/*
    * Copyright 2007-2013 smartics, Kronseder & Reiner GmbH
    *
    * Licensed 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 de.smartics.exceptions.i18n.message;
  
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.Enumeration;
  import java.util.Locale;
  import java.util.MissingResourceException;
  import java.util.ResourceBundle;
  import java.util.logging.Logger;
  
  /**
   * Helper to render the messages of an exception in a structured multi-line
   * text.
   */
  class StructuredTextHandler extends AbstractTextHandler
  {
    // ********************************* Fields *********************************
  
    // --- constants ------------------------------------------------------------
  
    /**
     * Reference to the logger for this class.
     */
    private final Logger log = Logger.getLogger(StructuredTextHandler.class
        .getName());
  
    // --- members --------------------------------------------------------------
  
    // ****************************** Initializer *******************************
  
    // ****************************** Constructors ******************************
  
    /**
     * Default constructor.
     *
     * @param bundleBaseName the fully qualified base name of the bundle to use.
     * @param resourceKey the localization key to fetch messages from message
     *          bundles.
     */
    public StructuredTextHandler(final String bundleBaseName,
        final String resourceKey)
    {
      super(bundleBaseName, resourceKey);
    }
  
    // ****************************** Inner Classes *****************************
  
    // ********************************* Methods ********************************
  
    // --- init -----------------------------------------------------------------
  
    // --- get&set --------------------------------------------------------------
  
    // --- business -------------------------------------------------------------
  
    /**
     * Returns the structured and localized message for the given locale,
     * returning each part of information that is provided.
     *
     * @param bean the throwable to construct the localized message.
     * @param locale the locale for which the message is requested.
     * @param loader the loader to read the message bundle.
     * @return returns the localized message of this exception.
     */
    @Override
    public String getMessage(final Object bean, final Locale locale,
        final ClassLoader loader)
    {
      final StringBuilder buffer = new StringBuilder();
      final ResourceBundle messageBundle = fetchMessageBundle(locale, loader);
  
      appendMessage(bean, locale, loader, buffer, MessageType.TITLE, null);
  
      appendWhatHasHappendMessage(bean, locale, loader, buffer, messageBundle);
  
      appendMessage(bean, locale, loader, buffer,
          MessageType.IMPLICATIONS_ON_CURRENT_TASK,
          messageBundle.getString("header.implications"));
  
      appendMessage(bean, locale, loader, buffer, MessageType.WHAT_TO_DO_NOW,
          messageBundle.getString("header.whatToDoNow"));
  
      appendMessage(bean, locale, loader, buffer, MessageType.URL,
          messageBundle.getString("header.url"));
 
     return buffer.toString();
   }
 
   private ResourceBundle fetchMessageBundle(final Locale locale,
       final ClassLoader loader)
   {
     try
     {
       return ResourceBundle.getBundle(
           "de.smartics.exceptions.i18n.message.StructuredTextBundle", locale,
           loader);
     }
     catch (final MissingResourceException e)
     {
       log.warning(String.format(
           "Cannot find resources on classpath. Continue without. Cause: %s",
           e.getMessage()));
       final ResourceBundle bundle = new ResourceBundle()
       {
 
         @Override
         protected Object handleGetObject(final String key)
         {
           return key;
         }
 
         @Override
         public Enumeration<String> getKeys()
         {
           return Collections.enumeration(Arrays.asList(
               "header.whatHasHappened", "header.whatHasHappened.summary",
               "header.whatHasHappened.details", "header.implications",
               "header.whatToDoNow", "header.url"));
         }
       };
       return bundle;
     }
   }
 
   private void appendWhatHasHappendMessage(final Object bean,
       final Locale locale, final ClassLoader loader,
       final StringBuilder buffer, final ResourceBundle messageBundle)
   {
     final String summaryMessage =
         internalGetLocalizedMessage(bean, resourceKey, locale,
             MessageType.SUMMARY, loader);
     final String detailsMessage =
         internalGetLocalizedMessage(bean, resourceKey, locale,
             MessageType.DETAILS, loader);
     if (summaryMessage != null || detailsMessage != null)
     {
       buffer.append(' ')
           .append(messageBundle.getString("header.whatHasHappened"))
           .append('\n');
       if (summaryMessage != null)
       {
         buffer.append("  ");
         if (detailsMessage != null) // NOPMD
         {
           buffer.append(
               messageBundle.getString("header.whatHasHappened.summary"))
               .append(": ");
         }
 
         buffer.append(summaryMessage).append('\n');
       }
       if (detailsMessage != null)
       {
         buffer.append("  ");
         if (summaryMessage != null) // NOPMD
         {
           buffer.append(
               messageBundle.getString("header.whatHasHappened.details"))
               .append(": ");
         }
         buffer.append(detailsMessage).append('\n');
       }
     }
   }
 
   // CHECKSTYLE:OFF
   private void appendMessage(final Object bean, final Locale locale,
       final ClassLoader loader, final StringBuilder buffer,
       final MessageType type, final String headline)
   {
     final String message =
         internalGetLocalizedMessage(bean, resourceKey, locale, type, loader);
     if (message != null)
     {
       if (headline != null)
       {
         buffer.append(' ').append(headline).append("\n  ");
       }
 
       buffer.append(message).append('\n');
     }
   }
   // CHECKSTYLE:OFF
 
   // --- object basics --------------------------------------------------------
 
 }