//
   //  ========================================================================
   //  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.osgi.boot;
  
  import java.util.Dictionary;
  import java.util.Hashtable;
  
  import org.eclipse.jetty.osgi.boot.internal.serverfactory.DefaultJettyAtJettyHomeHelper;
  import org.eclipse.jetty.osgi.boot.internal.serverfactory.JettyServerServiceTracker;
  import org.eclipse.jetty.osgi.boot.internal.webapp.IWebBundleDeployerHelper;
  import org.eclipse.jetty.osgi.boot.internal.webapp.JettyContextHandlerServiceTracker;
  import org.eclipse.jetty.osgi.boot.internal.webapp.WebBundleTrackerCustomizer;
  import org.eclipse.jetty.osgi.boot.utils.internal.PackageAdminServiceTracker;
  import org.eclipse.jetty.server.Server;
  import org.eclipse.jetty.server.handler.ContextHandler;
  import org.eclipse.jetty.webapp.WebAppContext;
  import org.osgi.framework.Bundle;
  import org.osgi.framework.BundleActivator;
  import org.osgi.framework.BundleContext;
  import org.osgi.framework.BundleException;
  import org.osgi.framework.FrameworkUtil;
  import org.osgi.framework.ServiceRegistration;
  import org.osgi.util.tracker.BundleTracker;
  
  /**
   * Bootstrap jetty and publish a default Server instance as an OSGi service.
   * 
   * Listen for other Server instances to be published as services and support them as deployment targets.
   * 
   * Listen for Bundles to be activated, and deploy those that represent webapps to one of the known Server instances.
   * 
   * <ol>
   * <li>basic servlet [ok]</li>
   * <li>basic jetty.xml [ok]</li>
   * <li>basic jetty.xml and jetty-plus.xml [ok]</li>
   * <li>basic jsp [ok]</li>
   * <li>jsp with tag-libs [ok]</li>
   * <li>test-jndi with atomikos and derby inside ${jetty.home}/lib/ext [ok]</li>
   * </ul>
   */
  public class JettyBootstrapActivator implements BundleActivator
  {
  
      private static JettyBootstrapActivator INSTANCE = null;
  
      public static JettyBootstrapActivator getInstance()
      {
          return INSTANCE;
      }
  
      private ServiceRegistration _registeredServer;
  
      private JettyContextHandlerServiceTracker _jettyContextHandlerTracker;
  
      private PackageAdminServiceTracker _packageAdminServiceTracker;
  
      private BundleTracker _webBundleTracker;
  
      private BundleContext _bundleContext;
  
      private JettyServerServiceTracker _jettyServerServiceTracker;
  
      /**
       * Setup a new jetty Server, registers it as a service. Setup the Service
       * tracker for the jetty ContextHandlers that are in charge of deploying the
       * webapps. Setup the BundleListener that supports the extender pattern for
       * the jetty ContextHandler.
       * 
       * @param context
       */
      public void start(BundleContext context) throws Exception
      {
          INSTANCE = this;
          _bundleContext = context;
  
          // track other bundles and fragments attached to this bundle that we
          // should activate.
          _packageAdminServiceTracker = new PackageAdminServiceTracker(context);
  
          // track jetty Server instances that we should support as deployment targets
          _jettyServerServiceTracker = new JettyServerServiceTracker();
          context.addServiceListener(_jettyServerServiceTracker, "(objectclass=" + Server.class.getName() + ")");
  
         // track ContextHandler class instances and deploy them to one of the known Servers
         _jettyContextHandlerTracker = new JettyContextHandlerServiceTracker();
         context.addServiceListener(_jettyContextHandlerTracker, "(objectclass=" + ContextHandler.class.getName() + ")");
 
         // Create a default jetty instance right now.
         DefaultJettyAtJettyHomeHelper.startJettyAtJettyHome(context);
 
         // track Bundles and deploy those that represent webapps to one of the known Servers
         _webBundleTracker = new BundleTracker(context, Bundle.ACTIVE | Bundle.STOPPING, new WebBundleTrackerCustomizer());
         _webBundleTracker.open();
     }
 
     /**
      * Stop the activator.
      * 
      * @see
      * org.osgi.framework.BundleActivator#stop(org.osgi.framework.BundleContext)
      */
     public void stop(BundleContext context) throws Exception
     {
         try
         {
 
             if (_webBundleTracker != null)
             {
                 _webBundleTracker.close();
                 _webBundleTracker = null;
             }
             if (_jettyContextHandlerTracker != null)
             {
                 context.removeServiceListener(_jettyContextHandlerTracker);
                 _jettyContextHandlerTracker = null;
             }
             if (_jettyServerServiceTracker != null)
             {
                 _jettyServerServiceTracker.stop();
                 context.removeServiceListener(_jettyServerServiceTracker);
                 _jettyServerServiceTracker = null;
             }
             if (_packageAdminServiceTracker != null)
             {
                 _packageAdminServiceTracker.stop();
                 context.removeServiceListener(_packageAdminServiceTracker);
                 _packageAdminServiceTracker = null;
             }
             if (_registeredServer != null)
             {
                 try
                 {
                     _registeredServer.unregister();
                 }
                 catch (IllegalArgumentException ill)
                 {
                     // already unregistered.
                 }
                 finally
                 {
                     _registeredServer = null;
                 }
             }
         }
         finally
         {
             INSTANCE = null;
         }
     }
 
