/**
    * Copyright 2005-2006 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.DefaultForm;
  import org.figure8.join.core.setup.ApplicationConfig;
  import org.figure8.join.util.LogUtil;
  
  import org.apache.commons.logging.Log;
  import org.apache.struts.action.ActionForm;
  import org.apache.struts.action.ActionForward;
  import org.apache.struts.action.ActionMapping;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import java.util.List;
  import java.util.ArrayList;
  import java.util.Properties;
  import java.util.StringTokenizer;
  import java.io.InputStream;
  /**
   * @author <a href="mailto:laurent.broudoux@free.fr">Laurent Broudoux</a>
   * @version $Revision: 1.1 $
   *
   * @struts.action path="/configuration" name="defaultForm"
   *                scope="request" parameter="op" validate="true"
   *                input="/pages/mainpage.jsp?body=/jsp/configuration.jsp"
   * @struts.action-forward name="Configuration" path="/jsp/configuration.jsp"
   */
  public class ConfigurationActions extends JoinAction{
  
     // Static -------------------------------------------------------------------
  
     /** Get a commons logger */
     private static final Log log = LogUtil.getLog(ConfigurationActions.class);
  
     /** Operation code for saving all edited configuration properties */
     public static final String SAVE_OP = "save";
  
     /** Constant representing the property containing all configurable properties */
     public static final String CONFIG_PROPERTIES_LIST = "join.properties";
     /** Constant for path to properties file containing all configurable properties */
     public static final String CONFIG_PROPERTIES_FILE = "/join-config.properties";
  
     /**
      * Name of the request attribute key used for storing the list of
      * configuratble properties names.
      */
     public static final String PROPERTIES_KEY = "properties";
  
  
     // Attributes ---------------------------------------------------------------
  
     /** A flag telling if properties have already been read */
     private boolean initialized = false;
     /** The list of properties configurable through this action */
     private List propertiesNames = new ArrayList();
     /** The whole configuration properties and their description loaded from file */
     private Properties configurationProperties = new Properties();
  
     /** The Join application configuration handler */
     private ApplicationConfig applicationConfig = null;
  
  
     // Constructors -------------------------------------------------------------
  
     /** Creates a new instance of ConfigurationActions */
     public ConfigurationActions(){
     }
  
  
     // Public -------------------------------------------------------------------
  
     /** @param applicationConfig The application configuration handler object */
     public void setApplicationConfig(ApplicationConfig applicationConfig){
        this.applicationConfig = applicationConfig;
     }
  
  
     // Implementation 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");
 
       if (form instanceof DefaultForm){
          // Call initialization method.
          initializeConfigurationProperties();
 
          if (SAVE_OP.equals(operation)){
             // Update all configurable properties from values in request.
             for (int i=0; i<propertiesNames.size(); i++){
                String key = (String)propertiesNames.get(i);
                String value = request.getParameter(key);
                applicationConfig.setProperty(key, value);
                if (log.isDebugEnabled())
                   log.debug("Setting property '" + key + "' to value: " + value);
             }
             // Save the application config in Xml file.
             log.info("Saving application configuration with new values...");
             applicationConfig.save();
          }
 
          // In all the case, provide properties list.
          request.setAttribute(PROPERTIES_KEY, propertiesNames);
          // Provide also their value, default value and description.
          for (int i=0; i<propertiesNames.size(); i++){
             // Take care of current value.
             String key = (String)propertiesNames.get(i);
             String value = (String)applicationConfig.getProperty(key);
             // Take care of default value.
             String defValue = configurationProperties.getProperty(key + ".default");
             request.setAttribute(key + ".default", defValue);
             // Take care of description.
             String description = configurationProperties.getProperty(key + ".description");
             request.setAttribute(key + ".description", description);
 
             // Assign current or default value.
             if (value != null && value.length() > 0)
                request.setAttribute(key, value);
             else request.setAttribute(key, defValue);
          }
 
          return mapping.findForward("Configuration");
       }
       // This should not happen...
       return null;
    }
 
 
    // Private ------------------------------------------------------------------
 
    /**
     * Initialize configuration properties by loading and parsing the
     * CONFIG_PROPERTIES_FILE. Property providing list of configurable properties
     * is then tokenized into <b>propertiesName</b>.
     */
    private void initializeConfigurationProperties(){
       if (!initialized){
          InputStream is = this.getClass().getResourceAsStream(CONFIG_PROPERTIES_FILE);
 
          try {configurationProperties.load(is);}
          catch (Exception e){
             // Log and wrap into runtime exception.
             log.error(CONFIG_PROPERTIES_FILE + " is not loadable into properties");
             log.error("Here's the detailed message: " + e.getMessage());
             throw new IllegalStateException(CONFIG_PROPERTIES_FILE + " cannot be found or reached");
          }
          // Get properties list.
          String propertiesList = configurationProperties.getProperty(CONFIG_PROPERTIES_LIST);
 
          // Browse and tokenizer properties list.
          StringTokenizer tokenizer = new StringTokenizer(propertiesList, ",");
          while (tokenizer != null && tokenizer.hasMoreTokens()){
             String configurationProperty = tokenizer.nextToken();
             propertiesNames.add(configurationProperty);
          }
          // Update init flag.
          initialized = true;
       }
    }
 }