/*
 * SonarQube, open source software quality management tool.
 * Copyright (C) 2008-2013 SonarSource
 * mailto:contact AT sonarsource DOT com
 *
 * SonarQube is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * SonarQube 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package org.sonar.server.db;

import com.google.common.annotations.VisibleForTesting;
import org.apache.commons.lang.StringUtils;
import org.h2.Driver;
import org.h2.tools.Server;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.sonar.api.CoreProperties;
import org.sonar.api.config.Settings;
import org.sonar.api.database.DatabaseProperties;
import org.sonar.api.utils.SonarException;

import java.io.File;
import java.sql.DriverManager;
import java.sql.SQLException;

public class EmbeddedDatabase {
  private static final Logger LOG = LoggerFactory.getLogger(EmbeddedDatabase.class);
  private final Settings settings;
  private Server server;

  public EmbeddedDatabase(Settings settings) {
    this.settings = settings;
  }

  public void start() {
    File dbHome = getDataDirectory(settings);
    if (!dbHome.exists()) {
      dbHome.mkdirs();
    }

    String port = getSetting(DatabaseProperties.PROP_EMBEDDED_PORT, DatabaseProperties.PROP_EMBEDDED_PORT_DEFAULT_VALUE);
    String user = getSetting(DatabaseProperties.PROP_USER, DatabaseProperties.PROP_USER_DEFAULT_VALUE);
    String password = getSetting(DatabaseProperties.PROP_PASSWORD, DatabaseProperties.PROP_PASSWORD_DEFAULT_VALUE);
    String url = getSetting(DatabaseProperties.PROP_URL, DatabaseProperties.PROP_USER_DEFAULT_VALUE);

    try {
      if (url.contains("/mem:")) {
        server = Server.createTcpServer("-tcpPort", port, "-tcpAllowOthers", "-baseDir", dbHome.getAbsolutePath());
      } else {
        createDatabase(dbHome, user, password);
        server = Server.createTcpServer("-tcpPort", port, "-tcpAllowOthers", "-ifExists", "-baseDir", dbHome.getAbsolutePath());
      }

      LOG.info("Starting embedded database on port " + server.getPort() + " with url " + url);
      server.start();

      LOG.info("Embedded database started. Data stored in: " + dbHome.getAbsolutePath());
    } catch (Exception e) {
      throw new SonarException("Unable to start database", e);
    }
  }

  public void stop() {
    if (server != null) {
      server.stop();
      server = null;
      LOG.info("Embedded database stopped");
    }
  }

  @VisibleForTesting
  File getDataDirectory(Settings settings) {
    String dirName = settings.getString(DatabaseProperties.PROP_EMBEDDED_DATA_DIR);
    if (!StringUtils.isBlank(dirName)) {
      return getEmbeddedDataDirectory(dirName);
    }
    return getSonarHomeDataDirectory(settings);
  }

  private File getEmbeddedDataDirectory(String directoryName) {
    File embeddedDataDirectory = new File(directoryName);
    if(embeddedDataDirectory.exists() && !embeddedDataDirectory.isDirectory()) {
      throw new SonarException("Database home " + embeddedDataDirectory.getAbsolutePath() + " is not a directory");
    }
    return embeddedDataDirectory;
  }

  private File getSonarHomeDataDirectory(Settings settings) {
    File sonarHome = new File(settings.getString(CoreProperties.SONAR_HOME));
    if (!sonarHome.isDirectory()) {
      throw new IllegalStateException("SonarQube home directory is not valid");
    }
    return new File(sonarHome, "data");
  }

  private String getSetting(String name, String defaultValue) {
    return StringUtils.defaultIfBlank(settings.getString(name), defaultValue);
  }

  private void createDatabase(File dbHome, String user, String password) throws SQLException {
    String url = String.format("jdbc:h2:%s/sonar;USER=%s;PASSWORD=%s", dbHome.getAbsolutePath(), user, password);

    DriverManager.registerDriver(new Driver());
    DriverManager.getConnection(url).close();
  }
}