     /**
      * Helper method that creates a new org.jetty.webapp.WebAppContext and
      * registers it as an OSGi service. The tracker
      * {@link JettyContextHandlerServiceTracker} will do the actual deployment.
      * 
      * @param contributor The bundle
      * @param webappFolderPath The path to the root of the webapp. Must be a
      *            path relative to bundle; either an absolute path.
      * @param contextPath The context path. Must start with "/"
      * @throws Exception
      */
     public static void registerWebapplication(Bundle contributor, String webappFolderPath, String contextPath) throws Exception
     {
         checkBundleActivated();
         WebAppContext contextHandler = new WebAppContext();
         Dictionary<String,String> dic = new Hashtable<String,String>();
         dic.put(OSGiWebappConstants.SERVICE_PROP_WAR, webappFolderPath);
         dic.put(OSGiWebappConstants.SERVICE_PROP_CONTEXT_PATH, contextPath);
         String requireTldBundle = (String) contributor.getHeaders().get(OSGiWebappConstants.REQUIRE_TLD_BUNDLE);
         if (requireTldBundle != null)
         {
             dic.put(OSGiWebappConstants.SERVICE_PROP_REQUIRE_TLD_BUNDLE, requireTldBundle);
         }
         contributor.getBundleContext().registerService(ContextHandler.class.getName(), contextHandler, dic);
     }
 
     /**
      * Helper method that creates a new org.jetty.webapp.WebAppContext and
      * registers it as an OSGi service. The tracker
      * {@link JettyContextHandlerServiceTracker} will do the actual deployment.
      * 
      * @param contributor The bundle
      * @param webappFolderPath The path to the root of the webapp. Must be a
      *            path relative to bundle; either an absolute path.
      * @param contextPath The context path. Must start with "/"
      * @param dic TODO: parameter description
      * @throws Exception
      */
     public static void registerWebapplication(Bundle contributor, String webappFolderPath, String contextPath, Dictionary<String, String> dic) throws Exception
     {
         checkBundleActivated();
         WebAppContext contextHandler = new WebAppContext();
         dic.put(OSGiWebappConstants.SERVICE_PROP_WAR, webappFolderPath);
         dic.put(OSGiWebappConstants.SERVICE_PROP_CONTEXT_PATH, contextPath);
         contributor.getBundleContext().registerService(ContextHandler.class.getName(), contextHandler, dic);
     }
 
     /**
      * Helper method that creates a new skeleton of a ContextHandler and
      * registers it as an OSGi service. The tracker
      * {@link JettyContextHandlerServiceTracker} will do the actual deployment.
      * 
      * @param contributor The bundle that registers a new context
      * @param contextFilePath The path to the file inside the bundle that
      *            defines the context.
      * @throws Exception
      */
     public static void registerContext(Bundle contributor, String contextFilePath) throws Exception
     {
         registerContext(contributor, contextFilePath, new Hashtable<String, String>());
     }
 
     /**
      * Helper method that creates a new skeleton of a ContextHandler and
      * registers it as an OSGi service. The tracker
      * {@link JettyContextHandlerServiceTracker} will do the actual deployment.
      * 
      * @param contributor The bundle that registers a new context
      * @param contextFilePath The path to the file inside the bundle that
      *            defines the context.
      * @param dic TODO: parameter description
      * @throws Exception
      */
     public static void registerContext(Bundle contributor, String contextFilePath, Dictionary<String, String> dic) throws Exception
     {
         checkBundleActivated();
         ContextHandler contextHandler = new ContextHandler();
         dic.put(OSGiWebappConstants.SERVICE_PROP_CONTEXT_FILE_PATH, contextFilePath);
         dic.put(IWebBundleDeployerHelper.INTERNAL_SERVICE_PROP_UNKNOWN_CONTEXT_HANDLER_TYPE, Boolean.TRUE.toString());
         contributor.getBundleContext().registerService(ContextHandler.class.getName(), contextHandler, dic);
     }
 
     public static void unregister(String contextPath)
     {
         // todo
     }
 
     /**
      * Since org.eclipse.jetty.osgi.boot does not have a lazy activation policy
      * when one of the static methods to register a webapp is called we should
      * make sure that the bundle is started.
      */
     private static void checkBundleActivated()
     {
         if (INSTANCE == null)
         {
             Bundle thisBundle = FrameworkUtil.getBundle(JettyBootstrapActivator.class);
             try
             {
                 thisBundle.start();
             }
             catch (BundleException e)
             {
                 // nevermind.
             }
         }
     }
 
     /**
      * @return The bundle context for this bundle.
      */
     public static BundleContext getBundleContext()
     {
         checkBundleActivated();
         return INSTANCE._bundleContext;
     }
 
 }