/**
    * Copyright 2005-2008 the original author or authors.
    *
    * Licensed under the Gnu General Pubic 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.opensource.org/licenses/gpl-license.php
    *
   * 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.
   * See the Gnu General Public License for more details.
   */
  package org.figure8.join.control.action;
  
  import org.figure8.join.control.JoinAction;
  import org.figure8.join.control.form.ConsumerForm;
  import org.figure8.join.core.Configurable;
  import org.figure8.join.core.ContainerContextHandler;
  import org.figure8.join.core.setup.BootstrapUtil;
  import org.figure8.join.core.setup.BootstrapManager;
  import org.figure8.join.core.messaging.JMSConsumerBeanInfo;
  import org.figure8.join.core.messaging.JMSConsumerBeanManager;
  import org.figure8.join.core.messaging.JMSConsumerBeanParameterInfo;
  import org.figure8.join.services.remoting.MessagingService;
  import org.figure8.join.services.remoting.services.BeansHelper;
  import org.figure8.join.services.remoting.beans.RemoteJMSConsumerBeanInfo;
  import org.figure8.join.services.security.InvalidLoginException;
  import org.figure8.join.businessobjects.security.User;
  import org.figure8.join.util.ScriptLogAccessorProxy;
  import org.figure8.join.util.LogUtil;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.beanutils.PropertyUtils;
  import org.apache.struts.action.ActionForm;
  import org.apache.struts.action.ActionForward;
  import org.apache.struts.action.ActionMapping;
  
  import com.caucho.hessian.client.HessianProxyFactory;
  
  import javax.servlet.http.HttpSession;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import java.rmi.RemoteException;
  import java.util.List;
  import java.util.Iterator;
  /**
   * This is a Struts action for managing the event consumers in Join application.
   * @author <a href="mailto:laurent.broudoux@free.fr">Laurent Broudoux</a>
   * @version $Revision: 1.4 $
   *
   * @struts.action path="/consumer" name="consumerForm"
   *                scope="request" parameter="op" validate="true"
   *                input="/pages/mainpage.jsp?body=/jsp/consumers.jsp"
   * @struts.action-forward name="Consumers" path="/jsp/consumers.jsp"
   * @struts.action-forward name="Details" path="/jsp/consumerdetails.jsp"
   * @struts.action-forward name="Parameters" path="/jsp/configurableparameters.jsp"
   */
  public class ConsumerActions extends JoinAction{
  
     // Static -------------------------------------------------------------------
  
     /** Get a commons logger. */
     private static final Log log = LogUtil.getLog(ConsumerActions.class);
  
     /** Operation code for loading a message consumer infos */
     public static final String LOAD_OP = "load";
     /** Operation code for saving a message consumer infos */
     public static final String SAVE_OP = "save";
     /** Operation code for saving a message consumer parameters infos */
     public static final String SAVE_PARAM_OP = "saveParameters";
     /** Operation code for getting details on a message consumer infos */
     public static final String DETAILS_OP = "details";
  
     /**
      * The session scope attribute under which the consumer object
      * currently selected by our logged-in User is stored.
      */
     public static final String CONSUMER_KEY = "consumer";
     /**
      * The session scope attribute under which the retrieved consumers
      * list is stored.
      */
     public static final String CONSUMERS_KEY = "consumers";
     /**
      * The request scope attribute under which is stored the Consumer that
      * has raised a DuplicateEntityException during save of another one.
      */
     public static final String DUPLICATE_CONSUMER_KEY = "duplicate";
  
  
     // Attributes ---------------------------------------------------------------
  
     /** The remote messaging service to use if setup is dissociated */
     protected MessagingService service = null;
     /** The local consumers manager to use if setup is simple */
     protected JMSConsumerBeanManager manager = null;
 
 
    // Constructors -------------------------------------------------------------
 
    /** Creates a new instance of ConsumerActions. */
    public ConsumerActions(){
    }
 
