/*
    *   Copyright (C) 2005 Christian Schulte <cs@schulte.it>
    *   All rights reserved.
    *
    *   Redistribution and use in source and binary forms, with or without
    *   modification, are permitted provided that the following conditions
    *   are met:
    *
    *     o Redistributions of source code must retain the above copyright
   *       notice, this list of conditions and the following disclaimer.
   *
   *     o Redistributions in binary form must reproduce the above copyright
   *       notice, this list of conditions and the following disclaimer in
   *       the documentation and/or other materials provided with the
   *       distribution.
   *
   *   THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
   *   INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
   *   AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
   *   THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY DIRECT, INDIRECT,
   *   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   *   NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   *   THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   *   $JOMC: MergeModletsTask.java 5263 2016-05-01 23:44:12Z schulte $
   *
   */
  package org.jomc.ant;
  
  import java.io.ByteArrayOutputStream;
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStreamWriter;
  import java.net.HttpURLConnection;
  import java.net.SocketTimeoutException;
  import java.net.URISyntaxException;
  import java.net.URL;
  import java.net.URLConnection;
  import java.util.ArrayList;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Set;
  import java.util.logging.Level;
  import javax.xml.bind.JAXBElement;
  import javax.xml.bind.JAXBException;
  import javax.xml.bind.Marshaller;
  import javax.xml.bind.Unmarshaller;
  import javax.xml.bind.util.JAXBResult;
  import javax.xml.bind.util.JAXBSource;
  import javax.xml.transform.Source;
  import javax.xml.transform.Transformer;
  import javax.xml.transform.TransformerConfigurationException;
  import javax.xml.transform.TransformerException;
  import javax.xml.transform.stream.StreamSource;
  import org.apache.tools.ant.BuildException;
  import org.apache.tools.ant.Project;
  import org.jomc.ant.types.ModletResourceType;
  import org.jomc.ant.types.NameType;
  import org.jomc.ant.types.ResourceType;
  import org.jomc.ant.types.TransformerResourceType;
  import org.jomc.modlet.DefaultModletProvider;
  import org.jomc.modlet.ModelContext;
  import org.jomc.modlet.ModelException;
  import org.jomc.modlet.ModelValidationReport;
  import org.jomc.modlet.Modlet;
  import org.jomc.modlet.ModletObject;
  import org.jomc.modlet.Modlets;
  import org.jomc.modlet.ObjectFactory;
  
  /**
   * Task for merging modlet resources.
   *
   * @author <a href="mailto:cs@schulte.it">Christian Schulte</a>
   * @version $JOMC: MergeModletsTask.java 5263 2016-05-01 23:44:12Z schulte $
   */
  public final class MergeModletsTask extends JomcTask
  {
  
      /**
       * The encoding of the modlet resource.
       */
      private String modletEncoding;
  
      /**
       * File to write the merged modlet to.
       */
      private File modletFile;
  
      /**
       * The name of the merged modlet.
       */
      private String modletName;
  
     /**
      * The version of the merged modlet.
      */
     private String modletVersion;
 
     /**
      * The vendor of the merged modlet.
      */
     private String modletVendor;
 
     /**
      * Resources to merge.
      */
     private Set<ModletResourceType> modletResources;
 
     /**
      * Included modlets.
      */
     private Set<NameType> modletIncludes;
 
     /**
      * Excluded modlets.
      */
     private Set<NameType> modletExcludes;
 
     /**
      * XSLT documents to use for transforming modlet objects.
      */
     private List<TransformerResourceType> modletObjectStylesheetResources;
 
     /**
      * Creates a new {@code MergeModletsTask} instance.
      */
     public MergeModletsTask()
     {
         super();
     }
 
     /**
      * Gets the file to write the merged modlet to.
      *
      * @return The file to write the merged modlet to or {@code null}.
      *
      * @see #setModletFile(java.io.File)
      */
     public File getModletFile()
     {
         return this.modletFile;
     }
 
     /**
      * Sets the file to write the merged modlet to.
      *
      * @param value The new file to write the merged modlet to or {@code null}.
      *
      * @see #getModletFile()
      */
     public void setModletFile( final File value )
     {
         this.modletFile = value;
     }
 
