src/apps/haikudepot/textview/TextEditor.cpp

   1 /*
   2  * Copyright 2014, Stephan Aßmus <superstippi@gmx.de>.
   3  * All rights reserved. Distributed under the terms of the MIT License.
   4  */
   5
   6 #include "TextEditor.h"
   7
   8 #include <algorithm>
   9 #include <stdio.h>
  10
  11
  12 TextEditor::TextEditor()
  13         :
  14         fDocument(),
  15         fLayout(),
  16         fSelection(),
  17         fCaretAnchorX(0.0f),
  18         fStyleAtCaret(),
  19         fEditingEnabled(true)
  20 {
  21 }
  22
  23
  24 TextEditor::TextEditor(const TextEditor& other)
  25         :
  26         fDocument(other.fDocument),
  27         fLayout(other.fLayout),
  28         fSelection(other.fSelection),
  29         fCaretAnchorX(other.fCaretAnchorX),
  30         fStyleAtCaret(other.fStyleAtCaret),
  31         fEditingEnabled(other.fEditingEnabled)
  32 {
  33 }
  34
  35
  36 TextEditor::~TextEditor()
  37 {
  38 }
  39
  40
  41 TextEditor&
  42 TextEditor::operator=(const TextEditor& other)
  43 {
  44         if (this == &other)
  45                 return *this;
  46
  47         fDocument = other.fDocument;
  48         fLayout = other.fLayout;
  49         fSelection = other.fSelection;
  50         fCaretAnchorX = other.fCaretAnchorX;
  51         fStyleAtCaret = other.fStyleAtCaret;
  52         fEditingEnabled = other.fEditingEnabled;
  53         return *this;
  54 }
  55
  56
  57 bool
  58 TextEditor::operator==(const TextEditor& other) const
  59 {
  60         if (this == &other)
  61                 return true;
  62
  63         return fDocument == other.fDocument
  64                 && fLayout == other.fLayout
  65                 && fSelection == other.fSelection
  66                 && fCaretAnchorX == other.fCaretAnchorX
  67                 && fStyleAtCaret == other.fStyleAtCaret
  68                 && fEditingEnabled == other.fEditingEnabled;
  69 }
  70
  71
  72 bool
  73 TextEditor::operator!=(const TextEditor& other) const
  74 {
  75         return !(*this == other);
  76 }
  77
  78
  79 // #pragma mark -
  80
  81
  82 void
  83 TextEditor::SetDocument(const TextDocumentRef& ref)
  84 {
  85         fDocument = ref;
  86         SetSelection(TextSelection());
  87 }
  88
  89
  90 void
  91 TextEditor::SetLayout(const TextDocumentLayoutRef& ref)
  92 {
  93         fLayout = ref;
  94         SetSelection(TextSelection());
  95 }
  96
  97
  98 void
  99 TextEditor::SetEditingEnabled(bool enabled)
 100 {
 101         fEditingEnabled = enabled;
 102 }
 103
 104
 105 void
 106 TextEditor::SetCaret(BPoint location, bool extendSelection)
 107 {
 108         if (fDocument.Get() == NULL || fLayout.Get() == NULL)
 109                 return;
 110
 111         bool rightOfChar = false;
 112         int32 caretOffset = fLayout->TextOffsetAt(location.x, location.y,
 113                 rightOfChar);
 114
 115         if (rightOfChar)
 116                 caretOffset++;
 117
 118         _SetCaretOffset(caretOffset, true, extendSelection, true);
 119 }
 120
 121
 122 void
 123 TextEditor::SelectAll()
 124 {
 125         if (fDocument.Get() == NULL)
 126                 return;
 127
 128         SetSelection(TextSelection(0, fDocument->Length()));
 129 }
 130
 131
 132 void
 133 TextEditor::SetSelection(TextSelection selection)
 134 {
 135         _SetSelection(selection.Caret(), selection.Anchor(), true, true);
 136 }
 137
 138
 139 void
 140 TextEditor::SetCharacterStyle(::CharacterStyle style)
 141 {
 142         if (fStyleAtCaret == style)
 143                 return;
 144
 145         fStyleAtCaret = style;
 146
 147         if (HasSelection()) {
 148                 // TODO: Apply style to selection range
 149         }
 150 }
 151
 152
 153 void
 154 TextEditor::KeyDown(KeyEvent event)
 155 {
 156         if (fDocument.Get() == NULL)
 157                 return;
 158
 159         bool select = (event.modifiers & B_SHIFT_KEY) != 0;
 160
 161         switch (event.key) {
 162                 case B_UP_ARROW:
 163                         LineUp(select);
 164                         break;
 165
 166                 case B_DOWN_ARROW:
 167                         LineDown(select);
