/*

  *   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.io.FileInputStream;

 import java.io.FileNotFoundException;

 import java.io.FileOutputStream;

 import java.io.IOException;

 import java.util.Properties;

 /**

  * Manages the bootstrap configuration. It MUST contain all config values

  * that are needed to establish a database connection.

  * For further configuration values use the Config class instead as that class

  * stores its values within the database.

  * @author Christian Lins

  * @since sonews/0.5.0

  */

 class FileConfig extends AbstractConfig

 {

 	private static final Properties defaultConfig = new Properties();

 	private static FileConfig instance = null;

 	static {

 		// Set some default values

 		defaultConfig.setProperty(Config.STORAGE_DATABASE, "jdbc:mysql://localhost/sonews");

 		defaultConfig.setProperty(Config.STORAGE_DBMSDRIVER, "com.mysql.jdbc.Driver");

 		defaultConfig.setProperty(Config.STORAGE_USER, "sonews_user");

 		defaultConfig.setProperty(Config.STORAGE_PASSWORD, "mysecret");

 		defaultConfig.setProperty(Config.DEBUG, "false");

 	}

 	/**

 	 * Note: this method is not thread-safe

 	 * @return A Config instance

 	 */

 	public static synchronized FileConfig getInstance()

 	{

 		if (instance == null) {

 			instance = new FileConfig();

 		}

 		return instance;

 	}

 	// Every config instance is initialized with the default values.

 	private final Properties settings = (Properties) defaultConfig.clone();

 	/**

 	 * Config is a singelton class with only one instance at time.

 	 * So the constructor is private to prevent the creation of more

 	 * then one Config instance.

 	 * @see Config.getInstance() to retrieve an instance of Config

 	 */

 	private FileConfig()

 	{

 		try {

 			// Load settings from file

 			load();

 		} catch (IOException ex) {

 			ex.printStackTrace();

 		}

 	}

 	/**

 	 * Loads the configuration from the config file. By default this is done

 	 * by the (private) constructor but it can be useful to reload the config

 	 * by invoking this method.

 	 * @throws IOException

 	 */

 	public void load()

 		throws IOException

 	{

 		FileInputStream in = null;

 		try {

 			in = new FileInputStream(

 				Config.inst().get(Config.LEVEL_CLI, Config.CONFIGFILE, "sonews.conf"));

 			settings.load(in);

 		} catch (FileNotFoundException e) {

 			// MUST NOT use Log otherwise endless loop

 			System.err.println(e.getMessage());

 			save();

 		} finally {

 			if (in != null) {

 				in.close();

 			}

 		}

 	}

 	/**

 	 * Saves this Config to the config file. By default this is done

 	 * at program end.

 	 * @throws FileNotFoundException

 	 * @throws IOException

 	 */

 	public void save() throws FileNotFoundException, IOException

 	{

 		FileOutputStream out = null;

 		try {

 			out = new FileOutputStream(

 				Config.inst().get(Config.LEVEL_CLI, Config.CONFIGFILE, "sonews.conf"));

 			settings.store(out, "SONEWS Config File");

 			out.flush();

 		} catch (IOException ex) {

 			throw ex;

 		} finally {

 			if (out != null) {

 				out.close();

 			}

 		}

 	}

 	/**

 	 * Returns the value that is stored within this config

 	 * identified by the given key. If the key cannot be found

 	 * the default value is returned.

 	 * @param key Key to identify the value.

 	 * @param def The default value that is returned if the key

 	 * is not found in this Config.

 	 * @return

 	 */

 	@Override

 	public String get(String key, String def)

 	{

 		return settings.getProperty(key, def);

 	}

 	/**

 	 * Sets the value for a given key.

 	 * @param key

 	 * @param value

 	 */

 	@Override

 	public void set(final String key, final String value)

 	{

 		settings.setProperty(key, value);

 	}

 }