/**
    * This file Copyright (c) 2003-2010 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.cms.util;
  
  import info.magnolia.context.Context;
  import info.magnolia.context.MgnlContext;
  
  import org.apache.commons.lang.StringUtils;
  
  
  /**
   * Stores a message in the request. This message can get alerted from the interface. This is used for example to alert
   * activation errors.
   * @author philipp
   * @version $Revision: 32667 $ ($Author: gjoseph $)
   */
  public class AlertUtil {
  
      /**
       * Util: do not instantiate.
       */
      private AlertUtil() {
      }
  
      /**
       * Store the message. Does not overwrite an already existing message.
       * @param msg
       */
      public static void setMessage(String msg) {
          setMessage(msg, MgnlContext.getInstance());
      }
  
      public static void setMessage(String msg, Context ctx) {
          if (!isMessageSet(ctx)) {
              ctx.setAttribute(Context.ATTRIBUTE_MESSAGE, msg, Context.LOCAL_SCOPE);
          }
      }
  
      /**
       * create a message containing the exception message
       * @param msg
       * @param e
       */
      public static void setMessage(String msg, Exception e) {
          setMessage(msg, e, MgnlContext.getInstance());
      }
  
      public static void setMessage(String msg, Exception e, Context ctx) {
          setMessage(msg + " : " + getExceptionMessage(e), ctx);
      }
  
      public static void setException(String msg, Exception e) {
          setException(msg, e, MgnlContext.getInstance());
      }
  
      public static void setException(String msg, Exception e, Context ctx) {
          setMessage(msg + " : " + getExceptionMessage(e), ctx);
          setException(e, ctx);
      }
  
      /**
       * Checks if there is a message set
       * @param request
       * @return true if set
       */
  
      public static boolean isMessageSet() {
          return isMessageSet(MgnlContext.getInstance());
     }
 
     public static boolean isMessageSet(Context ctx) {
         return StringUtils.isNotEmpty((String) ctx.getAttribute(Context.ATTRIBUTE_MESSAGE, Context.LOCAL_SCOPE));
     }
 
     /**
      * Store the exception. Does not overwrite an already existing one.
      */
     public static void setException(Exception e) {
         setException(e, MgnlContext.getInstance());
     }
 
     public static void setException(Exception e, Context ctx) {
         if (!isExceptionSet(ctx)) {
             ctx.setAttribute(Context.ATTRIBUTE_EXCEPTION, e, Context.LOCAL_SCOPE);
             // has only an effect if not yet set
             setMessage(getExceptionMessage(e), ctx);
         }
     }
 
     /**
      * Checks if there is a message set
      * @return true if set
      */
     public static boolean isExceptionSet() {
         return isExceptionSet(MgnlContext.getInstance());
     }
 
     public static boolean isExceptionSet(Context ctx) {
         return ctx.getAttribute(Context.ATTRIBUTE_EXCEPTION, Context.LOCAL_SCOPE) != null;
     }
 
     /**
      * Returns the current set message
      * @param request
      * @return the message
      */
     public static String getMessage() {
         return getMessage(MgnlContext.getInstance());
     }
 
     public static String getMessage(Context ctx) {
         return (String) ctx.getAttribute(Context.ATTRIBUTE_MESSAGE, Context.LOCAL_SCOPE);
     }
 
     /**
      * Creates a string message out of an exception. Handles nested exceptions.
      * @param e
      * @return the message
      */
     public static String getExceptionMessage(Exception e) {
         String message = e.getMessage();
         if (StringUtils.isEmpty(message)) {
             if (e.getCause() != null) {
                 message = e.getCause().getMessage();
             }
             if (message == null) {
                 message = StringUtils.EMPTY;
             }
         }
         return message;
     }
 
     public static Exception getException() {
         return getException(MgnlContext.getInstance());
     }
 
     public static Exception getException(Context ctx) {
         return (Exception) ctx.getAttribute(Context.ATTRIBUTE_EXCEPTION, Context.LOCAL_SCOPE);
     }
 }