src/jexer/io/ECMA48Screen.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2017 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.io;
  30
  31 import jexer.bits.Cell;
  32 import jexer.bits.CellAttributes;
  33
  34 /**
  35  * This Screen implementation draws to an xterm/ANSI X3.64/ECMA-48 type
  36  * terminal.
  37  */
  38 public final class ECMA48Screen extends Screen {
  39
  40     /**
  41      * Emit debugging to stderr.
  42      */
  43     private boolean debugToStderr = false;
  44
  45     /**
  46      * We call terminal.cursor() so need the instance.
  47      */
  48     private ECMA48Terminal terminal;
  49
  50     /**
  51      * Public constructor.
  52      *
  53      * @param terminal ECMA48Terminal to use
  54      */
  55     public ECMA48Screen(final ECMA48Terminal terminal) {
  56         this.terminal = terminal;
  57
  58         // Query the screen size
  59         setDimensions(terminal.getSessionInfo().getWindowWidth(),
  60             terminal.getSessionInfo().getWindowHeight());
  61     }
  62
  63     /**
  64      * Perform a somewhat-optimal rendering of a line.
  65      *
  66      * @param y row coordinate.  0 is the top-most row.
  67      * @param sb StringBuilder to write escape sequences to
  68      * @param lastAttr cell attributes from the last call to flushLine
  69      */
  70     private void flushLine(final int y, final StringBuilder sb,
  71         CellAttributes lastAttr) {
  72
  73         int lastX = -1;
  74         int textEnd = 0;
  75         for (int x = 0; x < width; x++) {
  76             Cell lCell = logical[x][y];
  77             if (!lCell.isBlank()) {
  78                 textEnd = x;
  79             }
  80         }
  81         // Push textEnd to first column beyond the text area
  82         textEnd++;
  83
  84         // DEBUG
  85         // reallyCleared = true;
  86
  87         for (int x = 0; x < width; x++) {
  88             Cell lCell = logical[x][y];
  89             Cell pCell = physical[x][y];
  90
  91             if (!lCell.equals(pCell) || reallyCleared) {
  92
  93                 if (debugToStderr) {
  94                     System.err.printf("\n--\n");
  95                     System.err.printf(" Y: %d X: %d\n", y, x);
  96                     System.err.printf("   lCell: %s\n", lCell);
  97                     System.err.printf("   pCell: %s\n", pCell);
  98                     System.err.printf("    ====    \n");
  99                 }
 100
 101                 if (lastAttr == null) {
 102                     lastAttr = new CellAttributes();
 103                     sb.append(terminal.normal());
 104                 }
 105
 106                 // Place the cell
 107                 if ((lastX != (x - 1)) || (lastX == -1)) {
 108                     // Advancing at least one cell, or the first gotoXY
 109                     sb.append(terminal.gotoXY(x, y));
 110                 }
 111
 112                 assert (lastAttr != null);
 113
 114                 if ((x == textEnd) && (textEnd < width - 1)) {
 115                     assert (lCell.isBlank());
 116
 117                     for (int i = x; i < width; i++) {
 118                         assert (logical[i][y].isBlank());
 119                         // Physical is always updated
 120                         physical[i][y].reset();
 121                     }
 122
 123                     // Clear remaining line
 124                     sb.append(terminal.clearRemainingLine());
 125                     lastAttr.reset();
 126                     return;
 127                 }
 128
 129                 // Now emit only the modified attributes
 130                 if ((lCell.getForeColor() != lastAttr.getForeColor())
 131                     && (lCell.getBackColor() != lastAttr.getBackColor())
 132                     && (lCell.isBold() == lastAttr.isBold())
 133                     && (lCell.isReverse() == lastAttr.isReverse())
 134                     && (lCell.isUnderline() == lastAttr.isUnderline())
 135                     && (lCell.isBlink() == lastAttr.isBlink())
 136                 ) {
 137                     // Both colors changed, attributes the same
 138                     sb.append(terminal.color(lCell.isBold(),
 139                             lCell.getForeColor(), lCell.getBackColor()));
 140
 141                     if (debugToStderr) {
 142                         System.err.printf("1 Change only fore/back colors\n");
 143                     }
 144                 } else if ((lCell.getForeColor() != lastAttr.getForeColor())
 145                     && (lCell.getBackColor() != lastAttr.getBackColor())
 146                     && (lCell.isBold() != lastAttr.isBold())
 147                     && (lCell.isReverse() != lastAttr.isReverse())
 148                     && (lCell.isUnderline() != lastAttr.isUnderline())
 149                     && (lCell.isBlink() != lastAttr.isBlink())
 150                 ) {
 151                     // Everything is different
 152                     sb.append(terminal.color(lCell.getForeColor(),
 153                             lCell.getBackColor(),
 154                             lCell.isBold(), lCell.isReverse(),
 155                             lCell.isBlink(),
 156                             lCell.isUnderline()));
 157
 158                     if (debugToStderr) {
 159                         System.err.printf("2 Set all attributes\n");
