package org.apache.maven.plugins.shade.resource;
   
   /*
    * 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.
   */
  
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.io.Reader;
  import java.io.Writer;
  import java.util.Iterator;
  import java.util.LinkedHashMap;
  import java.util.Map;
  import java.util.jar.JarEntry;
  import java.util.jar.JarOutputStream;
  
  import org.codehaus.plexus.util.IOUtil;
  import org.codehaus.plexus.util.ReaderFactory;
  import org.codehaus.plexus.util.WriterFactory;
  import org.codehaus.plexus.util.xml.Xpp3Dom;
  import org.codehaus.plexus.util.xml.Xpp3DomBuilder;
  import org.codehaus.plexus.util.xml.Xpp3DomWriter;
  
  /**
   * A resource processor that aggregates plexus <code>components.xml</code> files.
   * 
   */
  public class ComponentsXmlResourceTransformer
      implements ResourceTransformer
  {
      private Map components = new LinkedHashMap();
  
      public static final String COMPONENTS_XML_PATH = "META-INF/plexus/components.xml";
  
      public boolean canTransformResource( String resource )
      {
          return COMPONENTS_XML_PATH.equals( resource );
      }
  
      public void processResource( InputStream is )
          throws IOException
      {
          // We can't just read the stream because the plexus dom builder closes the stream
  
          File f = File.createTempFile( "maven-shade-plugin", "tmp" );
  
          f.deleteOnExit();
  
          OutputStream os = new FileOutputStream( f );
  
          IOUtil.copy( is, os );
  
          os.close();
  
          //
  
          Reader reader;
  
          Xpp3Dom newDom;
  
          try
          {
              reader = ReaderFactory.newXmlReader( f );
  
              newDom = Xpp3DomBuilder.build( reader );
          }
          catch ( Exception e )
          {
              throw new IOException( "Error parsing components.xml in " + is );
          }
  
          // Only try to merge in components if there are some elements in the component-set
          if ( newDom.getChild( "components" ) == null )
          {
              return;
          }
  
          Xpp3Dom[] children = newDom.getChild( "components" ).getChildren( "component" );
  
          for ( int i = 0; i < children.length; i++ )
          {
             Xpp3Dom component = children[i];
 
             String role = component.getChild( "role" ).getValue();
 
             Xpp3Dom child = component.getChild( "role-hint" );
 
             String roleHint = child != null ? child.getValue() : "";
 
             String key = role + roleHint;
             if ( components.containsKey( key ) )
             {
                 // TODO: use the tools in Plexus to merge these properly. For now, I just need an all-or-nothing
                 // configuration carry over
 
                 Xpp3Dom dom = (Xpp3Dom) components.get( key );
                 if ( dom.getChild( "configuration" ) != null )
                 {
                     component.addChild( dom.getChild( "configuration" ) );
                 }
             }
 
             components.put( key, component );
         }
     }
 
     public void modifyOutputStream( JarOutputStream jos )
         throws IOException
     {
         Reader reader = ReaderFactory.newXmlReader( getTransformedResource() );
 
         jos.putNextEntry( new JarEntry( COMPONENTS_XML_PATH ) );
 
         IOUtil.copy( reader, jos );
 
         reader.close();
 
         components.clear();
     }
 
     public boolean hasTransformedResource()
     {
         return components.size() > 0;
     }
 
     public File getTransformedResource()
         throws IOException
     {
         File f = File.createTempFile( "shade-maven-plugin-plx", "tmp" );
 
         f.deleteOnExit();
 
         Writer writer = WriterFactory.newXmlWriter( f );
         try
         {
             Xpp3Dom dom = new Xpp3Dom( "component-set" );
 
             Xpp3Dom componentDom = new Xpp3Dom( "components" );
 
             dom.addChild( componentDom );
 
             for ( Iterator i = components.values().iterator(); i.hasNext(); )
             {
                 Xpp3Dom component = (Xpp3Dom) i.next();
                 componentDom.addChild( component );
             }
 
             Xpp3DomWriter.write( writer, dom );
         }
         finally
         {
             IOUtil.close( writer );
         }
 
         return f;
     }
 
 
 }