/*
    *   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: JomcModelTask.java 5263 2016-05-01 23:44:12Z schulte $
   *
   */
  package org.jomc.ant;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.HttpURLConnection;
  import java.net.SocketTimeoutException;
  import java.net.URISyntaxException;
  import java.net.URL;
  import java.net.URLConnection;
  import java.util.HashSet;
  import java.util.Set;
  import java.util.logging.Level;
  import javax.xml.bind.JAXBElement;
  import javax.xml.bind.JAXBException;
  import javax.xml.bind.Unmarshaller;
  import javax.xml.transform.Source;
  import javax.xml.transform.stream.StreamSource;
  import org.apache.tools.ant.BuildException;
  import org.apache.tools.ant.Project;
  import org.jomc.ant.types.KeyValueType;
  import org.jomc.ant.types.ModuleResourceType;
  import org.jomc.ant.types.ResourceType;
  import org.jomc.model.Module;
  import org.jomc.model.Modules;
  import org.jomc.model.modlet.DefaultModelProcessor;
  import org.jomc.model.modlet.DefaultModelProvider;
  import org.jomc.model.modlet.DefaultModelValidator;
  import org.jomc.model.modlet.ModelHelper;
  import org.jomc.modlet.Model;
  import org.jomc.modlet.ModelContext;
  import org.jomc.modlet.ModelException;
  import org.jomc.tools.modlet.ToolsModelProcessor;
  import org.jomc.tools.modlet.ToolsModelProvider;
  
  /**
   * Base class for executing model based tasks.
   *
   * @author <a href="mailto:cs@schulte.it">Christian Schulte</a>
   * @version $JOMC: JomcModelTask.java 5263 2016-05-01 23:44:12Z schulte $
   */
  public class JomcModelTask extends JomcTask
  {
  
      /**
       * Controls model object class path resolution.
       */
      private boolean modelObjectClasspathResolutionEnabled = true;
  
      /**
       * The location to search for modules.
       */
      private String moduleLocation;
  
      /**
       * The location to search for transformers.
       */
      private String transformerLocation;
  
      /**
       * Module resources.
       */
      private Set<ModuleResourceType> moduleResources;
  
      /**
       * The flag indicating JAXP schema validation of model resources is enabled.
       */
      private boolean modelResourceValidationEnabled = true;
  
      /**
      * The flag indicating Java validation is enabled.
      */
     private boolean javaValidationEnabled = true;
 
     /**
      * Creates a new {@code JomcModelTask} instance.
      */
     public JomcModelTask()
     {
         super();
     }
 
     /**
      * Gets the location searched for modules.
      *
      * @return The location searched for modules or {@code null}.
      *
      * @see #setModuleLocation(java.lang.String)
      */
     public final String getModuleLocation()
     {
         return this.moduleLocation;
     }
 
     /**
      * Sets the location to search for modules.
      *
      * @param value The new location to search for modules or {@code null}.
      *
      * @see #getModuleLocation()
      */
     public final void setModuleLocation( final String value )
     {
         this.moduleLocation = value;
     }
 
     /**
      * Gets the location searched for transformers.
      *
      * @return The location searched for transformers or {@code null}.
      *
      * @see #setTransformerLocation(java.lang.String)
      */
     public final String getTransformerLocation()
     {
         return this.transformerLocation;
     }
 
     /**
      * Sets the location to search for transformers.
      *
      * @param value The new location to search for transformers or {@code null}.
      *
      * @see #getTransformerLocation()
      */
     public final void setTransformerLocation( final String value )
     {
         this.transformerLocation = value;
     }
 
     /**
      * Gets a flag indicating model object class path resolution is enabled.
      *
      * @return {@code true}, if model object class path resolution is enabled; {@code false}, else.
      *
      * @see #setModelObjectClasspathResolutionEnabled(boolean)
      */
     public final boolean isModelObjectClasspathResolutionEnabled()
     {
         return this.modelObjectClasspathResolutionEnabled;
     }
 