 160                     }
 161                 } else if ((lCell.getForeColor() != lastAttr.getForeColor())
 162                     && (lCell.getBackColor() == lastAttr.getBackColor())
 163                     && (lCell.isBold() == lastAttr.isBold())
 164                     && (lCell.isReverse() == lastAttr.isReverse())
 165                     && (lCell.isUnderline() == lastAttr.isUnderline())
 166                     && (lCell.isBlink() == lastAttr.isBlink())
 167                 ) {
 168
 169                     // Attributes same, foreColor different
 170                     sb.append(terminal.color(lCell.isBold(),
 171                             lCell.getForeColor(), true));
 172
 173                     if (debugToStderr) {
 174                         System.err.printf("3 Change foreColor\n");
 175                     }
 176                 } else if ((lCell.getForeColor() == lastAttr.getForeColor())
 177                     && (lCell.getBackColor() != lastAttr.getBackColor())
 178                     && (lCell.isBold() == lastAttr.isBold())
 179                     && (lCell.isReverse() == lastAttr.isReverse())
 180                     && (lCell.isUnderline() == lastAttr.isUnderline())
 181                     && (lCell.isBlink() == lastAttr.isBlink())
 182                 ) {
 183                     // Attributes same, backColor different
 184                     sb.append(terminal.color(lCell.isBold(),
 185                             lCell.getBackColor(), false));
 186
 187                     if (debugToStderr) {
 188                         System.err.printf("4 Change backColor\n");
 189                     }
 190                 } else if ((lCell.getForeColor() == lastAttr.getForeColor())
 191                     && (lCell.getBackColor() == lastAttr.getBackColor())
 192                     && (lCell.isBold() == lastAttr.isBold())
 193                     && (lCell.isReverse() == lastAttr.isReverse())
 194                     && (lCell.isUnderline() == lastAttr.isUnderline())
 195                     && (lCell.isBlink() == lastAttr.isBlink())
 196                 ) {
 197
 198                     // All attributes the same, just print the char
 199                     // NOP
 200
 201                     if (debugToStderr) {
 202                         System.err.printf("5 Only emit character\n");
 203                     }
 204                 } else {
 205                     // Just reset everything again
 206                     sb.append(terminal.color(lCell.getForeColor(),
 207                             lCell.getBackColor(),
 208                             lCell.isBold(),
 209                             lCell.isReverse(),
 210                             lCell.isBlink(),
 211                             lCell.isUnderline()));
 212
 213                     if (debugToStderr) {
 214                         System.err.printf("6 Change all attributes\n");
 215                     }
 216                 }
 217                 // Emit the character
 218                 sb.append(lCell.getChar());
 219
 220                 // Save the last rendered cell
 221                 lastX = x;
 222                 lastAttr.setTo(lCell);
 223
 224                 // Physical is always updated
 225                 physical[x][y].setTo(lCell);
 226
 227             } // if (!lCell.equals(pCell) || (reallyCleared == true))
 228
 229         } // for (int x = 0; x < width; x++)
 230     }
 231
 232     /**
 233      * Render the screen to a string that can be emitted to something that
 234      * knows how to process ECMA-48/ANSI X3.64 escape sequences.
 235      *
 236      * @return escape sequences string that provides the updates to the
 237      * physical screen
 238      */
 239     private String flushString() {
 240         if (!dirty) {
 241             assert (!reallyCleared);
 242             return "";
 243         }
 244
 245         CellAttributes attr = null;
 246
 247         StringBuilder sb = new StringBuilder();
 248         if (reallyCleared) {
 249             attr = new CellAttributes();
 250             sb.append(terminal.clearAll());
 251         }
 252
 253         for (int y = 0; y < height; y++) {
 254             flushLine(y, sb, attr);
 255         }
 256
 257         dirty = false;
 258         reallyCleared = false;
 259
 260         String result = sb.toString();
 261         if (debugToStderr) {
 262             System.err.printf("flushString(): %s\n", result);
 263         }
 264         return result;
 265     }
 266
 267     /**
 268      * Push the logical screen to the physical device.
 269      */
 270     @Override
 271     public void flushPhysical() {
 272         String result = flushString();
 273         if ((cursorVisible)
 274             && (cursorY <= height - 1)
 275             && (cursorX <= width - 1)
 276         ) {
 277             result += terminal.cursor(true);
 278             result += terminal.gotoXY(cursorX, cursorY);
 279         } else {
 280             result += terminal.cursor(false);
 281         }
 282         terminal.getOutput().write(result);
 283         terminal.flush();
 284     }
 285
 286     /**
 287      * Set the window title.
 288      *
 289      * @param title the new title
 290      */
 291     public void setTitle(final String title) {
 292         terminal.getOutput().write(terminal.setTitle(title));
 293         terminal.flush();
 294     }
 295
 296 }