 
    // Override of JoinAction ---------------------------------------------------
 
    /**
     * 
     * @param operation String representing the operation to invoke on Action
     * @param mapping Mapping between forwards name and path for this action
     * @param form The form object containing request parameters
     * @param request The servlet container request wrapper
     * @param response The servlet container response wrapper
     * @return A forward to the next view to render and display
     * @throws Exception such as InfraStructureExceptions ...
     */
    public ActionForward doExecute(String operation, ActionMapping mapping, ActionForm form,
                                   HttpServletRequest request, HttpServletResponse response)
            throws Exception{
       // Trace operation to execute.
       log.debug("doExecute() called for '" + operation + "' operation");
 
       // References cannot be injected so retrieve them.
       initializeManagerOrService();
       // If not specify, set the default display type.
       if (request.getParameter("displayType") == null)
          request.setAttribute("displayType", "all");
 
       try{
          if (LOAD_OP.equals(operation)){
             return loadConsumer(mapping, form, request, response);
          }
          else if (SAVE_OP.equals(operation)){
             return saveConsumer(mapping, form, request, response);
          }
          else if (SAVE_PARAM_OP.equals(operation)){
             return saveConsumerParameters(mapping, form, request, response);
          }
          else if (DETAILS_OP.equals(operation)){
             return getConsumerDetails(mapping, form, request, response);
          }
          else{
             // Default : empty consumers management page.
             request.getSession().removeAttribute(CONSUMER_KEY);
             updateConsumersInRequest(request);
             return mapping.findForward("Consumers");
          }
       }
       catch (InvalidLoginException ile){
          log.error("");
          return mapping.findForward("");
       }
       catch (RemoteException re){
          log.error("");
          return mapping.findForward("");
       }
    }
 
 
    // Protected ----------------------------------------------------------------
 
    /**
     * Load a specified consumer info from datastore and fill form with it.
     * @return A forward to the next view to render and display
     */
    protected ActionForward loadConsumer(ActionMapping mapping, ActionForm form,
                                         HttpServletRequest request, HttpServletResponse response)
          throws Exception{
 
       if (form instanceof ConsumerForm){
          // Get the consumer form & session for storing consumer.
          ConsumerForm cForm = (ConsumerForm)form;
          HttpSession session = request.getSession();
 
          // Get the requested consumer, from local manager or remote service.
          if (manager != null){
             log.debug("Retrieving consumer '" + cForm.getName() + "' from local manager");
             // Use local manager.
             JMSConsumerBeanInfo consumer = manager.getConsumerBeanInfo(cForm.getName());
             session.setAttribute(CONSUMER_KEY, consumer);
             // Copy consumer into the form properties.
             PropertyUtils.copyProperties(cForm, consumer);
          }
          else if (service != null){
             log.debug("Retrieving consumer '" + cForm.getName() + "' from remote service");
             // Use remote service (require login, logout).
             String token = loginToRemoteService(request);
             RemoteJMSConsumerBeanInfo remoteConsumer = service.getConsumerBeanInfo(token, cForm.getName());
             logoutFromRemoteService(token);
             // Create a local consumer for storing in session.
             JMSConsumerBeanInfo consumer = BeansHelper.getLocalObject(remoteConsumer);
             session.setAttribute(CONSUMER_KEY, consumer);
             // Copy consumer into the form properties.
             PropertyUtils.copyProperties(cForm, consumer);
          }
 
          // Forward after having filled request with consumers.
          updateConsumersInRequest(request);
          return mapping.findForward("Consumers");
       }
       // This should not happen...
       return null;
    }
 
    /**
     * Save a consumer into datastore. The consumer may be an already existing one or a
     * new one (this is indeed a create or update method).
     * @return A forward to the next view to render and display
     */
    protected ActionForward saveConsumer(ActionMapping mapping, ActionForm form,
                                         HttpServletRequest request, HttpServletResponse response)
          throws Exception{
 
       if (form instanceof ConsumerForm){
          // Get the consumer form.
          ConsumerForm cForm = (ConsumerForm)form;
          // Is there a consumer to update in session ?
          HttpSession session = request.getSession();
          JMSConsumerBeanInfo consumer = (JMSConsumerBeanInfo)session.getAttribute(CONSUMER_KEY);
 
