/* ===========================================================
 * 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.]
 *
 * ------------------------------
 * GroupedStackedBarRenderer.java
 * ------------------------------
 * (C) Copyright 2004-present, by David Gilbert and Contributors.
 *
 * Original Author:  David Gilbert;
 * Contributor(s):   -;
 *
 */

package org.jfree.chart.renderer.category;

import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

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.ui.RectangleEdge;
import org.jfree.chart.util.Args;
import org.jfree.chart.util.PublicCloneable;
import org.jfree.data.KeyToGroupMap;
import org.jfree.data.Range;
import org.jfree.data.category.CategoryDataset;
import org.jfree.data.general.DatasetUtils;

/**
 * A renderer that draws stacked bars within groups.  This will probably be
 * merged with the {@link StackedBarRenderer} class at some point.  The example
 * shown here is generated by the {@code StackedBarChartDemo4.java}
 * program included in the JFreeChart Demo Collection:
 * <br><br>
 * <img src="doc-files/GroupedStackedBarRendererSample.png"
 * alt="GroupedStackedBarRendererSample.png">
 */
public class GroupedStackedBarRenderer extends StackedBarRenderer
        implements Cloneable, PublicCloneable, Serializable {

    /** For serialization. */
    private static final long serialVersionUID = -2725921399005922939L;

    /** A map used to assign each series to a group. */
    private KeyToGroupMap seriesToGroupMap;

    /**
     * Creates a new renderer.
     */
    public GroupedStackedBarRenderer() {
        super();
        this.seriesToGroupMap = new KeyToGroupMap();
    }

    /**
     * Updates the map used to assign each series to a group, and sends a
     * {@link RendererChangeEvent} to all registered listeners.
     *
     * @param map  the map ({@code null} not permitted).
     */
    public void setSeriesToGroupMap(KeyToGroupMap map) {
        Args.nullNotPermitted(map, "map");
        this.seriesToGroupMap = map;
        fireChangeEvent();
    }

    /**
     * Returns the range of values the renderer requires to display all the
     * items from the specified dataset.
     *
     * @param dataset  the dataset ({@code null} permitted).
     *
     * @return The range (or {@code null} if the dataset is
     *         {@code null} or empty).
     */
    @Override
    public Range findRangeBounds(CategoryDataset dataset) {
        if (dataset == null) {
            return null;
        }
        Range r = DatasetUtils.findStackedRangeBounds(
                dataset, this.seriesToGroupMap);
        return r;
    }

    /**
     * Calculates the bar width and stores it in the renderer state.  We
     * override the method in the base class to take account of the
     * series-to-group mapping.
     *
     * @param plot  the plot.
     * @param dataArea  the data area.
     * @param rendererIndex  the renderer index.
     * @param state  the renderer state.
     */
    @Override
    protected void calculateBarWidth(CategoryPlot plot, Rectangle2D dataArea,
            int rendererIndex, CategoryItemRendererState state) {

        // calculate the bar width
        CategoryAxis xAxis = plot.getDomainAxisForDataset(rendererIndex);
        CategoryDataset data = plot.getDataset(rendererIndex);
        if (data != null) {
            PlotOrientation orientation = plot.getOrientation();
            double space = 0.0;
            if (orientation == PlotOrientation.HORIZONTAL) {
                space = dataArea.getHeight();
            }
            else if (orientation == PlotOrientation.VERTICAL) {
                space = dataArea.getWidth();
            }
            double maxWidth = space * getMaximumBarWidth();
            int groups = this.seriesToGroupMap.getGroupCount();
            int categories = data.getColumnCount();
            int columns = groups * categories;
            double categoryMargin = 0.0;
            double itemMargin = 0.0;
            if (categories > 1) {
                categoryMargin = xAxis.getCategoryMargin();
            }
            if (groups > 1) {
                itemMargin = getItemMargin();
            }

            double used = space * (1 - xAxis.getLowerMargin()
                                     - xAxis.getUpperMargin()
                                     - categoryMargin - itemMargin);
            if (columns > 0) {
                state.setBarWidth(Math.min(used / columns, maxWidth));
            }
            else {
                state.setBarWidth(Math.min(used, maxWidth));
            }
        }

