package org.apache.maven.plugin.invoker;
   
   /*
    * 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.IOException;
  import java.io.Reader;
  import java.io.Writer;
  import java.text.SimpleDateFormat;
  import java.util.Collection;
  import java.util.Date;
  import java.util.LinkedHashSet;
  import java.util.Set;
  import java.util.TimeZone;
  
  import org.apache.maven.artifact.Artifact;
  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.Xpp3DomUtils;
  import org.codehaus.plexus.util.xml.Xpp3DomWriter;
  import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
  
  /**
   * Provides utility methods for artifact metadata processing.
   * 
   * @author Benjamin Bentmann
   */
  class MetadataUtils
  {
  
      /**
       * Creates local metadata files for the specified artifact. The goal is to simulate the installation of the artifact
       * by a local build, thereby decoupling the forked builds from the inderministic collection of remote repositories
       * that are available to the main build and from which the artifact was originally resolved.
       * 
       * @param file The artifact's file in the local test repository, must not be <code>null</code>.
       * @param artifact The artifact to create metadata for, must not be <code>null</code>.
       * @throws IOException If the metadata could not be created.
       */
      public static void createMetadata( File file, Artifact artifact )
          throws IOException
      {
          TimeZone tz = java.util.TimeZone.getTimeZone( "UTC" );
          SimpleDateFormat fmt = new SimpleDateFormat( "yyyyMMddHHmmss" );
          fmt.setTimeZone( tz );
          String timestamp = fmt.format( new Date() );
  
          if ( artifact.isSnapshot() )
          {
              File metadataFile = new File( file.getParentFile(), "maven-metadata-local.xml" );
  
              Xpp3Dom metadata = new Xpp3Dom( "metadata" );
              addChild( metadata, "groupId", artifact.getGroupId() );
              addChild( metadata, "artifactId", artifact.getArtifactId() );
              addChild( metadata, "version", artifact.getBaseVersion() );
              Xpp3Dom versioning = new Xpp3Dom( "versioning" );
              versioning.addChild( addChild( new Xpp3Dom( "snapshot" ), "localCopy", "true" ) );
              addChild( versioning, "lastUpdated", timestamp );
              metadata.addChild( versioning );
  
              writeMetadata( metadataFile, metadata );
          }
  
          File metadataFile = new File( file.getParentFile().getParentFile(), "maven-metadata-local.xml" );
  
          Set<String> allVersions = new LinkedHashSet<String>();
  
          Xpp3Dom metadata = readMetadata( metadataFile );
  
          if ( metadata != null )
          {
              Xpp3Dom versioning = metadata.getChild( "versioning" );
              if ( versioning != null )
              {
                  Xpp3Dom versions = versioning.getChild( "versions" );
                  if ( versions != null )
                  {
  
                      Xpp3Dom[] children = versions.getChildren( "version" );
                     for ( Xpp3Dom aChildren : children )
                     {
                         allVersions.add( aChildren.getValue() );
                     }
                 }
             }
         }
 
         allVersions.add( artifact.getBaseVersion() );
 
         metadata = new Xpp3Dom( "metadata" );
         addChild( metadata, "groupId", artifact.getGroupId() );
         addChild( metadata, "artifactId", artifact.getArtifactId() );
         Xpp3Dom versioning = new Xpp3Dom( "versioning" );
         versioning.addChild( addChildren( new Xpp3Dom( "versions" ), "version", allVersions ) );
         addChild( versioning, "lastUpdated", timestamp );
         metadata.addChild( versioning );
 
         metadata = Xpp3DomUtils.mergeXpp3Dom( metadata, readMetadata( metadataFile ) );
 
         writeMetadata( metadataFile, metadata );
     }
 
     private static Xpp3Dom addChild( Xpp3Dom parent, String childName, String childValue )
     {
         Xpp3Dom child = new Xpp3Dom( childName );
         child.setValue( childValue );
         parent.addChild( child );
         return parent;
     }
 
     private static Xpp3Dom addChildren( Xpp3Dom parent, String childName, Collection<String> childValues )
     {
         for ( String childValue : childValues )
         {
             addChild( parent, childName, childValue );
         }
         return parent;
     }
 
     private static Xpp3Dom readMetadata( File metadataFile )
         throws IOException
     {
         if ( !metadataFile.isFile() )
         {
             return null;
         }
 
         Reader reader = ReaderFactory.newXmlReader( metadataFile );
         try
         {
             try
             {
                 return Xpp3DomBuilder.build( reader );
             }
             catch ( XmlPullParserException e )
             {
                 throw (IOException) new IOException( e.getMessage() ).initCause( e );
             }
         }
         finally
         {
             IOUtil.close( reader );
         }
     }
 
     private static void writeMetadata( File metadataFile, Xpp3Dom metadata )
         throws IOException
     {
         metadataFile.getParentFile().mkdirs();
 
         Writer writer = WriterFactory.newXmlWriter( metadataFile );
         try
         {
             Xpp3DomWriter.write( writer, metadata );
         }
         finally
         {
             IOUtil.close( writer );
         }
     }
 
 }