// ========================================================================
   // Copyright (c) 2006-2009 Mort Bay Consulting Pty. Ltd.
   // ------------------------------------------------------------------------
   // All rights reserved. This program and the accompanying materials
   // are made available under the terms of the Eclipse Public License v1.0
   // and Apache License v2.0 which accompanies this distribution.
   // The Eclipse Public License is available at 
   // http://www.eclipse.org/legal/epl-v10.html
   // The Apache License v2.0 is available at
  // http://www.opensource.org/licenses/apache2.0.php
  // You may elect to redistribute this code under either of these licenses. 
  // ========================================================================
  
  package org.eclipse.jetty.annotations;
  
  import java.net.URI;
  import java.net.URL;
  import java.net.URLClassLoader;
  import java.util.ArrayList;
  import java.util.EventListener;
  import java.util.List;
  
  import org.eclipse.jetty.plus.servlet.ServletHandler;
  import org.eclipse.jetty.servlet.FilterHolder;
  import org.eclipse.jetty.servlet.FilterMapping;
  import org.eclipse.jetty.servlet.ServletHolder;
  import org.eclipse.jetty.servlet.ServletMapping;
  import org.eclipse.jetty.util.LazyList;
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.resource.Resource;
  import org.eclipse.jetty.webapp.WebAppContext;
  import org.eclipse.jetty.webapp.WebInfConfiguration;
  
  /**
   * Configuration
   *
   *
   */
  public class AnnotationConfiguration extends org.eclipse.jetty.plus.webapp.Configuration
  {
      public static final String JAR_RESOURCES = WebInfConfiguration.JAR_RESOURCES;
                                                        
      
      
      /** 
       * @see org.eclipse.jetty.plus.webapp.AbstractConfiguration#parseAnnotations()
       */
      public void parseAnnotations(final WebAppContext context) throws Exception
      {
          /*
           * TODO Need to also take account of hidden classes on system classpath that should never
           * contribute annotations to a webapp (system and server classes):
           * 
           * --- when scanning system classpath:
           *   + system classes : should always be scanned (subject to pattern)
           *   + server classes : always ignored
           *   
           * --- when scanning webapp classpath:
           *   + system classes : always ignored
           *   + server classes : always scanned
           * 
           * 
           * If same class is found in both container and in context then need to use
           * webappcontext parentloaderpriority to work out which one contributes the
           * annotation.
           */
          AnnotationFinder finder = new AnnotationFinder();
  
          //TODO change for servlet spec 3
          parseContainerPath (context, finder);
          parseWebInfLib (context, finder);
          parseWebInfClasses (context, finder);
  
          AnnotationProcessor processor = new AnnotationProcessor(context, finder);
          processor.process();
          
          List servlets = processor.getServlets();
          List filters = processor.getFilters();
          List servletMappings = processor.getServletMappings();
          List filterMappings = processor.getFilterMappings();
          List listeners = processor.getListeners();
          
          ServletHandler servletHandler = (ServletHandler)context.getServletHandler();
          servletHandler.setFilters((FilterHolder[])LazyList.toArray(filters,FilterHolder.class));
          servletHandler.setFilterMappings((FilterMapping[])LazyList.toArray(filterMappings,FilterMapping.class));
          servletHandler.setServlets((ServletHolder[])LazyList.toArray(servlets,ServletHolder.class));
          servletHandler.setServletMappings((ServletMapping[])LazyList.toArray(servletMappings,ServletMapping.class));
          context.setEventListeners((EventListener[])LazyList.toArray(listeners,EventListener.class));
      }
      
      public void parseContainerPath (final WebAppContext context, final AnnotationFinder finder)
      throws Exception
      {
          //if no pattern for the container path is defined, then by default scan NOTHING
          Log.debug("Scanning container jars");
          
          //Get the container jar uris
          
          ArrayList<URI> containerCandidateUris = findJars (context.getClassLoader().getParent(), true);
         
         //Pick out the uris from JAR_RESOURCES that match those uris to be scanned
         ArrayList<URI> containerUris = new ArrayList<URI>();
         List<Resource> jarResources = (List<Resource>)context.getAttribute(JAR_RESOURCES);
         for (Resource r : jarResources)
         {
             URI uri = r.getURI();
             if (containerCandidateUris.contains(uri))
             {
                 containerUris.add(uri);
             }
                
         }
         
         finder.find (containerUris.toArray(new URI[containerUris.size()]),
                 new ClassNameResolver ()
                 {
                     public boolean isExcluded (String name)
                     {
                         if (context.isSystemClass(name)) return false;
                         if (context.isServerClass(name)) return true;
                         return false;
                     }
 
                     public boolean shouldOverride (String name)
                     { 
                         //looking at system classpath
                         if (context.isParentLoaderPriority())
                             return true;
                         return false;
                     }
                 });
     }
     
     
     public void parseWebInfLib (final WebAppContext context, final AnnotationFinder finder)
     throws Exception
     {
         Log.debug("Scanning WEB-INF/lib jars");
         //Get the uris of jars on the webapp classloader
         ArrayList<URI> candidateUris = findJars(context.getClassLoader(), false);
         
         //Pick out the uris from JAR_RESOURCES that match those to be scanned
         ArrayList<URI> webInfUris = new ArrayList<URI>();
         List<Resource> jarResources = (List<Resource>)context.getAttribute(JAR_RESOURCES);
         for (Resource r : jarResources)
         {
             URI uri = r.getURI();
             if (candidateUris.contains(uri))
             {
                 webInfUris.add(uri);
             }
         }
         
         //if no pattern for web-inf/lib is defined, then by default scan everything in it
        finder.find(webInfUris.toArray(new URI[webInfUris.size()]), 
                 new ClassNameResolver()
                 {
                     public boolean isExcluded (String name)
                     {    
                         if (context.isSystemClass(name)) return true;
                         if (context.isServerClass(name)) return false;
                         return false;
                     }
 
                     public boolean shouldOverride (String name)
                     {
                         //looking at webapp classpath, found already-parsed class of same name - did it come from system or duplicate in webapp?
                         if (context.isParentLoaderPriority())
                             return false;
                         return true;
                     }
                 });  
                 
     }
      
     public void parseWebInfClasses (final WebAppContext context, final AnnotationFinder finder)
     throws Exception
     {
         Log.debug("Scanning classes in WEB-INF/classes");
         finder.find(context.getWebInf().addPath("classes/"), 
                     new ClassNameResolver()
         {
             public boolean isExcluded (String name)
             {
                 if (context.isSystemClass(name)) return true;
                 if (context.isServerClass(name)) return false;
                 return false;
             }
 
             public boolean shouldOverride (String name)
             {
                 //looking at webapp classpath, found already-parsed class of same name - did it come from system or duplicate in webapp?
                 if (context.isParentLoaderPriority())
                     return false;
                 return true;
             }
         });
     }
 
     
 
     public ArrayList<URI> findJars (ClassLoader loader, boolean visitParent)
     {
         ArrayList<URI> uris = new ArrayList<URI>();
        
         while (loader != null && (loader instanceof URLClassLoader))
         {
             URL[] urls = ((URLClassLoader)loader).getURLs();
             if (urls != null)
             {
                 for (URL u : urls)
                 {
                     try
                     {
                         uris.add(u.toURI());
                     }
                     catch (Exception e)
                     {
                         Log.warn(e);
                     }
                 } 
             }
             if (visitParent)
                 loader = loader.getParent();
             else
                 loader = null;
         }
         return uris;
     }
 }