     /**
      * Gets the encoding of the modlet resource.
      *
      * @return The encoding of the modlet resource.
      *
      * @see #setModletEncoding(java.lang.String)
      */
     public String getModletEncoding()
     {
         if ( this.modletEncoding == null )
         {
             this.modletEncoding = new OutputStreamWriter( new ByteArrayOutputStream() ).getEncoding();
         }
 
         return this.modletEncoding;
     }
 
     /**
      * Sets the encoding of the modlet resource.
      *
      * @param value The new encoding of the modlet resource or {@code null}.
      *
      * @see #getModletEncoding()
      */
     public void setModletEncoding( final String value )
     {
         this.modletEncoding = value;
     }
 
     /**
      * Gets the name of the merged modlet.
      *
      * @return The name of the merged modlet or {@code null}.
      *
      * @see #setModletName(java.lang.String)
      */
     public String getModletName()
     {
         return this.modletName;
     }
 
     /**
      * Sets the name of the merged modlet.
      *
      * @param value The new name of the merged modlet or {@code null}.
      *
      * @see #getModletName()
      */
     public void setModletName( final String value )
     {
         this.modletName = value;
     }
 
     /**
      * Gets the version of the merged modlet.
      *
      * @return The version of the merged modlet or {@code null}.
      *
      * @see #setModletVersion(java.lang.String)
      */
     public String getModletVersion()
     {
         return this.modletVersion;
     }
 
     /**
      * Sets the version of the merged modlet.
      *
      * @param value The new version of the merged modlet or {@code null}.
      *
      * @see #getModletVersion()
      */
     public void setModletVersion( final String value )
     {
         this.modletVersion = value;
     }
 
     /**
      * Gets the vendor of the merged modlet.
      *
      * @return The vendor of the merge modlet or {@code null}.
      *
      * @see #setModletVendor(java.lang.String)
      */
     public String getModletVendor()
     {
         return this.modletVendor;
     }
 
     /**
      * Sets the vendor of the merged modlet.
      *
      * @param value The new vendor of the merged modlet or {@code null}.
      *
      * @see #getModletVendor()
      */
     public void setModletVendor( final String value )
     {
         this.modletVendor = value;
     }
 
     /**
      * Gets a set of resource names to merge.
      * <p>
      * This accessor method returns a reference to the live set, not a snapshot. Therefore any modification you make
      * to the returned set will be present inside the object. This is why there is no {@code set} method for the
      * modlet resources property.
      * </p>
      *
      * @return A set of names of resources to merge.
      *
      * @see #createModletResource()
      */
     public Set<ModletResourceType> getModletResources()
     {
         if ( this.modletResources == null )
         {
             this.modletResources = new HashSet<ModletResourceType>();
         }
 
         return this.modletResources;
     }
 
     /**
      * Creates a new {@code modletResource} element instance.
      *
      * @return A new {@code modletResource} element instance.
      *
      * @see #getModletResources()
      */
     public ModletResourceType createModletResource()
     {
         final ModletResourceType modletResource = new ModletResourceType();
         this.getModletResources().add( modletResource );
         return modletResource;
     }
 
     /**
      * Gets a set of modlet names to include.
      * <p>
      * This accessor method returns a reference to the live set, not a snapshot. Therefore any modification you make
      * to the returned set will be present inside the object. This is why there is no {@code set} method for the
      * modlet includes property.
      * </p>
      *
      * @return A set of modlet names to include.
      *
      * @see #createModletInclude()
      */
     public Set<NameType> getModletIncludes()
     {
         if ( this.modletIncludes == null )
         {
             this.modletIncludes = new HashSet<NameType>();
         }
 
         return this.modletIncludes;
     }
 
     /**
      * Creates a new {@code modletInclude} element instance.
      *
      * @return A new {@code modletInclude} element instance.
      *
      * @see #getModletIncludes()
      */
     public NameType createModletInclude()
     {
         final NameType modletInclude = new NameType();
         this.getModletIncludes().add( modletInclude );
         return modletInclude;
     }
 
     /**
      * Gets a set of modlet names to exclude.
      * <p>
      * This accessor method returns a reference to the live set, not a snapshot. Therefore any modification you make
      * to the returned set will be present inside the object. This is why there is no {@code set} method for the
      * modlet excludes property.
      * </p>
      *
      * @return A set of modlet names to exclude.
      *
      * @see #createModletExclude()
      */
     public Set<NameType> getModletExcludes()
     {
         if ( this.modletExcludes == null )
         {
             this.modletExcludes = new HashSet<NameType>();
         }
 
         return this.modletExcludes;
     }
 
     /**
      * Creates a new {@code modletExclude} element instance.
      *
      * @return A new {@code modletExclude} element instance.
      *
      * @see #getModletExcludes()
      */
     public NameType createModletExclude()
     {
         final NameType modletExclude = new NameType();
         this.getModletExcludes().add( modletExclude );
         return modletExclude;
     }
 