     /**
      * Sets the flag indicating model object class path resolution is enabled.
      *
      * @param value {@code true}, to enable model object class path resolution; {@code false}, to disable model object
      * class path resolution.
      *
      * @see #isModelObjectClasspathResolutionEnabled()
      */
     public final void setModelObjectClasspathResolutionEnabled( final boolean value )
     {
         this.modelObjectClasspathResolutionEnabled = value;
     }
 
     /**
      * Gets a set of module resources.
      * <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
      * module resources property.
      * </p>
      *
      * @return A set of module resources.
      *
      * @see #createModuleResource()
      */
     public Set<ModuleResourceType> getModuleResources()
     {
         if ( this.moduleResources == null )
         {
             this.moduleResources = new HashSet<ModuleResourceType>();
         }
 
         return this.moduleResources;
     }
 
     /**
      * Creates a new {@code moduleResource} element instance.
      *
      * @return A new {@code moduleResource} element instance.
      *
      * @see #getModuleResources()
      */
     public ModuleResourceType createModuleResource()
     {
         final ModuleResourceType moduleResource = new ModuleResourceType();
         this.getModuleResources().add( moduleResource );
         return moduleResource;
     }
 
     /**
      * Gets a flag indicating JAXP schema validation of model resources is enabled.
      *
      * @return {@code true}, if JAXP schema validation of model resources is enabled; {@code false}, else.
      *
      * @see #setModelResourceValidationEnabled(boolean)
      */
     public final boolean isModelResourceValidationEnabled()
     {
         return this.modelResourceValidationEnabled;
     }
 
     /**
      * Sets the flag indicating JAXP schema validation of model resources is enabled.
      *
      * @param value {@code true}, to enable JAXP schema validation of model resources; {@code false}, to disable JAXP
      * schema validation of model resources.
      *
      * @see #isModelResourceValidationEnabled()
      */
     public final void setModelResourceValidationEnabled( final boolean value )
     {
         this.modelResourceValidationEnabled = value;
     }
 
     /**
      * Gets a flag indicating Java validation is enabled.
      *
      * @return {@code true}, if Java validation is enabled; {@code false}, else.
      *
      * @see #setJavaValidationEnabled(boolean)
      *
      * @since 1.4
      */
     public final boolean isJavaValidationEnabled()
     {
         return this.javaValidationEnabled;
     }
 
     /**
      * Sets the flag indicating Java validation is enabled.
      *
      * @param value {@code true}, to enable Java validation; {@code false}, to disable Java validation.
      *
      * @see #isJavaValidationEnabled()
      *
      * @since 1.4
      */
     public final void setJavaValidationEnabled( final boolean value )
     {
         this.javaValidationEnabled = value;
     }
 
     /**
      * Gets a {@code Model} from a given {@code ModelContext}.
      *
      * @param context The context to get a {@code Model} from.
      *
      * @return The {@code Model} from {@code context}.
      *
      * @throws NullPointerException if {@code contexŧ} is {@code null}.
      * @throws BuildException if no model is found.
      * @throws ModelException if getting the model fails.
      *
      * @see #getModel()
      * @see #isModelObjectClasspathResolutionEnabled()
      * @see #isModelProcessingEnabled()
      */
     @Override
     public Model getModel( final ModelContext context ) throws BuildException, ModelException
     {
         if ( context == null )
         {
             throw new NullPointerException( "context" );
         }
 
         Model model = new Model();
         model.setIdentifier( this.getModel() );
         Modules modules = new Modules();
         ModelHelper.setModules( model, modules );
         Unmarshaller unmarshaller = null;
 
         for ( final ResourceType resource : this.getModuleResources() )
         {
             final URL[] urls = this.getResources( context, resource.getLocation() );
 
             if ( urls.length == 0 )
             {
                 if ( resource.isOptional() )
                 {
                     this.logMessage( Level.WARNING, Messages.getMessage( "moduleResourceNotFound",
                                                                          resource.getLocation() ) );
 
                 }
                 else
                 {
                     throw new BuildException( Messages.getMessage( "moduleResourceNotFound", resource.getLocation() ),
                                               this.getLocation() );
 
