/*!
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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 Lesser General Public License for more details.
*
* Copyright (c) 2002-2013 Pentaho Corporation..  All rights reserved.
*/

package org.pentaho.reporting.engine.classic.extensions.datasources.kettle.parser;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.pentaho.reporting.engine.classic.core.modules.parser.base.PasswordEncryptionService;
import org.pentaho.reporting.engine.classic.extensions.datasources.kettle.FormulaArgument;
import org.pentaho.reporting.engine.classic.extensions.datasources.kettle.FormulaParameter;
import org.pentaho.reporting.engine.classic.extensions.datasources.kettle.KettleTransformationProducer;
import org.pentaho.reporting.libraries.xmlns.parser.AbstractXmlReadHandler;
import org.pentaho.reporting.libraries.xmlns.parser.ParseException;
import org.pentaho.reporting.libraries.xmlns.parser.XmlReadHandler;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;

import java.util.ArrayList;

public abstract class AbstractKettleTransformationProducerReadHandler
  extends AbstractXmlReadHandler implements KettleTransformationProducerReadHandler {
  private static final Log logger = LogFactory.getLog( AbstractKettleTransformationProducerReadHandler.class );

  private boolean stopOnError;
  private String name;
  private String stepName;
  private String username;
  private String password;
  private String repositoryName;
  private FormulaArgument[] definedArgumentNames;
  private FormulaParameter[] definedVariableNames;
  private ArrayList<ArgumentReadHandler> argumentHandlers;
  private ArrayList<VariableReadHandler> variablesHandlers;

  public AbstractKettleTransformationProducerReadHandler() {
    argumentHandlers = new ArrayList<ArgumentReadHandler>();
    variablesHandlers = new ArrayList<VariableReadHandler>();
  }

  public String getName() {
    return name;
  }

  /**
   * Starts parsing.
   *
   * @param attrs the attributes.
   * @throws SAXException if there is a parsing error.
   */
  protected void startParsing( final Attributes attrs ) throws SAXException {
    name = attrs.getValue( getUri(), "name" );
    if ( name == null ) {
      throw new ParseException( "Required attribute 'name' is not defined" );
    }

    repositoryName = attrs.getValue( getUri(), "repository" );
    if ( repositoryName == null ) {
      throw new ParseException( "Required attribute 'repository' is not defined" );
    }

    username = attrs.getValue( getUri(), "username" );
    password =
      PasswordEncryptionService.getInstance().decrypt( getRootHandler(), attrs.getValue( getUri(), "password" ) );

    stepName = attrs.getValue( getUri(), "step" );
    if ( stepName == null ) {
      logger.warn( "Required attribute 'step' is not defined. This query may not work correctly." );
    }

    // if undefined or invalid value, default to safe option of continuing, as this was the old behaviour,
    // and we dont want customers to have broken reports even though the KTRs they use are signaling errors.
    stopOnError = "true".equals( attrs.getValue( getUri(), "stop-on-error" ) );
  }

  /**
   * Returns the handler for a child element.
   *
   * @param uri     the URI of the namespace of the current element.
   * @param tagName the tag name.
   * @param atts    the attributes.
   * @return the handler or null, if the tagname is invalid.
   * @throws SAXException if there is a parsing error.
   */
  protected XmlReadHandler getHandlerForChild( final String uri, final String tagName, final Attributes atts )
    throws SAXException {
    if ( getUri().equals( uri ) == false ) {
      return null;
    }

    if ( "argument".equals( tagName ) ) {
      final ArgumentReadHandler readHandler = new ArgumentReadHandler();
      argumentHandlers.add( readHandler );
      return readHandler;
    }

    if ( "variable".equals( tagName ) ) {
      final VariableReadHandler readHandler = new VariableReadHandler();
      variablesHandlers.add( readHandler );
      return readHandler;
    }
    return null;
  }

  /**
   * Done parsing.
   *
   * @throws SAXException if there is a parsing error.
   */
  protected void doneParsing() throws SAXException {
    definedArgumentNames = new FormulaArgument[ argumentHandlers.size() ];
    for ( int i = 0; i < definedArgumentNames.length; i++ ) {
      final ArgumentReadHandler o = argumentHandlers.get( i );
      definedArgumentNames[ i ] = o.getFormula();
    }

    definedVariableNames = new FormulaParameter[ variablesHandlers.size() ];
    for ( int i = 0; i < definedVariableNames.length; i++ ) {
      final VariableReadHandler readHandler = variablesHandlers.get( i );
      definedVariableNames[ i ] = readHandler.getObject();
    }
  }

  public String getStepName() {
    return stepName;
  }

  public String getUsername() {
    return username;
  }

  public String getPassword() {
    return password;
  }

  public String getRepositoryName() {
    return repositoryName;
  }

  public FormulaArgument[] getDefinedArgumentNames() {
    return definedArgumentNames;
  }

  public FormulaParameter[] getDefinedVariableNames() {
    return definedVariableNames;
  }

  public boolean isStopOnError() {
    return stopOnError;
  }

  public final KettleTransformationProducer getTransformationProducer() throws SAXException {
    return getObject();
  }

  public abstract KettleTransformationProducer getObject() throws SAXException;
}