//
   //  ========================================================================
   //  Copyright (c) 1995-2013 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.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  import java.util.ServiceLoader;
  import java.util.Set;
  
  import javax.servlet.ServletContainerInitializer;
  import javax.servlet.ServletContext;
  import javax.servlet.ServletException;
  import javax.servlet.annotation.HandlesTypes;
  
  
  import org.eclipse.jetty.annotations.AnnotationParser.DiscoverableAnnotationHandler;
  import org.eclipse.jetty.plus.annotation.ContainerInitializer;
  import org.eclipse.jetty.util.MultiMap;
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  import org.eclipse.jetty.util.resource.Resource;
  import org.eclipse.jetty.webapp.Configuration;
  import org.eclipse.jetty.webapp.AbstractConfiguration;
  import org.eclipse.jetty.webapp.Descriptor;
  import org.eclipse.jetty.webapp.DiscoveredAnnotation;
  import org.eclipse.jetty.webapp.FragmentDescriptor;
  import org.eclipse.jetty.webapp.MetaDataComplete;
  import org.eclipse.jetty.webapp.WebAppContext;
  import org.eclipse.jetty.webapp.WebDescriptor;
  
  /**
   * Configuration for Annotations
   *
   *
   */
  public class AnnotationConfiguration extends AbstractConfiguration
  {
      private static final Logger LOG = Log.getLogger(AnnotationConfiguration.class);
      public static final String CLASS_INHERITANCE_MAP  = "org.eclipse.jetty.classInheritanceMap";    
      public static final String CONTAINER_INITIALIZERS = "org.eclipse.jetty.containerInitializers";
    
      
      protected List<DiscoverableAnnotationHandler> _discoverableAnnotationHandlers = new ArrayList<DiscoverableAnnotationHandler>();
      protected ClassInheritanceHandler _classInheritanceHandler;
      protected List<ContainerInitializerAnnotationHandler> _containerInitializerAnnotationHandlers = new ArrayList<ContainerInitializerAnnotationHandler>();
      
      
      public void preConfigure(final WebAppContext context) throws Exception
      {
      }
     
      
      
      /** 
       * @see org.eclipse.jetty.webapp.AbstractConfiguration#configure(org.eclipse.jetty.webapp.WebAppContext)
       */
      @Override
      public void configure(WebAppContext context) throws Exception
      {
         boolean metadataComplete = context.getMetaData().isMetaDataComplete();
         context.addDecorator(new AnnotationDecorator(context));   
        
         
         //Even if metadata is complete, we still need to scan for ServletContainerInitializers - if there are any
         AnnotationParser parser = null;
         if (!metadataComplete)
         {
             //If metadata isn't complete, if this is a servlet 3 webapp or isConfigDiscovered is true, we need to search for annotations
             if (context.getServletContext().getEffectiveMajorVersion() >= 3 || context.isConfigurationDiscovered())
             {
                 _discoverableAnnotationHandlers.add(new WebServletAnnotationHandler(context));
                 _discoverableAnnotationHandlers.add(new WebFilterAnnotationHandler(context));
                 _discoverableAnnotationHandlers.add(new WebListenerAnnotationHandler(context));
             }
         }
         else
             if (LOG.isDebugEnabled()) LOG.debug("Metadata-complete==true,  not processing discoverable servlet annotations for context "+context);
         
         
         
         //Regardless of metadata, if there are any ServletContainerInitializers with @HandlesTypes, then we need to scan all the
        //classes so we can call their onStartup() methods correctly
        createServletContainerInitializerAnnotationHandlers(context, getNonExcludedInitializers(context));
        
        if (!_discoverableAnnotationHandlers.isEmpty() || _classInheritanceHandler != null || !_containerInitializerAnnotationHandlers.isEmpty())
        {           
            parser = createAnnotationParser();
            if (LOG.isDebugEnabled()) LOG.debug("Scanning all classses for annotations: webxmlVersion="+context.getServletContext().getEffectiveMajorVersion()+" configurationDiscovered="+context.isConfigurationDiscovered());
            parseContainerPath(context, parser);
            //email from Rajiv Mordani jsrs 315 7 April 2010
            //    If there is a <others/> then the ordering should be 
            //          WEB-INF/classes the order of the declared elements + others.
            //    In case there is no others then it is 
            //          WEB-INF/classes + order of the elements.
            parseWebInfClasses(context, parser);
            parseWebInfLib (context, parser);
            
            for (DiscoverableAnnotationHandler h:_discoverableAnnotationHandlers)
                context.getMetaData().addDiscoveredAnnotations(((AbstractDiscoverableAnnotationHandler)h).getAnnotationList());      
        }
     }
     
