package org.apache.maven.plugins.help;

 /*

  * 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.FileInputStream;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.StringWriter;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Locale;

 import java.util.Map;

 import java.util.Properties;

 import java.util.TreeMap;

 import java.util.jar.JarEntry;

 import java.util.jar.JarInputStream;

 import org.apache.commons.lang.ClassUtils;

 import org.apache.maven.artifact.Artifact;

 import org.apache.maven.artifact.ArtifactUtils;

 import org.apache.maven.artifact.factory.ArtifactFactory;

 import org.apache.maven.artifact.repository.ArtifactRepository;

 import org.apache.maven.artifact.resolver.ArtifactNotFoundException;

 import org.apache.maven.artifact.resolver.ArtifactResolutionException;

 import org.apache.maven.artifact.resolver.ArtifactResolver;

 import org.apache.maven.execution.MavenSession;

 import org.apache.maven.model.Dependency;

 import org.apache.maven.model.Model;

 import org.apache.maven.model.io.xpp3.MavenXpp3Writer;

 import org.apache.maven.plugin.AbstractMojo;

 import org.apache.maven.plugin.MojoExecution;

 import org.apache.maven.plugin.MojoExecutionException;

 import org.apache.maven.plugin.MojoFailureException;

 import org.apache.maven.plugin.PluginParameterExpressionEvaluator;

 import org.apache.maven.plugin.descriptor.MojoDescriptor;

 import org.apache.maven.project.MavenProject;

 import org.apache.maven.project.MavenProjectBuilder;

 import org.apache.maven.project.ProjectBuildingException;

 import org.apache.maven.project.path.PathTranslator;

 import org.apache.maven.settings.Settings;

 import org.apache.maven.settings.io.xpp3.SettingsXpp3Writer;

 import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;

 import org.codehaus.plexus.components.interactivity.InputHandler;

 import org.codehaus.plexus.util.IOUtil;

 import org.codehaus.plexus.util.StringUtils;

 import com.thoughtworks.xstream.XStream;

 import com.thoughtworks.xstream.converters.MarshallingContext;

 import com.thoughtworks.xstream.converters.collections.PropertiesConverter;

 import com.thoughtworks.xstream.io.HierarchicalStreamWriter;

 /**

  * Evaluates Maven expressions given by the user in an interactive mode.

  *

  * @author <a href="mailto:vincent.siveton@gmail.com">Vincent Siveton</a>

  * @version $Id: EvaluateMojo.java 689794 2008-08-28 12:08:43Z vsiveton $

  * @since 2.1

  * @goal evaluate

  * @requiresProject false

  */

 public class EvaluateMojo

     extends AbstractMojo

 {

     // ----------------------------------------------------------------------

     // Mojo components

     // ----------------------------------------------------------------------

     /**

      * Maven Artifact Factory component.

      *

      * @component

      */

     private ArtifactFactory artifactFactory;

     /**

      * Input handler, needed for command line handling.

      *

      * @component

      */

     private InputHandler inputHandler;

     /**

      * Maven Project Builder component.

      *

      * @component

      */

     private MavenProjectBuilder mavenProjectBuilder;

     /**

      * @component

      */

     private PathTranslator pathTranslator;

     /**

      * Artifact Resolver component.

      *

      * @component

      */

     private ArtifactResolver resolver;

     // ----------------------------------------------------------------------

     // Mojo parameters

     // ----------------------------------------------------------------------

     /**

      * An artifact for evaluating Maven expressions.

      * <br/>

      * <b>Note</b>: Should respect the Maven format, i.e. <code>groupId:artifactId[:version][:classifier]</code>.

      *

      * @parameter expression="${artifact}"

      */

     private String artifact;

     /**

      * Local Repository.

      *

      * @parameter expression="${localRepository}"

      * @required

      * @readonly

      */

     protected ArtifactRepository localRepository;

     /**

      * The current Maven project or the super pom.

      *

      * @parameter expression="${project}"

      * @readonly

      * @required

      */

     protected MavenProject project;

     /**

      * Remote repositories used for the project.

      *

      * @parameter expression="${project.remoteArtifactRepositories}"

      * @readonly

      * @required

      */

     private List remoteRepositories;

     /**

      * The system settings for Maven.

      *

      * @parameter expression="${settings}"

      * @readonly

      * @required

      */

     protected Settings settings;

     /**

      * The current Maven session.

