| 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.teditor; |
| 30 | |
| 31 | import java.util.ArrayList; |
| 32 | import java.util.List; |
| 33 | |
| 34 | import jexer.bits.CellAttributes; |
| 35 | |
| 36 | /** |
| 37 | * A Line represents a single line of text on the screen, as a collection of |
| 38 | * words. |
| 39 | */ |
| 40 | public class Line { |
| 41 | |
| 42 | /** |
| 43 | * The list of words. |
| 44 | */ |
| 45 | private ArrayList<Word> words = new ArrayList<Word>(); |
| 46 | |
| 47 | /** |
| 48 | * The default color for the TEditor class. |
| 49 | */ |
| 50 | private CellAttributes defaultColor = null; |
| 51 | |
| 52 | /** |
| 53 | * The text highlighter to use. |
| 54 | */ |
| 55 | private Highlighter highlighter = null; |
| 56 | |
| 57 | /** |
| 58 | * The current cursor position on this line. |
| 59 | */ |
| 60 | private int cursor = 0; |
| 61 | |
| 62 | /** |
| 63 | * The raw text of this line, what is passed to Word to determine |
| 64 | * highlighting behavior. |
| 65 | */ |
| 66 | private StringBuilder rawText; |
| 67 | |
| 68 | /** |
| 69 | * Get a (shallow) copy of the words in this line. |
| 70 | * |
| 71 | * @return a copy of the word list |
| 72 | */ |
| 73 | public List<Word> getWords() { |
| 74 | return new ArrayList<Word>(words); |
| 75 | } |
| 76 | |
| 77 | /** |
| 78 | * Get the current cursor position. |
| 79 | * |
| 80 | * @return the cursor position |
| 81 | */ |
| 82 | public int getCursor() { |
| 83 | return cursor; |
| 84 | } |
| 85 | |
| 86 | /** |
| 87 | * Set the current cursor position. |
| 88 | * |
| 89 | * @param cursor the new cursor position |
| 90 | */ |
| 91 | public void setCursor(final int cursor) { |
| 92 | if ((cursor < 0) |
| 93 | || ((cursor >= getDisplayLength()) |
| 94 | && (getDisplayLength() > 0)) |
| 95 | ) { |
| 96 | throw new IndexOutOfBoundsException("Max length is " + |
| 97 | getDisplayLength() + ", requested position " + cursor); |
| 98 | } |
| 99 | this.cursor = cursor; |
| 100 | } |
| 101 | |
| 102 | /** |
| 103 | * Get the on-screen display length. |
| 104 | * |
| 105 | * @return the number of cells needed to display this line |
| 106 | */ |
| 107 | public int getDisplayLength() { |
| 108 | int n = rawText.length(); |
| 109 | |
| 110 | // For now just return the raw text length. |
| 111 | if (n > 0) { |
| 112 | // If we have any visible characters, add one to the display so |
| 113 | // that the cursor is immediately after the data. |
| 114 | return n + 1; |
| 115 | } |
| 116 | return n; |
| 117 | } |
| 118 | |
| 119 | /** |
| 120 | * Get the raw string that matches this line. |
| 121 | * |
| 122 | * @return the string |
| 123 | */ |
| 124 | public String getRawString() { |
| 125 | return rawText.toString(); |
| 126 | } |
| 127 | |
| 128 | /** |
| 129 | * Scan rawText and make words out of it. |
| 130 | */ |
| 131 | private void scanLine() { |
| 132 | words.clear(); |
| 133 | Word word = new Word(this.defaultColor, this.highlighter); |
| 134 | words.add(word); |
| 135 | for (int i = 0; i < rawText.length(); i++) { |
| 136 | char ch = rawText.charAt(i); |
| 137 | Word newWord = word.addChar(ch); |
| 138 | if (newWord != word) { |
| 139 | words.add(newWord); |
| 140 | word = newWord; |
| 141 | } |
| 142 | } |
| 143 | for (Word w: words) { |
| 144 | w.applyHighlight(); |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | /** |
| 149 | * Construct a new Line from an existing text string, and highlight |
| 150 | * certain strings. |
| 151 | * |
| 152 | * @param str the text string |
| 153 | * @param defaultColor the color for unhighlighted text |