          // Create a new consumer or populate existing with form.
          if (consumer == null){
             log.info("Creation of a new JMSConsumerBeanInfo with name: " + cForm.getName());
             consumer = new JMSConsumerBeanInfo(cForm.getName(), cForm.getSelector(), cForm.getDestination(),
                     cForm.getConsumerBeanClass());
             consumer.setActive(cForm.isActive());
             consumer.setThreadSafe(cForm.isThreadSafe());
          }
          else{
             log.info("Update of existing JMSConsumerBeanInfo having name: " + cForm.getName());
             PropertyUtils.copyProperties(consumer, cForm);
          }
 
          // Save the consumer, using local manager or remote service.
          if (manager != null){
             log.debug("Saving consumer '" + cForm.getName() + "' using local manager");
             // Use local manager.
             manager.saveConsumerBeanInfo(consumer);
          }
          else if (service != null){
             log.debug("Saving consumer '" + cForm.getName() + "' using remote service");
             // Use remote service (require login, logout).
             String token = loginToRemoteService(request);
             service.saveConsumerBeanInfo(token, BeansHelper.getRemoteObject(consumer));
             logoutFromRemoteService(token);
          }
 
          // Forward depending of configurable nature of consumer class.
          if (consumer.getJMSConsumerBean() instanceof Configurable){
             session.setAttribute(CONSUMER_KEY, consumer);
             // Give the configurable form what it need.
             request.setAttribute(OP_PARAMETER, SAVE_PARAM_OP);
             request.setAttribute("configurableId", consumer.getName());
             request.setAttribute("configurable", consumer.getJMSConsumerBean());
             request.setAttribute("action", "consumer");
 
             // Retrieve consumer's parameters and fill form.
             List parameters = consumer.getConsumerParameterInfos();
             for (int i=0; i < parameters.size(); i++)
                cForm.addParameter((JMSConsumerBeanParameterInfo)parameters.get(i));
 
             return mapping.findForward("Parameters");
          }
 
          // Remove form and session attribute if present.
          session.removeAttribute(CONSUMER_KEY);
          updateConsumersInRequest(request);
          removeObsoleteForm(mapping, request);
          return mapping.findForward("Consumers");
       }
       // This should not happen...
       return null;
    }
 
    /**
     * Save a consumer parameters into datastore. The consumer is an already existing one.
     * @return A forward to the next view to render and display
     */
    protected ActionForward saveConsumerParameters(ActionMapping mapping, ActionForm form,
                                                   HttpServletRequest request, HttpServletResponse response)
          throws Exception{
 
       if (form instanceof ConsumerForm){
          // Get the consumer form.
          ConsumerForm cForm = (ConsumerForm)form;
          // Is there a consumer to update in session ?
          HttpSession session = request.getSession();
          JMSConsumerBeanInfo consumer = (JMSConsumerBeanInfo)session.getAttribute(CONSUMER_KEY);
 
          if (consumer != null){
             log.info("Adding JMSConsumerBeanParameterInfo to consumer: " + consumer.getName());
             // Remove all existing parameters.
             consumer.getConsumerParameterInfos().clear();
 
             // Browse parameters present in form.
             Iterator parameters = cForm.getParameters().keySet().iterator();
             while (parameters != null && parameters.hasNext()){
                // Retrieve name, value pairs.
                String name = (String)parameters.next();
                String value = (String)cForm.getMappedParameter(name);
                if (log.isDebugEnabled())
                   log.debug("Adding a consumer parameter: " + name + "=" + value);
                // Add a new parameter info to consume.
                JMSConsumerBeanParameterInfo paramInfo = new JMSConsumerBeanParameterInfo(name, value);
                consumer.addConsumerParameterInfo(paramInfo);
             }
 
             // Update the consumer, using local manager or remote service.
             if (manager != null){
                log.debug("Saving consumer '" + cForm.getName() + "' parameters using local manager");
                // Use local manager.
                manager.saveConsumerBeanInfo(consumer);
             }
             else if (service != null){
                log.debug("Saving consumer '" + cForm.getName() + "' parameters using remote service");
                // Use remote service (require login, logout).
                String token = loginToRemoteService(request);
                service.saveConsumerBeanInfo(token, BeansHelper.getRemoteObject(consumer));
                logoutFromRemoteService(token);
             }
          }
 
