src/textbuf.cpp

   1 /*
   2  * This file is part of OpenTTD.
   3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   4  * OpenTTD 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.
   5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   6  */
   7
   8 /** @file textbuf.cpp Textbuffer handling. */
   9
  10 #include "stdafx.h"
  11 #include <stdarg.h>
  12
  13 #include "textbuf_type.h"
  14 #include "string_func.h"
  15 #include "strings_func.h"
  16 #include "gfx_type.h"
  17 #include "gfx_func.h"
  18 #include "window_func.h"
  19 #include "core/alloc_func.hpp"
  20
  21 #include "safeguards.h"
  22
  23 /**
  24  * Try to retrieve the current clipboard contents.
  25  *
  26  * @note OS-specific function.
  27  * @param buffer Clipboard content.
  28  * @param last The pointer to the last element of the destination buffer
  29  * @return True if some text could be retrieved.
  30  */
  31 bool GetClipboardContents(char *buffer, const char *last);
  32
  33 int _caret_timer;
  34
  35
  36 /**
  37  * Checks if it is possible to delete a character.
  38  * @param backspace if set, delete the character before the caret,
  39  * otherwise, delete the character after it.
  40  * @return true if a character can be deleted in the given direction.
  41  */
  42 bool Textbuf::CanDelChar(bool backspace)
  43 {
  44         return backspace ? this->caretpos != 0 : this->caretpos < this->bytes - 1;
  45 }
  46
  47 /**
  48  * Delete a character from a textbuffer, either with 'Delete' or 'Backspace'
  49  * The character is delete from the position the caret is at
  50  * @param keycode Type of deletion, either WKC_BACKSPACE or WKC_DELETE
  51  * @return Return true on successful change of Textbuf, or false otherwise
  52  */
  53 bool Textbuf::DeleteChar(uint16 keycode)
  54 {
  55         bool word = (keycode & WKC_CTRL) != 0;
  56
  57         keycode &= ~WKC_SPECIAL_KEYS;
  58         if (keycode != WKC_BACKSPACE && keycode != WKC_DELETE) return false;
  59
  60         bool backspace = keycode == WKC_BACKSPACE;
  61
  62         if (!CanDelChar(backspace)) return false;
  63
  64         char *s = this->buf + this->caretpos;
  65         uint16 len = 0;
  66
  67         if (word) {
  68                 /* Delete a complete word. */
  69                 if (backspace) {
  70                         /* Delete whitespace and word in front of the caret. */
  71                         len = this->caretpos - (uint16)this->char_iter->Prev(StringIterator::ITER_WORD);
  72                         s -= len;
  73                 } else {
  74                         /* Delete word and following whitespace following the caret. */
  75                         len = (uint16)this->char_iter->Next(StringIterator::ITER_WORD) - this->caretpos;
  76                 }
  77                 /* Update character count. */
  78                 for (const char *ss = s; ss < s + len; Utf8Consume(&ss)) {
  79                         this->chars--;
  80                 }
  81         } else {
  82                 /* Delete a single character. */
  83                 if (backspace) {
  84                         /* Delete the last code point in front of the caret. */
  85                         s = Utf8PrevChar(s);
  86                         WChar c;
  87                         len = (uint16)Utf8Decode(&c, s);
  88                         this->chars--;
  89                 } else {
  90                         /* Delete the complete character following the caret. */
  91                         len = (uint16)this->char_iter->Next(StringIterator::ITER_CHARACTER) - this->caretpos;
  92                         /* Update character count. */
  93                         for (const char *ss = s; ss < s + len; Utf8Consume(&ss)) {
  94                                 this->chars--;
  95                         }
  96                 }
  97         }
  98
  99         /* Move the remaining characters over the marker */
 100         memmove(s, s + len, this->bytes - (s - this->buf) - len);
 101         this->bytes -= len;
 102
 103         if (backspace) this->caretpos -= len;
 104
 105         this->UpdateStringIter();
 106         this->UpdateWidth();
 107         this->UpdateCaretPosition();
 108         this->UpdateMarkedText();
 109
 110         return true;
 111 }
 112
 113 /**
 114  * Delete every character in the textbuffer
 115  */
 116 void Textbuf::DeleteAll()
 117 {
 118         memset(this->buf, 0, this->max_bytes);
 119         this->bytes = this->chars = 1;
 120         this->pixels = this->caretpos = this->caretxoffs = 0;
 121         this->markpos = this->markend = this->markxoffs = this->marklength = 0;
 122         this->UpdateStringIter();
 123 }
 124
 125 /**
 126  * Insert a character to a textbuffer. If maxwidth of the Textbuf is zero,
 127  * we don't care about the visual-length but only about the physical
 128  * length of the string
 129  * @param key Character to be inserted
 130  * @return Return true on successful change of Textbuf, or false otherwise
 131  */
 132 bool Textbuf::InsertChar(WChar key)
 133 {
 134         uint16 len = (uint16)Utf8CharLen(key);
 135         if (this->bytes + len <= this->max_bytes && this->chars + 1 <= this->max_chars) {
 136                 memmove(this->buf + this->caretpos + len, this->buf + this->caretpos, this->bytes - this->caretpos);
 137                 Utf8Encode(this->buf + this->caretpos, key);
 138                 this->chars++;
 139                 this->bytes    += len;
 140                 this->caretpos += len;
 141
 142                 this->UpdateStringIter();
 143                 this->UpdateWidth();
 144                 this->UpdateCaretPosition();
 145                 this->UpdateMarkedText();
 146                 return true;
 147         }
 148         return false;
 149 }
 150
 151 /**
 152  * Insert a string into the text buffer. If maxwidth of the Textbuf is zero,
 153  * we don't care about the visual-length but only about the physical
 154  * length of the string.