| 154 | * @param highlighter the highlighter to use |
| 155 | */ |
| 156 | public Line(final String str, final CellAttributes defaultColor, |
| 157 | final Highlighter highlighter) { |
| 158 | |
| 159 | this.defaultColor = defaultColor; |
| 160 | this.highlighter = highlighter; |
| 161 | this.rawText = new StringBuilder(str); |
| 162 | |
| 163 | scanLine(); |
| 164 | } |
| 165 | |
| 166 | /** |
| 167 | * Construct a new Line from an existing text string. |
| 168 | * |
| 169 | * @param str the text string |
| 170 | * @param defaultColor the color for unhighlighted text |
| 171 | */ |
| 172 | public Line(final String str, final CellAttributes defaultColor) { |
| 173 | this(str, defaultColor, null); |
| 174 | } |
| 175 | |
| 176 | /** |
| 177 | * Decrement the cursor by one. If at the first column, do nothing. |
| 178 | * |
| 179 | * @return true if the cursor position changed |
| 180 | */ |
| 181 | public boolean left() { |
| 182 | if (cursor == 0) { |
| 183 | return false; |
| 184 | } |
| 185 | cursor--; |
| 186 | return true; |
| 187 | } |
| 188 | |
| 189 | /** |
| 190 | * Increment the cursor by one. If at the last column, do nothing. |
| 191 | * |
| 192 | * @return true if the cursor position changed |
| 193 | */ |
| 194 | public boolean right() { |
| 195 | if (getDisplayLength() == 0) { |
| 196 | return false; |
| 197 | } |
| 198 | if (cursor == getDisplayLength() - 1) { |
| 199 | return false; |
| 200 | } |
| 201 | cursor++; |
| 202 | return true; |
| 203 | } |
| 204 | |
| 205 | /** |
| 206 | * Go to the first column of this line. |
| 207 | * |
| 208 | * @return true if the cursor position changed |
| 209 | */ |
| 210 | public boolean home() { |
| 211 | if (cursor > 0) { |
| 212 | cursor = 0; |
| 213 | return true; |
| 214 | } |
| 215 | return false; |
| 216 | } |
| 217 | |
| 218 | /** |
| 219 | * Go to the last column of this line. |
| 220 | * |
| 221 | * @return true if the cursor position changed |
| 222 | */ |
| 223 | public boolean end() { |
| 224 | if (cursor != getDisplayLength() - 1) { |
| 225 | cursor = getDisplayLength() - 1; |
| 226 | if (cursor < 0) { |
| 227 | cursor = 0; |
| 228 | } |
| 229 | return true; |
| 230 | } |
| 231 | return false; |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * Delete the character under the cursor. |
| 236 | */ |
| 237 | public void del() { |
| 238 | assert (words.size() > 0); |
| 239 | |
| 240 | if (cursor < getDisplayLength()) { |
| 241 | rawText.deleteCharAt(cursor); |
| 242 | } |
| 243 | |
| 244 | // Re-scan the line to determine the new word boundaries. |
| 245 | scanLine(); |
| 246 | } |
| 247 | |
| 248 | /** |
| 249 | * Delete the character immediately preceeding the cursor. |
| 250 | */ |
| 251 | public void backspace() { |
| 252 | if (left()) { |
| 253 | del(); |
| 254 | } |
| 255 | } |
| 256 | |
| 257 | /** |
| 258 | * Insert a character at the cursor. |
| 259 | * |
| 260 | * @param ch the character to insert |
| 261 | */ |
| 262 | public void addChar(final char ch) { |
| 263 | if (cursor < getDisplayLength() - 1) { |
| 264 | rawText.insert(cursor, ch); |
| 265 | } else { |
| 266 | rawText.append(ch); |
| 267 | } |
| 268 | scanLine(); |
| 269 | cursor++; |
| 270 | } |
| 271 | |
| 272 | /** |
| 273 | * Replace a character at the cursor. |
| 274 | * |
| 275 | * @param ch the character to replace |
| 276 | */ |
| 277 | public void replaceChar(final char ch) { |
| 278 | if (cursor < getDisplayLength() - 1) { |
| 279 | rawText.setCharAt(cursor, ch); |
| 280 | } else { |
| 281 | rawText.append(ch); |
| 282 | } |
| 283 | scanLine(); |
| 284 | cursor++; |
| 285 | } |
| 286 | |
| 287 | } |