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

 * 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.]

 *

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

 * StackedXYAreaRenderer2.java

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

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

 *

 * Original Author:  David Gilbert (for Object Refinery Limited), based on 

 *                   the StackedXYAreaRenderer class by Richard Atkinson;

 * Contributor(s):   -;

 *

 * $Id: StackedXYAreaRenderer2.java,v 1.2 2004/09/10 13:54:08 mungady Exp $

 *

 * Changes:

 * --------

 * 30-Apr-2004 : Version 1 (DG);

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

 * 10-Sep-2004 : Removed getRangeType() method (DG);

 * 

 */



package org.jfree.chart.renderer.xy;



import java.awt.Graphics2D;

import java.awt.Paint;

import java.awt.geom.GeneralPath;

import java.awt.geom.Rectangle2D;

import java.io.Serializable;



import org.jfree.chart.axis.ValueAxis;

import org.jfree.chart.labels.XYToolTipGenerator;

import org.jfree.chart.plot.CrosshairState;

import org.jfree.chart.plot.PlotRenderingInfo;

import org.jfree.chart.plot.XYPlot;

import org.jfree.chart.renderer.AbstractRenderer;

import org.jfree.chart.urls.XYURLGenerator;

import org.jfree.data.Range;

import org.jfree.data.xy.TableXYDataset;

import org.jfree.data.xy.XYDataset;

import org.jfree.ui.RectangleEdge;

import org.jfree.util.PublicCloneable;



/**

 * A stacked area renderer for the {@link XYPlot} class.

 */

public class StackedXYAreaRenderer2 extends XYAreaRenderer2 

                                    implements Cloneable, 

                                               PublicCloneable,

                                               Serializable {



    /**

     * Creates a new renderer.

     */

    public StackedXYAreaRenderer2() {

        this(null, null);

    }



    /**

     * Constructs a new renderer.

     *

     * @param labelGenerator  the tool tip generator to use.  <code>null</code> is none.

     * @param urlGenerator  the URL generator (null permitted).

     */

    public StackedXYAreaRenderer2(XYToolTipGenerator labelGenerator, 

                                  XYURLGenerator urlGenerator) {

        super(labelGenerator, urlGenerator);

    }



    /**

     * Returns the range of values the renderer requires to display all the items from the

     * specified dataset.

     * 

     * @param dataset  the dataset (<code>null</code> permitted).

     * 

     * @return The range (or <code>null</code> if the dataset is <code>null</code> or empty).

     */

    public Range getRangeExtent(XYDataset dataset) {

        double min = Double.POSITIVE_INFINITY;

        double max = Double.NEGATIVE_INFINITY;

        TableXYDataset d = (TableXYDataset) dataset;

        int itemCount = d.getItemCount();

        for (int i = 0; i < itemCount; i++) {

            double[] stackValues = getStackValues(dataset, d.getSeriesCount(), i);

            min = Math.min(min, stackValues[0]);

            max = Math.max(max, stackValues[1]);

        }

        return new Range(min, max);

    }



    /**

     * Returns the number of passes required by the renderer.

     * 

     * @return 1.

     */

    public int getPassCount() {

        return 1;

    }



    /**

     * Draws the visual representation of a single data item.

     *

     * @param g2  the graphics device.

     * @param state  the renderer state.

     * @param dataArea  the area within which the data is being drawn.

     * @param info  collects information about the drawing.

     * @param plot  the plot (can be used to obtain standard color information etc).

     * @param domainAxis  the domain axis.

     * @param rangeAxis  the range axis.

     * @param dataset  the dataset.

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

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

     * @param crosshairState  information about crosshairs on a plot.

     * @param pass  the pass index.

     */

    public void drawItem(Graphics2D g2,

                         XYItemRendererState state,

                         Rectangle2D dataArea,

                         PlotRenderingInfo info,

                         XYPlot plot,

                         ValueAxis domainAxis,

                         ValueAxis rangeAxis,

                         XYDataset dataset,

                         int series,

                         int item,

                         CrosshairState crosshairState,

                         int pass) {



        // get the data point...