 168                         break;
 169
 170                 case B_LEFT_ARROW:
 171                         if (HasSelection() && !select) {
 172                                 _SetCaretOffset(
 173                                         std::min(fSelection.Caret(), fSelection.Anchor()),
 174                                         true, false, true);
 175                         } else
 176                                 _SetCaretOffset(fSelection.Caret() - 1, true, select, true);
 177                         break;
 178
 179                 case B_RIGHT_ARROW:
 180                         if (HasSelection() && !select) {
 181                                 _SetCaretOffset(
 182                                         std::max(fSelection.Caret(), fSelection.Anchor()),
 183                                         true, false, true);
 184                         } else
 185                                 _SetCaretOffset(fSelection.Caret() + 1, true, select, true);
 186                         break;
 187
 188                 case B_HOME:
 189                         LineStart(select);
 190                         break;
 191
 192                 case B_END:
 193                         LineEnd(select);
 194                         break;
 195
 196                 case B_ENTER:
 197                         Insert(fSelection.Caret(), "\n");
 198                         break;
 199
 200                 case B_TAB:
 201                         // TODO: Tab support in TextLayout
 202                         Insert(fSelection.Caret(), " ");
 203                         break;
 204
 205                 case B_ESCAPE:
 206                         break;
 207
 208                 case B_BACKSPACE:
 209                         if (HasSelection()) {
 210                                 Remove(SelectionStart(), SelectionLength());
 211                         } else {
 212                                 if (fSelection.Caret() > 0)
 213                                         Remove(fSelection.Caret() - 1, 1);
 214                         }
 215                         break;
 216
 217                 case B_DELETE:
 218                         if (HasSelection()) {
 219                                 Remove(SelectionStart(), SelectionLength());
 220                         } else {
 221                                 if (fSelection.Caret() < fDocument->Length())
 222                                         Remove(fSelection.Caret(), 1);
 223                         }
 224                         break;
 225
 226                 case B_INSERT:
 227                         // TODO: Toggle insert mode (or maybe just don't support it)
 228                         break;
 229
 230                 case B_PAGE_UP:
 231                 case B_PAGE_DOWN:
 232                 case B_SUBSTITUTE:
 233                 case B_FUNCTION_KEY:
 234                 case B_KATAKANA_HIRAGANA:
 235                 case B_HANKAKU_ZENKAKU:
 236                         break;
 237
 238                 default:
 239                         if (event.bytes != NULL && event.length > 0) {
 240                                 // Handle null-termintating the string
 241                                 BString text(event.bytes, event.length);
 242
 243                                 Replace(SelectionStart(), SelectionLength(), text);
 244                         }
 245                         break;
 246         }
 247 }
 248
 249
 250 status_t
 251 TextEditor::Insert(int32 offset, const BString& string)
 252 {
 253         if (!fEditingEnabled || fDocument.Get() == NULL)
 254                 return B_ERROR;
 255
 256         status_t ret = fDocument->Insert(offset, string, fStyleAtCaret);
 257
 258         if (ret == B_OK) {
 259                 _SetCaretOffset(offset + string.CountChars(), true, false, true);
 260
 261                 fDocument->PrintToStream();
 262         }
 263
 264         return ret;
 265 }
 266
 267
 268 status_t
 269 TextEditor::Remove(int32 offset, int32 length)
 270 {
 271         if (!fEditingEnabled || fDocument.Get() == NULL)
 272                 return B_ERROR;
 273
 274         status_t ret = fDocument->Remove(offset, length);
 275