 155  * @param str String to insert.
 156  * @param marked Replace the currently marked text with the new text.
 157  * @param caret Move the caret to this point in the insertion string.
 158  * @param insert_location Position at which to insert the string.
 159  * @param replacement_end Replace all characters from #insert_location up to this location with the new string.
 160  * @return True on successful change of Textbuf, or false otherwise.
 161  */
 162 bool Textbuf::InsertString(const char *str, bool marked, const char *caret, const char *insert_location, const char *replacement_end)
 163 {
 164         uint16 insertpos = (marked && this->marklength != 0) ? this->markpos : this->caretpos;
 165         if (insert_location != nullptr) {
 166                 insertpos = insert_location - this->buf;
 167                 if (insertpos > this->bytes) return false;
 168
 169                 if (replacement_end != nullptr) {
 170                         this->DeleteText(insertpos, replacement_end - this->buf, str == nullptr);
 171                 }
 172         } else {
 173                 if (marked) this->DiscardMarkedText(str == nullptr);
 174         }
 175
 176         if (str == nullptr) return false;
 177
 178         uint16 bytes = 0, chars = 0;
 179         WChar c;
 180         for (const char *ptr = str; (c = Utf8Consume(&ptr)) != '\0';) {
 181                 if (!IsValidChar(c, this->afilter)) break;
 182
 183                 byte len = Utf8CharLen(c);
 184                 if (this->bytes + bytes + len > this->max_bytes) break;
 185                 if (this->chars + chars + 1   > this->max_chars) break;
 186
 187                 bytes += len;
 188                 chars++;
 189
 190                 /* Move caret if needed. */
 191                 if (ptr == caret) this->caretpos = insertpos + bytes;
 192         }
 193
 194         if (bytes == 0) return false;
 195
 196         if (marked) {
 197                 this->markpos = insertpos;
 198                 this->markend = insertpos + bytes;
 199         }
 200
 201         memmove(this->buf + insertpos + bytes, this->buf + insertpos, this->bytes - insertpos);
 202         memcpy(this->buf + insertpos, str, bytes);
 203
 204         this->bytes += bytes;
 205         this->chars += chars;
 206         if (!marked && caret == nullptr) this->caretpos += bytes;
 207         assert(this->bytes <= this->max_bytes);
 208         assert(this->chars <= this->max_chars);
 209         this->buf[this->bytes - 1] = '\0'; // terminating zero
 210
 211         this->UpdateStringIter();
 212         this->UpdateWidth();
 213         this->UpdateCaretPosition();
 214         this->UpdateMarkedText();
 215
 216         return true;
 217 }
 218
 219 /**
 220  * Insert a chunk of text from the clipboard onto the textbuffer. Get TEXT clipboard
 221  * and append this up to the maximum length (either absolute or screenlength). If maxlength
 222  * is zero, we don't care about the screenlength but only about the physical length of the string
 223  * @return true on successful change of Textbuf, or false otherwise
 224  */
 225 bool Textbuf::InsertClipboard()
 226 {
 227         char utf8_buf[512];
 228
 229         if (!GetClipboardContents(utf8_buf, lastof(utf8_buf))) return false;
 230
 231         return this->InsertString(utf8_buf, false);
 232 }
 233
 234 /**
 235  * Delete a part of the text.
 236  * @param from Start of the text to delete.
 237  * @param to End of the text to delete.
 238  * @param update Set to true if the internal state should be updated.