        Number x1n = dataset.getX(series, item);

        Number y1n = dataset.getY(series, item);

        if (y1n == null) {

            y1n = AbstractRenderer.ZERO;

        }        

        double x1 = x1n.doubleValue();

        double y1 = y1n.doubleValue();

        double[] stack1 = getStackValues(dataset, series, item);

        

        // get the previous point and the next point so we can calculate a "hot spot"

        // for the area (used by the chart entity)...

        Number x0n = dataset.getX(series, Math.max(item - 1, 0));

        Number y0n = dataset.getY(series, Math.max(item - 1, 0));

        if (y0n == null) {

            y0n = AbstractRenderer.ZERO;

        }

        double x0 = x0n.doubleValue();

        double y0 = y0n.doubleValue();

        double[] stack0 = getStackValues(dataset, series, Math.max(item - 1, 0));

        

        int itemCount = dataset.getItemCount(series);

        Number x2n = dataset.getX(series, Math.min(item + 1, itemCount - 1));

        Number y2n = dataset.getY(series, Math.min(item + 1, itemCount - 1));

        if (y2n == null) {

            y2n = AbstractRenderer.ZERO;

        }

        double x2 = x2n.doubleValue();

        double y2 = y2n.doubleValue();

        double[] stack2 = getStackValues(dataset, series, Math.min(item + 1, itemCount - 1));



        double xleft = (x0 + x1) / 2.0;

        double xright = (x1 + x2) / 2.0;

        double[] stackLeft = averageStackValues(stack0, stack1);

        double[] stackRight = averageStackValues(stack1, stack2);

        double[] adjStackLeft = adjustedStackValues(stack0, stack1);

        double[] adjStackRight = adjustedStackValues(stack1, stack2);

        

        RectangleEdge edge0 = plot.getDomainAxisEdge();

        float transX1 = (float) domainAxis.valueToJava2D(x1, dataArea, edge0);

        float transXLeft = (float) domainAxis.valueToJava2D(xleft, dataArea, edge0);

        float transXRight = (float) domainAxis.valueToJava2D(xright, dataArea, edge0);

        

        RectangleEdge edge1 = plot.getRangeAxisEdge();

        

        GeneralPath left = new GeneralPath();

        GeneralPath right = new GeneralPath();

        if (y1 >= 0.0) {  // handle positive value

            float transY1 = (float) rangeAxis.valueToJava2D(y1 + stack1[1], dataArea, edge1);

            float transStack1 = (float) rangeAxis.valueToJava2D(stack1[1], dataArea, edge1);

            //float transStackLeft = (float) rangeAxis.valueToJava2D(stackLeft[1], dataArea, edge1);

            float transStackLeft = (float) rangeAxis.valueToJava2D(

                adjStackLeft[1], dataArea, edge1

            );

            

            // LEFT POLYGON

            if (y0 >= 0.0) {

                double yleft = (y0 + y1) / 2.0 + stackLeft[1];

                float transYLeft = (float) rangeAxis.valueToJava2D(yleft, dataArea, edge1);

                left.moveTo(transX1, transY1);

                left.lineTo(transX1, transStack1);

                left.lineTo(transXLeft, transStackLeft);

                left.lineTo(transXLeft, transYLeft);

                left.closePath();

            }

            else {

                left.moveTo(transX1, transStack1);

                left.lineTo(transX1, transY1);

                left.lineTo(transXLeft, transStackLeft);

                left.closePath();

            }



            float transStackRight = (float) rangeAxis.valueToJava2D(

                adjStackRight[1], dataArea, edge1

            );

            // RIGHT POLYGON

            if (y2 >= 0.0) {

                double yright = (y1 + y2) / 2.0 + stackRight[1];

                float transYRight = (float) rangeAxis.valueToJava2D(yright, dataArea, edge1);

                right.moveTo(transX1, transStack1);

                right.lineTo(transX1, transY1);

                right.lineTo(transXRight, transYRight);

                right.lineTo(transXRight, transStackRight);

                right.closePath();

            }

            else {

                right.moveTo(transX1, transStack1);

                right.lineTo(transX1, transY1);

                right.lineTo(transXRight, transStackRight);

                right.closePath();

