package org.apache.maven.tools.plugin.extractor;
   
   /*
    * 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.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import java.util.TreeMap;
  
  import org.apache.maven.plugin.descriptor.InvalidPluginDescriptorException;
  import org.apache.maven.plugin.descriptor.MojoDescriptor;
  import org.apache.maven.project.MavenProject;
  import org.apache.maven.tools.plugin.PluginToolsRequest;
  import org.codehaus.plexus.logging.AbstractLogEnabled;
  import org.codehaus.plexus.util.DirectoryScanner;
  import org.codehaus.plexus.util.FileUtils;
  import org.codehaus.plexus.util.StringUtils;
  
  /**
   * @author jdcasey
   */
  public abstract class AbstractScriptedMojoDescriptorExtractor
      extends AbstractLogEnabled
      implements MojoDescriptorExtractor
  {
      /** {@inheritDoc} */
      public List<MojoDescriptor> execute( PluginToolsRequest request )
          throws ExtractionException, InvalidPluginDescriptorException
      {
          getLogger().debug( "Running: " + getClass().getName() );
          String metadataExtension = getMetadataFileExtension( request );
          String scriptExtension = getScriptFileExtension( request );
          
          MavenProject project = request.getProject();
  
          @SuppressWarnings( "unchecked" )
          Map<String, Set<File>> scriptFilesKeyedByBasedir =
              gatherFilesByBasedir( project.getBasedir(), project.getScriptSourceRoots(), scriptExtension, request );
  
          List<MojoDescriptor> mojoDescriptors;
          if ( !StringUtils.isEmpty( metadataExtension ) )
          {
              @SuppressWarnings( "unchecked" )
              Map<String, Set<File>> metadataFilesKeyedByBasedir =
                  gatherFilesByBasedir( project.getBasedir(), project.getScriptSourceRoots(), metadataExtension,
                                        request );
  
              mojoDescriptors = extractMojoDescriptorsFromMetadata( metadataFilesKeyedByBasedir, request );
          }
          else
          {
              mojoDescriptors = extractMojoDescriptors( scriptFilesKeyedByBasedir, request );
          }
  
          copyScriptsToOutputDirectory( scriptFilesKeyedByBasedir, project.getBuild().getOutputDirectory(), request );
  
          return mojoDescriptors;
      }
  
      /**
       * @param scriptFilesKeyedByBasedir not null
       * @param outputDirectory not null
       * @param request the request
       * @throws ExtractionException if any
       */
      protected void copyScriptsToOutputDirectory( Map<String, Set<File>> scriptFilesKeyedByBasedir,
                                                   String outputDirectory, PluginToolsRequest request )
          throws ExtractionException
      {
          File outputDir = new File( outputDirectory );
  
          if ( !outputDir.exists() )
          {
              outputDir.mkdirs();
          }
  
          for ( Map.Entry<String, Set<File>> entry : scriptFilesKeyedByBasedir.entrySet() )
          {
              File sourceDir = new File( entry.getKey() );
 
             Set<File> scripts = entry.getValue();
 
             for ( File scriptFile : scripts )
             {
                 String relativePath = scriptFile.getPath().substring( sourceDir.getPath().length() );
 
                 if ( relativePath.charAt( 0 ) == File.separatorChar )
                 {
                     relativePath = relativePath.substring( 1 );
                 }
 
                 File outputFile = new File( outputDir, relativePath ).getAbsoluteFile();
 
                 if ( !outputFile.getParentFile().exists() )
                 {
                     outputFile.getParentFile().mkdirs();
                 }
 
                 try
                 {
                     FileUtils.copyFile( scriptFile, outputFile );
                 }
                 catch ( IOException e )
                 {
                     throw new ExtractionException(
                         "Cannot copy script file: " + scriptFile + " to output: " + outputFile, e );
                 }
             }
         }
     }
 
     /**
      * @param basedir not null
      * @param directories not null
      * @param scriptFileExtension not null
      * @param request the request
      * @return map with subdirs paths as key
      */
     protected Map<String, Set<File>> gatherFilesByBasedir( File basedir, List<String> directories,
                                                            String scriptFileExtension, PluginToolsRequest request )
     {
         Map<String, Set<File>> sourcesByBasedir = new TreeMap<>();
 
         for ( String resourceDir : directories )
         {
             Set<File> sources = new HashSet<>();
 
             getLogger().debug( "Scanning script dir: " + resourceDir + " with extractor: " + getClass().getName() );
             File dir = new File( resourceDir );
             if ( !dir.isAbsolute() )
             {
                 dir = new File( basedir, resourceDir ).getAbsoluteFile();
             }
 
             resourceDir = dir.getPath();
 
             if ( dir.exists() )
             {
                 DirectoryScanner scanner = new DirectoryScanner();
 
                 scanner.setBasedir( dir );
                 scanner.addDefaultExcludes();
                 scanner.setIncludes( new String[]{"**/*" + scriptFileExtension} );
                 scanner.scan();
 
                 String[] relativePaths = scanner.getIncludedFiles();
 
                 for ( String relativePath : relativePaths )
                 {
                     File scriptFile = new File( dir, relativePath ).getAbsoluteFile();
 
                     if ( scriptFile.isFile() && relativePath.endsWith( scriptFileExtension ) )
                     {
                         sources.add( scriptFile );
                     }
                 }
 
                 sourcesByBasedir.put( resourceDir, sources );
             }
         }
 
         return sourcesByBasedir;
     }
 
     /**
      * Should be implemented in the sub classes.
      *
      * @param metadataFilesByBasedir could be null
      * @param request The plugin request, never <code>null</code>.
      * @return always null
      * @throws ExtractionException if any
      * @throws InvalidPluginDescriptorException if any
      */
     protected List<MojoDescriptor> extractMojoDescriptorsFromMetadata( Map<String, Set<File>> metadataFilesByBasedir,
                                                                        PluginToolsRequest request )
         throws ExtractionException, InvalidPluginDescriptorException
     {
         return null;
     }
 
     /**
      * Should be implemented in the sub classes.
      * @param request the request
      * @return always null
      */
     protected String getMetadataFileExtension( PluginToolsRequest request )
     {
         return null;
     }
 
     /**
      * Should be implemented in the sub classes.
      *
      * @param scriptFilesKeyedByBasedir could be null
      * @param request The plugin request, never <code>null</code>.
      * @return always null
      * @throws ExtractionException if any
      * @throws InvalidPluginDescriptorException if any
      */
     protected List<MojoDescriptor> extractMojoDescriptors( Map<String, Set<File>> scriptFilesKeyedByBasedir,
                                                            PluginToolsRequest request )
         throws ExtractionException, InvalidPluginDescriptorException
     {
         return null;
     }
 
     /**
      * @param request the request
      * @return the file extension like <code>.bsh</code> for BeanShell.
      */
     protected abstract String getScriptFileExtension( PluginToolsRequest request );
 
 }