                 }
             }
 
             for ( int i = urls.length - 1; i >= 0; i-- )
             {
                 URLConnection con = null;
                 InputStream in = 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() );
 
                     if ( unmarshaller == null )
                     {
                         unmarshaller = context.createUnmarshaller( this.getModel() );
                         if ( this.isModelResourceValidationEnabled() )
                         {
                             unmarshaller.setSchema( context.createSchema( this.getModel() ) );
                         }
                     }
 
                     Object o = unmarshaller.unmarshal( source );
                     if ( o instanceof JAXBElement<?> )
                     {
                         o = ( (JAXBElement<?>) o ).getValue();
                     }
 
                     if ( o instanceof Module )
                     {
                         modules.getModule().add( (Module) o );
                     }
                     else
                     {
                         this.log( Messages.getMessage( "unsupportedModuleResource", urls[i].toExternalForm() ),
                                   Project.MSG_WARN );
 
                     }
 
                     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() );
                     }
                 }
                 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() );
                 }
                 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();
                         }
                     }
                 }
             }
         }
 
         model = context.findModel( model );
         modules = ModelHelper.getModules( model );
 
         if ( modules != null && this.isModelObjectClasspathResolutionEnabled() )
         {
             final Module classpathModule =
                 modules.getClasspathModule( Modules.getDefaultClasspathModuleName(), context.getClassLoader() );
 
             if ( classpathModule != null && modules.getModule( Modules.getDefaultClasspathModuleName() ) == null )
             {
                 modules.getModule().add( classpathModule );
             }
         }
 
         if ( this.isModelProcessingEnabled() )
         {
             model = context.processModel( model );
         }
 
         return model;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void preExecuteTask() throws BuildException
     {
         super.preExecuteTask();
         this.assertLocationsNotNull( this.getModuleResources() );
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public ModelContext newModelContext( final ClassLoader classLoader ) throws ModelException
     {
         final ModelContext modelContext = super.newModelContext( classLoader );
 
         if ( this.getTransformerLocation() != null )
         {
             modelContext.setAttribute( DefaultModelProcessor.TRANSFORMER_LOCATION_ATTRIBUTE_NAME,
                                        this.getTransformerLocation() );
 
         }
 
         if ( this.getModuleLocation() != null )
         {
             modelContext.setAttribute( DefaultModelProvider.MODULE_LOCATION_ATTRIBUTE_NAME, this.getModuleLocation() );
         }
 
         modelContext.setAttribute( ToolsModelProvider.MODEL_OBJECT_CLASSPATH_RESOLUTION_ENABLED_ATTRIBUTE_NAME,
                                    this.isModelObjectClasspathResolutionEnabled() );
 
         modelContext.setAttribute( ToolsModelProcessor.MODEL_OBJECT_CLASSPATH_RESOLUTION_ENABLED_ATTRIBUTE_NAME,
                                    this.isModelObjectClasspathResolutionEnabled() );
 
         modelContext.setAttribute( DefaultModelProvider.VALIDATING_ATTRIBUTE_NAME,
                                    this.isModelResourceValidationEnabled() );
 
         modelContext.setAttribute( DefaultModelValidator.VALIDATE_JAVA_ATTRIBUTE_NAME, this.isJavaValidationEnabled() );
 
         for ( int i = 0, s0 = this.getModelContextAttributes().size(); i < s0; i++ )
         {
             final KeyValueType kv = this.getModelContextAttributes().get( i );
             final Object object = kv.getObject( this.getLocation() );
 
             if ( object != null )
             {
                 modelContext.setAttribute( kv.getKey(), object );
             }
             else
             {
                 modelContext.clearAttribute( kv.getKey() );
             }
         }
 
         return modelContext;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public JomcModelTask clone()
     {
         final JomcModelTask clone = (JomcModelTask) super.clone();
 
         if ( this.moduleResources != null )
         {
             clone.moduleResources = new HashSet<ModuleResourceType>( this.moduleResources.size() );
             for ( final ModuleResourceType e : this.moduleResources )
             {
                 clone.moduleResources.add( e.clone() );
             }
         }
 
         return clone;
     }
 
 }