/*
    * $Id: SaveSubscriptionAction.java 471754 2006-11-06 14:55:09Z husted $
    *
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *  http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  
  
  package org.apache.struts.webapp.example;
  
  
  import java.lang.reflect.InvocationTargetException;
  
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import javax.servlet.http.HttpSession;
  
  import org.apache.commons.beanutils.PropertyUtils;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.struts.action.Action;
  import org.apache.struts.action.ActionForm;
  import org.apache.struts.action.ActionForward;
  import org.apache.struts.action.ActionMapping;
  import org.apache.struts.util.MessageResources;
  
  
  /**
   * Implementation of <strong>Action</strong> that validates and creates or
   * updates the mail subscription entered by the user.
   *
   * @author Craig R. McClanahan
   * @version $Rev: 471754 $ $Date: 2006-11-06 08:55:09 -0600 (Mon, 06 Nov 2006) $
   */
  
  public final class SaveSubscriptionAction extends Action {
  
  
      // ----------------------------------------------------- Instance Variables
  
  
      /**
       * The <code>Log</code> instance for this application.
       */
      private Log log =
          LogFactory.getLog("org.apache.struts.webapp.Example");
  
  
      // --------------------------------------------------------- Public Methods
  
  
      /**
       * Process the specified HTTP request, and create the corresponding HTTP
       * response (or forward to another web component that will create it).
       * Return an <code>ActionForward</code> instance describing where and how
       * control should be forwarded, or <code>null</code> if the response has
       * already been completed.
       *
       * @param mapping The ActionMapping used to select this instance
       * @param form The optional ActionForm bean for this request (if any)
       * @param request The HTTP request we are processing
       * @param response The HTTP response we are creating
       *
       * @exception Exception if the application business logic throws
       *  an exception
       */
      public ActionForward execute(ActionMapping mapping,
                   ActionForm form,
                   HttpServletRequest request,
                   HttpServletResponse response)
      throws Exception {
  
      // Extract attributes and parameters we will need
      MessageResources messages = getResources(request);
      HttpSession session = request.getSession();
      SubscriptionForm subform = (SubscriptionForm) form;
      String action = subform.getAction();
      if (action == null) {
          action = "?";
          }
          if (log.isDebugEnabled()) {
              log.debug("SaveSubscriptionAction:  Processing " + action +
                        " action");
          }
 
     // Is there a currently logged on user?
     User user = (User) session.getAttribute(Constants.USER_KEY);
     if (user == null) {
             if (log.isTraceEnabled()) {
                 log.trace(" User is not logged on in session "
                           + session.getId());
             }
         return (mapping.findForward("logon"));
         }
 
     // Was this transaction cancelled?
     if (isCancelled(request)) {
             if (log.isTraceEnabled()) {
                 log.trace(" Transaction '" + action +
                           "' was cancelled");
             }
             session.removeAttribute(Constants.SUBSCRIPTION_KEY);
         return (mapping.findForward("success"));
     }
 
     // Is there a related Subscription object?
     Subscription subscription =
       (Subscription) session.getAttribute(Constants.SUBSCRIPTION_KEY);
         if ("Create".equals(action)) {
             if (log.isTraceEnabled()) {
                 log.trace(" Creating subscription for mail server '" +
                           subform.getHost() + "'");
             }
             subscription =
                 user.createSubscription(subform.getHost());
         }
     if (subscription == null) {
             if (log.isTraceEnabled()) {
                 log.trace(" Missing subscription for user '" +
                           user.getUsername() + "'");
             }
         response.sendError(HttpServletResponse.SC_BAD_REQUEST,
                            messages.getMessage("error.noSubscription"));
         return (null);
     }
 
     // Was this transaction a Delete?
     if (action.equals("Delete")) {
             if (log.isTraceEnabled()) {
                 log.trace(" Deleting mail server '" +
                           subscription.getHost() + "' for user '" +
                           user.getUsername() + "'");
             }
             user.removeSubscription(subscription);
         session.removeAttribute(Constants.SUBSCRIPTION_KEY);
             try {
                 UserDatabase database = (UserDatabase)
                     servlet.getServletContext().
                     getAttribute(Constants.DATABASE_KEY);
                 database.save();
             } catch (Exception e) {
                 log.error("Database save", e);
             }
         return (mapping.findForward("success"));
     }
 
     // All required validations were done by the form itself
 
     // Update the persistent subscription information
         if (log.isTraceEnabled()) {
             log.trace(" Populating database from form bean");
         }
         try {
             PropertyUtils.copyProperties(subscription, subform);
         } catch (InvocationTargetException e) {
             Throwable t = e.getTargetException();
             if (t == null)
                 t = e;
             log.error("Subscription.populate", t);
             throw new ServletException("Subscription.populate", t);
         } catch (Throwable t) {
             log.error("Subscription.populate", t);
             throw new ServletException("Subscription.populate", t);
         }
 
         try {
             UserDatabase database = (UserDatabase)
                 servlet.getServletContext().
                 getAttribute(Constants.DATABASE_KEY);
             database.save();
         } catch (Exception e) {
             log.error("Database save", e);
         }
 
     // Remove the obsolete form bean and current subscription
     if (mapping.getAttribute() != null) {
             if ("request".equals(mapping.getScope()))
                 request.removeAttribute(mapping.getAttribute());
             else
                 session.removeAttribute(mapping.getAttribute());
         }
     session.removeAttribute(Constants.SUBSCRIPTION_KEY);
 
     // Forward control to the specified success URI
         if (log.isTraceEnabled()) {
             log.trace(" Forwarding to success page");
         }
     return (mapping.findForward("success"));
 
     }
 
 
 }