/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 2001-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Axis" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package org.apache.axis.i18n;

import org.apache.axis.components.logger.LogFactory;
import org.apache.commons.logging.Log;

import java.util.Enumeration;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

/**
 * <p>Wrapper class for resource bundles. Property files are used to store
 * resource strings, which are the only types of resources available.
 * Property files can inherit properties from other files so that
 * a base property file can be used and a small number of properties
 * can be over-ridden by another property file. For example you may
 * create an english version of a resource file named "resource.properties".
 * You then decide that the British English version of all of the properties
 * except one are the same, so there is no need to redefine all of the
 * properties in "resource_en_GB", just the one that is different.</p>
 * <p>The basename is the name of the property file without the ".properties"
 * extension.</p>
 * <p>Properties will be cached for performance.<p>
 * <p>Property values stored in the property files can also contain dynamic
 * variables. Any dynamic variable defined in PropertiesUtil.getVariableValue()
 * can be used (such as {date}), as well as arguments in the form {0}, {1}, etc.
 * Argument values are specified in the various overloaded getString() methods.</p>
 *
 * @author Richard A. Sitze (rsitze@us.ibm.com)
 * @author Karl Moss (kmoss@macromedia.com)
 * @author Glen Daniels (gdaniels@macromedia.com)
 */
public class ProjectResourceBundle extends ResourceBundle
{

   private static Log log =
           LogFactory.getLog(ProjectResourceBundle.class.getName());


   // The static cache of ResourceBundles.
   // The key is the 'basename + locale + default locale'
   // The element is a ResourceBundle object
   private static final Hashtable bundleCache = new Hashtable();

   private static final Locale defaultLocale = Locale.getDefault();

   private final ResourceBundle resourceBundle;
   private final String resourceName;


   protected Object handleGetObject(String key)
           throws MissingResourceException
   {
      if (log.isTraceEnabled())
      {
         log.trace(this.toString() + "::handleGetObject(" + key + ")");
      }
//            return resourceBundle.handleGetObject(key);
      Object obj;
      try
      {
         obj = resourceBundle.getObject(key);
      }
      catch (MissingResourceException e)
      {
         /* catch missing resource, ignore, & return null
          * if this method doesn't return null, then parents
          * are not searched
          */
         obj = null;
      }
      return obj;
   }

   public Enumeration getKeys()
   {
      Enumeration myKeys = resourceBundle.getKeys();
      if (parent == null)
      {
         return myKeys;
      }
      else
      {
         final HashSet set = new HashSet();
         while (myKeys.hasMoreElements())
         {
            set.add(myKeys.nextElement());
         }

         Enumeration pKeys = parent.getKeys();
         while (pKeys.hasMoreElements())
         {
            set.add(pKeys.nextElement());
         }

         return new Enumeration()
         {
            private Iterator it = set.iterator();

            public boolean hasMoreElements()
            {
               return it.hasNext();
            }

            public Object nextElement()
            {
               return it.next();
            }
         };
      }
   }


   /**
    * Construct a new ProjectResourceBundle
    *
    * @param projectName  The name of the project to which the class belongs.
    *                     It must be a proper prefix of the caller's package.
    * @param caller       The calling class.
    *                     This is used to get the package name to further construct
    *                     the basename as well as to get the proper ClassLoader.
    * @param resourceName The name of the resource without the
    *                     ".properties" extension
    * @throws MissingResourceException if projectName is not a prefix of
    *                                  the caller's package name, or if the resource could not be
    *                                  found/loaded.
    */
   public static ProjectResourceBundle getBundle(String projectName,
                                                 String packageName,
                                                 String resourceName)
           throws MissingResourceException
   {
      return getBundle(projectName, packageName, resourceName, null, null, null);
   }

   /**
    * Construct a new ProjectResourceBundle
    *
    * @param projectName  The name of the project to which the class belongs.
    *                     It must be a proper prefix of the caller's package.
    * @param caller       The calling class.
    *                     This is used to get the package name to further construct
    *                     the basename as well as to get the proper ClassLoader.
    * @param resourceName The name of the resource without the
    *                     ".properties" extension
    * @throws MissingResourceException if projectName is not a prefix of
    *                                  the caller's package name, or if the resource could not be
    *                                  found/loaded.
    */
   public static ProjectResourceBundle getBundle(String projectName,
                                                 Class caller,
                                                 String resourceName,
                                                 Locale locale)
           throws MissingResourceException
   {
      return getBundle(projectName,
              caller,
              resourceName,
              locale,
              null);
   }

