/*
    * Copyright 2003 - 2014 The eFaps Team
    *
    * 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.
   *
   * Revision:        $Rev$
   * Last Changed:    $Date$
   * Last Changed By: $Author$
   */
  
  
  package org.efaps.admin;
  
  import java.io.File;
  import java.net.URI;
  import java.util.Collections;
  import java.util.Map;
  
  /**
   * Class used to set the configuration of an single instance of eFaps.
   * It can only be instantiated once. If it was not instantiated before the
   * first access a default instance of <code>AppConfigHandler</code> will be
   * created.
   *
   * @author The eFaps Team
   * @version $Id$
   */
  public final class AppConfigHandler
  {
      /**
       * Enum used to have a String representation of the config key,
       * that can be used by an webapp initialization parameter.
       */
      public enum Parameter
      {
          /**
           * Deactivate the AccessCache.
           */
          ACCESSCACHE_DEACTIVATE("org.efaps.application.config.AccessCache.deactivate"),
  
          /**
           * Deactivate the AccessCache.
           */
          QUERYCACHE_DEACTIVATE("org.efaps.application.config.QueryCache.deactivate"),
  
          /**
           * The id of this system as needed by the GeneralInstance mechanism.
           */
          SYSTEMID("org.efaps.application.config.SystemID"),
  
          /**
           * The id of this system as needed by the GeneralInstance mechanism.
           */
          TEMPFOLDER("org.efaps.application.config.TempFolder");
  
          /**
           * Key of the enum instance.
           */
          private String key;
  
          /**
           * @param _key key of the enum instance.
           */
          private Parameter(final String _key)
          {
              this.key = _key;
          }
  
          /**
           * Getter method for the instance variable {@link #key}.
           *
           * @return value of instance variable {@link #key}
           */
          public String getKey()
          {
              return this.key;
          }
      }
  
      /**
       * Singleton instance.
       */
      private static AppConfigHandler HANDLER;
  
      /**
       * Possibility to deactivate the AccessCache.
       */
      private final boolean accessCacheDeactivated;
  
     /**
      * Possibility to deactivate the AccessCache.
      */
     private final boolean queryCacheDeactivated;
 
     /**
      *  The id of this system as needed by the GeneralInstance mechanism.
      */
     private final int systemID;
 
     /**
      * URI to the temp folder used by eFaps.
      */
     private final URI tmpURI;
 
     /**
      * Singleton Constructor.
      * @param _values values for the init
      */
     private AppConfigHandler(final Map<String, String> _values)
     {
         this.accessCacheDeactivated =  "true".equalsIgnoreCase(_values.get(Parameter.ACCESSCACHE_DEACTIVATE.getKey()));
         this.queryCacheDeactivated =  "true".equalsIgnoreCase(_values.get(Parameter.QUERYCACHE_DEACTIVATE.getKey()));
         if (_values.containsKey(Parameter.SYSTEMID.getKey())) {
             this.systemID = Integer.parseInt(_values.get(Parameter.SYSTEMID.getKey()));
         } else {
             this.systemID = 0;
         }
         if (_values.containsKey(Parameter.TEMPFOLDER.getKey())) {
             this.tmpURI = URI.create(_values.get(Parameter.TEMPFOLDER.getKey()));
         } else {
             this.tmpURI = null;
         }
     }
 
     /**
      * Getter method for the instance variable {@link #accessCacheDeactivated}.
      *
      * @return value of instance variable {@link #accessCacheDeactivated}
      */
     public boolean isAccessCacheDeactivated()
     {
         return this.accessCacheDeactivated;
     }
 
     /**
      * Getter method for the instance variable {@link #queryCacheDeactivated}.
      *
      * @return value of instance variable {@link #queryCacheDeactivated}
      */
     public boolean isQueryCacheDeactivated()
     {
         return this.queryCacheDeactivated;
     }
 
     /**
      * Getter method for the instance variable {@link #systemID}.
      *
      * @return value of instance variable {@link #systemID}
      */
     public int getSystemID()
     {
         return this.systemID;
     }
 
     /**
      * @return if defined the tempfolder for eFaps, else null
      */
     public File getTempFolder()
     {
         File ret;
         if (this.tmpURI == null) {
             ret = null;
         } else {
             ret = new File(this.tmpURI);
         }
         return ret;
     }
 
     /**
      * Init the Handler. Can only be executed once.
      * @param _values values for the init
      */
     public static void init(final Map<String, String> _values)
     {
         if (AppConfigHandler.HANDLER == null) {
             AppConfigHandler.HANDLER = new AppConfigHandler(_values);
         }
     }
 
     /**
      * Is the Handler initialized.
      *
      * @return true if already the Handler is set
      */
     public static boolean initialized()
     {
         return AppConfigHandler.HANDLER != null;
     }
 
     /**
      * @return the instance of the AppConfigHandler
      */
     public static AppConfigHandler get()
     {
         if (!AppConfigHandler.initialized()) {
             AppConfigHandler.init(Collections.<String, String>emptyMap());
         }
         return AppConfigHandler.HANDLER;
     }
 }