/*
 * 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 parser.extension;

import java.util.Map;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;

import org.xml.sax.Attributes;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;

import groovy.util.Node;
import groovy.util.XmlParser;
import groovy.xml.QName;

/**
 * Extend XmlParser class to support recording the location 
 *    (file name, line number, column number)
 * of every element created, so that later processing can issue
 * error messages about the XML and refer to the file, line, col 
 * where the user should look.
 * 
 * Also - convert the element names (which are in this application QNames
 * because namespaces are used) and convert them to plain strings without
 * the namesapces.
 *
 */
public class XmlParserExt extends XmlParser {

  // Delegate the constructors (only some of them which were used in this app are here)
  public XmlParserExt() throws ParserConfigurationException, SAXException {
    this(false, true);
  }

  public XmlParserExt(boolean validating, boolean namespaceAware)
      throws ParserConfigurationException, SAXException {
    super(validating, namespaceAware);
  }
  
  public XmlParserExt(SAXParser parser) throws SAXException {
    super(parser);
  }

  public XmlParserExt(XMLReader reader) {
    super(reader);
  }

  // Override the newNodeInstance to create the subtype of Node having location info
  protected Node newNodeInstance(Node parent, Object name, Map attributes, Object value) {
    return new NodeWithLoc(parent, name, attributes, value);
  }

  // Override the startElement to capture the location information from the parser and
  // add it to the created node
  
  // Also, modify the name to be a plain string, the local part of the qname
  
  public void startElement(String namespaceURI, String localName, String qName, Attributes list)
  throws SAXException {
  super.startElement(namespaceURI, localName, qName, list);
  Locator el = getDocumentLocator();
  
  NodeWithLoc node = ((NodeWithLoc)getParent());
  node.setPublicId(el.getPublicId());
  node.setSystemId(el.getSystemId());
  node.setLineNbr(el.getLineNumber());
  node.setColNbr(el.getColumnNumber());
  
   // strip namespace stuff, too
  getParent().setName(((QName)getParent().name()).getLocalPart());
  }
}