/*
    * Created on 23.09.2004
    */
   package myx;
   
   import java.io.File;
   import java.io.StringReader;
   import java.util.Iterator;
   import java.util.List;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  
  import javax.xml.transform.TransformerException;
  import javax.xml.transform.sax.SAXSource;
  import javax.xml.transform.stream.StreamSource;
  
  import net.sf.saxon.Configuration;
  import net.sf.saxon.om.NodeInfo;
  import net.sf.saxon.om.SequenceIterator;
  import net.sf.saxon.query.DynamicQueryContext;
  //import net.sf.saxon.query.QueryProcessor;
  import net.sf.saxon.query.StaticQueryContext;
  import net.sf.saxon.query.XQueryExpression;
  import net.sf.saxon.xpath.XPathEvaluator;
  import net.sf.saxon.trans.XPathException;
  import net.sf.saxon.sxpath.XPathExpression;
  
  import org.xml.sax.InputSource;
  import org.xmldb.api.base.Collection;
  import org.xmldb.api.base.ErrorCodes;
  import org.xmldb.api.base.Resource;
  import org.xmldb.api.base.ResourceSet;
  import org.xmldb.api.base.XMLDBException;
  import org.xmldb.api.modules.XPathQueryService;
  import org.xmldb.api.reference.ResourceSetImpl;
  import org.xmldb.api.reference.modules.XMLResourceImpl;
  
  /***
   * @author Mladen Adamovic (adamm@blic.net)
   */
  public class myxXQuerySaxonService implements XPathQueryService {
      private static Logger logger = Logger.getLogger(myxXQuerySaxonService.class.getName());
  
      Collection col;
  
      /***
       *  
       */
      public myxXQuerySaxonService() {
          super();
      }
  
      /***
       * @param col
       */
      public myxXQuerySaxonService(Collection col) {
          super();
          this.col = col;
      }
  
      /***
       * @see org.xmldb.api.modules.XPathQueryService#setNamespace(java.lang.String,
       *      java.lang.String)
       */
      public void setNamespace(String prefix, String uri) throws XMLDBException {
          // TODO Auto-generated method stub
  
      }
  
      /***
       * @see org.xmldb.api.modules.XPathQueryService#getNamespace(java.lang.String)
       */
      public String getNamespace(String prefix) throws XMLDBException {
          // TODO Auto-generated method stub
          return null;
      }
  
      /***
       * @see org.xmldb.api.modules.XPathQueryService#removeNamespace(java.lang.String)
       */
      public void removeNamespace(String prefix) throws XMLDBException {
          // TODO Auto-generated method stub
  
      }
  
      /***
       * @see org.xmldb.api.modules.XPathQueryService#clearNamespaces()
       */
      public void clearNamespaces() throws XMLDBException {
          // TODO Auto-generated method stub
  
      }
  
      /***
       * @see org.xmldb.api.modules.XPathQueryService#query(java.lang.String)
       * 
       * Use iterator over Collections.listChildCollections() and call
       * queryResource
       */
     public ResourceSet query(String query) throws XMLDBException {
         logger.fine("col :" + col);
         String resNames[] = col.listResources();
         int i;
         long j;
         logger.fine("resNames :" + resNames);
         logger.fine("resNames.length :" + resNames.length);
 
         ResourceSet result = new ResourceSetImpl(col), qrs;
         for (i = 0; i < resNames.length; i++) {
             logger.fine("querying " + resNames[i] + "...");
             qrs = queryResource(resNames[i], query);
             //now we have to do result+=qrs
             for (j = 0; j < qrs.getSize(); j++) {
                 Resource res = qrs.getResource(j);
                 result.addResource(res);
             }
         }
         return result;
     }
 
     /***
      * @see org.xmldb.api.modules.XPathQueryService#queryResource(java.lang.String,
      *      java.lang.String)
      */
     public ResourceSet queryResource(String id, String query)
             throws XMLDBException {
         String content = (String) col.getResource(id).getContent();
 
         /*
          * InputSource is=new InputSource(new StringReader(content)); List
          * matched; SAXSource ss = new SAXSource(is); try { XPathEvaluator xpe =
          * new XPathEvaluator(ss);
          *  // Compile the XPath expressions used by the application
          * XPathExpression extract = xpe.createExpression(query); matched =
          * extract.evaluate(); } catch(XPathException e) { e.printStackTrace();
          * throw new XMLDBException(ErrorCodes.VENDOR_ERROR, "XPathException"); }
          * 
          * ResourceSetImpl rs=null;
          * 
          * //we have to convert this list of Nodes into ResourceSet rs = new
          * ResourceSetImpl(col);
          * 
          * for (Iterator iter = matched.iterator(); iter.hasNext();) { // Get
          * the next matching line NodeInfo ni = (NodeInfo) iter.next();
          * XMLResourceImpl xmlResource = new XMLResourceImpl(col, "QueryResult",
          * "QueryResult", ni.getStringValue()); rs.addResource(xmlResource);
          *  } return rs;
          */
         Configuration config = new Configuration();
         StaticQueryContext staticContext = new StaticQueryContext(config);
         //QueryProcessor xquery = new QueryProcessor(staticContext);
         StaticQueryContext xquery = new StaticQueryContext(config);
         XQueryExpression exp;
         ResourceSetImpl rs = null;
         SequenceIterator iter;
         try {
             exp = xquery.compileQuery(query);
 
             DynamicQueryContext dynamicContext = new DynamicQueryContext(config);
             try {
                 dynamicContext.setContextNode(xquery.buildDocument(new StreamSource(new StringReader(
                                 content))));
                 iter = exp.iterator(dynamicContext);
             } catch (TransformerException e) {
                 throw new XMLDBException(ErrorCodes.VENDOR_ERROR,
                         "TransformerException when tring to invoke query : "
                                 + query + "\n" + e.getMessage());
 
             }
 
             //we have to convert this list of Nodes into ResourceSet
             rs = new ResourceSetImpl(col);
 
             while (true) {
                 NodeInfo ni = (NodeInfo) iter.next();
                 if (ni == null)
                     break;
                 String data = ni.getStringValue();
                 XMLResourceImpl xmlResource = new XMLResourceImpl(col,
                         "QueryResult", "QueryResult", ni.getStringValue());
                 rs.addResource(xmlResource);
 
             }
         } catch (XPathException e) {
             throw new XMLDBException(ErrorCodes.VENDOR_ERROR,
                     "XpathException when tring to invoke query : " + query
                             + "\n" + e.getMessage());
         }
 
         return rs;
     }
 
     /***
      * @see org.xmldb.api.base.Service#getName()
      */
     public String getName() throws XMLDBException {
         // TODO Auto-generated method stub
         return null;
     }
 
     /***
      * @see org.xmldb.api.base.Service#getVersion()
      */
     public String getVersion() throws XMLDBException {
         // TODO Auto-generated method stub
         return null;
     }
 
     /***
      * @see org.xmldb.api.base.Service#setCollection(org.xmldb.api.base.Collection)
      */
     public void setCollection(Collection col) throws XMLDBException {
         this.col = col;
     }
 
     /***
      * @see org.xmldb.api.base.Configurable#getProperty(java.lang.String)
      */
     public String getProperty(String name) throws XMLDBException {
         // TODO Auto-generated method stub
         return null;
     }
 
     /***
      * @see org.xmldb.api.base.Configurable#setProperty(java.lang.String,
      *      java.lang.String)
      */
     public void setProperty(String name, String value) throws XMLDBException {
         // TODO Auto-generated method stub
 
     }
 
 }