      *

      * @parameter expression="${session}"

      * @required

      * @readonly

      */

     private MavenSession session;

     // ----------------------------------------------------------------------

     // Instance variables

     // ----------------------------------------------------------------------

     /** lazy loading evaluator variable */

     private PluginParameterExpressionEvaluator evaluator;

     /** lazy loading xstream variable */

     private XStream xstream;

     // ----------------------------------------------------------------------

     // Public methods

     // ----------------------------------------------------------------------

     /** {@inheritDoc} */

     public void execute()

         throws MojoExecutionException, MojoFailureException

     {

         if ( !settings.isInteractiveMode() )

         {

             StringBuffer msg = new StringBuffer();

             msg.append( "Maven is configured to NOT interact with the user for input. " );

             msg.append( "This Mojo requires that 'interactiveMode' in your settings file is flag to 'true'." );

             getLog().error( msg.toString() );

             return;

         }

         validateParameters();

         if ( StringUtils.isNotEmpty( artifact ) )

         {

             Artifact artifactObj = getArtifact( artifact );

             try

             {

                 project = getMavenProject( artifactObj );

             }

             catch ( ProjectBuildingException e )

             {

                 throw new MojoExecutionException( "Unable to get the POM for the artifact '" + artifact

                     + "'. Verify the artifact parameter." );

             }

         }

         while ( true )

         {

             getLog().info( "Enter the Maven expression i.e. ${project.groupId} or 0 to exit?:" );

             try

             {

                 String userExpression = inputHandler.readLine();

                 if ( userExpression == null || userExpression.toLowerCase( Locale.ENGLISH ).equals( "0" ) )

                 {

                     break;

                 }

                 handleResponse( userExpression );

             }

             catch ( IOException e )

             {

                 throw new MojoExecutionException( "Unable to read from standard input.", e );

             }

         }

     }

     // ----------------------------------------------------------------------

     // Private methods

     // ----------------------------------------------------------------------

     /**

      * Validate Mojo parameters.

      */

     private void validateParameters()

     {

         if ( artifact == null )

         {

             // using project if found or super-pom

             getLog().info( "No artifact parameter specified, using '" + project.getId() + "' as project." );

         }

     }

     /**

      * @param artifactString should respect the format <code>groupId:artifactId[:version][:classifier]</code>

      * @return the <code>Artifact</code> object for the <code>artifactString</code> parameter.

      * @throws MojoExecutionException if the <code>artifactString</code> doesn't respect the format.

      */

     private Artifact getArtifact( String artifactString )

         throws MojoExecutionException

     {

         if ( StringUtils.isEmpty( artifactString ) )

         {

             throw new IllegalArgumentException( "artifact parameter could not be empty" );

         }

         String groupId = null; // required

         String artifactId = null; // required

         String version = null; // optional

         String classifier = null; // optional

         String[] artifactParts = artifactString.split( ":" );

         switch ( artifactParts.length )

         {

             case ( 2 ):

                 groupId = artifactParts[0];

                 artifactId = artifactParts[1];

                 version = Artifact.LATEST_VERSION;

                 break;

             case ( 3 ):

                 groupId = artifactParts[0];

                 artifactId = artifactParts[1];

                 version = artifactParts[2];

                 break;

             case ( 4 ):

                 groupId = artifactParts[0];

                 artifactId = artifactParts[1];

                 version = artifactParts[2];

                 classifier = artifactParts[3];

                 break;

             default:

                 throw new MojoExecutionException( "The artifact parameter '" + artifactString

                     + "' should be conform to: " + "'groupId:artifactId[:version][:classifier]'." );

         }

         if ( StringUtils.isNotEmpty( classifier ) )

         {

             return artifactFactory.createArtifactWithClassifier( groupId, artifactId, version, "jar", classifier );

         }

         return artifactFactory.createArtifact( groupId, artifactId, version, Artifact.SCOPE_COMPILE, "jar" );

     }

     /**

      * @param artifactObj not null

      * @return the POM for the given artifact.

      * @throws MojoExecutionException if the artifact has a system scope.

      * @throws ProjectBuildingException when building pom.

      */

     private MavenProject getMavenProject( Artifact artifactObj )

         throws MojoExecutionException, ProjectBuildingException

     {

         if ( Artifact.SCOPE_SYSTEM.equals( artifactObj.getScope() ) )

         {

             throw new MojoExecutionException( "System artifact is not be handled." );

         }

         Artifact copyArtifact = ArtifactUtils.copyArtifact( artifactObj );

         if ( !"pom".equals( copyArtifact.getType() ) )

         {

             copyArtifact =

                 artifactFactory.createProjectArtifact( copyArtifact.getGroupId(), copyArtifact.getArtifactId(),

                                                        copyArtifact.getVersion(), copyArtifact.getScope() );

         }

         return mavenProjectBuilder.buildFromRepository( copyArtifact, remoteRepositories, localRepository );

     }

     /**

      * @return a lazy loading evaluator object.

