/*
    * 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 org.apache.felix.bundleplugin;
  
  
  import java.io.BufferedReader;
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.net.URL;
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Set;
  
  import javax.xml.transform.Transformer;
  import javax.xml.transform.TransformerFactory;
  import javax.xml.transform.stream.StreamResult;
  import javax.xml.transform.stream.StreamSource;
  
  import aQute.bnd.osgi.Analyzer;
  import aQute.bnd.osgi.Processor;
  import aQute.bnd.osgi.Resource;
  import aQute.bnd.service.AnalyzerPlugin;
  import aQute.libg.generics.Create;
  
  
  public class JpaPlugin implements AnalyzerPlugin
  {
  
      Transformer transformer;
  
  
      public JpaPlugin() throws Exception
      {
          transformer = getTransformer( getClass().getResource( "jpa.xsl" ) );
      }
  
  
      public boolean analyzeJar( Analyzer analyzer ) throws Exception
      {
          Set<String> headers = Create.set();
  
          String mpHeader = analyzer.getProperty( "Meta-Persistence" );
  
          transformer.setParameter( "jpa-enable", analyzer.getProperty( "jpa-enable", "true" ) );
          transformer.setParameter( "jpa-implementation", analyzer.getProperty( "jpa-implementation", "aries" ) );
          transformer.setParameter( "jpa-datasource-req", analyzer.getProperty( "jpa-datasource-req", "true" ) );
  
          Map<String, ? extends Map<String, String>> map = Processor.parseHeader( mpHeader, null );
          for ( String root : map.keySet() )
          {
              Resource resource = analyzer.getJar().getResource(root);
              if ( resource != null ) {
                  process(analyzer, root, resource, headers);
              }
          }
  
          // Group and analyze
          for ( String str : headers )
          {
              int idx = str.indexOf( ':' );
              if ( idx < 0 )
              {
                  analyzer.warning( ( new StringBuilder( "Error analyzing services in scr resource: " ) ).append( str ).toString() );
                  continue;
              }
              String h = str.substring( 0, idx ).trim();
              String v = str.substring( idx + 1 ).trim();
  
              StringBuilder sb = new StringBuilder();
              String header = analyzer.getProperty( h );
              if (header != null && !header.isEmpty())
              {
                  sb.append(header);
                  sb.append(",");
              }
              sb.append( v );
              analyzer.setProperty(h, sb.toString());
          }
          return false;
      }
 
 
     private void process( Analyzer analyzer, String path, Resource resource, Set<String> headers )
     {
         InputStream in = null;
         try
         {
             in = resource.openInputStream();
 
             // Retrieve headers
             Set<String> set = analyze( in );
 System.err.println("Output: " + set.toString());
             headers.addAll( set );
         }
         catch ( Exception e )
         {
             analyzer.error( ( new StringBuilder( "Unexpected exception in processing spring resources(" ) )
                 .append( path ).append( "): " ).append( e ).toString() );
         }
         finally
         {
             try
             {
                 if ( in != null )
                 {
                     in.close();
                 }
             }
             catch ( IOException e )
             {
             }
         }
     }
 
 
     public Set<String> analyze( InputStream in ) throws Exception
     {
         Set<String> refers = new HashSet<String>();
         ByteArrayOutputStream bout = new ByteArrayOutputStream();
         javax.xml.transform.Result r = new StreamResult( bout );
         javax.xml.transform.Source s = new StreamSource( in );
         transformer.transform( s, r );
         ByteArrayInputStream bin = new ByteArrayInputStream( bout.toByteArray() );
         bout.close();
         BufferedReader br = new BufferedReader( new InputStreamReader( bin ) );
         for ( String line = br.readLine(); line != null; line = br.readLine() )
         {
             line = line.trim();
             if ( line.length() > 0 )
             {
                 refers.add( line );
             }
         }
 
         br.close();
         return refers;
     }
 
 
     protected Transformer getTransformer( URL url ) throws Exception
     {
         TransformerFactory tf = TransformerFactory.newInstance();
         javax.xml.transform.Source source = new StreamSource( url.openStream() );
         return tf.newTransformer( source );
     }
 
 }