/*
    *
    * The DbUnit Database Testing Framework
    * Copyright (C)2002-2004, DbUnit.org
    *
    * This library 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 2.1 of the License, or (at your option) any later version.
   *
   * This library 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 library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   *
   */
  package org.dbunit.database;
  
  import java.sql.SQLException;
  import java.util.List;
  
  import org.dbunit.database.QueryDataSet.TableEntry;
  import org.dbunit.dataset.DataSetException;
  import org.dbunit.dataset.ITable;
  import org.dbunit.dataset.ITableIterator;
  import org.dbunit.dataset.ITableMetaData;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Iterator used to iterate over a list of tables using a specific query for retrieving
   * data for every table.
   * 
   * @author Manuel Laflamme
   * @author gommma (gommma AT users.sourceforge.net)
   * @author Last changed by: $Author$
   * @version $Revision$ $Date$
   * @since 1.5.6 (Sep 15, 2003)
   */
  public class QueryTableIterator implements ITableIterator
  {
  
      /**
       * Logger for this class
       */
      private static final Logger logger = LoggerFactory.getLogger(QueryTableIterator.class);
  
      private final List _tableEntries;
      private final IDatabaseConnection _connection;
      private IResultSetTable _currentTable;
      private int _index = -1;
  
      /**
       * @param tableEntries list of {@link TableEntry} objects
       * @param connection The database connection needed to load data
       */
      public QueryTableIterator(List tableEntries, IDatabaseConnection connection)
      {
      	if (tableEntries == null) {
  			throw new NullPointerException(
  					"The parameter 'tableEntries' must not be null");
  		}
      	if (connection == null) {
  			throw new NullPointerException(
  					"The parameter 'connection' must not be null");
  		}
      	
          _tableEntries = tableEntries;
          _connection = connection;
          _currentTable = null;
      }
  
      ////////////////////////////////////////////////////////////////////////////
      // ITableIterator interface
  
      /**
       * {@inheritDoc}
       */
      public boolean next() throws DataSetException
      {
          logger.debug("next() - start");
  
          _index++;
  
          // Ensure previous table is closed
          if (_currentTable != null)
          {
              _currentTable.close();
              _currentTable = null;
          }
  
          return _index < _tableEntries.size();
      }
  
      public boolean nextWithoutClosing()
     {
         _index++;
         _currentTable = null;
 
         return _index < _tableEntries.size();
     }
 
     /**
      * {@inheritDoc}
      */
     public ITableMetaData getTableMetaData() throws DataSetException
     {
         logger.debug("getTableMetaData() - start");
 
         QueryDataSet.TableEntry entry = (QueryDataSet.TableEntry)_tableEntries.get(_index);
 
         // No query specified, use metadata from dataset
         if (entry.getQuery() == null)
         {
             try
             {
                 ITable table = _connection.createTable(entry.getTableName());
                 return table.getTableMetaData();
             }
             catch (SQLException e)
             {
                 throw new DataSetException(e);
             }
         }
         else
         {
             return getTable().getTableMetaData();
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public ITable getTable() throws DataSetException
     {
         logger.debug("getTable() - start");
 
         if (_currentTable == null)
         {
             try
             {
                 QueryDataSet.TableEntry entry = (QueryDataSet.TableEntry)_tableEntries.get(_index);
 
                 // No query specified, use table from dataset
                 if (entry.getQuery() == null)
                 {
                     _currentTable = (IResultSetTable)_connection.createTable(entry.getTableName());
                 }
                 else
                 {
                     DatabaseConfig config = _connection.getConfig();
                     IResultSetTableFactory factory = (IResultSetTableFactory)config.getProperty(
                             DatabaseConfig.PROPERTY_RESULTSET_TABLE_FACTORY);
 
                     _currentTable = factory.createTable(entry.getTableName(), entry.getQuery(), _connection);
                 }
             }
             catch (SQLException e)
             {
                 throw new DataSetException(e);
             }
         }
         return _currentTable;
     }
 }