 239  */
 240 void Textbuf::DeleteText(uint16 from, uint16 to, bool update)
 241 {
 242         uint c = 0;
 243         const char *s = this->buf + from;
 244         while (s < this->buf + to) {
 245                 Utf8Consume(&s);
 246                 c++;
 247         }
 248
 249         /* Strip marked characters from buffer. */
 250         memmove(this->buf + from, this->buf + to, this->bytes - to);
 251         this->bytes -= to - from;
 252         this->chars -= c;
 253
 254         /* Fixup caret if needed. */
 255         if (this->caretpos > from) {
 256                 if (this->caretpos <= to) {
 257                         this->caretpos = from;
 258                 } else {
 259                         this->caretpos -= to - from;
 260                 }
 261         }
 262
 263         if (update) {
 264                 this->UpdateStringIter();
 265                 this->UpdateCaretPosition();
 266                 this->UpdateMarkedText();
 267         }
 268 }
 269
 270 /**
 271  * Discard any marked text.
 272  * @param update Set to true if the internal state should be updated.
 273  */
 274 void Textbuf::DiscardMarkedText(bool update)
 275 {
 276         if (this->markend == 0) return;
 277
 278         this->DeleteText(this->markpos, this->markend, update);
 279         this->markpos = this->markend = this->markxoffs = this->marklength = 0;
 280 }
 281
 282 /** Update the character iter after the text has changed. */
 283 void Textbuf::UpdateStringIter()
 284 {
 285         this->char_iter->SetString(this->buf);
 286         size_t pos = this->char_iter->SetCurPosition(this->caretpos);
 287         this->caretpos = pos == StringIterator::END ? 0 : (uint16)pos;
 288 }
 289
 290 /** Update pixel width of the text. */
 291 void Textbuf::UpdateWidth()
 292 {
 293         this->pixels = GetStringBoundingBox(this->buf, FS_NORMAL).width;
 294 }
 295
 296 /** Update pixel position of the caret. */
 297 void Textbuf::UpdateCaretPosition()
 298 {
 299         this->caretxoffs = this->chars > 1 ? GetCharPosInString(this->buf, this->buf + this->caretpos, FS_NORMAL).x : 0;
 300 }
 301
 302 /** Update pixel positions of the marked text area. */
 303 void Textbuf::UpdateMarkedText()
 304 {
 305         if (this->markend != 0) {
 306                 this->markxoffs  = GetCharPosInString(this->buf, this->buf + this->markpos, FS_NORMAL).x;
 307                 this->marklength = GetCharPosInString(this->buf, this->buf + this->markend, FS_NORMAL).x - this->markxoffs;
 308         } else {
 309                 this->markxoffs = this->marklength = 0;
 310         }
 311 }
 312
 313 /**
 314  * Handle text navigation with arrow keys left/right.
 315  * This defines where the caret will blink and the next character interaction will occur
 316  * @param keycode Direction in which navigation occurs (WKC_CTRL |) WKC_LEFT, (WKC_CTRL |) WKC_RIGHT, WKC_END, WKC_HOME
 317  * @return Return true on successful change of Textbuf, or false otherwise
 318  */
 319 bool Textbuf::MovePos(uint16 keycode)
 320 {
 321         switch (keycode) {
 322                 case WKC_LEFT:
 323                 case WKC_CTRL | WKC_LEFT: {
 324                         if (this->caretpos == 0) break;
 325
 326                         size_t pos = this->char_iter->Prev(keycode & WKC_CTRL ? StringIterator::ITER_WORD : StringIterator::ITER_CHARACTER);
 327                         if (pos == StringIterator::END) return true;
 328
 329                         this->caretpos = (uint16)pos;
 330                         this->UpdateCaretPosition();
 331                         return true;
 332                 }
 333
 334                 case WKC_RIGHT:
 335                 case WKC_CTRL | WKC_RIGHT: {
 336                         if (this->caretpos >= this->bytes - 1) break;
 337
 338                         size_t pos = this->char_iter->Next(keycode & WKC_CTRL ? StringIterator::ITER_WORD : StringIterator::ITER_CHARACTER);
 339                         if (pos == StringIterator::END) return true;
 340
 341                         this->caretpos = (uint16)pos;
 342                         this->UpdateCaretPosition();
 343                         return true;
 344                 }
 345
 346                 case WKC_HOME:
 347                         this->caretpos = 0;
 348                         this->char_iter->SetCurPosition(this->caretpos);
 349                         this->UpdateCaretPosition();
 350                         return true;
 351
 352                 case WKC_END:
 353                         this->caretpos = this->bytes - 1;
 354                         this->char_iter->SetCurPosition(this->caretpos);
 355                         this->UpdateCaretPosition();
 356                         return true;
 357
 358                 default:
 359                         break;
 360         }
 361
 362         return false;
 363 }
 364
 365 /**
 366  * Initialize the textbuffer by supplying it the buffer to write into
 367  * and the maximum length of this buffer
 368  * @param max_bytes maximum size in bytes, including terminating '\0'
 369  * @param max_chars maximum size in chars, including terminating '\0'
 370  */
 371 Textbuf::Textbuf(uint16 max_bytes, uint16 max_chars)
 372         : buf(MallocT<char>(max_bytes))
 373 {
 374         assert(max_bytes != 0);
 375         assert(max_chars != 0);
 376
 377         this->char_iter = StringIterator::Create();
 378
 379         this->afilter    = CS_ALPHANUMERAL;
 380         this->max_bytes  = max_bytes;
 381         this->max_chars  = max_chars == UINT16_MAX ? max_bytes : max_chars;
 382         this->caret      = true;
 383         this->DeleteAll();
 384 }
 385
 386 Textbuf::~Textbuf()
 387 {
 388         delete this->char_iter;
 389         free(this->buf);
 390 }
 391
 392 /**
 393  * Render a string into the textbuffer.
