// ***********************************************************************************
// $Source: /home/cvsroot/nodus/src/com/bbn/openmap/plugin/wms/WmsXmlParser.java,v $
// $RCSfile: WmsXmlParser.java,v $
// $Revision: 1.11 $
// $Date: 2004/10/25 15:47:30 $
// $Author: jourquin $
// ***********************************************************************************


package com.bbn.openmap.plugin.wms;

import org.xml.sax.*;
import org.xml.sax.helpers.*;
import java.util.Properties;
import org.fucam.gtm.nodus.*;

/**
 *
 * <p>Title: Nodus 5.0</p>
 * <p>Description: Simple XML parser that tries to get a list of unique layer names
    It could be extended to get more capabilities...</p>
 * <p>Copyright : Copyright (c) 2004</p>
 * <p>Société : FUCaM-GTM</p>
 * @author Bart Jourquin
 * @version 1.0
 */
public class WmsXmlParser extends DefaultHandler implements INodusConstants {

private String xmlKey;
private Properties capabilities;
private String pathPrefix;

  /**
   * The parsed data will be stored in the properties, with a given prefix
   * @param prefix String
   * @param prop Properties
   */
  public WmsXmlParser(String prefix, Properties prop) {
    pathPrefix = prefix;
    capabilities = prop;
  }

  /**
   * Stores a new unique layer name in the properties. See Xerces's documentation for more details on how the
   * parsing of an XML formatted stream works.
   * @param ch char[]
   * @param start int
   * @param length int
   * @throws SAXException
   */
  public void characters(char[] ch, int start, int length) throws SAXException {
    String s = new String(ch, start, length);
    if (ch[0] == '\n') {
      return;
    }
   //System.out.println(XMLKey + " " +s);
    if (xmlKey.indexOf("WMT_MS_Capabilities.Capability.Layer.") != -1 && xmlKey.endsWith(".Name") && xmlKey.indexOf("Style") == -1) {
      String availableLayer = capabilities.getProperty(pathPrefix + PROP_AVAILABLE_LAYERS, "");
      if (availableLayer.lastIndexOf(s) == -1) { // Keep unique value
         StringBuffer sb1 = new StringBuffer(availableLayer);
         if (sb1.length() > 0) {
          sb1.append(',');
          }
         sb1.append(s);
         capabilities.put(pathPrefix + PROP_AVAILABLE_LAYERS, sb1.toString());
         }
      }
  }

  /**
   * Tells to the XML parser that the keys are separated with a dot. See Xerce's documentation
   * for more details on how the parsing of an XML stream works
   * @param uri String
   * @param localName String
   * @param qName String
   * @throws SAXException
   */
  public void endElement(String uri, String localName, String qName) throws SAXException {
    int i = xmlKey.lastIndexOf('.');
    if (i != -1) {
      xmlKey = xmlKey.substring(0, i);
    }
  }

  /**
   * See Xerce's documentation
   * for more details on how the parsing of an XML stream works
   * @throws SAXException
   */
  public void startDocument() throws SAXException {
    xmlKey = new String("");
  }

  /**
   * Tells to the XML parser that the keys are separated with a dot. See Xerce's documentation
   * for more details on how the parsing of an XML stream works
   * @param uri String
   * @param localName String
   * @param qName String
   * @param attributes Attributes
   * @throws SAXException
   */
  public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
    if (xmlKey.length() > 0) {
      xmlKey += ".";
    }
    xmlKey += localName;
  }
}