      * @throws MojoExecutionException if any

      * @throws MojoFailureException if any reflection exceptions occur or missing components.

      * @see #getMojoDescriptor(String, MavenSession, MavenProject, String, boolean, boolean)

      */

     private PluginParameterExpressionEvaluator getEvaluator()

         throws MojoExecutionException, MojoFailureException

     {

         if ( evaluator == null )

         {

             MojoDescriptor mojoDescriptor =

                 HelpUtil.getMojoDescriptor( "help:evaluate", session, project, "help:evaluate", true, false );

             MojoExecution mojoExecution = new MojoExecution( mojoDescriptor );

             evaluator =

                 new PluginParameterExpressionEvaluator( session, mojoExecution, pathTranslator,

                                                         session.getContainer().getLogger(), project,

                                                         session.getExecutionProperties() );

         }

         return evaluator;

     }

     /**

      * @param expression the user expression asked.

      * @throws MojoExecutionException if any

      * @throws MojoFailureException if any reflection exceptions occur or missing components.

      */

     private void handleResponse( String expression )

         throws MojoExecutionException, MojoFailureException

     {

         StringBuffer response = new StringBuffer();

         Object obj;

         try

         {

             obj = getEvaluator().evaluate( expression );

         }

         catch ( ExpressionEvaluationException e )

         {

             throw new MojoExecutionException( "Error when evaluating the Maven expression", e );

         }

         if ( obj != null && expression.equals( obj.toString() ) )

         {

             getLog().warn( "The Maven expression was invalid. Please use a valid expression." );

             return;

         }

         // handle null

         if ( obj == null )

         {

             response.append( "null object or invalid expression" );

         }

         // handle primitives objects

         else if ( obj instanceof String )

         {

             response.append( obj.toString() );

         }

         else if ( obj instanceof Boolean )

         {

             response.append( obj.toString() );

         }

         else if ( obj instanceof Byte )

         {

             response.append( obj.toString() );

         }

         else if ( obj instanceof Character )

         {

             response.append( obj.toString() );

         }

         else if ( obj instanceof Double )

         {

             response.append( obj.toString() );

         }

         else if ( obj instanceof Float )

         {

             response.append( obj.toString() );

         }

         else if ( obj instanceof Integer )

         {

             response.append( obj.toString() );

         }

         else if ( obj instanceof Long )

         {

             response.append( obj.toString() );

         }

         else if ( obj instanceof Short )

         {

             response.append( obj.toString() );

         }

         // handle specific objects

         else if ( obj instanceof File )

         {

             File f = (File) obj;

             response.append( f.getAbsolutePath() );

         }

         // handle Maven pom object

         else if ( obj instanceof MavenProject )

         {

             MavenProject projectAsked = (MavenProject) obj;

             StringWriter sWriter = new StringWriter();

             MavenXpp3Writer pomWriter = new MavenXpp3Writer();

             try

             {

                 pomWriter.write( sWriter, projectAsked.getModel() );

             }

             catch ( IOException e )

             {

                 throw new MojoExecutionException( "Error when writing pom", e );

             }

             response.append( sWriter.toString() );

         }

         // handle Maven Settings object

         else if ( obj instanceof Settings )

         {

             Settings settingsAsked = (Settings) obj;

             StringWriter sWriter = new StringWriter();

             SettingsXpp3Writer settingsWriter = new SettingsXpp3Writer();

             try

             {

                 settingsWriter.write( sWriter, settingsAsked );

             }

             catch ( IOException e )

             {

                 throw new MojoExecutionException( "Error when writing settings", e );

             }

             response.append( sWriter.toString() );

         }

         else

         {

             // others Maven objects

             response.append( toXML( expression, obj ) );

         }

         getLog().info( "\n" + response.toString() );

     }

     /**

      * @param expression the user expression.

      * @param obj a not null.

      * @return the XML for the given object.

