/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2021, 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., 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.]
 *
 * ---------------------------
 * SimpleHistogramDataset.java
 * ---------------------------
 * (C) Copyright 2005-2021, by Object Refinery Limited and Contributors.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   Sergei Ivanov;
 *
 * Changes
 * -------
 * 10-Jan-2005 : Version 1 (DG);
 * 21-May-2007 : Added clearObservations() and removeAllBins() (SI);
 * 10-Jul-2007 : Added null argument check to constructor (DG);
 * 03-Jul-2013 : Use ParamChecks (DG);
 *
 */

package org.jfree.data.statistics;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import org.jfree.chart.util.ObjectUtils;
import org.jfree.chart.util.Args;
import org.jfree.chart.util.PublicCloneable;

import org.jfree.data.DomainOrder;
import org.jfree.data.general.DatasetChangeEvent;
import org.jfree.data.xy.AbstractIntervalXYDataset;
import org.jfree.data.xy.IntervalXYDataset;

/**
 * A dataset used for creating simple histograms with custom defined bins.
 *
 * @see HistogramDataset
 */
public class SimpleHistogramDataset extends AbstractIntervalXYDataset
        implements IntervalXYDataset, Cloneable, PublicCloneable,
            Serializable {

    /** For serialization. */
    private static final long serialVersionUID = 7997996479768018443L;

    /** The series key. */
    private Comparable key;

    /** The bins. */
    private List bins;

    /**
     * A flag that controls whether or not the bin count is divided by the
     * bin size.
     */
    private boolean adjustForBinSize;

    /**
     * Creates a new histogram dataset.  Note that the
     * {@code adjustForBinSize} flag defaults to {@code true}.
     *
     * @param key  the series key ({@code null} not permitted).
     */
    public SimpleHistogramDataset(Comparable key) {
        Args.nullNotPermitted(key, "key");
        this.key = key;
        this.bins = new ArrayList();
        this.adjustForBinSize = true;
    }

    /**
     * Returns a flag that controls whether or not the bin count is divided by
     * the bin size in the {@link #getXValue(int, int)} method.
     *
     * @return A boolean.
     *
     * @see #setAdjustForBinSize(boolean)
     */
    public boolean getAdjustForBinSize() {
        return this.adjustForBinSize;
    }

    /**
     * Sets the flag that controls whether or not the bin count is divided by
     * the bin size in the {@link #getYValue(int, int)} method, and sends a
     * {@link DatasetChangeEvent} to all registered listeners.
     *
     * @param adjust  the flag.
     *
     * @see #getAdjustForBinSize()
     */
    public void setAdjustForBinSize(boolean adjust) {
        this.adjustForBinSize = adjust;
        notifyListeners(new DatasetChangeEvent(this, this));
    }

    /**
     * Returns the number of series in the dataset (always 1 for this dataset).
     *
     * @return The series count.
     */
    @Override
    public int getSeriesCount() {
        return 1;
    }

    /**
     * Returns the key for a series.  Since this dataset only stores a single
     * series, the {@code series} argument is ignored.
     *
     * @param series  the series (zero-based index, ignored in this dataset).
     *
     * @return The key for the series.
     */
    @Override
    public Comparable getSeriesKey(int series) {
        return this.key;
    }

    /**
     * Returns the order of the domain (or X) values returned by the dataset.
     *
     * @return The order (never {@code null}).
     */
    @Override
    public DomainOrder getDomainOrder() {
        return DomainOrder.ASCENDING;
    }

    /**
     * Returns the number of items in a series.  Since this dataset only stores
     * a single series, the {@code series} argument is ignored.
     *
     * @param series  the series index (zero-based, ignored in this dataset).
     *
     * @return The item count.
     */
    @Override
    public int getItemCount(int series) {
        return this.bins.size();
    }

    /**
     * Adds a bin to the dataset.  An exception is thrown if the bin overlaps
     * with any existing bin in the dataset.
     *
     * @param bin  the bin ({@code null} not permitted).
     *
     * @see #removeAllBins()
     */
    public void addBin(SimpleHistogramBin bin) {
        // check that the new bin doesn't overlap with any existing bin
        Iterator iterator = this.bins.iterator();
        while (iterator.hasNext()) {
            SimpleHistogramBin existingBin
                    = (SimpleHistogramBin) iterator.next();
            if (bin.overlapsWith(existingBin)) {
                throw new RuntimeException("Overlapping bin");
            }
        }
        this.bins.add(bin);
        Collections.sort(this.bins);
    }

    /**
     * Adds an observation to the dataset (by incrementing the item count for
     * the appropriate bin).  A runtime exception is thrown if the value does
     * not fit into any bin.
     *
     * @param value  the value.
     */
    public void addObservation(double value) {
        addObservation(value, true);
    }

    /**
     * Adds an observation to the dataset (by incrementing the item count for
     * the appropriate bin).  A runtime exception is thrown if the value does
     * not fit into any bin.
     *
     * @param value  the value.
     * @param notify  send {@link DatasetChangeEvent} to listeners?
     */
    public void addObservation(double value, boolean notify) {
        boolean placed = false;
        Iterator iterator = this.bins.iterator();
        while (iterator.hasNext() && !placed) {
            SimpleHistogramBin bin = (SimpleHistogramBin) iterator.next();
            if (bin.accepts(value)) {
                bin.setItemCount(bin.getItemCount() + 1);
                placed = true;
            }
        }
        if (!placed) {
            throw new RuntimeException("No bin.");
        }
        if (notify) {
            notifyListeners(new DatasetChangeEvent(this, this));
        }
    }

