/*
    * Copyright 2003 - 2013 The eFaps Team
    *
    * 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.
   *
   * Revision:        $Rev$
   * Last Changed:    $Date$
   * Last Changed By: $Author$
   */
  
  
  package org.efaps.update.schema.program.staticsource;
  
  import java.io.IOException;
  import java.net.URL;
  import java.util.UUID;
  
  import javax.xml.parsers.DocumentBuilder;
  import javax.xml.parsers.DocumentBuilderFactory;
  import javax.xml.parsers.ParserConfigurationException;
  
  import org.efaps.ci.CIAdminProgram;
  import org.efaps.update.schema.program.AbstractSourceImporter;
  import org.efaps.update.util.InstallationException;
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  import org.w3c.dom.Node;
  import org.w3c.dom.NodeList;
  import org.xml.sax.SAXException;
  
  /**
   * TODO comment!
   *
   * @author The eFaps Team
   * @version $Id$
   */
  public class BPMImporter
      extends AbstractSourceImporter
  {
      /**
       * Possible tagnames for the process tag.
       */
      private static String[] PROCESSTAGNAMES = new String[] {"process", "bpmn2:process"};
  
      /**
       * Default constructor.
       *
       * @param _url      URL to the XSLT file
       * @throws InstallationException if BPM importer could not be initialized
       *                               because file from <code>_url</code> could
       *                               not be read
       */
      public BPMImporter(final URL _url)
          throws InstallationException
      {
          super(CIAdminProgram.BPM, _url);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      protected String evalProgramName()
          throws InstallationException
      {
          String ret = "";
          try {
              final DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
              final DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
              final Document doc = dBuilder.parse(getUrl().openStream(), AbstractSourceImporter.ENCODING);
              doc.getDocumentElement().normalize();
  
              for (final String tagName  : BPMImporter.PROCESSTAGNAMES) {
                  final NodeList processNodeList = doc.getElementsByTagName(tagName);
                  if (processNodeList != null && processNodeList.getLength() > 0) {
                      final Node processNode = processNodeList.item(0);
                      if (processNode.getNodeType() == Node.ELEMENT_NODE) {
                          final Element eElement = (Element) processNode;
                          ret = eElement.getAttribute("id");
                      }
                      break;
                  }
              }
          } catch (final ParserConfigurationException e) {
              throw new InstallationException("could not Parse the given URL", e);
          } catch (final SAXException e) {
              throw new InstallationException("could not Parse the given URL", e);
          } catch (final IOException e) {
              throw new InstallationException("could not Read the given URL", e);
         }
         return ret;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     protected UUID evalUUID()
     {
         return null;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     protected String evalRevision()
         throws InstallationException
     {
         String ret = "";
         try {
             final DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
             final DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
             final Document doc = dBuilder.parse(getUrl().openStream(), AbstractSourceImporter.ENCODING);
             doc.getDocumentElement().normalize();
 
             for (final String tagName  : BPMImporter.PROCESSTAGNAMES) {
                 final NodeList processNodeList = doc.getElementsByTagName(tagName);
                 if (processNodeList != null && processNodeList.getLength() > 0) {
                     final Node processNode = processNodeList.item(0);
                     if (processNode.getNodeType() == Node.ELEMENT_NODE) {
                         final Element eElement = (Element) processNode;
                         ret = eElement.getAttribute("tns:version");
                     }
                     break;
                 }
             }
         } catch (final ParserConfigurationException e) {
             throw new InstallationException("could not Parse the given URL", e);
         } catch (final SAXException e) {
             throw new InstallationException("could not Parse the given URL", e);
         } catch (final IOException e) {
             throw new InstallationException("could not Read the given URL", e);
         }
         return ret;
     }
 }