/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-present, by David Gilbert 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
 * Other names may be trademarks of their respective owners.]
 *
 * -------------------------
 * WaterfallBarRenderer.java
 * -------------------------
 * (C) Copyright 2003-present, by David Gilbert and Contributors.
 *
 * Original Author:  Darshan Shah;
 * Contributor(s):   David Gilbert;
 *
 */

package org.jfree.chart.renderer.category;

import java.awt.Color;
import java.awt.GradientPaint;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Stroke;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

import org.jfree.chart.axis.CategoryAxis;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.entity.EntityCollection;
import org.jfree.chart.event.RendererChangeEvent;
import org.jfree.chart.labels.CategoryItemLabelGenerator;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.renderer.AbstractRenderer;
import org.jfree.chart.ui.GradientPaintTransformType;
import org.jfree.chart.ui.RectangleEdge;
import org.jfree.chart.ui.StandardGradientPaintTransformer;
import org.jfree.chart.util.PaintUtils;
import org.jfree.chart.util.Args;
import org.jfree.chart.util.SerialUtils;
import org.jfree.data.Range;
import org.jfree.data.category.CategoryDataset;

/**
 * A renderer that handles the drawing of waterfall bar charts, for use with
 * the {@link CategoryPlot} class.  Some quirks to note:
 * <ul>
 * <li>the value in the last category of the dataset should be (redundantly)
 *   specified as the sum of the items in the preceding categories - otherwise
 *   the final bar in the plot will be incorrectly plotted;</li>
 * <li>the bar colors are defined using special methods in this class - the
 *   inherited methods (for example,
 *   {@link AbstractRenderer#setSeriesPaint(int, Paint)}) are ignored;</li>
 * </ul>
 * The example shown here is generated by the
 * {@code WaterfallChartDemo1.java} program included in the JFreeChart
 * Demo Collection:
 * <br><br>
 * <img src="doc-files/WaterfallBarRendererSample.png"
 * alt="WaterfallBarRendererSample.png">
 */
public class WaterfallBarRenderer extends BarRenderer {

    /** For serialization. */
    private static final long serialVersionUID = -2482910643727230911L;

    /** The paint used to draw the first bar. */
    private transient Paint firstBarPaint;

    /** The paint used to draw the last bar. */
    private transient Paint lastBarPaint;

    /** The paint used to draw bars having positive values. */
    private transient Paint positiveBarPaint;

    /** The paint used to draw bars having negative values. */
    private transient Paint negativeBarPaint;

    /**
     * Constructs a new renderer with default values for the bar colors.
     */
    public WaterfallBarRenderer() {
        this(new GradientPaint(0.0f, 0.0f, new Color(0x22, 0x22, 0xFF),
                0.0f, 0.0f, new Color(0x66, 0x66, 0xFF)),
                new GradientPaint(0.0f, 0.0f, new Color(0x22, 0xFF, 0x22),
                0.0f, 0.0f, new Color(0x66, 0xFF, 0x66)),
                new GradientPaint(0.0f, 0.0f, new Color(0xFF, 0x22, 0x22),
                0.0f, 0.0f, new Color(0xFF, 0x66, 0x66)),
                new GradientPaint(0.0f, 0.0f, new Color(0xFF, 0xFF, 0x22),
                0.0f, 0.0f, new Color(0xFF, 0xFF, 0x66)));
    }

    /**
     * Constructs a new waterfall renderer.
     *
     * @param firstBarPaint  the color of the first bar ({@code null} not
     *                       permitted).
     * @param positiveBarPaint  the color for bars with positive values
     *                          ({@code null} not permitted).
     * @param negativeBarPaint  the color for bars with negative values
     *                          ({@code null} not permitted).
     * @param lastBarPaint  the color of the last bar ({@code null} not
     *                      permitted).
     */
    public WaterfallBarRenderer(Paint firstBarPaint, Paint positiveBarPaint,
            Paint negativeBarPaint, Paint lastBarPaint) {
        super();
        Args.nullNotPermitted(firstBarPaint, "firstBarPaint");
        Args.nullNotPermitted(positiveBarPaint, "positiveBarPaint");
        Args.nullNotPermitted(negativeBarPaint, "negativeBarPaint");
        Args.nullNotPermitted(lastBarPaint, "lastBarPaint");
        this.firstBarPaint = firstBarPaint;
        this.lastBarPaint = lastBarPaint;
        this.positiveBarPaint = positiveBarPaint;
        this.negativeBarPaint = negativeBarPaint;
        setGradientPaintTransformer(new StandardGradientPaintTransformer(
                GradientPaintTransformType.CENTER_VERTICAL));
        setMinimumBarLength(1.0);
    }

    /**
     * Returns the paint used to draw the first bar.
     *
     * @return The paint (never {@code null}).
     */
    public Paint getFirstBarPaint() {
        return this.firstBarPaint;
    }