     /**
      * Gets the XSLT documents to use for transforming modlet objects.
      * <p>
      * This accessor method returns a reference to the live list, not a snapshot. Therefore any modification you make
      * to the returned list will be present inside the object. This is why there is no {@code set} method for the
      * modlet object stylesheet resources property.
      * </p>
      *
      * @return The XSLT documents to use for transforming modlet objects.
      *
      * @see #createModletObjectStylesheetResource()
      */
     public List<TransformerResourceType> getModletObjectStylesheetResources()
     {
         if ( this.modletObjectStylesheetResources == null )
         {
             this.modletObjectStylesheetResources = new LinkedList<TransformerResourceType>();
         }
 
         return this.modletObjectStylesheetResources;
     }
 
     /**
      * Creates a new {@code modletObjectStylesheetResource} element instance.
      *
      * @return A new {@code modletObjectStylesheetResource} element instance.
      *
      * @see #getModletObjectStylesheetResources()
      */
     public TransformerResourceType createModletObjectStylesheetResource()
     {
         final TransformerResourceType modletObjectStylesheetResource = new TransformerResourceType();
         this.getModletObjectStylesheetResources().add( modletObjectStylesheetResource );
         return modletObjectStylesheetResource;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void preExecuteTask() throws BuildException
     {
         super.preExecuteTask();
 
         this.assertNotNull( "modletFile", this.getModletFile() );
         this.assertNotNull( "modletName", this.getModletName() );
         this.assertNamesNotNull( this.getModletExcludes() );
         this.assertNamesNotNull( this.getModletIncludes() );
         this.assertLocationsNotNull( this.getModletResources() );
         this.assertLocationsNotNull( this.getModletObjectStylesheetResources() );
     }
 
     /**
      * Merges modlet resources.
      *
      * @throws BuildException if merging modlet resources fails.
      */
     @Override
     public void executeTask() throws BuildException
     {
         ProjectClassLoader classLoader = null;
 
         try
         {
             this.log( Messages.getMessage( "mergingModlets", this.getModel() ) );
 
             classLoader = this.newProjectClassLoader();
             final Modlets modlets = new Modlets();
             final Set<ResourceType> resources = new HashSet<ResourceType>( this.getModletResources() );
             final ModelContext context = this.newModelContext( classLoader );
             final Marshaller marshaller = context.createMarshaller( ModletObject.MODEL_PUBLIC_ID );
             final Unmarshaller unmarshaller = context.createUnmarshaller( ModletObject.MODEL_PUBLIC_ID );
 
             if ( this.isModletResourceValidationEnabled() )
             {
                 unmarshaller.setSchema( context.createSchema( ModletObject.MODEL_PUBLIC_ID ) );
             }
 
             if ( resources.isEmpty() )
             {
                 final ResourceType defaultResource = new ResourceType();
                 defaultResource.setLocation( DefaultModletProvider.getDefaultModletLocation() );
                 defaultResource.setOptional( true );
                 resources.add( defaultResource );
             }
 
             for ( final ResourceType resource : resources )
             {
                 final URL[] urls = this.getResources( context, resource.getLocation() );
 
                 if ( urls.length == 0 )
                 {
                     if ( resource.isOptional() )
                     {
                         this.logMessage( Level.WARNING, Messages.getMessage( "modletResourceNotFound",
                                                                              resource.getLocation() ) );
 
                     }
                     else
                     {
                         throw new BuildException( Messages.getMessage( "modletResourceNotFound",
                                                                        resource.getLocation() ) );
 
                     }
                 }
 
                 for ( int i = urls.length - 1; i >= 0; i-- )
                 {
                     InputStream in = null;
                     URLConnection con = null;
 
                     try
                     {
                         this.logMessage( Level.FINEST, Messages.getMessage( "reading", urls[i].toExternalForm() ) );
 
                         con = urls[i].openConnection();
                         con.setConnectTimeout( resource.getConnectTimeout() );
                         con.setReadTimeout( resource.getReadTimeout() );
                         con.connect();
                         in = con.getInputStream();
 
