/*

  *   SONEWS News Server

  *   see AUTHORS for the list of contributors

  *

  *   This program is free software: you can redistribute it and/or modify

  *   it under the terms of the GNU General Public License as published by

  *   the Free Software Foundation, either version 3 of the License, or

  *   (at your option) any later version.

  *

  *   This program is distributed in the hope that it will be useful,

  *   but WITHOUT ANY WARRANTY; without even the implied warranty of

  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  *   GNU General Public License for more details.

  *

  *   You should have received a copy of the GNU General Public License

  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.

  */

 package org.sonews.config;

 import java.util.logging.Level;

 import org.sonews.util.Log;

 import org.sonews.storage.StorageBackendException;

 import org.sonews.storage.StorageManager;

 import org.sonews.util.TimeoutMap;

 /**

  * Provides access to the program wide configuration that is stored within

  * the server's database.

  * @author Christian Lins

  * @since sonews/0.5.0

  */

 class BackendConfig extends AbstractConfig

 {

 	private static BackendConfig instance = new BackendConfig();

 	public static BackendConfig getInstance()

 	{

 		return instance;

 	}

 	private final TimeoutMap<String, String> values = new TimeoutMap<String, String>();

 	private BackendConfig()

 	{

 		super();

 	}

 	/**

 	 * Returns the config value for the given key or the defaultValue if the

 	 * key is not found in config.

 	 * @param key

 	 * @param defaultValue

 	 * @return

 	 */

 	@Override

 	public String get(String key, String defaultValue)

 	{

 		try {

 			String configValue = values.get(key);

 			if (configValue == null) {

 				if (StorageManager.current() == null) {

 					Log.get().warning("BackendConfig not available, using default.");

 					return defaultValue;

 				}

 				configValue = StorageManager.current().getConfigValue(key);

 				if (configValue == null) {

 					return defaultValue;

 				} else {

 					values.put(key, configValue);

 					return configValue;

 				}

 			} else {

 				return configValue;

 			}

 		} catch (StorageBackendException ex) {

 			Log.get().log(Level.SEVERE, "Storage backend problem", ex);

 			return defaultValue;

 		}

 	}

 	/**

 	 * Sets the config value which is identified by the given key.

 	 * @param key

 	 * @param value

 	 */

 	public void set(String key, String value)

 	{

 		values.put(key, value);

 		try {

 			// Write values to database

 			StorageManager.current().setConfigValue(key, value);

 		} catch (StorageBackendException ex) {

 			ex.printStackTrace();

 		}

 	}

 }