     
     
     /** 
      * @see org.eclipse.jetty.webapp.AbstractConfiguration#postConfigure(org.eclipse.jetty.webapp.WebAppContext)
      */
     @Override
     public void postConfigure(WebAppContext context) throws Exception
     {
         MultiMap map = (MultiMap)context.getAttribute(CLASS_INHERITANCE_MAP);
         if (map != null)
             map.clear();
         
         context.removeAttribute(CLASS_INHERITANCE_MAP);
         
         List<ContainerInitializer> initializers = (List<ContainerInitializer>)context.getAttribute(CONTAINER_INITIALIZERS);
         if (initializers != null)
             initializers.clear();
         if (_discoverableAnnotationHandlers != null)
             _discoverableAnnotationHandlers.clear();
       
         _classInheritanceHandler = null;
         if (_containerInitializerAnnotationHandlers != null)
             _containerInitializerAnnotationHandlers.clear();
   
         super.postConfigure(context);
     }
 
     /**
      * @return a new AnnotationParser. This method can be overridden to use a different impleemntation of
      * the AnnotationParser. Note that this is considered internal API.
      */
     protected AnnotationParser createAnnotationParser()
     {
         return new AnnotationParser();
     }
     
     /** 
      * @see org.eclipse.jetty.webapp.AbstractConfiguration#cloneConfigure(org.eclipse.jetty.webapp.WebAppContext, org.eclipse.jetty.webapp.WebAppContext)
      */
     @Override
     public void cloneConfigure(WebAppContext template, WebAppContext context) throws Exception
     {
         context.addDecorator(new AnnotationDecorator(context));   
     }
     
     
     
     /**
      * @param context
      * @param scis
      * @throws Exception
      */
     public void createServletContainerInitializerAnnotationHandlers (WebAppContext context, List<ServletContainerInitializer> scis)
     throws Exception
     {
         
         if (scis == null || scis.isEmpty())
             return; // nothing to do
         
 
         List<ContainerInitializer> initializers = new ArrayList<ContainerInitializer>();
         context.setAttribute(CONTAINER_INITIALIZERS, initializers);
 
         for (ServletContainerInitializer service : scis)
         {
             HandlesTypes annotation = service.getClass().getAnnotation(HandlesTypes.class);
             ContainerInitializer initializer = new ContainerInitializer();
             initializer.setTarget(service);
             initializers.add(initializer);
             if (annotation != null)
             {
                 //There is a HandlesTypes annotation on the on the ServletContainerInitializer
                 Class[] classes = annotation.value();
                 if (classes != null)
                 {
                     initializer.setInterestedTypes(classes);
 
                     //If we haven't already done so, we need to register a handler that will
                     //process the whole class hierarchy to satisfy the ServletContainerInitializer
                     if (context.getAttribute(CLASS_INHERITANCE_MAP) == null)
                     {
                         MultiMap map = new MultiMap();
                         context.setAttribute(CLASS_INHERITANCE_MAP, map);
                         _classInheritanceHandler = new ClassInheritanceHandler(map);
                     }
                                      
                     for (Class c: classes)
                     {
                         //The value of one of the HandlesTypes classes is actually an Annotation itself so
                         //register a handler for it
                         if (c.isAnnotation())
                         {
                             if (LOG.isDebugEnabled()) LOG.debug("Registering annotation handler for "+c.getName());
                            
                            _containerInitializerAnnotationHandlers.add(new ContainerInitializerAnnotationHandler(initializer, c));
                         }
                     }
                 }
                 else
                     if (LOG.isDebugEnabled()) LOG.debug("No classes in HandlesTypes on initializer "+service.getClass());
             }
             else
                 if (LOG.isDebugEnabled()) LOG.debug("No annotation on initializer "+service.getClass());
         }
         