      */

     private String toXML( String expression, Object obj )

     {

         XStream currentXStream = getXStream();

         // beautify list

         if ( obj instanceof List )

         {

             List list = (List) obj;

             if ( list.size() > 0 )

             {

                 Object elt = list.iterator().next();

                 String name = StringUtils.lowercaseFirstLetter( ClassUtils.getShortClassName( elt.getClass() ) );

                 currentXStream.alias( pluralize( name ), List.class );

             }

             else

             {

                 // try to detect the alias from question

                 if ( expression.indexOf( "." ) != -1 )

                 {

                     String name = expression.substring( expression.indexOf( "." ) + 1, expression.indexOf( "}" ) );

                     currentXStream.alias( name, List.class );

                 }

             }

         }

         return currentXStream.toXML( obj );

     }

     /**

      * @return lazy loading xstream object.

      */

     private XStream getXStream()

     {

         if ( xstream == null )

         {

             xstream = new XStream();

             addAlias( xstream );

             // handle Properties a la Maven

             xstream.registerConverter( new PropertiesConverter()

             {

                 /** {@inheritDoc} */

                 public boolean canConvert( Class type )

                 {

                     return Properties.class == type;

                 }

                 /** {@inheritDoc} */

                 public void marshal( Object source, HierarchicalStreamWriter writer, MarshallingContext context )

                 {

                     Properties properties = (Properties) source;

                     Map map = new TreeMap( properties ); // sort

                     for ( Iterator iterator = map.entrySet().iterator(); iterator.hasNext(); )

                     {

                         Map.Entry entry = (Map.Entry) iterator.next();

                         writer.startNode( entry.getKey().toString() );

                         writer.setValue( entry.getValue().toString() );

                         writer.endNode();

                     }

                 }

             } );

         }

         return xstream;

     }

     /**

      * @param xstreamObject not null

      */

     private void addAlias( XStream xstreamObject )

     {

         try

         {

             addAlias( xstreamObject, getMavenModelJarFile(), "org.apache.maven.model" );

             addAlias( xstreamObject, getMavenSettingsJarFile(), "org.apache.maven.settings" );

         }

         catch ( MojoExecutionException e )

         {

             if ( getLog().isDebugEnabled() )

             {

                 getLog().debug( "MojoExecutionException: " + e.getMessage(), e );

             }

         }

         catch ( ArtifactResolutionException e )

         {

             if ( getLog().isDebugEnabled() )

             {

                 getLog().debug( "ArtifactResolutionException: " + e.getMessage(), e );

             }

         }

         catch ( ArtifactNotFoundException e )

         {

             if ( getLog().isDebugEnabled() )

             {

                 getLog().debug( "ArtifactNotFoundException: " + e.getMessage(), e );

             }

         }

         catch ( ProjectBuildingException e )

         {

             if ( getLog().isDebugEnabled() )

             {

                 getLog().debug( "ProjectBuildingException: " + e.getMessage(), e );

             }

         }

         // TODO need to handle specific Maven objects like DefaultArtifact?

     }

     /**

      * @param xstreamObject not null

      * @param jarFile not null

      * @param packageFilter a package name to filter.

      */

     private void addAlias( XStream xstreamObject, File jarFile, String packageFilter )

     {

         JarInputStream jarStream = null;

         try

         {

             jarStream = new JarInputStream( new FileInputStream( jarFile ) );

             JarEntry jarEntry = jarStream.getNextJarEntry();

             while ( jarEntry != null )

             {

                 if ( jarEntry == null )

                 {

                     break;

                 }

                 if ( jarEntry.getName().toLowerCase( Locale.ENGLISH ).endsWith( ".class" ) )

                 {

                     String name = jarEntry.getName().substring( 0, jarEntry.getName().indexOf( "." ) );

                     name = name.replaceAll( "/", "\\." );

                     if ( name.indexOf( packageFilter ) != -1 )

                     {

                         try

                         {

                             Class clazz = ClassUtils.getClass( name );

                             String alias = StringUtils.lowercaseFirstLetter( ClassUtils.getShortClassName( clazz ) );

                             xstreamObject.alias( alias, clazz );

                             if ( !clazz.equals( Model.class ) )

                             {

                                 xstreamObject.omitField( clazz, "modelEncoding" ); // unnecessary field

                             }

                         }

                         catch ( ClassNotFoundException e )

                         {

                             e.printStackTrace();

                         }

                     }

                 }

                 jarStream.closeEntry();

                 jarEntry = jarStream.getNextJarEntry();

             }

         }

         catch ( IOException e )

         {

             if ( getLog().isDebugEnabled() )

             {

                 getLog().debug( "IOException: " + e.getMessage(), e );

             }

         }

         finally

         {

             IOUtil.close( jarStream );

         }

     }

     /**

      * @return the <code>org.apache.maven:maven-model</code> artifact jar file in the local repository.