    /**
     * Sets the paint that will be used to draw the first bar and sends a
     * {@link RendererChangeEvent} to all registered listeners.
     *
     * @param paint  the paint ({@code null} not permitted).
     */
    public void setFirstBarPaint(Paint paint) {
        Args.nullNotPermitted(paint, "paint");
        this.firstBarPaint = paint;
        fireChangeEvent();
    }

    /**
     * Returns the paint used to draw the last bar.
     *
     * @return The paint (never {@code null}).
     */
    public Paint getLastBarPaint() {
        return this.lastBarPaint;
    }

    /**
     * Sets the paint that will be used to draw the last bar and sends a
     * {@link RendererChangeEvent} to all registered listeners.
     *
     * @param paint  the paint ({@code null} not permitted).
     */
    public void setLastBarPaint(Paint paint) {
        Args.nullNotPermitted(paint, "paint");
        this.lastBarPaint = paint;
        fireChangeEvent();
    }

    /**
     * Returns the paint used to draw bars with positive values.
     *
     * @return The paint (never {@code null}).
     */
    public Paint getPositiveBarPaint() {
        return this.positiveBarPaint;
    }

    /**
     * Sets the paint that will be used to draw bars having positive values.
     *
     * @param paint  the paint ({@code null} not permitted).
     */
    public void setPositiveBarPaint(Paint paint) {
        Args.nullNotPermitted(paint, "paint");
        this.positiveBarPaint = paint;
        fireChangeEvent();
    }

    /**
     * Returns the paint used to draw bars with negative values.
     *
     * @return The paint (never {@code null}).
     */
    public Paint getNegativeBarPaint() {
        return this.negativeBarPaint;
    }

    /**
     * Sets the paint that will be used to draw bars having negative values,
     * and sends a {@link RendererChangeEvent} to all registered listeners.
     *
     * @param paint  the paint ({@code null} not permitted).
     */
    public void setNegativeBarPaint(Paint paint) {
        Args.nullNotPermitted(paint, "paint");
        this.negativeBarPaint = paint;
        fireChangeEvent();
    }

    /**
     * Returns the range of values the renderer requires to display all the
     * items from the specified dataset.
     *
     * @param dataset  the dataset ({@code null} not permitted).
     *
     * @return The range (or {@code null} if the dataset is empty).
     */
    @Override
    public Range findRangeBounds(CategoryDataset dataset) {
        if (dataset == null) {
            return null;
        }
        boolean allItemsNull = true; // we'll set this to false if there is at
                                     // least one non-null data item...
        double minimum = 0.0;
        double maximum = 0.0;
        int columnCount = dataset.getColumnCount();
        for (int row = 0; row < dataset.getRowCount(); row++) {
            double runningTotal = 0.0;
            for (int column = 0; column <= columnCount - 1; column++) {
                Number n = dataset.getValue(row, column);
                if (n != null) {
                    allItemsNull = false;
                    double value = n.doubleValue();
                    if (column == columnCount - 1) {
                        // treat the last column value as an absolute
                        runningTotal = value;
                    }
                    else {
                        runningTotal = runningTotal + value;
                    }
                    minimum = Math.min(minimum, runningTotal);
                    maximum = Math.max(maximum, runningTotal);
                }
            }

        }
        if (!allItemsNull) {
            return new Range(minimum, maximum);
        }
        else {
            return null;
        }

    }

    /**
     * Draws the bar for a single (series, category) data item.
     *
     * @param g2  the graphics device.
     * @param state  the renderer state.
     * @param dataArea  the data area.
     * @param plot  the plot.
     * @param domainAxis  the domain axis.
     * @param rangeAxis  the range axis.
     * @param dataset  the dataset.
     * @param row  the row index (zero-based).
     * @param column  the column index (zero-based).
     * @param pass  the pass index.
     */
    @Override
    public void drawItem(Graphics2D g2, CategoryItemRendererState state,
            Rectangle2D dataArea, CategoryPlot plot, CategoryAxis domainAxis,
            ValueAxis rangeAxis, CategoryDataset dataset, int row, int column,
            int pass) {

        double previous = state.getSeriesRunningTotal();
        if (column == dataset.getColumnCount() - 1) {
            previous = 0.0;
        }
        double current = 0.0;
        Number n = dataset.getValue(row, column);
        if (n != null) {
            current = previous + n.doubleValue();
        }
        state.setSeriesRunningTotal(current);

        int categoryCount = getColumnCount();
        PlotOrientation orientation = plot.getOrientation();

        double rectX = 0.0;
        double rectY = 0.0;

        RectangleEdge rangeAxisLocation = plot.getRangeAxisEdge();

        // Y0
        double j2dy0 = rangeAxis.valueToJava2D(previous, dataArea,
                rangeAxisLocation);

        // Y1
        double j2dy1 = rangeAxis.valueToJava2D(current, dataArea,
                rangeAxisLocation);

        double valDiff = current - previous;
        if (j2dy1 < j2dy0) {
            double temp = j2dy1;
            j2dy1 = j2dy0;
            j2dy0 = temp;
        }