 
         //add a listener which will call the servletcontainerinitializers when appropriate
         ServletContainerInitializerListener listener = new ServletContainerInitializerListener();
         listener.setWebAppContext(context);
         context.addEventListener(listener);
     }
 
     
     
     /**
      * Check to see if the ServletContainerIntializer loaded via the ServiceLoader came
      * from a jar that is excluded by the fragment ordering. See ServletSpec 3.0 p.85.
      * @param orderedJars
      * @param service
      * @return
      */
     public boolean isFromExcludedJar (WebAppContext context, ServletContainerInitializer service)
     throws Exception
     {
         List<Resource> orderedJars = context.getMetaData().getOrderedWebInfJars();
 
         //If no ordering, nothing is excluded
         if (context.getMetaData().getOrdering() == null)
             return false;
 
         //there is an ordering, but there are no jars resulting from the ordering, everything excluded
         if (orderedJars.isEmpty())
             return true; 
 
         String loadingJarName = Thread.currentThread().getContextClassLoader().getResource(service.getClass().getName().replace('.','/')+".class").toString();
 
         int i = loadingJarName.indexOf(".jar");  
         if (i < 0)
             return false; //not from a jar therefore not from WEB-INF so not excludable
 
         loadingJarName = loadingJarName.substring(0,i+4);
         loadingJarName = (loadingJarName.startsWith("jar:")?loadingJarName.substring(4):loadingJarName);
         URI loadingJarURI = Resource.newResource(loadingJarName).getURI();
         boolean found = false;
         Iterator<Resource> itor = orderedJars.iterator();
         while (!found && itor.hasNext())
         {
             Resource r = itor.next();         
             found = r.getURI().equals(loadingJarURI);
         }
 
         return !found;
     }
    
     
     
     /**
      * @param context
      * @return
      * @throws Exception
      */
     public List<ServletContainerInitializer> getNonExcludedInitializers (WebAppContext context)
     throws Exception
     {
         List<ServletContainerInitializer> nonExcludedInitializers = new ArrayList<ServletContainerInitializer>();
         
         //We use the ServiceLoader mechanism to find the ServletContainerInitializer classes to inspect
         ServiceLoader<ServletContainerInitializer> loadedInitializers = ServiceLoader.load(ServletContainerInitializer.class, context.getClassLoader());
        
         if (loadedInitializers != null)
         {  
             for (ServletContainerInitializer service : loadedInitializers)
             {
                 if (!isFromExcludedJar(context, service))
                     nonExcludedInitializers.add(service);
             }
         }
         return nonExcludedInitializers;
     }
     
     
     
     
     /**
      * Scan jars on container path.
      * 
      * @param context
      * @param parser
      * @throws Exception
      */
     public void parseContainerPath (final WebAppContext context, final AnnotationParser parser)
     throws Exception
     {
         //if no pattern for the container path is defined, then by default scan NOTHING
         LOG.debug("Scanning container jars");
         
         //always parse for discoverable annotations as well as class hierarchy and servletcontainerinitializer related annotations
         parser.clearHandlers();
         for (DiscoverableAnnotationHandler h:_discoverableAnnotationHandlers)
         {
             if (h instanceof AbstractDiscoverableAnnotationHandler)
                 ((AbstractDiscoverableAnnotationHandler)h).setResource(null); //
         }
         parser.registerHandlers(_discoverableAnnotationHandlers);
         parser.registerHandler(_classInheritanceHandler);
         parser.registerHandlers(_containerInitializerAnnotationHandlers);
         
         //Convert from Resource to URI
         ArrayList<URI> containerUris = new ArrayList<URI>();
         for (Resource r : context.getMetaData().getOrderedContainerJars())
         {
             URI uri = r.getURI();
                 containerUris.add(uri);          
         }
         
         parser.parse (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;
                     }
                 });   
         
          
     }
     
     
     /**
      * Scan jars in WEB-INF/lib
      * 
      * @param context
      * @param parser
      * @throws Exception
      */
     public void parseWebInfLib (final WebAppContext context, final AnnotationParser parser)
     throws Exception
     {  
         List<FragmentDescriptor> frags = context.getMetaData().getFragments();
         