                         final Source source = new StreamSource( in, urls[i].toURI().toASCIIString() );
                         Object o = unmarshaller.unmarshal( source );
                         if ( o instanceof JAXBElement<?> )
                         {
                             o = ( (JAXBElement<?>) o ).getValue();
                         }
 
                         if ( o instanceof Modlet )
                         {
                             modlets.getModlet().add( (Modlet) o );
                         }
                         else if ( o instanceof Modlets )
                         {
                             modlets.getModlet().addAll( ( (Modlets) o ).getModlet() );
                         }
                         else
                         {
                             this.logMessage( Level.WARNING, Messages.getMessage( "unsupportedModletResource",
                                                                                  urls[i].toExternalForm() ) );
 
                         }
 
                         in.close();
                         in = null;
                     }
                     catch ( final SocketTimeoutException e )
                     {
                         String message = Messages.getMessage( e );
                         message = Messages.getMessage( "resourceTimeout", message != null ? " " + message : "" );
 
                         if ( resource.isOptional() )
                         {
                             this.getProject().log( message, e, Project.MSG_WARN );
                         }
                         else
                         {
                             throw new BuildException( message, e, this.getLocation() );
                         }
                     }
                     catch ( final IOException e )
                     {
                         String message = Messages.getMessage( e );
                         message = Messages.getMessage( "resourceFailure", message != null ? " " + message : "" );
 
                         if ( resource.isOptional() )
                         {
                             this.getProject().log( message, e, Project.MSG_WARN );
                         }
                         else
                         {
                             throw new BuildException( message, e, this.getLocation() );
                         }
                     }
                     finally
                     {
                         try
                         {
                             if ( in != null )
                             {
                                 in.close();
                             }
                         }
                         catch ( final IOException e )
                         {
                             this.logMessage( Level.SEVERE, Messages.getMessage( e ), e );
                         }
                         finally
                         {
                             if ( con instanceof HttpURLConnection )
                             {
                                 ( (HttpURLConnection) con ).disconnect();
                             }
                         }
                     }
                 }
             }
 
             for ( final Iterator<Modlet> it = modlets.getModlet().iterator(); it.hasNext(); )
             {
                 final Modlet modlet = it.next();
 
                 if ( !this.isModletIncluded( modlet ) || this.isModletExcluded( modlet ) )
                 {
                     it.remove();
                     this.log( Messages.getMessage( "excludingModlet", modlet.getName() ) );
                 }
                 else
                 {
                     this.log( Messages.getMessage( "includingModlet", modlet.getName() ) );
                 }
             }
 
             final ModelValidationReport validationReport =
                 context.validateModel( ModletObject.MODEL_PUBLIC_ID,
                                        new JAXBSource( marshaller, new ObjectFactory().createModlets( modlets ) ) );
 
             this.logValidationReport( context, validationReport );
 
             if ( !validationReport.isModelValid() )
             {
                 throw new ModelException( Messages.getMessage( "invalidModel", ModletObject.MODEL_PUBLIC_ID ) );
             }
 
             Modlet mergedModlet = modlets.getMergedModlet( this.getModletName(), this.getModel() );
             mergedModlet.setVendor( this.getModletVendor() );
             mergedModlet.setVersion( this.getModletVersion() );
 
             for ( int i = 0, s0 = this.getModletObjectStylesheetResources().size(); i < s0; i++ )
             {
                 final Transformer transformer =
                     this.getTransformer( this.getModletObjectStylesheetResources().get( i ) );
 
                 if ( transformer != null )
                 {
                     final JAXBSource source =
                         new JAXBSource( marshaller, new ObjectFactory().createModlet( mergedModlet ) );
 
                     final JAXBResult result = new JAXBResult( unmarshaller );
                     transformer.transform( source, result );
 
                     if ( result.getResult() instanceof JAXBElement<?>
                              && ( (JAXBElement<?>) result.getResult() ).getValue() instanceof Modlet )
                     {
                         mergedModlet = (Modlet) ( (JAXBElement<?>) result.getResult() ).getValue();
                     }
                     else
                     {
                         throw new BuildException( Messages.getMessage(
                             "illegalTransformationResult",
                             this.getModletObjectStylesheetResources().get( i ).getLocation() ), this.getLocation() );
 
