//
   //  ========================================================================
   //  Copyright (c) 1995-2014 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 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.BundleWatcher;
  import org.eclipse.jetty.osgi.boot.internal.webapp.ServiceWatcher;
  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.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  import org.osgi.framework.Bundle;
  import org.osgi.framework.BundleActivator;
  import org.osgi.framework.BundleContext;
  import org.osgi.framework.ServiceRegistration;
  import org.osgi.util.tracker.BundleTracker;
  
  /**
   * JettyBootstrapActivator
   * 
   * 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/ContextHandlers to one of the known Server instances.
   * 
   */
  public class JettyBootstrapActivator implements BundleActivator
  {
      private static final Logger LOG = Log.getLogger(JettyBootstrapActivator.class);
      
      private static JettyBootstrapActivator INSTANCE = null;
  
      public static JettyBootstrapActivator getInstance()
      {
          return INSTANCE;
      }
  
      private ServiceRegistration _registeredServer;
  
      private ServiceWatcher _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(final 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 ServiceWatcher();
          context.addServiceListener(_jettyContextHandlerTracker, "(objectclass=" + ContextHandler.class.getName() + ")");
  
          // Create a default jetty instance right now.
          Server defaultServer = DefaultJettyAtJettyHomeHelper.startJettyAtJettyHome(context);
  
         //Create a bundle tracker to help deploy webapps and ContextHandlers
         BundleWatcher bundleTrackerCustomizer = new BundleWatcher();
         bundleTrackerCustomizer.setWaitForDefaultServer(defaultServer != null);
         _webBundleTracker =  new BundleTracker(context, Bundle.ACTIVE | Bundle.STOPPING, bundleTrackerCustomizer);
         bundleTrackerCustomizer.setBundleTracker(_webBundleTracker);
         bundleTrackerCustomizer.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;
         }
     }
 }