/*
    * Licensed under the GPL License. You may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *   https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
    *
    * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
    * WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
    * PURPOSE.
   */
  package psiprobe.beans.accessors;
  
  import oracle.jdbc.pool.OracleConnectionCacheManager;
  import oracle.jdbc.pool.OracleDataSource;
  import psiprobe.UtilsBase;
  import psiprobe.model.DataSourceInfo;
  
  import java.util.Properties;
  
  /**
   * Accesses oracle.jdbc.pool.OracleDataSource.
   *
   * <p>
   * Oracle connection pool is quite different from any other available for Tomcat. Datasources are
   * run by static OracleConnectionCacheManager, whereby application context scope datasource would
   * have a named entry in OracleConnectionCacheManager.
   * </p>
   * 
   * <p>
   * Datasources do not have information about pool as such, therefore this accessor has to do quite
   * tedious job of verifying whether the datasource has a record in the cache manager or not. The
   * pool information is subsequently retrieved from the relevant cache manager entry.
   * </p>
   */
  public class OracleDatasourceAccessor implements DatasourceAccessor {
  
    @Override
    public DataSourceInfo getInfo(Object resource) throws Exception {
      DataSourceInfo dataSourceInfo = null;
  
      if (canMap(resource)) {
        OracleDataSource source = (OracleDataSource) resource;
        OracleConnectionCacheManager occm =
            OracleConnectionCacheManager.getConnectionCacheManagerInstance();
        Properties cacheProperties = source.getConnectionCacheProperties();
        String cacheName = source.getConnectionCacheName();
        cacheName = cacheName != null && occm.existsCache(cacheName) ? cacheName : null;
  
        if (cacheProperties != null) {
  
          dataSourceInfo = new DataSourceInfo();
          if (cacheName != null) {
            dataSourceInfo.setBusyConnections(occm.getNumberOfActiveConnections(cacheName));
            dataSourceInfo.setEstablishedConnections(occm.getNumberOfAvailableConnections(cacheName)
                + dataSourceInfo.getBusyConnections());
          } else {
            dataSourceInfo.setBusyConnections(0);
            dataSourceInfo.setEstablishedConnections(0);
          }
  
          dataSourceInfo.setMaxConnections(UtilsBase.toInt(cacheProperties.getProperty("MaxLimit"), -1));
          dataSourceInfo.setJdbcUrl(source.getURL());
          dataSourceInfo.setUsername(source.getUser());
          dataSourceInfo.setResettable(true);
          dataSourceInfo.setType("oracle-jdbc");
        }
      }
      return dataSourceInfo;
    }
  
    @Override
    public boolean reset(Object resource) throws Exception {
      if (canMap(resource)) {
        ((OracleDataSource) resource).close();
        return true;
      }
      return false;
    }
  
    @Override
    public boolean canMap(Object resource) {
      return "oracle.jdbc.pool.OracleDataSource".equals(resource.getClass().getName())
          && resource instanceof OracleDataSource;
    }
  }