   /**
    * Construct a new ProjectResourceBundle
    *
    * @param projectName  The name of the project to which the class belongs.
    *                     It must be a proper prefix of the caller's package.
    * @param caller       The calling class.
    *                     This is used to get the package name to further construct
    *                     the basename as well as to get the proper ClassLoader.
    * @param resourceName The name of the resource without the
    *                     ".properties" extension
    * @param locale       The locale
    * @throws MissingResourceException if projectName is not a prefix of
    *                                  the caller's package name, or if the resource could not be
    *                                  found/loaded.
    */
   public static ProjectResourceBundle getBundle(String projectName,
                                                 String packageName,
                                                 String resourceName,
                                                 Locale locale,
                                                 ClassLoader loader)
           throws MissingResourceException
   {
      return getBundle(projectName, packageName, resourceName, locale, loader, null);
   }

   /**
    * Construct a new ProjectResourceBundle
    *
    * @param projectName   The name of the project to which the class belongs.
    *                      It must be a proper prefix of the caller's package.
    * @param caller        The calling class.
    *                      This is used to get the package name to further construct
    *                      the basename as well as to get the proper ClassLoader.
    * @param resourceName  The name of the resource without the
    *                      ".properties" extension
    * @param locale        The locale
    * @param extendsBundle If non-null, then this ExtendMessages will
    *                      default to extendsBundle.
    * @throws MissingResourceException if projectName is not a prefix of
    *                                  the caller's package name, or if the resource could not be
    *                                  found/loaded.
    */
   public static ProjectResourceBundle getBundle(String projectName,
                                                 Class caller,
                                                 String resourceName,
                                                 Locale locale,
                                                 ResourceBundle extendsBundle)
           throws MissingResourceException
   {
      return getBundle(projectName,
              getPackage(caller.getClass().getName()),
              resourceName,
              locale,
              caller.getClass().getClassLoader(),
              extendsBundle);
   }

   /**
    * Construct a new ProjectResourceBundle
    *
    * @param projectName   The name of the project to which the class belongs.
    *                      It must be a proper prefix of the caller's package.
    * @param caller        The calling class.
    *                      This is used to get the package name to further construct
    *                      the basename as well as to get the proper ClassLoader.
    * @param resourceName  The name of the resource without the
    *                      ".properties" extension
    * @param locale        The locale
    * @param extendsBundle If non-null, then this ExtendMessages will
    *                      default to extendsBundle.
    * @throws MissingResourceException if projectName is not a prefix of
    *                                  the caller's package name, or if the resource could not be
    *                                  found/loaded.
    */
   public static ProjectResourceBundle getBundle(String projectName,
                                                 String packageName,
                                                 String resourceName,
                                                 Locale locale,
                                                 ClassLoader loader,
                                                 ResourceBundle extendsBundle)
           throws MissingResourceException
   {
      if (log.isDebugEnabled())
      {
         log.debug("getBundle(" + projectName + ","
                 + packageName + ","
                 + resourceName + ","
                 + String.valueOf(locale) + ",...)");
      }

      Context context = new Context();
      context.setLocale(locale);
      context.setLoader(loader);
      context.setProjectName(projectName);
      context.setResourceName(resourceName);
      context.setParentBundle(extendsBundle);

      packageName = context.validate(packageName);

      ProjectResourceBundle bundle = null;
      try
      {
         bundle = getBundle(context, packageName);
      }
      catch (RuntimeException e)
      {
         log.debug("Exception: ", e);
         throw e;
      }

      if (bundle == null)
      {
         throw new MissingResourceException("Cannot find resource '" +
                 packageName + '.' + resourceName + "'",
                 resourceName, "");
      }

      return bundle;
   }

   /**
    * get bundle...
    * - check cache
    * - try up hierarchy
    * - if at top of hierarchy, use (link to) context.getParentBundle()
    */
   private static synchronized ProjectResourceBundle getBundle(Context context, String packageName)
           throws MissingResourceException
   {
      String cacheKey = context.getCacheKey(packageName);

