/*!
* 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.plugin.jfreereport.reportcharts;

import org.jfree.chart.labels.StandardCategoryItemLabelGenerator;
import org.jfree.data.category.CategoryDataset;

import java.text.NumberFormat;

/**
 * A standard label generator that can be used with a {@link org.jfree.chart.renderer.category.CategoryItemRenderer}.
 */
public class LogCategoryItemLabelGenerator extends StandardCategoryItemLabelGenerator {

  /**
   *
   */
  private static final long serialVersionUID = 1L;

  public LogCategoryItemLabelGenerator() {
    super( DEFAULT_LABEL_FORMAT_STRING, NumberFormat.getInstance() );
  }

  /**
   * Creates a new generator with the specified number formatter.
   *
   * @param labelFormat the label format string (<code>null</code> not permitted).
   * @param formatter   the number formatter (<code>null</code> not permitted).
   */
  public LogCategoryItemLabelGenerator( final String labelFormat ) {
    super( labelFormat, NumberFormat.getInstance() );
  }

  /**
   * Creates the array of items that can be passed to the {@link java.text.MessageFormat} class for creating labels.
   *
   * @param dataset the dataset (<code>null</code> not permitted).
   * @param row     the row index (zero-based).
   * @param column  the column index (zero-based).
   * @return The items (never <code>null</code>).
   */
  protected Object[] createItemArray( final CategoryDataset dataset, final int row, final int column ) {
    final Object[] objects = super.createItemArray( dataset, row, column );
    final Number value = dataset.getValue( row, column );
    objects[ 2 ] = formatValue( value );
    return objects;
  }

  public static String formatValue( final Number number ) {
    if ( number == null ) {
      return null;
    }

    final double rawValue = number.doubleValue();
    final double value = Math.abs( rawValue );

    if ( value < 1000.0 ) {
      return NumberFormat.getNumberInstance().format( rawValue );
    } else if ( value < 1000000.0 ) {
      return NumberFormat.getNumberInstance().format( rawValue / 1000.0 ) + "K";
    } else if ( value < 1000000000.0 ) {
      return NumberFormat.getNumberInstance().format( rawValue / 1000000.0 ) + "M";
    } else if ( value < 1000000000000.0 ) {
      return NumberFormat.getNumberInstance().format( rawValue / 1000000000.0 ) + "B";
    } else {
      return NumberFormat.getNumberInstance().format( rawValue / 1000000000000.0 ) + "T";
    }
  }
}