src/jexer/bits/Color.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2019 Kevin Lamonte
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  24  * DEALINGS IN THE SOFTWARE.
  25  *
  26  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  27  * @version 1
  28  */
  29 package jexer.bits;
  30
  31 /**
  32  * A text cell color.
  33  */
  34 public final class Color {
  35
  36     // ------------------------------------------------------------------------
  37     // Constants --------------------------------------------------------------
  38     // ------------------------------------------------------------------------
  39
  40     /**
  41      * SGR black value = 0.
  42      */
  43     private static final int SGRBLACK   = 0;
  44
  45     /**
  46      * SGR red value = 1.
  47      */
  48     private static final int SGRRED     = 1;
  49
  50     /**
  51      * SGR green value = 2.
  52      */
  53     private static final int SGRGREEN   = 2;
  54
  55     /**
  56      * SGR yellow value = 3.
  57      */
  58     private static final int SGRYELLOW  = 3;
  59
  60     /**
  61      * SGR blue value = 4.
  62      */
  63     private static final int SGRBLUE    = 4;
  64
  65     /**
  66      * SGR magenta value = 5.
  67      */
  68     private static final int SGRMAGENTA = 5;
  69
  70     /**
  71      * SGR cyan value = 6.
  72      */
  73     private static final int SGRCYAN    = 6;
  74
  75     /**
  76      * SGR white value = 7.
  77      */
  78     private static final int SGRWHITE   = 7;
  79
  80     /**
  81      * Black.  Bold + black = dark grey
  82      */
  83     public static final Color BLACK = new Color(SGRBLACK);
  84
  85     /**
  86      * Red.
  87      */
  88     public static final Color RED = new Color(SGRRED);
  89
  90     /**
  91      * Green.
  92      */
  93     public static final Color GREEN  = new Color(SGRGREEN);
  94
  95     /**
  96      * Yellow.  Sometimes not-bold yellow is brown.
  97      */
  98     public static final Color YELLOW = new Color(SGRYELLOW);
  99
 100     /**
 101      * Blue.
 102      */
 103     public static final Color BLUE = new Color(SGRBLUE);
 104
 105     /**
 106      * Magenta (purple).
 107      */
 108     public static final Color MAGENTA = new Color(SGRMAGENTA);
 109
 110     /**
 111      * Cyan (blue-green).
 112      */
 113     public static final Color CYAN = new Color(SGRCYAN);
 114
 115     /**
 116      * White.
 117      */
 118     public static final Color WHITE = new Color(SGRWHITE);
 119
 120     // ------------------------------------------------------------------------
 121     // Variables --------------------------------------------------------------
 122     // ------------------------------------------------------------------------
 123
 124     /**
 125      * The color value.  Default is SGRWHITE.
 126      */
 127     private int value = SGRWHITE;
 128
 129     // ------------------------------------------------------------------------
 130     // Constructors -----------------------------------------------------------
 131     // ------------------------------------------------------------------------
 132
 133     /**
 134      * Private constructor used to make the static Color instances.
 135      *
 136      * @param value the integer Color value
 137      */
 138     private Color(final int value) {
 139         this.value = value;
 140     }
 141
 142     // ------------------------------------------------------------------------
 143     // Color ------------------------------------------------------------------
 144     // ------------------------------------------------------------------------
 145
 146     /**
 147      * Get color value.  Note that these deliberately match the color values
 148      * of the ECMA-48 / ANSI X3.64 / VT100-ish SGR function ("ANSI colors").
 149      *
 150      * @return the value
 151      */
 152     public int getValue() {
 153         return value;
 154     }
 155
 156     /**
 157      * Public constructor returns one of the static Color instances.
 158      *
 159      * @param colorName "red", "blue", etc.
 160      * @return Color.RED, Color.BLUE, etc.
 161      */
 162     static Color getColor(final String colorName) {
 163         String str = colorName.toLowerCase();
 164
 165         if (str.equals("black")) {
 166             return Color.BLACK;
 167         } else if (str.equals("white")) {
 168             return Color.WHITE;
 169         } else if (str.equals("red")) {
 170             return Color.RED;
 171         } else if (str.equals("cyan")) {
 172             return Color.CYAN;
 173         } else if (str.equals("green")) {
 174             return Color.GREEN;
 175         } else if (str.equals("magenta")) {
 176             return Color.MAGENTA;
 177         } else if (str.equals("blue")) {
 178             return Color.BLUE;
 179         } else if (str.equals("yellow")) {
 180             return Color.YELLOW;
 181         } else if (str.equals("brown")) {
 182             return Color.YELLOW;
 183         } else {
 184             // Let unknown strings become white
 185             return Color.WHITE;
 186         }
 187     }
 188
 189     /**
 190      * Invert a color in the same way as (CGA/VGA color XOR 0x7).
 191      *
 192      * @return the inverted color
 193      */
 194     public Color invert() {
 195         switch (value) {
 196         case SGRBLACK:
 197             return Color.WHITE;
 198         case SGRWHITE:
 199             return Color.BLACK;
 200         case SGRRED:
 201             return Color.CYAN;
 202         case SGRCYAN:
 203             return Color.RED;
 204         case SGRGREEN:
 205             return Color.MAGENTA;
 206         case SGRMAGENTA:
 207             return Color.GREEN;
 208         case SGRBLUE:
 209             return Color.YELLOW;
 210         case SGRYELLOW:
 211             return Color.BLUE;
 212         default:
 213             throw new IllegalArgumentException("Invalid Color value: " + value);
 214         }
 215     }
 216
 217     /**
 218      * Comparison check.  All fields must match to return true.
 219      *
 220      * @param rhs another Color instance
 221      * @return true if all fields are equal
 222      */
 223     @Override
 224     public boolean equals(final Object rhs) {
 225         if (!(rhs instanceof Color)) {
 226             return false;
 227         }
 228
 229         Color that = (Color) rhs;
 230         return (value == that.value);
 231     }
 232
 233     /**
 234      * Hashcode uses all fields in equals().
 235      *
 236      * @return the hash
 237      */
 238     @Override
 239     public int hashCode() {
 240         return value;
 241     }
 242
 243     /**
 244      * Make human-readable description of this Color.
 245      *
 246      * @return displayable String "red", "blue", etc.
 247      */
 248     @Override
 249     public String toString() {
 250         switch (value) {
 251         case SGRBLACK:
 252             return "black";
 253         case SGRWHITE:
 254             return "white";
 255         case SGRRED:
 256             return "red";
 257         case SGRCYAN:
 258             return "cyan";
 259         case SGRGREEN:
 260             return "green";
 261         case SGRMAGENTA:
 262             return "magenta";
 263         case SGRBLUE:
 264             return "blue";
 265         case SGRYELLOW:
 266             return "yellow";
 267         default:
 268             throw new IllegalArgumentException("Invalid Color value: " + value);
 269         }
 270     }
 271
 272 }