      ProjectResourceBundle prb = (ProjectResourceBundle)bundleCache.get(cacheKey);

      if (prb == null)
      {
         String name = packageName + '.' + context.getResourceName();
         ResourceBundle rb = context.loadBundle(packageName);
         ResourceBundle parent = context.getParentBundle(packageName);

         if (rb != null)
         {
            prb = new ProjectResourceBundle(name, rb);
            prb.setParent(parent);
            if (log.isDebugEnabled())
            {
               log.debug("Created " + prb + ", linked to parent " + String.valueOf(parent));
            }
         }
         else
         {
            if (parent != null)
            {
               if (parent instanceof ProjectResourceBundle)
               {
                  prb = (ProjectResourceBundle)parent;
               }
               else
               {
                  prb = new ProjectResourceBundle(name, parent);
               }
               if (log.isDebugEnabled())
               {
                  log.debug("Root package not found, cross link to " + parent);
               }
            }
         }

         if (prb != null)
         {
            // Cache the resource
            bundleCache.put(cacheKey, prb);
         }
      }

      return prb;
   }

   private static final String getPackage(String name)
   {
      return name.substring(0, name.lastIndexOf('.')).intern();
   }

   /**
    * Construct a new ProjectResourceBundle
    */
   private ProjectResourceBundle(String name, ResourceBundle bundle)
           throws MissingResourceException
   {
      this.resourceBundle = bundle;
      this.resourceName = name;
   }

   public String getResourceName()
   {
      return resourceName;
   }

   /**
    * Clears the internal cache
    */
   public static void clearCache()
   {
      bundleCache.clear();
   }

   public String toString()
   {
      return resourceName;
   }


   private static class Context
   {
      private Locale _locale;
      private ClassLoader _loader;
      private String _projectName;
      private String _resourceName;
      private ResourceBundle _parent;

      void setLocale(Locale l)
      {
         /* 1. Docs indicate that if locale is not specified,
          *    then the default local is used in it's place.
          * 2. A null value for locale is invalid.
          *
          * Therefore, default...
          */
         _locale = (l == null) ? defaultLocale : l;
      }

      void setLoader(ClassLoader l)
      {
         _loader = (l != null) ? l : this.getClass().getClassLoader();
         // START FIX: http://nagoya.apache.org/bugzilla/show_bug.cgi?id=16868
         if (_loader == null)
         {
            _loader = ClassLoader.getSystemClassLoader();
         }
         // END FIX: http://nagoya.apache.org/bugzilla/show_bug.cgi?id=16868
      }

      void setProjectName(String name)
      {
         _projectName = name.intern();
      }

      void setResourceName(String name)
      {
         _resourceName = name.intern();
      }

      void setParentBundle(ResourceBundle b)
      {
         _parent = b;
      }

      Locale getLocale()
      {
         return _locale;
      }

      ClassLoader getLoader()
      {
         return _loader;
      }

      String getProjectName()
      {
         return _projectName;
      }

      String getResourceName()
      {
         return _resourceName;
      }

      ResourceBundle getParentBundle()
      {
         return _parent;
      }

      String getCacheKey(String packageName)
      {
         String loaderName = (_loader == null) ? "" : (":" + _loader.hashCode());
         return packageName + "." + _resourceName + ":" + _locale + ":" + defaultLocale + loaderName;
      }

      ResourceBundle loadBundle(String packageName)
      {
         try
         {
            return ResourceBundle.getBundle(packageName + '.' + _resourceName,
                    _locale,
                    _loader);
         }
         catch (MissingResourceException e)
         {
            // Deliberately surpressing print stack.. just the string for info.
            log.debug("loadBundle: Ignoring MissingResourceException: " + e.getMessage());
         }
         return null;
      }

      ResourceBundle getParentBundle(String packageName)
      {
         ResourceBundle p;
         if (packageName != _projectName)
         {
            p = getBundle(this, getPackage(packageName));
         }
         else
         {
            p = _parent;
            _parent = null;
         }
         return p;
      }

      String validate(String packageName)
              throws MissingResourceException
      {
         if (_projectName == null || _projectName.length() == 0)
         {
            log.debug("Project name not specified");
            throw new MissingResourceException("Project name not specified",
                    "", "");
         }

         if (packageName == null || packageName.length() == 0)
         {
            log.debug("Package name not specified");
            throw new MissingResourceException("Package not specified",
                    packageName, "");
         }
         packageName = packageName.intern();

         /* Ensure that project is a proper prefix of class.
          * Terminate project name with '.' to ensure proper match.
          */
         if (packageName != _projectName && !packageName.startsWith(_projectName + '.'))
         {
            log.debug("Project not a prefix of Package");
            throw new MissingResourceException("Project '" + _projectName
                    + "' must be a prefix of Package '"
                    + packageName + "'",
                    packageName + '.' + _resourceName, "");
         }

         return packageName;
      }
   }
}
