/*
 * [ColorSaver.java]
 *
 * Summary: conserves RAM and time by reusing Color objects.
 *
 * Copyright: (c) 1998-2017 Roedy Green, Canadian Mind Products, http://mindprod.com
 *
 * Licence: This software may be copied and used freely for any purpose but military.
 *          http://mindprod.com/contact/nonmil.html
 *
 * Requires: JDK 1.8+
 *
 * Created with: JetBrains IntelliJ IDEA IDE http://www.jetbrains.com/idea/
 *
 * Version History:
 *  1.0 1998-01-16
 *  1.1 1998-11-10 new address and phone.
 *  1.2 2000-01-01
 *  1.3 2009-01-01 convert to JDK 1.5, split off from business package.
 */
package com.mindprod.colorsaver;

import java.awt.Color;
import java.util.HashMap;

@SuppressWarnings( { "ALL" } )
/**
 * conserves RAM and time by reusing Color objects.
 * <p/>
 * Instead of saying:
 * Color c = new Color(150,0,250);
 * say:
 * Color c = ColorSaver.create(150,0,250);
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 1.3 2009-01-01 convert to JDK 1.5, split off from business package.
 * @since 1998-01-16
 */
public class ColorSaver
    {
    private static final int FIRST_COPYRIGHT_YEAR = 1998;

    /**
     * undisplayed copyright notice
     */
    @SuppressWarnings( { "UnusedDeclaration" } )
    private static final String EMBEDDED_COPYRIGHT =
            "Copyright: (c) 1998-2017 Roedy Green, Canadian Mind Products, http://mindprod.com";

    private static final String RELEASE_DATE = "2009-01-01";

    private static final String VERSION_STRING = "1.3";

    /**
     * used to store previous Colors, indexed by Color
     */
    private static final HashMap<Color, Color> h = new HashMap<>( 51 /* init size */, .75f );

    static
        {
        // Load up the Hashtable with the color constant objects.
        // There is no need to create new copies of them.
        add( Color.BLACK );
        add( Color.WHITE );
        add( Color.LIGHT_GRAY );
        add( Color.GRAY );
        add( Color.DARK_GRAY );
        add( Color.BLACK );
        add( Color.RED );
        add( Color.PINK );
        add( Color.ORANGE );
        add( Color.YELLOW );
        add( Color.GREEN );
        add( Color.MAGENTA );
        add( Color.CYAN );
        add( Color.BLUE );
        }

    /**
     * add a Color to the cache, does not check if it is added already.
     *
     * @param color reference to a Color object.
     */
    private static void add( Color color )
        {
        h.put( color, color );
        }

    /**
     * returns Color object you give it if that colour has
     * not been used before, but gives you an old Color object
     * if it has.  The one you passed will be garbage collected.
     *
     * @param color new Color
     *
     * @return Color object, hopefully one created previously
     */
    public static Color create( Color color )
        {
        // see if we have used that Color before
        /* equals will find Color object with matching RGB. Need note be exact same Color object */
        Color prevColor = h.get( color );
        if ( prevColor != null )
            {
            return prevColor;
            }
        // we have not used that Color before.
        // Save a copy in case caller asks for it again.
        // The Hashtable will keep growing to keep all the colours used.
        add( color );
        return color;
        } // end create

    /**
     * create a new color
     *
     * @param r red 0..255
     * @param g green 0..255
     * @param b blue 0.255
     *
     * @return Color object, hopefully one created previously
     */
    public static Color create( int r, int g, int b )
        {
        return create( new Color( r, g, b ) );
        }

    /**
     * create a new color
     *
     * @param r red 0..1
     * @param g green 0..1
     * @param b blue 0.1
     *
     * @return Color object, hopefully one created previously
     */
    public static Color create( float r, float g, float b )
        {
        return create( new Color( r, g, b ) );
        }

    /**
     * create works just like the Color constructors:
     * create a new color
     *
     * @param rgb red 0..255,  green 0..255  blue 0.255, high bits 0.
     *
     * @return Color object, hopefully one created previously
     */
    public static Color create( int rgb )
        {
        return create( new Color( rgb ) );
        }
    } // end class ColorSaver