentOwner)element;
    return null;
  }

  @Nullable
  public static GrDocComment findDocComment(GrDocCommentOwner owner) {
    if (owner.getFirstChild() instanceof GrDocComment) {
      return ((GrDocComment)owner.getFirstChild());
    }

    PsiElement element = owner instanceof GrVariable && owner.getParent() instanceof GrVariableDeclaration ? owner.getParent() : owner;

    element = skipWhiteSpacesAndStopOnDoc(element, false);
    if (element instanceof GrDocComment) return (GrDocComment)element;
    return null;
  }

  private static PsiElement skipWhiteSpacesAndStopOnDoc(PsiElement element, boolean forward) {
    while (true) {
      element = forward ? element.getNextSibling() : element.getPrevSibling();
      if (element == null) break;
      final ASTNode node = element.getNode();
      if (node == null) break;
      if (GROOVY_DOC_COMMENT.equals(node.getElementType()) ||
          !WHITE_SPACES_OR_COMMENTS.contains(node.getElementType())) {
        break;
      }
    }
    return element;
  }

  public static GrDocComment setDocComment(@NotNull GrDocCommentOwner owner, @Nullable GrDocComment comment) {
    GrDocComment docComment = owner.getDocComment();

    if (docComment != null) {
      if (comment == null) {
        docComment.delete();
        return null;
      }
      else {
        PsiElement added = docComment.replace(comment);
        assert added instanceof GrDocComment;
        return (GrDocComment)added;
      }
    }
    else {
      if (comment == null) return null;

      PsiElement parent = owner.getParent();

      ASTNode node = owner.getNode();
      parent.getNode().addLeaf(GroovyTokenTypes.mNLS, "\n ", node);

      PsiElement added = parent.addBefore(comment, owner);
      assert added instanceof GrDocComment;

      return (GrDocComment)added;
    }
  }
}