/*
    * 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 javax.el.ValueExpression;
  import javax.faces.application.FacesMessage;
  import javax.faces.context.FacesContext;
  
  import java.util.Locale;
  import java.util.MissingResourceException;
  import java.util.ResourceBundle;
  
  class _MessageUtils
  {
      private static final String DETAIL_SUFFIX = "_detail";
  
      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)
      {
          facesContext.addMessage(component.getClientId(facesContext),
                  new FacesMessage(FacesMessage.SEVERITY_ERROR, cause
                          .getLocalizedMessage(), cause.getLocalizedMessage()));
      }
  
      
      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();
         return bundleName != null ? getBundle(facesContext, locale, bundleName) : 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,
                                                     _ClassUtils.getContextClassLoader());
                 }
                 catch (MissingResourceException damned)
                 {
                     facesContext.getExternalContext().log("resource bundle " + bundleName + " could not be found");
                     return null;
                 }
             }
         }
     }
     
     static Object getLabel(FacesContext facesContext, UIComponent component)
     {
         Object label = component.getAttributes().get("label");
         ValueExpression expression = null;
         if (label != null && 
             label instanceof String && ((String)label).length() == 0 )
         {
             // Note component.getAttributes().get("label") internally try to 
             // evaluate the EL expression for the label, but in some cases, 
             // when PSS is disabled and f:loadBundle is used, when the view is 
             // restored the bundle is not set to the EL expression returns an 
             // empty String. It is not possible to check if there is a 
             // hardcoded label, but we can check if there is
             // an EL expression set, so the best in this case is use that, and if
             // there is an EL expression set, use it, otherwise use the hardcoded
             // value. See MYFACES-3591 for details.
             expression = component.getValueExpression("label");
             if (expression != null)
             {
                 // Set the label to null and use the EL expression instead.
                 label = null;
             }
         }
             
         if(label != null)
         {
             return label;
         }
         
         expression = (expression == null) ? component.getValueExpression("label") : expression;
         if(expression != null)
         {
             return expression;
         }
         
         //If no label is not specified, use clientId
         return component.getClientId( facesContext );
     }
 }