package org.codehaus.mojo.gwt.shell;
   
   /*
    * 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 org.apache.commons.io.FilenameUtils;
  import org.apache.commons.lang.SystemUtils;
  import org.apache.maven.artifact.Artifact;
  import org.apache.maven.model.Resource;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.plugins.annotations.Component;
  import org.apache.maven.plugins.annotations.LifecyclePhase;
  import org.apache.maven.plugins.annotations.Mojo;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.codehaus.plexus.util.IOUtil;
  import org.codehaus.plexus.util.cli.StreamConsumer;
  import org.sonatype.plexus.build.incremental.BuildContext;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.OutputStreamWriter;
  import java.nio.charset.Charset;
  
  /**
   * Creates CSS interfaces for css files.
   * Will use the utility tool provided in gwt sdk which create a corresponding Java interface for accessing 
   * the classnames used in the file.
   *
   * @author <a href="mailto:undheim@corporater.com">Stale Undheim</a>
   * @author olamy
   * @since 2.1.0-1
   */
  @Mojo(name = "css", defaultPhase = LifecyclePhase.GENERATE_SOURCES, threadSafe = true)
  public class CSSMojo
      extends AbstractGwtShellMojo
  {
      /**
       * List of resourceBundles that should be used to generate CSS interfaces.
       */
      @Parameter
      private String[] cssFiles;
  
      /**
       * Shortcut for a single cssFile
       */
      @Parameter
      private String cssFile;
  
      @Parameter(property = "project.build.sourceEncoding")
      private String encoding;
  
      @Component
      private BuildContext buildContext;
  
      @Override
      protected boolean isGenerator() {
          return true;
      }
  
      public void doExecute()
          throws MojoExecutionException, MojoFailureException
      {
          setup();
  
          // java -cp gwt-dev.jar:gwt-user.jar
          // com.google.gwt.resources.css.InterfaceGenerator -standalone -typeName some.package.MyCssResource -css
          // input.css
          if ( cssFiles != null )
          {
              for ( String file : cssFiles )
              {
                  final String typeName = FilenameUtils.separatorsToSystem( file ).
                      substring( 0, file.lastIndexOf( '.' ) ).replace( File.separatorChar, '.' );
                  final File javaOutput =
                      new File( getGenerateDirectory(), typeName.replace( '.', File.separatorChar ) + ".java" );
                  for ( Resource resource : getProject().getResources() )
                  {
                      final File candidate = new File( resource.getDirectory(), file );
                      if ( candidate.exists() )
                      {
                          if ( buildContext.isUptodate( javaOutput, candidate ) )
                          {
                             getLog().debug( javaOutput.getAbsolutePath() + " is up to date. Generation skipped" );
                             break;
                         }
 
                         getLog().info( "Generating " + javaOutput + " with typeName " + typeName );
                         ensureTargetPackageExists( getGenerateDirectory(), typeName );
 
                         
                         try
                         {
                             final StringBuilder content = new StringBuilder();
                             createJavaCommand()
                                 .setMainClass( "com.google.gwt.resources.css.InterfaceGenerator" )
                                 .addToClasspath( getClasspath( Artifact.SCOPE_COMPILE ) )
                                 .arg( "-standalone" )
                                 .arg( "-typeName" )
                                 .arg( typeName )
                                 .arg( "-css" )
                                 .arg( candidate.getAbsolutePath() )
                                 .addToClasspath( getJarFiles(GWT_DEV, false) )
                                 .addToClasspath( getJarFiles(GWT_USER, false) )
                                 .setOut( new StreamConsumer()
                                     {
                                         public void consumeLine( String line )
                                         {
                                             content.append( line ).append( SystemUtils.LINE_SEPARATOR );
                                         }
                                     } )
                                 .execute();
                             if ( content.length() == 0 )
                             {
                                 throw new MojoExecutionException( "cannot generate java source from file " + file + "." );
                             }
                             final OutputStreamWriter outputWriter =
                                 new OutputStreamWriter( buildContext.newFileOutputStream( javaOutput ) , encoding );
                             try {
                                 outputWriter.write( content.toString() );
                             } finally {
                                 IOUtil.close( outputWriter );
                             }
                         }
                         catch ( IOException e )
                         {
                             throw new MojoExecutionException( "Failed to write to file: " + javaOutput, e );
                         }
                         catch ( JavaCommandException e )
                         {
                             throw new MojoExecutionException( e.getMessage(), e );
                         }
                         break;
                     }
                 }
             }
         }
     }
 
     private void setup()
     {
         setupGenerateDirectory();
 
         if ( encoding == null )
         {
             getLog().warn( "Encoding is not set, your build will be platform dependent" );
             encoding = Charset.defaultCharset().name();
         }
 
         if ( cssFiles == null && cssFile != null )
         {
             cssFiles = new String[] { cssFile };
         }
     }
 
     private void ensureTargetPackageExists( File generateDirectory, String targetName )
     {
         targetName = targetName.contains( "." ) ? targetName.substring( 0, targetName.lastIndexOf( '.' ) ) : targetName;
         String targetPackage = targetName.replace( '.', File.separatorChar );
         getLog().debug( "ensureTargetPackageExists, targetName : " + targetName + ", targetPackage : " + targetPackage );
         File targetPackageDirectory = new File( generateDirectory, targetPackage );
         if ( !targetPackageDirectory.exists() )
         {
             targetPackageDirectory.mkdirs();
         }
     }
 
 }