    /**
     * Adds a set of values to the dataset and sends a
     * {@link DatasetChangeEvent} to all registered listeners.
     *
     * @param values  the values ({@code null} not permitted).
     *
     * @see #clearObservations()
     */
    public void addObservations(double[] values) {
        for (int i = 0; i < values.length; i++) {
            addObservation(values[i], false);
        }
        notifyListeners(new DatasetChangeEvent(this, this));
    }

    /**
     * Removes all current observation data and sends a
     * {@link DatasetChangeEvent} to all registered listeners.
     *
     * @see #addObservations(double[])
     * @see #removeAllBins()
     */
    public void clearObservations() {
        Iterator iterator = this.bins.iterator();
        while (iterator.hasNext()) {
            SimpleHistogramBin bin = (SimpleHistogramBin) iterator.next();
            bin.setItemCount(0);
        }
        notifyListeners(new DatasetChangeEvent(this, this));
    }

    /**
     * Removes all bins and sends a {@link DatasetChangeEvent} to all
     * registered listeners.
     *
     * @see #addBin(SimpleHistogramBin)
     */
    public void removeAllBins() {
        this.bins = new ArrayList();
        notifyListeners(new DatasetChangeEvent(this, this));
    }

    /**
     * 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 (never {@code null}).
     */
    @Override
    public Number getX(int series, int item) {
        return getXValue(series, item);
    }

    /**
     * Returns the x-value (as a double primitive) for an item within a series.
     *
     * @param series  the series index (zero-based).
     * @param item  the item index (zero-based).
     *
     * @return The x-value.
     */
    @Override
    public double getXValue(int series, int item) {
        SimpleHistogramBin bin = (SimpleHistogramBin) this.bins.get(item);
        return (bin.getLowerBound() + bin.getUpperBound()) / 2.0;
    }

    /**
     * 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}).
     */
    @Override
    public Number getY(int series, int item) {
        return getYValue(series, item);
    }

    /**
     * Returns the y-value (as a double primitive) for an item within a series.
     *
     * @param series  the series index (zero-based).
     * @param item  the item index (zero-based).
     *
     * @return The y-value.
     *
     * @see #getAdjustForBinSize()
     */
    @Override
    public double getYValue(int series, int item) {
        SimpleHistogramBin bin = (SimpleHistogramBin) this.bins.get(item);
        if (this.adjustForBinSize) {
            return bin.getItemCount()
                   / (bin.getUpperBound() - bin.getLowerBound());
        }
        else {
            return bin.getItemCount();
        }
    }

    /**
     * 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.
     */
    @Override
    public Number getStartX(int series, int item) {
        return getStartXValue(series, item);
    }

    /**
     * Returns the start x-value (as a double primitive) for an item within a
     * series.
     *
     * @param series  the series (zero-based index).
     * @param item  the item (zero-based index).
     *
     * @return The start x-value.
     */
    @Override
    public double getStartXValue(int series, int item) {
        SimpleHistogramBin bin = (SimpleHistogramBin) this.bins.get(item);
        return bin.getLowerBound();
    }

    /**
     * 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.
     */
    @Override
    public Number getEndX(int series, int item) {
        return getEndXValue(series, item);
    }

    /**
     * Returns the end x-value (as a double primitive) for an item within a
     * series.
     *
     * @param series  the series index (zero-based).
     * @param item  the item index (zero-based).
     *
     * @return The end x-value.
     */
    @Override
    public double getEndXValue(int series, int item) {
        SimpleHistogramBin bin = (SimpleHistogramBin) this.bins.get(item);
        return bin.getUpperBound();
    }

    /**
     * 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.
     */
    @Override
    public Number getStartY(int series, int item) {
        return getY(series, item);
    }

    /**
     * Returns the start y-value (as a double primitive) for an item within a
     * series.
     *
     * @param series  the series index (zero-based).
     * @param item  the item index (zero-based).
     *
     * @return The start y-value.
     */
    @Override
    public double getStartYValue(int series, int item) {
        return getYValue(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.
     */
    @Override
    public Number getEndY(int series, int item) {
        return getY(series, item);
    }

    /**
     * Returns the end y-value (as a double primitive) for an item within a
     * series.
     *
     * @param series  the series index (zero-based).
     * @param item  the item index (zero-based).
     *
     * @return The end y-value.
     */
    @Override
    public double getEndYValue(int series, int item) {
        return getYValue(series, item);
    }

    /**
     * Compares the dataset 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 SimpleHistogramDataset)) {
            return false;
        }
        SimpleHistogramDataset that = (SimpleHistogramDataset) obj;
        if (!this.key.equals(that.key)) {
            return false;
        }
        if (this.adjustForBinSize != that.adjustForBinSize) {
            return false;
        }
        if (!this.bins.equals(that.bins)) {
            return false;
        }
        return true;
    }

    /**
     * Returns a clone of the dataset.
     *
     * @return A clone.
     *
     * @throws CloneNotSupportedException not thrown by this class, but maybe
     *         by subclasses (if any).
     */
    @Override
    public Object clone() throws CloneNotSupportedException {
        SimpleHistogramDataset clone = (SimpleHistogramDataset) super.clone();
        clone.bins = (List) ObjectUtils.deepClone(this.bins);
        return clone;
    }

}