/*
    * 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 javax.faces.component;
  
  import java.lang.reflect.Method;
  import java.util.Locale;
  import java.util.MissingResourceException;
  import java.util.ResourceBundle;
  
  import javax.faces.application.FacesMessage;
  import javax.faces.context.FacesContext;
  
  /**
   * @author Manfred Geiler (latest modification by $Author: lu4242 $)
   * @version $Revision: 940131 $ $Date: 2010-05-01 20:29:02 -0500 (Sat, 01 May 2010) $
   */
  class _MessageUtils
  {
      private static final String DETAIL_SUFFIX = "_detail";
      private static final Class[] NO_ARGS = new Class[0];
  
      static void addErrorMessage(FacesContext facesContext,
                                  UIComponent component,
                                  String messageId)
      {
          facesContext.addMessage(component.getClientId(facesContext),
                                  getMessage(facesContext,
                                             facesContext.getViewRoot().getLocale(),
                                             FacesMessage.SEVERITY_ERROR,
                                             messageId,
                                             null));
      }
  
      static void addErrorMessage(FacesContext facesContext,
                                  UIComponent component,
                                  String messageId, Object[] args)
      {
          facesContext.addMessage(component.getClientId(facesContext),
                                  getMessage(facesContext,
                                             facesContext.getViewRoot().getLocale(),
                                             FacesMessage.SEVERITY_ERROR,
                                             messageId,
                                             args));
      }
  
      static void addErrorMessage(FacesContext facesContext,
              UIComponent component, Throwable cause)
      {
          StringBuffer buf = new StringBuffer();
  
          while(cause != null)
          {
              Throwable parentCause = getCause(cause);
              if (parentCause == cause)
              {
                  break;
              }
  
              if(buf.length()>0)
              {
                  buf.append(", ");
              }
              
              buf.append(cause.getLocalizedMessage());
  
              cause = parentCause;
          }
  
          facesContext.addMessage(component.getClientId(facesContext),
                  new FacesMessage(FacesMessage.SEVERITY_ERROR, buf.toString(), buf.toString()));
      }
  
  
      /**
       * Get the cause of an exception, if available. Reflection must be used because
       * JSF11 supports java1.3 but Throwable.getCause was added in java1.4.
       */
      static Throwable getCause(Throwable ex)
      {
          try
          {
              Method causeGetter = ex.getClass().getMethod("getCause", NO_ARGS);
              Throwable cause = (Throwable) causeGetter.invoke(ex, NO_ARGS);
             return cause;
         }
         catch (Exception e1)
         {
             return null;
         }
     }
     
     static FacesMessage getMessage(FacesContext facesContext,
                                    Locale locale,
                                    FacesMessage.Severity severity,
                                    String messageId,
                                    Object args[])
     {
         ResourceBundle appBundle;
         ResourceBundle defBundle;
         String summary;
         String detail;
 
         appBundle = getApplicationBundle(facesContext, locale);
         summary = getBundleString(appBundle, messageId);
         if (summary != null)
         {
             detail = getBundleString(appBundle, messageId + DETAIL_SUFFIX);
         }
         else
         {
             defBundle = getDefaultBundle(facesContext, locale);
             summary = getBundleString(defBundle, messageId);
             if (summary != null)
             {
                 detail = getBundleString(defBundle, messageId + DETAIL_SUFFIX);
             }
             else
             {
                 //Try to find detail alone
                 detail = getBundleString(appBundle, messageId + DETAIL_SUFFIX);
                 if (detail != null)
                 {
                     summary = null;
                 }
                 else
                 {
                     detail = getBundleString(defBundle, messageId + DETAIL_SUFFIX);
                     if (detail != null)
                     {
                         summary = null;
                     }
                     else
                     {
                         //Neither detail nor summary found
                         facesContext.getExternalContext().log("No message with id " + messageId + " found in any bundle");
                         return new FacesMessage(severity, messageId, null);
                     }
                 }
             }
         }
 
         if (args != null && args.length > 0)
         {
             return new _ParametrizableFacesMessage(severity, summary, detail, args, locale);
         }
         else
         {
             return new FacesMessage(severity, summary, detail);
         }
     }
 
     private static String getBundleString(ResourceBundle bundle, String key)
     {
         try
         {
             return bundle == null ? null : bundle.getString(key);
         }
         catch (MissingResourceException e)
         {
             return null;
         }
     }
 
 
     private static ResourceBundle getApplicationBundle(FacesContext facesContext, Locale locale)
     {
         String bundleName = facesContext.getApplication().getMessageBundle();
         if (bundleName != null)
         {
             return getBundle(facesContext, locale, bundleName);
         }
         else
         {
             return null;
         }
     }
 
     private static ResourceBundle getDefaultBundle(FacesContext facesContext,
                                                    Locale locale)
     {
         return getBundle(facesContext, locale, FacesMessage.FACES_MESSAGES);
     }
 
     private static ResourceBundle getBundle(FacesContext facesContext,
                                             Locale locale,
                                             String bundleName)
     {
         try
         {
             //First we try the JSF implementation class loader
             return ResourceBundle.getBundle(bundleName,
                                             locale,
                                             facesContext.getClass().getClassLoader());
         }
         catch (MissingResourceException ignore1)
         {
             try
             {
                 //Next we try the JSF API class loader
                 return ResourceBundle.getBundle(bundleName,
                                                 locale,
                                                 _MessageUtils.class.getClassLoader());
             }
             catch (MissingResourceException ignore2)
             {
                 try
                 {
                     //Last resort is the context class loader
                     return ResourceBundle.getBundle(bundleName,
                                                     locale,
                                                     Thread.currentThread().getContextClassLoader());
                 }
                 catch (MissingResourceException damned)
                 {
                     facesContext.getExternalContext().log("resource bundle " + bundleName + " could not be found");
                     return null;
                 }
             }
         }
     }
 
 }