/* ===========================================================
 * 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.]
 *
 * -------------------
 * CategoryMarker.java
 * -------------------
 * (C) Copyright 2005-present, by David Gilbert.
 *
 * Original Author:  David Gilbert;
 * Contributor(s):   Nicolas Brodu;
 *                   Tracy Hiltbrand (equals/hashCode comply with EqualsVerifier);
 *
 */

package org.jfree.chart.plot;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Paint;
import java.awt.Stroke;
import java.io.Serializable;
import java.util.Objects;

import org.jfree.chart.event.MarkerChangeEvent;
import org.jfree.chart.ui.LengthAdjustmentType;
import org.jfree.chart.util.Args;

/**
 * A marker for a category.
 * <br><br>
 * Note that for serialization to work correctly, the category key must be an
 * instance of a serializable class.
 *
 * @see CategoryPlot#addDomainMarker(CategoryMarker)
 */
public class CategoryMarker extends Marker implements Cloneable, Serializable {

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

    /**
     * A hint that the marker should be drawn as a line rather than a region.
     */
    private boolean drawAsLine = false;

    /**
     * Creates a new category marker for the specified category.
     *
     * @param key  the category key.
     */
    public CategoryMarker(Comparable key) {
        this(key, Color.GRAY, new BasicStroke(1.0f));
    }

    /**
     * Creates a new category marker.
     *
     * @param key  the key.
     * @param paint  the paint ({@code null} not permitted).
     * @param stroke  the stroke ({@code null} not permitted).
     */
    public CategoryMarker(Comparable key, Paint paint, Stroke stroke) {
        this(key, paint, stroke, paint, stroke, 1.0f);
    }

    /**
     * Creates a new category marker.
     *
     * @param key  the key.
     * @param paint  the paint ({@code null} not permitted).
     * @param stroke  the stroke ({@code null} not permitted).
     * @param outlinePaint  the outline paint ({@code null} permitted).
     * @param outlineStroke  the outline stroke ({@code null} permitted).
     * @param alpha  the alpha transparency.
     */
    public CategoryMarker(Comparable key, Paint paint, Stroke stroke,
                          Paint outlinePaint, Stroke outlineStroke,
                          float alpha) {
        super(paint, stroke, outlinePaint, outlineStroke, alpha);
        this.key = key;
        setLabelOffsetType(LengthAdjustmentType.EXPAND);
    }

    /**
     * Returns the key.
     *
     * @return The key.
     */
    public Comparable getKey() {
        return this.key;
    }

    /**
     * Sets the key and sends a {@link MarkerChangeEvent} to all registered
     * listeners.
     *
     * @param key  the key ({@code null} not permitted).
     */
    public void setKey(Comparable key) {
        Args.nullNotPermitted(key, "key");
        this.key = key;
        notifyListeners(new MarkerChangeEvent(this));
    }

    /**
     * Returns the flag that controls whether the marker is drawn as a region
     * or a line.
     *
     * @return A line.
     */
    public boolean getDrawAsLine() {
        return this.drawAsLine;
    }

    /**
     * Sets the flag that controls whether the marker is drawn as a region or
     * as a line, and sends a {@link MarkerChangeEvent} to all registered
     * listeners.
     *
     * @param drawAsLine  the flag.
     */
    public void setDrawAsLine(boolean drawAsLine) {
        this.drawAsLine = drawAsLine;
        notifyListeners(new MarkerChangeEvent(this));
    }

    /**
     * Tests the marker for equality with an arbitrary object.
     *
     * @param obj  the object ({@code null} permitted).
     *
     * @return A boolean.
     */
    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (!(obj instanceof CategoryMarker)) {
            return false;
        }
        CategoryMarker that = (CategoryMarker) obj;
        if (!that.canEqual(this)) {
            return false;
        }
        if (!Objects.equals(this.key, that.key)) {
            return false;
        }
        if (this.drawAsLine != that.drawAsLine) {
            return false;
        }
        return super.equals(obj);
    }

    /**
     * Ensures symmetry between super/subclass implementations of equals. For
     * more detail, see http://jqno.nl/equalsverifier/manual/inheritance.
     *
     * @param other Object
     * 
     * @return true ONLY if the parameter is THIS class type
     */
    @Override
    public boolean canEqual(Object other) {
        // Solves Problem: equals not symmetric
        return (other instanceof CategoryMarker);
    }

    @Override
    public int hashCode() {
        int hash = super.hashCode(); // equals calls superclass, hashCode must also
        hash = 89 * hash + Objects.hashCode(this.key);
        hash = 89 * hash + (this.drawAsLine ? 1 : 0);
        return hash;
    }
}