          // Forward after having updated consumers in request.
          updateConsumersInRequest(request);
          // Remove form and session attribute if present.
          session.removeAttribute(CONSUMER_KEY);
          removeObsoleteForm(mapping, request);
          return mapping.findForward("Consumers");
       }
       // This should not happen...
       return null;
    }
 
    /**
     * Get all the details from registered consumer, including its parameters and execution log files
     * @return A forward to the next view to render and display
     */
    protected ActionForward getConsumerDetails(ActionMapping mapping, ActionForm form,
                                               HttpServletRequest request, HttpServletResponse response)
          throws Exception{
 
       if (form instanceof ConsumerForm){
          ConsumerForm cForm = (ConsumerForm)form;
 
          // Get the requested consumer, from local manager or remote service.
          if (manager != null){
             JMSConsumerBeanInfo consumer = manager.getConsumerBeanInfo(cForm.getName());
             request.setAttribute(CONSUMER_KEY, consumer);
          }
          else if (service != null){
             String token = loginToRemoteService(request);
             RemoteJMSConsumerBeanInfo consumer = service.getConsumerBeanInfo(token, cForm.getName());
             logoutFromRemoteService(token);
             request.setAttribute(CONSUMER_KEY, consumer);
          }
          // Get information on execution logs.
          ScriptLogAccessorProxy proxy = ScriptLogAccessorProxy.getInstance();
          List logInfos = proxy.getScriptLogInfos(cForm.getName(), "JMSAdapter");
          request.setAttribute("scriptLogInfos", logInfos);
 
          // Forward to details.
          return mapping.findForward("Details");
       }
       // This should not happen...
       return null;
    }
 
    /**
     * Update the consumers definitions collection within request.
     * @param request The servlet container request wrapper
     * @throws Exception if consumers cannot be refreshed
     */
    protected void updateConsumersInRequest(HttpServletRequest request) throws Exception{
       if (manager != null){
          // Use local manager.
          request.setAttribute(CONSUMERS_KEY, manager.getConsumerBeanInfos());
       }
       else if (service != null){
          // Use remote service (require login, logout).
          String token = loginToRemoteService(request);
          request.setAttribute(CONSUMERS_KEY, service.getConsumerBeanInfos(token));
          logoutFromRemoteService(token);
       }
    }
 
    /**
     * Initialize the local consumer manager or the remote service depending
     * on the application setup and the application side we are on.
     * @throws Exception if manager cannot be found or remote service is not available
     */
    protected void initializeManagerOrService() throws Exception{
       if (manager == null && service == null){
          BootstrapManager bootstrapManager = BootstrapUtil.getBootstrapManager();
          // Use remote service only if we are on synchronous side of a dissociate setup.
          if (bootstrapManager.isDissociatedSetup() && bootstrapManager.isSynchronousSide()){
             String url = bootstrapManager.getOtherSideUrl() + "/remoting/hessian/MessagingService";
             log.info("Connecting to remote MessagingService using url: " + url);
             HessianProxyFactory proxyFactory = new HessianProxyFactory();
             service = (MessagingService)proxyFactory.create(MessagingService.class, url);
          }
          else{
             // Use local manager provided by container facility.
             log.info("Looking up local JMSConsumerBeanManager using 'jmsConsumerBeanManager' component");
             ContainerContextHandler handler = ContainerContextHandler.getInstance();
             manager = (JMSConsumerBeanManager)handler.getComponent("jmsConsumerBeanManager");
          }
       }
    }
 
 
    // Private ------------------------------------------------------------------
 
    /** Login for using remote service. */
    private String loginToRemoteService(HttpServletRequest request) throws InvalidLoginException, RemoteException{
       // Extract user and its clear password from request.
       User user = getUserContainer(request).getView().getUser();
       String pwd = getUserContainer(request).getView().getClearPassword();
       // Logon to remote service, get a token.
       String token = service.login(user.getLogin(), pwd);
       return token;
    }
 
    /** Logout from remote service. */
    private void logoutFromRemoteService(String token) throws RemoteException{
       service.logout(token);
    }
 }