/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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 nokogiri.internals.c14n;

import java.util.ArrayList;
import java.util.List;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

/**
 * @author Christian Geuer-Pollmann
 */
public class HelperNodeList implements NodeList
{

  /** Field nodes */
  List<Node> nodes = new ArrayList<Node>();
  boolean allNodesMustHaveSameParent = false;

  /**
   *
   */
  public
  HelperNodeList()
  {
    this(false);
  }


  /**
   * @param allNodesMustHaveSameParent
   */
  public
  HelperNodeList(boolean allNodesMustHaveSameParent)
  {
    this.allNodesMustHaveSameParent = allNodesMustHaveSameParent;
  }

  /**
   * Method item
   *
   * @param index
   * @return node with index i
   */
  public Node
  item(int index)
  {
    return nodes.get(index);
  }

  /**
   * Method getLength
   *
   *  @return length of the list
   */
  public int
  getLength()
  {
    return nodes.size();
  }

  /**
   * Method appendChild
   *
   * @param node
   * @throws IllegalArgumentException
   */
  public void
  appendChild(Node node) throws IllegalArgumentException
  {
    if (this.allNodesMustHaveSameParent && this.getLength() > 0
        && this.item(0).getParentNode() != node.getParentNode()) {
      throw new IllegalArgumentException("Nodes have not the same Parent");
    }
    nodes.add(node);
  }

  /**
   * @return the document that contains this nodelist
   */
  public Document
  getOwnerDocument()
  {
    if (this.getLength() == 0) {
      return null;
    }
    return XMLUtils.getOwnerDocument(this.item(0));
  }
}
