// ========================================================================
   // Copyright (c) 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.webapp;
  
  
  import java.net.URI;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.jar.JarEntry;
  
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  import org.eclipse.jetty.util.resource.Resource;
  
  /**
   * MetaInfConfiguration
   *
   * Scan META-INF of all jars in WEB-INF/lib to find:
   * <ul>
   * <li>tlds
   * <li>web-fragment.xml
   * <li>resources
   * </ul>
   */
  public class MetaInfConfiguration extends AbstractConfiguration
  {
      private static final Logger LOG = Log.getLogger(MetaInfConfiguration.class);
  
      public static final String METAINF_TLDS = TagLibConfiguration.TLD_RESOURCES;
      public static final String METAINF_FRAGMENTS = FragmentConfiguration.FRAGMENT_RESOURCES;
      public static final String METAINF_RESOURCES = WebInfConfiguration.RESOURCE_URLS;
    
      @Override
      public void preConfigure(final WebAppContext context) throws Exception
      {
         //Merge all container and webinf lib jars to look for META-INF resources
        
          ArrayList<Resource> jars = new ArrayList<Resource>();
          jars.addAll(context.getMetaData().getOrderedContainerJars());
          jars.addAll(context.getMetaData().getWebInfJars());
          
          JarScanner scanner = new JarScanner()
          {
              public void processEntry(URI jarUri, JarEntry entry)
              {
                  try
                  {
                      MetaInfConfiguration.this.processEntry(context,jarUri,entry);
                  }
                  catch (Exception e)
                  {
                      LOG.warn("Problem processing jar entry " + entry, e);
                  }
              }
          };
          
          
          //Scan jars for META-INF information
          if (jars != null)
          {
              URI[] uris = new URI[jars.size()];
              int i=0;
              for (Resource r : jars)
              {
                  uris[i++] = r.getURI();
              }
              scanner.scan(null, uris, true);
          }
      }
  
      @Override
      public void postConfigure(WebAppContext context) throws Exception
      {
          context.setAttribute(METAINF_FRAGMENTS, null); 
          context.setAttribute(METAINF_RESOURCES, null);
          context.setAttribute(METAINF_TLDS, null);
      }
  
      public void addResource (WebAppContext context, String attribute, Resource jar)
      {
          @SuppressWarnings("unchecked")
          List<Resource> list = (List<Resource>)context.getAttribute(attribute);
          if (list==null)
          {
              list=new ArrayList<Resource>();
              context.setAttribute(attribute,list);
          }
          if (!list.contains(jar))
             list.add(jar);
     }
     
     
     protected void processEntry(WebAppContext context, URI jarUri, JarEntry entry)
     {
         String name = entry.getName();
 
         if (!name.startsWith("META-INF/"))
             return;
         
         try
         {
             if (name.equals("META-INF/web-fragment.xml") && context.isConfigurationDiscovered())
             {
                 addResource(context,METAINF_FRAGMENTS,Resource.newResource(jarUri));     
             }
             else if (name.equals("META-INF/resources/") && context.isConfigurationDiscovered())
             {
                 addResource(context,METAINF_RESOURCES,Resource.newResource("jar:"+jarUri+"!/META-INF/resources"));
             }
             else
             {
                 String lcname = name.toLowerCase();
                 if (lcname.endsWith(".tld"))
                 {
                     addResource(context,METAINF_TLDS,Resource.newResource("jar:"+jarUri+"!/"+name));
                 }
             }
         }
         catch(Exception e)
         {
             context.getServletContext().log(jarUri+"!/"+name,e);
         }
     }
 }