                     }
                 }
             }
 
             this.log( Messages.getMessage( "writingEncoded", this.getModletFile().getAbsolutePath(),
                                            this.getModletEncoding() ) );
 
             marshaller.setProperty( Marshaller.JAXB_ENCODING, this.getModletEncoding() );
             marshaller.setProperty( Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE );
             marshaller.setSchema( context.createSchema( ModletObject.MODEL_PUBLIC_ID ) );
             marshaller.marshal( new ObjectFactory().createModlet( mergedModlet ), this.getModletFile() );
 
             classLoader.close();
             classLoader = null;
         }
         catch ( final IOException e )
         {
             throw new BuildException( Messages.getMessage( e ), e, this.getLocation() );
         }
         catch ( final URISyntaxException e )
         {
             throw new BuildException( Messages.getMessage( e ), e, this.getLocation() );
         }
         catch ( final JAXBException e )
         {
             String message = Messages.getMessage( e );
             if ( message == null )
             {
                 message = Messages.getMessage( e.getLinkedException() );
             }
 
             throw new BuildException( message, e, this.getLocation() );
         }
         catch ( final TransformerConfigurationException e )
         {
             throw new BuildException( Messages.getMessage( e ), e, this.getLocation() );
         }
         catch ( final TransformerException e )
         {
             throw new BuildException( Messages.getMessage( e ), e, this.getLocation() );
         }
         catch ( final ModelException e )
         {
             throw new BuildException( Messages.getMessage( e ), e, this.getLocation() );
         }
         finally
         {
             try
             {
                 if ( classLoader != null )
                 {
                     classLoader.close();
                 }
             }
             catch ( final IOException e )
             {
                 this.logMessage( Level.SEVERE, Messages.getMessage( e ), e );
             }
         }
     }
 
     /**
      * Tests inclusion of a given modlet based on property {@code modletIncludes}.
      *
      * @param modlet The modlet to test.
      *
      * @return {@code true}, if {@code modlet} is included based on property {@code modletIncludes}.
      *
      * @throws NullPointerException if {@code modlet} is {@code null}.
      *
      * @see #getModletIncludes()
      */
     public boolean isModletIncluded( final Modlet modlet )
     {
         if ( modlet == null )
         {
             throw new NullPointerException( "modlet" );
         }
 
         for ( final NameType include : this.getModletIncludes() )
         {
             if ( include.getName().equals( modlet.getName() ) )
             {
                 return true;
             }
         }
 
         return this.getModletIncludes().isEmpty() ? true : false;
     }
 
     /**
      * Tests exclusion of a given modlet based on property {@code modletExcludes}.
      *
      * @param modlet The modlet to test.
      *
      * @return {@code true}, if {@code modlet} is excluded based on property {@code modletExcludes}.
      *
      * @throws NullPointerException if {@code modlet} is {@code null}.
      *
      * @see #getModletExcludes()
      */
     public boolean isModletExcluded( final Modlet modlet )
     {
         if ( modlet == null )
         {
             throw new NullPointerException( "modlet" );
         }
 
         for ( final NameType exclude : this.getModletExcludes() )
         {
             if ( exclude.getName().equals( modlet.getName() ) )
             {
                 return true;
             }
         }
 
         return false;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public MergeModletsTask clone()
     {
         final MergeModletsTask clone = (MergeModletsTask) super.clone();
         clone.modletFile = this.modletFile != null ? new File( this.modletFile.getAbsolutePath() ) : null;
 
         if ( this.modletResources != null )
         {
             clone.modletResources = new HashSet<ModletResourceType>( this.modletResources.size() );
             for ( final ModletResourceType e : this.modletResources )
             {
                 clone.modletResources.add( e.clone() );
             }
         }
 
         if ( this.modletExcludes != null )
         {
             clone.modletExcludes = new HashSet<NameType>( this.modletExcludes.size() );
             for ( final NameType e : this.modletExcludes )
             {
                 clone.modletExcludes.add( e.clone() );
             }
         }
 
         if ( this.modletIncludes != null )
         {
             clone.modletIncludes = new HashSet<NameType>( this.modletIncludes.size() );
             for ( final NameType e : this.modletIncludes )
             {
                 clone.modletIncludes.add( e.clone() );
             }
         }
 
         if ( this.modletObjectStylesheetResources != null )
         {
             clone.modletObjectStylesheetResources =
                 new ArrayList<TransformerResourceType>( this.modletObjectStylesheetResources.size() );
 
             for ( final TransformerResourceType e : this.modletObjectStylesheetResources )
             {
                 clone.modletObjectStylesheetResources.add( e.clone() );
             }
         }
 
         return clone;
     }
 
 }