package org.apache.maven.model.transform;
   
   /*
    * 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.util.List;
  import java.util.function.BiFunction;
  
  import org.apache.maven.model.transform.pull.NodeBufferingParser;
  import org.codehaus.plexus.util.xml.pull.XmlPullParser;
  
  /**
   * Will apply the version if the dependency is part of the reactor
   *
   * @author Robert Scholte
   * @author Guillaume Nodet
   * @since 4.0.0
   */
  public class ReactorDependencyXMLFilter extends NodeBufferingParser
  {
      private final BiFunction<String, String, String> reactorVersionMapper;
  
      public ReactorDependencyXMLFilter( XmlPullParser xmlPullParser,
                                         BiFunction<String, String, String> reactorVersionMapper )
      {
          super( xmlPullParser, "dependency" );
          this.reactorVersionMapper = reactorVersionMapper;
      }
  
      protected void process( List<Event> buffer )
      {
          // whiteSpace after <dependency>, to be used to position <version>
          String dependencyWhitespace = "";
          boolean hasVersion = false;
          String groupId = null;
          String artifactId = null;
          String tagName = null;
          for ( int i = 0; i < buffer.size(); i++ )
          {
              Event event = buffer.get( i );
              if ( event.event == START_TAG )
              {
                  tagName = event.name;
                  hasVersion |= "version".equals( tagName );
              }
              else if ( event.event == TEXT )
              {
                  if ( event.text.matches( "\\s+" ) )
                  {
                      if ( dependencyWhitespace.isEmpty() )
                      {
                          dependencyWhitespace = event.text;
                      }
                  }
                  else if ( "groupId".equals( tagName ) )
                  {
                      groupId = nullSafeAppend( groupId, event.text );
                  }
                  else if ( "artifactId".equals( tagName ) )
                  {
                      artifactId = nullSafeAppend( artifactId, event.text );
                  }
              }
              else if ( event.event == END_TAG && "dependency".equals( event.name ) )
              {
                  String version = reactorVersionMapper.apply( groupId, artifactId  );
                  if ( !hasVersion && version != null )
                  {
                      int pos = buffer.get( i - 1 ).event == TEXT ? i - 1  : i;
                      Event e = new Event();
                      e.event = TEXT;
                      e.text = dependencyWhitespace;
                      buffer.add( pos++, e );
                      e = new Event();
                      e.event = START_TAG;
                      e.namespace = buffer.get( 0 ).namespace;
                      e.prefix = buffer.get( 0 ).prefix;
                      e.name = "version";
                      buffer.add( pos++, e );
                      e = new Event();
                      e.event = TEXT;
                      e.text = version;
                      buffer.add( pos++, e );
                     e = new Event();
                     e.event = END_TAG;
                     e.name = "version";
                     e.namespace = buffer.get( 0 ).namespace;
                     e.prefix = buffer.get( 0 ).prefix;
                     buffer.add( pos++, e );
                 }
                 break;
             }
         }
         buffer.forEach( this::pushEvent );
     }
 
 }