/*!
 * 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.platform.plugin.action.chartbeans;

import org.pentaho.chart.IChartLinkGenerator;

import java.util.regex.Matcher;

/**
 * Provides a collection of callback methods used by the chart beans API which give the api user the ability link data
 * points in the chart URLs or javascript. When the user clicks on a bar, point, or pie slice the user will execute the
 * link or javascript provided by implementors of this interface
 * 
 * @author arodriguez
 */
public class ChartLinkGenerator implements IChartLinkGenerator {

  private String urlTemplate;

  /**
   * Constructs a chart link generator. There are three placeholders that can be used within the url template that will
   * be replaced with the value at a given data point on the chart. The placeholders are "{series}", "{domain}", and
   * "{range}". For example if the template is http://www.weather.com?postalCode={domain} then at run time the string
   * "{domain}" will be replaced the the domain value of each data point. Prefix all javascript function calls with
   * "javascript:" (Ex. javascript:alert('hello world')).
   */
  public ChartLinkGenerator( String urlTemplate ) {
    this.urlTemplate = urlTemplate;
  }

  public String generateLink( String seriesName, String domainName, Number rangeValue ) {
    seriesName = Matcher.quoteReplacement( seriesName );
    domainName = Matcher.quoteReplacement( domainName );

    // escape single quotes for javascript
    seriesName = resolveEscapeCharacters( seriesName );
    domainName = resolveEscapeCharacters( domainName );

    return urlTemplate
        .replaceAll( "\\{series\\}", seriesName == null ? "" : seriesName ).replaceAll( "\\{domain\\}",
        domainName == null ? "" : domainName ).replaceAll( "\\{range\\}", rangeValue == null ? "" : rangeValue.toString() ); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$ //$NON-NLS-5$ //$NON-NLS-6$
  }

  private String resolveEscapeCharacters( String s ) {
    if ( this.urlTemplate.startsWith( "javascript:" ) && s.indexOf( "'" ) >= 0 ) {
      s = s.replaceAll( "'", "\\\\\\\\'" );
    }
    return s;
  }

  public String generateLink( String seriesName, Number domainValue, Number rangeValue ) {
    // escape single quotes for javascript
    seriesName = resolveEscapeCharacters( seriesName );
    return urlTemplate
        .replaceAll( "\\{series\\}", seriesName == null ? "" : seriesName ).replaceAll( "\\{domain\\}",
        domainValue == null ? "" : domainValue.toString() ).replaceAll( "\\{range\\}", rangeValue == null ? "" : rangeValue.toString() ); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$ //$NON-NLS-5$ //$NON-NLS-6$
  }

}