      * @throws MojoExecutionException if any

      * @throws ProjectBuildingException if any

      * @throws ArtifactResolutionException if any

      * @throws ArtifactNotFoundException if any

      */

     private File getMavenModelJarFile()

         throws MojoExecutionException, ProjectBuildingException, ArtifactResolutionException,

         ArtifactNotFoundException

     {

         return getArtifactFile( true );

     }

     /**

      * @return the <code>org.apache.maven:maven-settings</code> artifact jar file in the local repository.

      * @throws MojoExecutionException if any

      * @throws ProjectBuildingException if any

      * @throws ArtifactResolutionException if any

      * @throws ArtifactNotFoundException if any

      */

     private File getMavenSettingsJarFile()

         throws MojoExecutionException, ProjectBuildingException, ArtifactResolutionException,

         ArtifactNotFoundException

     {

         return getArtifactFile( false );

     }

     /**

      *

      * @param isPom <code>true</code> to lookup the <code>maven-model</code> artifact jar, <code>false</code> to

      * lookup the <code>maven-settings</code> artifact jar.

      * @return the <code>org.apache.maven:maven-model|maven-settings</code> artifact jar file for this current

      * HelpPlugin pom.

      * @throws MojoExecutionException if any

      * @throws ProjectBuildingException if any

      * @throws ArtifactResolutionException if any

      * @throws ArtifactNotFoundException if any

      */

     private File getArtifactFile( boolean isPom )

         throws MojoExecutionException, ProjectBuildingException, ArtifactResolutionException,

         ArtifactNotFoundException

     {

         for ( Iterator it = getHelpPluginPom().getDependencies().iterator(); it.hasNext(); )

         {

             Dependency depependency = (Dependency) it.next();

             if ( !( depependency.getGroupId().equals( "org.apache.maven" ) ) )

             {

                 continue;

             }

             if ( isPom )

             {

                 if ( !( depependency.getArtifactId().equals( "maven-model" ) ) )

                 {

                     continue;

                 }

             }

             else

             {

                 if ( !( depependency.getArtifactId().equals( "maven-settings" ) ) )

                 {

                     continue;

                 }

             }

             Artifact mavenArtifact =

                 getArtifact( depependency.getGroupId() + ":" + depependency.getArtifactId() + ":"

                     + depependency.getVersion() );

             resolver.resolveAlways( mavenArtifact, remoteRepositories, localRepository );

             return mavenArtifact.getFile();

         }

         throw new MojoExecutionException( "Unable to find the 'org.apache.maven:"

             + ( isPom ? "maven-model" : "maven-settings" ) + "' artifact" );

     }

     /**

      * @return the Maven POM for the current help plugin

      * @throws MojoExecutionException if any

      * @throws ProjectBuildingException if any

      */

     private MavenProject getHelpPluginPom()

         throws MojoExecutionException, ProjectBuildingException

     {

         String resource = "META-INF/maven/org.apache.maven.plugins/maven-help-plugin/pom.properties";

         InputStream resourceAsStream = EvaluateMojo.class.getClassLoader().getResourceAsStream( resource );

         Artifact helpPluginArtifact = null;

         if ( resourceAsStream != null )

         {

             Properties properties = new Properties();

             try

             {

                 properties.load( resourceAsStream );

             }

             catch ( IOException e )

             {

                 if ( getLog().isDebugEnabled() )

                 {

                     getLog().debug( "IOException: " + e.getMessage(), e );

                 }

             }

             String artifactString =

                 properties.getProperty( "groupId", "unknown" ) + ":"

                     + properties.getProperty( "artifactId", "unknown" ) + ":"

                     + properties.getProperty( "version", "unknown" );

             helpPluginArtifact = getArtifact( artifactString );

         }

         if ( helpPluginArtifact == null )

         {

             throw new MojoExecutionException( "The help plugin artifact was not found." );

         }

         return getMavenProject( helpPluginArtifact );

     }

     /**

      * @param name not null

      * @return the plural of the name

      */

     private static String pluralize( String name )

     {

         if ( StringUtils.isEmpty( name ) )

         {

             throw new IllegalArgumentException( "name is required" );

         }

         if ( name.endsWith( "y" ) )

         {

             return name.substring( 0, name.length() - 1 ) + "ies";

         }

         else if ( name.endsWith( "s" ) )

         {

             return name;

         }

         else

         {

             return name + "s";

         }

     }

 }