         //email from Rajiv Mordani jsrs 315 7 April 2010
         //jars that do not have a web-fragment.xml are still considered fragments
         //they have to participate in the ordering
         ArrayList<URI> webInfUris = new ArrayList<URI>();
         
         List<Resource> jars = context.getMetaData().getOrderedWebInfJars();
         
         //No ordering just use the jars in any order
         if (jars == null || jars.isEmpty())
             jars = context.getMetaData().getWebInfJars();
    
         for (Resource r : jars)
         {          
             //for each jar, we decide which set of annotations we need to parse for
             parser.clearHandlers();
             URI uri  = r.getURI();
             FragmentDescriptor f = getFragmentFromJar(r, frags);
            
             //if its from a fragment jar that is metadata complete, we should skip scanning for @webservlet etc
             // but yet we still need to do the scanning for the classes on behalf of  the servletcontainerinitializers
             //if a jar has no web-fragment.xml we scan it (because it is not excluded by the ordering)
             //or if it has a fragment we scan it if it is not metadata complete
             if (f == null || !isMetaDataComplete(f) || _classInheritanceHandler != null ||  !_containerInitializerAnnotationHandlers.isEmpty())
             {
                 //register the classinheritance handler if there is one
                 parser.registerHandler(_classInheritanceHandler);
                 
                 //register the handlers for the @HandlesTypes values that are themselves annotations if there are any
                 parser.registerHandlers(_containerInitializerAnnotationHandlers);
                 
                 //only register the discoverable annotation handlers if this fragment is not metadata complete, or has no fragment descriptor
                 if (f == null || !isMetaDataComplete(f))
                 {
                     for (DiscoverableAnnotationHandler h:_discoverableAnnotationHandlers)
                     {
                         if (h instanceof AbstractDiscoverableAnnotationHandler)
                             ((AbstractDiscoverableAnnotationHandler)h).setResource(r);
                     }
                     parser.registerHandlers(_discoverableAnnotationHandlers);
                 }
 
                 parser.parse(uri, 
                              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;
                                  }
                              });   
             }
         }
     }
      
     /**
      * Scan classes in WEB-INF/classes
      * 
      * @param context
      * @param parser
      * @throws Exception
      */
     public void parseWebInfClasses (final WebAppContext context, final AnnotationParser parser)
     throws Exception
     {
         LOG.debug("Scanning classes in WEB-INF/classes");
         if (context.getWebInf() != null)
         {
             Resource classesDir = context.getWebInf().addPath("classes/");
             if (classesDir.exists())
             {
                 parser.clearHandlers();
                 for (DiscoverableAnnotationHandler h:_discoverableAnnotationHandlers)
                 {
                     if (h instanceof AbstractDiscoverableAnnotationHandler)
                         ((AbstractDiscoverableAnnotationHandler)h).setResource(null); //
                 }
                 parser.registerHandlers(_discoverableAnnotationHandlers);
                 parser.registerHandler(_classInheritanceHandler);
                 parser.registerHandlers(_containerInitializerAnnotationHandlers);
                 
                 parser.parse(classesDir, 
                              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;
                     }
                 });
             }
         }
     }
     
  
     
     /**
      * Get the web-fragment.xml from a jar
      * 
      * @param jar
      * @param frags
      * @return
      * @throws Exception
      */
     public FragmentDescriptor getFragmentFromJar (Resource jar,  List<FragmentDescriptor> frags)
     throws Exception
     {
         //check if the jar has a web-fragment.xml
         FragmentDescriptor d = null;
         for (FragmentDescriptor frag: frags)
         {
             Resource fragResource = frag.getResource(); //eg jar:file:///a/b/c/foo.jar!/META-INF/web-fragment.xml
             if (Resource.isContainedIn(fragResource,jar))
             {
                 d = frag;
                 break;
             }
         }
         return d;
     }
     
     public boolean isMetaDataComplete (WebDescriptor d)
     {
         return (d!=null && d.getMetaDataComplete() == MetaDataComplete.True);
     }
 }