 394  * @param string String
 395  */
 396 void Textbuf::Assign(StringID string)
 397 {
 398         GetString(this->buf, string, &this->buf[this->max_bytes - 1]);
 399         this->UpdateSize();
 400 }
 401
 402 /**
 403  * Copy a string into the textbuffer.
 404  * @param text Source.
 405  */
 406 void Textbuf::Assign(const char *text)
 407 {
 408         strecpy(this->buf, text, &this->buf[this->max_bytes - 1]);
 409         this->UpdateSize();
 410 }
 411
 412 /**
 413  * Print a formatted string into the textbuffer.
 414  */
 415 void Textbuf::Print(const char *format, ...)
 416 {
 417         va_list va;
 418         va_start(va, format);
 419         vseprintf(this->buf, &this->buf[this->max_bytes - 1], format, va);
 420         va_end(va);
 421         this->UpdateSize();
 422 }
 423
 424
 425 /**
 426  * Update Textbuf type with its actual physical character and screenlength
 427  * Get the count of characters in the string as well as the width in pixels.
 428  * Useful when copying in a larger amount of text at once
 429  */
 430 void Textbuf::UpdateSize()
 431 {
 432         const char *buf = this->buf;
 433
 434         this->chars = this->bytes = 1; // terminating zero
 435
 436         WChar c;
 437         while ((c = Utf8Consume(&buf)) != '\0') {
 438                 this->bytes += Utf8CharLen(c);
 439                 this->chars++;
 440         }
 441         assert(this->bytes <= this->max_bytes);
 442         assert(this->chars <= this->max_chars);
 443
 444         this->caretpos = this->bytes - 1;
 445         this->UpdateStringIter();
 446         this->UpdateWidth();
 447         this->UpdateMarkedText();
 448
 449         this->UpdateCaretPosition();
 450 }
 451
 452 /**
 453  * Handle the flashing of the caret.
 454  * @return True if the caret state changes.
 455  */
 456 bool Textbuf::HandleCaret()
 457 {
 458         /* caret changed? */
 459         bool b = !!(_caret_timer & 0x20);
 460
 461         if (b != this->caret) {
 462                 this->caret = b;
 463                 return true;
 464         }
 465         return false;
 466 }
 467
 468 HandleKeyPressResult Textbuf::HandleKeyPress(WChar key, uint16 keycode)
 469 {
 470         bool edited = false;
 471
 472         switch (keycode) {
 473                 case WKC_ESC: return HKPR_CANCEL;
 474
 475                 case WKC_RETURN: case WKC_NUM_ENTER: return HKPR_CONFIRM;
 476
 477                 case (WKC_CTRL | 'V'):
 478                         edited = this->InsertClipboard();
 479                         break;
 480
 481                 case (WKC_CTRL | 'U'):
 482                         this->DeleteAll();
 483                         edited = true;
 484                         break;
 485
 486                 case WKC_BACKSPACE: case WKC_DELETE:
 487                 case WKC_CTRL | WKC_BACKSPACE: case WKC_CTRL | WKC_DELETE:
 488                         edited = this->DeleteChar(keycode);
 489                         break;
 490
 491                 case WKC_LEFT: case WKC_RIGHT: case WKC_END: case WKC_HOME:
 492                 case WKC_CTRL | WKC_LEFT: case WKC_CTRL | WKC_RIGHT:
 493                         this->MovePos(keycode);
 494                         break;
 495
 496                 default:
 497                         if (IsValidChar(key, this->afilter)) {
 498                                 edited = this->InsertChar(key);
 499                         } else {
 500                                 return HKPR_NOT_HANDLED;
 501                         }
 502                         break;
 503         }
 504
 505         return edited ? HKPR_EDITING : HKPR_CURSOR;
 506 }