/**

  * SQL-DK

  * Copyright © 2015 František Kučera (frantovo.cz)

  *

  * 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, version 3 of the License.

  *

  * 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 info.globalcode.sql.dk.configuration;

 import info.globalcode.sql.dk.*;

 import static info.globalcode.sql.dk.DatabaseConnection.JDBC_PROPERTY_USER;

 import static info.globalcode.sql.dk.DatabaseConnection.JDBC_PROPERTY_PASSWORD;

 import java.sql.Connection;

 import java.sql.Driver;

 import java.sql.DriverManager;

 import java.sql.SQLException;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import javax.xml.bind.JAXBContext;

 import javax.xml.bind.Unmarshaller;

 /**

  * Configuration loader – deserializes Configuration from the XML file.

  *

  * @author Ing. František Kučera (frantovo.cz)

  */

 public class Loader {

 	private static final Logger log = Logger.getLogger(Loader.class.getName());

 	public Configuration loadConfiguration() throws ConfigurationException {

 		try {

 			JAXBContext jaxb = JAXBContext.newInstance(Configuration.class.getPackage().getName(), Configuration.class.getClassLoader());

 			Unmarshaller u = jaxb.createUnmarshaller();

 			return (Configuration) u.unmarshal(Constants.CONFIG_FILE);

 		} catch (Exception e) {

 			throw new ConfigurationException("Unable to load configuration from " + Constants.CONFIG_FILE, e);

 		}

 	}

 	/**

 	 * JDBC connection should not be used directly in SQL-DK.

 	 *

 	 * @see DatabaseDefinition#connect(info.globalcode.sql.dk.configuration.Properties)

 	 * @param properties

 	 * @param databaseDefinition

 	 * @return

 	 * @throws java.sql.SQLException

 	 */

 	public static Connection jdbcConnect(DatabaseDefinition databaseDefinition, Properties properties) throws SQLException {

 		synchronized (properties) {

 			/**

 			 * Avoid rewriting the properties. Usually, the connection is created only once, but

 			 * with --test-connection and with SQL-DK JDBC driver, it might be reused.

 			 */

 			properties = properties.clone();

 		}

 		if (properties.hasProperty(JDBC_PROPERTY_PASSWORD)) {

 			log.log(Level.WARNING, "Passing DB password as CLI parameter is insecure!");

 		}

 		Properties credentials = new Properties();

 		credentials.add(new Property(JDBC_PROPERTY_USER, databaseDefinition.getUserName()));

 		credentials.add(new Property(JDBC_PROPERTY_PASSWORD, databaseDefinition.getPassword()));

 		credentials.setDefaults(databaseDefinition.getProperties());

 		properties.setDefaults(credentials);

 		java.util.Properties javaProperties = properties.getJavaProperties();

 		String driverClassName = databaseDefinition.getDriver();

 		final String url = databaseDefinition.getUrl();

 		if (driverClassName == null) {

 			log.log(Level.FINE, "Using DriverManager to create connection for „{0}“", url);

 			return DriverManager.getConnection(url, javaProperties);

 		} else {

 			log.log(Level.FINE, "Using custom Driver „{0}“ to create connection for „{1}“", new Object[]{driverClassName, url});

 			try {

 				Class<Driver> driverClass = (Class<Driver>) Class.forName(driverClassName);

 				Driver driver = driverClass.newInstance();

 				Connection connection = driver.connect(url, javaProperties);

 				if (connection == null) {

 					log.log(Level.SEVERE, "Driver „{0}“ returend null → it does not accept the URL: „{1}“", new Object[]{driverClassName, url});

 					throw new SQLException("Unable to connect: driver returned null.");

 				} else {

 					return connection;

 				}

 			} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | SQLException e) {

 				throw new SQLException("Unable to connect usig specific driver: " + driverClassName, e);

 			}

 		}

 	}

 }