/* ===========================================================

 * JFreeChart : a free chart library for the Java(tm) platform

 * ===========================================================

 *

 * (C) Copyright 2000-2004, by Object Refinery Limited and Contributors.

 *

 * Project Info:  http://www.jfree.org/jfreechart/index.html

 *

 * 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.

 *

 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 

 * in the United States and other countries.]

 *

 * -----------------

 * XYBarDataset.java

 * -----------------

 * (C) Copyright 2004, by Object Refinery Limited and Contributors.

 *

 * Original Author:  David Gilbert (for Object Refinery Limited);

 * Contributor(s):   -;

 *

 * $Id: XYBarDataset.java,v 1.1 2004/08/31 15:36:12 mungady Exp $

 *

 * Changes

 * -------

 * 02-Mar-2004 : Version 1 (DG);

 * 05-May-2004 : Now extends AbstractIntervalXYDataset (DG);

 * 15-Jul-2004 : Switched getX() with getXValue() and getY() with getYValue() (DG);

 *

 */



package org.jfree.data.xy;



import org.jfree.data.general.DatasetChangeEvent;

import org.jfree.data.general.DatasetChangeListener;



/**

 * A dataset wrapper class that converts a standard {@link XYDataset} into an

 * {@link IntervalXYDataset} suitable for use in creating XY bar charts.

 */

public class XYBarDataset extends AbstractIntervalXYDataset

                          implements IntervalXYDataset, DatasetChangeListener {

    

    /** The underlying dataset. */

    private XYDataset underlying;

    

    /** The bar width. */

    private double barWidth;

    

    /**

     * Creates a new dataset.

     * 

     * @param underlying  the underlying dataset.

     * @param barWidth  the width of the bars.

     */

    public XYBarDataset(XYDataset underlying, double barWidth) {

        this.underlying = underlying;   

        this.underlying.addChangeListener(this);

        this.barWidth = barWidth;

    }



    /**

     * Returns the number of series in the dataset.

     *

     * @return The series count.

     */

    public int getSeriesCount() {

        return this.underlying.getSeriesCount();   

    }



    /**

     * Returns the name of a series.

     *

     * @param series  the series index (zero-based).

     *

     * @return The series name.

     */

    public String getSeriesName(int series) {

        return this.underlying.getSeriesName(series);   

    }

    

    /**

     * Returns the number of items in a series.

     *

     * @param series  the series index (zero-based).

     *

     * @return The item count.

     */

    public int getItemCount(int series) {

        return this.underlying.getItemCount(series);   

    }



    /**

     * Returns the x-value for an item within a series.  The x-values may or may not be returned

     * in ascending order, that is up to the class implementing the interface.

     *

     * @param series  the series index (zero-based).

     * @param item  the item index (zero-based).

     *

     * @return The x-value.

     */

    public Number getX(int series, int item) {

        return this.underlying.getX(series, item);   

    }



    /**

     * Returns the y-value for an item within a series.

     *

     * @param series  the series index (zero-based).

     * @param item  the item index (zero-based).

     *

     * @return The y-value (possibly <code>null</code>).

     */

    public Number getY(int series, int item) {

        return this.underlying.getY(series, item);   

    }



    /**

     * Returns the starting X value for the specified series and item.

     *

     * @param series  the series index (zero-based).

     * @param item  the item index (zero-based).

     *

     * @return The value.

     */

    public Number getStartX(int series, int item) {

        Number result = null;

        final Number xnum = this.underlying.getX(series, item);

        if (xnum != null) {

             result = new Double(xnum.doubleValue() - this.barWidth / 2.0);   

        }

        return result;   

    }



    /**

     * Returns the ending X value for the specified series and item.

     *

     * @param series  the series index (zero-based).

     * @param item  the item index (zero-based).

     *

     * @return The value.

     */

    public Number getEndX(int series, int item) {

        Number result = null;

        final Number xnum = this.underlying.getX(series, item);

        if (xnum != null) {

             result = new Double(xnum.doubleValue() + this.barWidth / 2.0);   

        }

        return result;   

    }



    /**

     * Returns the starting Y value for the specified series and item.

     *

     * @param series  the series index (zero-based).

     * @param item  the item index (zero-based).

     *

     * @return The value.

     */

    public Number getStartY(int series, int item) {

        return this.underlying.getY(series, item);   

    }



    /**

     * Returns the ending Y value for the specified series and item.

     *

     * @param series  the series index (zero-based).

     * @param item  the item index (zero-based).

     *

     * @return The value.

     */

    public Number getEndY(int series, int item) {

        return this.underlying.getY(series, item);   

    }



    /**

     * Receives notification of an dataset change event.

     *

     * @param event  information about the event.

     */

    public void datasetChanged(DatasetChangeEvent event) {

        this.notifyListeners(event);

    }



}