        // BAR WIDTH
        double rectWidth = state.getBarWidth();

        // BAR HEIGHT
        double rectHeight = Math.max(getMinimumBarLength(),
                Math.abs(j2dy1 - j2dy0));

        Comparable seriesKey = dataset.getRowKey(row);
        Comparable categoryKey = dataset.getColumnKey(column);
        if (orientation == PlotOrientation.HORIZONTAL) {
            rectY = domainAxis.getCategorySeriesMiddle(categoryKey, seriesKey,
                    dataset, getItemMargin(), dataArea, RectangleEdge.LEFT);

            rectX = j2dy0;
            rectHeight = state.getBarWidth();
            rectY = rectY - rectHeight / 2.0;
            rectWidth = Math.max(getMinimumBarLength(),
                    Math.abs(j2dy1 - j2dy0));

        }
        else if (orientation == PlotOrientation.VERTICAL) {
            rectX = domainAxis.getCategorySeriesMiddle(categoryKey, seriesKey,
                    dataset, getItemMargin(), dataArea, RectangleEdge.TOP);
            rectX = rectX - rectWidth / 2.0;
            rectY = j2dy0;
        }
        Rectangle2D bar = new Rectangle2D.Double(rectX, rectY, rectWidth,
                rectHeight);
        Paint seriesPaint;
        if (column == 0) {
            seriesPaint = getFirstBarPaint();
        }
        else if (column == categoryCount - 1) {
            seriesPaint = getLastBarPaint();
        }
        else {
            if (valDiff >= 0.0) {
                seriesPaint = getPositiveBarPaint();
            } else {
                seriesPaint = getNegativeBarPaint();
            }
        }
        if (getGradientPaintTransformer() != null
                && seriesPaint instanceof GradientPaint) {
            GradientPaint gp = (GradientPaint) seriesPaint;
            seriesPaint = getGradientPaintTransformer().transform(gp, bar);
        }
        g2.setPaint(seriesPaint);
        g2.fill(bar);

        // draw the outline...
        if (isDrawBarOutline()
                && state.getBarWidth() > BAR_OUTLINE_WIDTH_THRESHOLD) {
            Stroke stroke = getItemOutlineStroke(row, column);
            Paint paint = getItemOutlinePaint(row, column);
            if (stroke != null && paint != null) {
                g2.setStroke(stroke);
                g2.setPaint(paint);
                g2.draw(bar);
            }
        }

        CategoryItemLabelGenerator generator
            = getItemLabelGenerator(row, column);
        if (generator != null && isItemLabelVisible(row, column)) {
            drawItemLabel(g2, dataset, row, column, plot, generator, bar,
                    (valDiff < 0.0));
        }

        // add an item entity, if this information is being collected
        EntityCollection entities = state.getEntityCollection();
        if (entities != null) {
            addItemEntity(entities, dataset, row, column, bar);
        }

    }

    /**
     * Tests an object for equality with this instance.
     *
     * @param obj  the object ({@code null} permitted).
     *
     * @return A boolean.
     */
    @Override
    public boolean equals(Object obj) {

        if (obj == this) {
            return true;
        }
        if (!super.equals(obj)) {
            return false;
        }
        if (!(obj instanceof WaterfallBarRenderer)) {
            return false;
        }
        WaterfallBarRenderer that = (WaterfallBarRenderer) obj;
        if (!PaintUtils.equal(this.firstBarPaint, that.firstBarPaint)) {
            return false;
        }
        if (!PaintUtils.equal(this.lastBarPaint, that.lastBarPaint)) {
            return false;
        }
        if (!PaintUtils.equal(this.positiveBarPaint,
                that.positiveBarPaint)) {
            return false;
        }
        if (!PaintUtils.equal(this.negativeBarPaint,
                that.negativeBarPaint)) {
            return false;
        }
        return true;

    }

    /**
     * Provides serialization support.
     *
     * @param stream  the output stream.
     *
     * @throws IOException  if there is an I/O error.
     */
    private void writeObject(ObjectOutputStream stream) throws IOException {
        stream.defaultWriteObject();
        SerialUtils.writePaint(this.firstBarPaint, stream);
        SerialUtils.writePaint(this.lastBarPaint, stream);
        SerialUtils.writePaint(this.positiveBarPaint, stream);
        SerialUtils.writePaint(this.negativeBarPaint, stream);
    }

    /**
     * Provides serialization support.
     *
     * @param stream  the input stream.
     *
     * @throws IOException  if there is an I/O error.
     * @throws ClassNotFoundException  if there is a classpath problem.
     */
    private void readObject(ObjectInputStream stream)
        throws IOException, ClassNotFoundException {
        stream.defaultReadObject();
        this.firstBarPaint = SerialUtils.readPaint(stream);
        this.lastBarPaint = SerialUtils.readPaint(stream);
        this.positiveBarPaint = SerialUtils.readPaint(stream);
        this.negativeBarPaint = SerialUtils.readPaint(stream);
    }

}