    }

    /**
     * Calculates the coordinate of the first "side" of a bar.  This will be
     * the minimum x-coordinate for a vertical bar, and the minimum
     * y-coordinate for a horizontal bar.
     *
     * @param plot  the plot.
     * @param orientation  the plot orientation.
     * @param dataArea  the data area.
     * @param domainAxis  the domain axis.
     * @param state  the renderer state (has the bar width precalculated).
     * @param row  the row index.
     * @param column  the column index.
     *
     * @return The coordinate.
     */
    @Override
    protected double calculateBarW0(CategoryPlot plot, 
            PlotOrientation orientation, Rectangle2D dataArea,
            CategoryAxis domainAxis, CategoryItemRendererState state,
            int row, int column) {
        // calculate bar width...
        double space;
        if (orientation == PlotOrientation.HORIZONTAL) {
            space = dataArea.getHeight();
        }
        else {
            space = dataArea.getWidth();
        }
        double barW0 = domainAxis.getCategoryStart(column, getColumnCount(),
                dataArea, plot.getDomainAxisEdge());
        int groupCount = this.seriesToGroupMap.getGroupCount();
        int groupIndex = this.seriesToGroupMap.getGroupIndex(
                this.seriesToGroupMap.getGroup(plot.getDataset(
                        plot.getIndexOf(this)).getRowKey(row)));
        int categoryCount = getColumnCount();
        if (groupCount > 1) {
            double groupGap = space * getItemMargin()
                              / (categoryCount * (groupCount - 1));
            double groupW = calculateSeriesWidth(space, domainAxis,
                    categoryCount, groupCount);
            barW0 = barW0 + groupIndex * (groupW + groupGap)
                          + (groupW / 2.0) - (state.getBarWidth() / 2.0);
        }
        else {
            barW0 = domainAxis.getCategoryMiddle(column, getColumnCount(),
                    dataArea, plot.getDomainAxisEdge())
                    - state.getBarWidth() / 2.0;
        }
        return barW0;
    }

    /**
     * Draws a stacked bar for a specific item.
     *
     * @param g2  the graphics device.
     * @param state  the renderer state.
     * @param dataArea  the plot area.
     * @param plot  the plot.
     * @param domainAxis  the domain (category) axis.
     * @param rangeAxis  the range (value) axis.
     * @param dataset  the data.
     * @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) {

        // nothing is drawn for null values...
        Number dataValue = dataset.getValue(row, column);
        if (dataValue == null) {
            return;
        }

        double value = dataValue.doubleValue();
        Comparable group = this.seriesToGroupMap.getGroup(
                dataset.getRowKey(row));
        PlotOrientation orientation = plot.getOrientation();
        double barW0 = calculateBarW0(plot, orientation, dataArea, domainAxis,
                state, row, column);

        double positiveBase = 0.0;
        double negativeBase = 0.0;

        for (int i = 0; i < row; i++) {
            if (group.equals(this.seriesToGroupMap.getGroup(
                    dataset.getRowKey(i)))) {
                Number v = dataset.getValue(i, column);
                if (v != null) {
                    double d = v.doubleValue();
                    if (d > 0) {
                        positiveBase = positiveBase + d;
                    }
                    else {
                        negativeBase = negativeBase + d;
                    }
                }
            }
        }

        double translatedBase;
        double translatedValue;
        boolean positive = (value > 0.0);
        boolean inverted = rangeAxis.isInverted();
        RectangleEdge barBase;
        if (orientation == PlotOrientation.HORIZONTAL) {
            if (positive && inverted || !positive && !inverted) {
                barBase = RectangleEdge.RIGHT;
            }
            else {
                barBase = RectangleEdge.LEFT;
            }
        }
        else {
            if (positive && !inverted || !positive && inverted) {
                barBase = RectangleEdge.BOTTOM;
            }
            else {
                barBase = RectangleEdge.TOP;
            }
        }
        RectangleEdge location = plot.getRangeAxisEdge();
        if (value > 0.0) {
            translatedBase = rangeAxis.valueToJava2D(positiveBase, dataArea,
                    location);
            translatedValue = rangeAxis.valueToJava2D(positiveBase + value,
                    dataArea, location);
        }
        else {
            translatedBase = rangeAxis.valueToJava2D(negativeBase, dataArea,
                    location);
            translatedValue = rangeAxis.valueToJava2D(negativeBase + value,
                    dataArea, location);
        }
        double barL0 = Math.min(translatedBase, translatedValue);
        double barLength = Math.max(Math.abs(translatedValue - translatedBase),
                getMinimumBarLength());

        Rectangle2D bar;
        if (orientation == PlotOrientation.HORIZONTAL) {
            bar = new Rectangle2D.Double(barL0, barW0, barLength,
                    state.getBarWidth());
        }
        else {
            bar = new Rectangle2D.Double(barW0, barL0, state.getBarWidth(),
                    barLength);
        }
        getBarPainter().paintBar(g2, this, row, column, bar, barBase);

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

        // collect entity and tool tip information...
        if (state.getInfo() != null) {
            EntityCollection entities = state.getEntityCollection();
            if (entities != null) {
                addItemEntity(entities, dataset, row, column, bar);
            }
        }

    }

    /**
     * Tests this renderer for equality with an arbitrary object.
     *
     * @param obj  the object ({@code null} permitted).
     *
     * @return A boolean.
     */
    @Override
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof GroupedStackedBarRenderer)) {
            return false;
        }
        GroupedStackedBarRenderer that = (GroupedStackedBarRenderer) obj;
        if (!this.seriesToGroupMap.equals(that.seriesToGroupMap)) {
            return false;
        }
        return super.equals(obj);
    }

}