            }

        }

        else {  // handle negative value 

            float transY1 = (float) rangeAxis.valueToJava2D(y1 + stack1[0], dataArea, edge1);

            float transStack1 = (float) rangeAxis.valueToJava2D(stack1[0], dataArea, edge1);

            float transStackLeft = (float) rangeAxis.valueToJava2D(

                adjStackLeft[0], dataArea, edge1

            );



            // LEFT POLYGON

            if (y0 >= 0.0) {

                left.moveTo(transX1, transStack1);

                left.lineTo(transX1, transY1);

                left.lineTo(transXLeft, transStackLeft);

                left.clone();

            }

            else {

                double yleft = (y0 + y1) / 2.0 + stackLeft[0];

                float transYLeft = (float) rangeAxis.valueToJava2D(yleft, dataArea, edge1);

                left.moveTo(transX1, transY1);

                left.lineTo(transX1, transStack1);

                left.lineTo(transXLeft, transStackLeft);

                left.lineTo(transXLeft, transYLeft);

                left.closePath();

            }

            float transStackRight = (float) rangeAxis.valueToJava2D(

                adjStackRight[0], dataArea, edge1

            );

            

            // RIGHT POLYGON

            if (y2 >= 0.0) {

                right.moveTo(transX1, transStack1);

                right.lineTo(transX1, transY1);

                right.lineTo(transXRight, transStackRight);

                right.closePath();

            }

            else {

                double yright = (y1 + y2) / 2.0 + stackRight[0];

                float transYRight = (float) rangeAxis.valueToJava2D(yright, dataArea, edge1);

                right.moveTo(transX1, transStack1);

                right.lineTo(transX1, transY1);

                right.lineTo(transXRight, transYRight);

                right.lineTo(transXRight, transStackRight);

                right.closePath();

            }

        }



        //  Get series Paint and Stroke

        Paint itemPaint = getItemPaint(series, item);



        if (pass == 0) {



            g2.setPaint(itemPaint);

            g2.fill(left);

            g2.fill(right);



        } 



    }



    /**

     * Calculates the stacked value of the all series up to, but not including <code>series</code>

     * for the specified category, <code>category</code>.  It returns 0.0 if <code>series</code>

     * is the first series, i.e. 0.

     *

     * @param dataset  the data.

     * @param series  the series.

     * @param index  the index.

     *

     * @return double returns a cumulative value for all series' values up to

     * but excluding <code>series</code> for <code>index</code>.

     */

    private double[] getStackValues(XYDataset dataset, int series, int index) {

        double[] result = new double[2];

        for (int i = 0; i < series; i++) {

            Number n = dataset.getY(i, index);

            if (n != null) {

                double v = n.doubleValue();

                if (v >= 0.0) {

                    result[1] += v;   

                }

                else {

                    result[0] += v;   

                }

            }

        }

        return result;

    }

    

    /**

     * Returns a pair of "stack" values calculated from the two specified pairs.

     * 

     * @param stack1  the first stack pair.

     * @param stack2  the second stack pair.

     * 

     * @return A pair of average stack values.

     */

    private double[] averageStackValues(double[] stack1, double[] stack2) {

        double[] result = new double[2];

        result[0] = (stack1[0] + stack2[0]) / 2.0;

        result[1] = (stack1[1] + stack2[1]) / 2.0;

        return result;

    }



    /**

     * Returns a pair of "stack" values calculated from the two specified pairs.

     * 

     * @param stack1  the first stack pair.

     * @param stack2  the second stack pair.

     * 

     * @return A pair of average stack values.

     */

    private double[] adjustedStackValues(double[] stack1, double[] stack2) {

        double[] result = new double[2];

        if (stack1[0] == 0.0 || stack2[0] == 0.0) {

            result[0] = 0.0;   

        }

        else {

            result[0] = (stack1[0] + stack2[0]) / 2.0;

        }

        if (stack1[1] == 0.0 || stack2[1] == 0.0) {

            result[1] = 0.0;   

        }

        else {

            result[1] = (stack1[1] + stack2[1]) / 2.0;

        }

        return result;

    }



    /**

     * Returns a clone of the renderer.

     *

     * @return A clone.

     *

     * @throws CloneNotSupportedException  if the renderer cannot be cloned.

     */

    public Object clone() throws CloneNotSupportedException {

        return super.clone();

    }



}

