/*
    * Copyright (C) 2013 4th Line GmbH, Switzerland
    *
    * The contents of this file are subject to the terms of either the GNU
    * Lesser General Public License Version 2 or later ("LGPL") or the
    * Common Development and Distribution License Version 1 or later
    * ("CDDL") (collectively, the "License"). You may not use this file
    * except in compliance with the License. See LICENSE.txt for more
    * information.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   */
  
  package org.fourthline.cling.protocol.sync;
  
  import org.fourthline.cling.model.NetworkAddress;
  import org.fourthline.cling.model.gena.RemoteGENASubscription;
  import org.fourthline.cling.model.message.StreamResponseMessage;
  import org.fourthline.cling.model.message.gena.IncomingSubscribeResponseMessage;
  import org.fourthline.cling.model.message.gena.OutgoingSubscribeRequestMessage;
  import org.fourthline.cling.UpnpService;
  import org.fourthline.cling.protocol.SendingSync;
  import org.fourthline.cling.transport.RouterException;
  
  import java.util.List;
  import java.util.logging.Logger;
  
  /**
   * Establishing a GENA event subscription with a remote host.
   * <p>
   * Calls the {@link org.fourthline.cling.model.gena.RemoteGENASubscription#establish()} method
   * if the subscription request was responded to correctly.
   * </p>
   * <p>
   * The {@link org.fourthline.cling.model.gena.RemoteGENASubscription#fail(org.fourthline.cling.model.message.UpnpResponse)}
   * method will be called if the request failed. No response from the remote host is indicated with
   * a <code>null</code> argument value. Note that this is also the response if the subscription has
   * to be aborted early, when no local stream server for callback URL creation is available. This is
   * the case when the local network transport layer is switched off, subscriptions will fail
   * immediately with no response.
   * </p>
   *
   * @author Christian Bauer
   */
  public class SendingSubscribe extends SendingSync<OutgoingSubscribeRequestMessage, IncomingSubscribeResponseMessage> {
  
      final private static Logger log = Logger.getLogger(SendingSubscribe.class.getName());
  
      final protected RemoteGENASubscription subscription;
  
      public SendingSubscribe(UpnpService upnpService,
                              RemoteGENASubscription subscription,
                              List<NetworkAddress> activeStreamServers) {
          super(
              upnpService,
              new OutgoingSubscribeRequestMessage(
                  subscription,
                  subscription.getEventCallbackURLs(
                      activeStreamServers,
                      upnpService.getConfiguration().getNamespace()
                  ),
                  upnpService.getConfiguration().getEventSubscriptionHeaders(subscription.getService())
              )
          );
  
          this.subscription = subscription;
      }
  
      protected IncomingSubscribeResponseMessage executeSync() throws RouterException {
  
          if (!getInputMessage().hasCallbackURLs()) {
              log.fine("Subscription failed, no active local callback URLs available (network disabled?)");
              getUpnpService().getConfiguration().getRegistryListenerExecutor().execute(
                  new Runnable() {
                      public void run() {
                          subscription.fail(null);
                      }
                  }
              );
              return null;
          }
  
          log.fine("Sending subscription request: " + getInputMessage());
  
          try {
              // register this pending Subscription to bloc if the notification is received before the
              // registration result.
              getUpnpService().getRegistry().registerPendingRemoteSubscription(subscription);
  
              StreamResponseMessage response = null;
              try {
                  response = getUpnpService().getRouter().send(getInputMessage());
              } catch (RouterException ex) {
                  onSubscriptionFailure();
                  return null;
              }
  
             if (response == null) {
                 onSubscriptionFailure();
                 return null;
             }
 
             final IncomingSubscribeResponseMessage responseMessage = new IncomingSubscribeResponseMessage(response);
 
             if (response.getOperation().isFailed()) {
                 log.fine("Subscription failed, response was: " + responseMessage);
                 getUpnpService().getConfiguration().getRegistryListenerExecutor().execute(
                     new Runnable() {
                         public void run() {
                             subscription.fail(responseMessage.getOperation());
                         }
                     }
                 );
             } else if (!responseMessage.isValidHeaders()) {
                 log.severe("Subscription failed, invalid or missing (SID, Timeout) response headers");
                 getUpnpService().getConfiguration().getRegistryListenerExecutor().execute(
                     new Runnable() {
                         public void run() {
                             subscription.fail(responseMessage.getOperation());
                         }
                     }
                 );
             } else {
 
                 log.fine("Subscription established, adding to registry, response was: " + response);
                 subscription.setSubscriptionId(responseMessage.getSubscriptionId());
                 subscription.setActualSubscriptionDurationSeconds(responseMessage.getSubscriptionDurationSeconds());
 
                 getUpnpService().getRegistry().addRemoteSubscription(subscription);
 
                 getUpnpService().getConfiguration().getRegistryListenerExecutor().execute(
                     new Runnable() {
                         public void run() {
                             subscription.establish();
                         }
                     }
                 );
 
             }
             return responseMessage;
         } finally {
             getUpnpService().getRegistry().unregisterPendingRemoteSubscription(subscription);
         }
     }
 
     protected void onSubscriptionFailure() {
         log.fine("Subscription failed");
         getUpnpService().getConfiguration().getRegistryListenerExecutor().execute(
             new Runnable() {
                 public void run() {
                     subscription.fail(null);
                 }
             }
         );
     }
 }