 276         if (ret == B_OK) {
 277                 _SetCaretOffset(offset, true, false, true);
 278
 279                 fDocument->PrintToStream();
 280         }
 281
 282         return ret;
 283 }
 284
 285
 286 status_t
 287 TextEditor::Replace(int32 offset, int32 length, const BString& string)
 288 {
 289         if (!fEditingEnabled || fDocument.Get() == NULL)
 290                 return B_ERROR;
 291
 292         status_t ret = fDocument->Replace(offset, length, string);
 293
 294         if (ret == B_OK) {
 295                 _SetCaretOffset(offset + string.CountChars(), true, false, true);
 296
 297                 fDocument->PrintToStream();
 298         }
 299
 300         return ret;
 301 }
 302
 303
 304 // #pragma mark -
 305
 306
 307 void
 308 TextEditor::LineUp(bool select)
 309 {
 310         if (fLayout.Get() == NULL)
 311                 return;
 312
 313         int32 lineIndex = fLayout->LineIndexForOffset(fSelection.Caret());
 314         _MoveToLine(lineIndex - 1, select);
 315 }
 316
 317
 318 void
 319 TextEditor::LineDown(bool select)
 320 {
 321         if (fLayout.Get() == NULL)
 322                 return;
 323
 324         int32 lineIndex = fLayout->LineIndexForOffset(fSelection.Caret());
 325         _MoveToLine(lineIndex + 1, select);
 326 }
 327
 328
 329 void
 330 TextEditor::LineStart(bool select)
 331 {
 332         if (fLayout.Get() == NULL)
 333                 return;
 334
 335         int32 lineIndex = fLayout->LineIndexForOffset(fSelection.Caret());
 336         _SetCaretOffset(fLayout->FirstOffsetOnLine(lineIndex), true, select,
 337                 true);
 338 }
 339
 340
 341 void
 342 TextEditor::LineEnd(bool select)
 343 {
 344         if (fLayout.Get() == NULL)
 345                 return;
 346
 347         int32 lineIndex = fLayout->LineIndexForOffset(fSelection.Caret());
 348         _SetCaretOffset(fLayout->LastOffsetOnLine(lineIndex), true, select,
 349                 true);
 350 }
 351
 352
 353 // #pragma mark -
 354
 355
 356 bool
 357 TextEditor::HasSelection() const
 358 {
 359         return SelectionLength() > 0;
 360 }
 361
 362
 363 int32
 364 TextEditor::SelectionStart() const
 365 {
 366         return std::min(fSelection.Caret(), fSelection.Anchor());
 367 }
 368
 369
 370 int32
 371 TextEditor::SelectionEnd() const
 372 {
 373         return std::max(fSelection.Caret(), fSelection.Anchor());
 374 }
 375
 376
 377 int32
 378 TextEditor::SelectionLength() const
 379 {
 380         return SelectionEnd() - SelectionStart();
 381 }
 382
 383
 384 // #pragma mark - private
 385
 386
 387 // _MoveToLine
 388 void
 389 TextEditor::_MoveToLine(int32 lineIndex, bool select)
 390 {
 391         if (lineIndex < 0) {
 392                 // Move to beginning of line instead. Most editors do. Some only when
 393                 // selecting. Note that we are not updating the horizontal anchor here,
 394                 // even though the horizontal caret position changes. Most editors
 395                 // return to the previous horizonal offset when moving back down from
 396                 // the beginning of the line.
 397                 _SetCaretOffset(0, false, select, true);
 398                 return;
 399         }
 400         if (lineIndex >= fLayout->CountLines()) {
 401                 // Move to end of line instead, see above for why we do not update the
 402                 // horizontal anchor.
 403                 _SetCaretOffset(fDocument->Length(), false, select, true);
 404                 return;
 405         }
 406
 407         float x1;
 408         float y1;
 409         float x2;
 410         float y2;
 411         fLayout->GetLineBounds(lineIndex , x1, y1, x2, y2);
 412
 413         bool rightOfCenter;
 414         int32 textOffset = fLayout->TextOffsetAt(fCaretAnchorX, (y1 + y2) / 2,
 415                 rightOfCenter);
 416
 417         if (rightOfCenter)
 418                 textOffset++;
 419
 420         _SetCaretOffset(textOffset, false, select, true);
 421 }
 422
 423 void
 424 TextEditor::_SetCaretOffset(int32 offset, bool updateAnchor,
 425         bool lockSelectionAnchor, bool updateSelectionStyle)
 426 {
 427         if (fDocument.Get() == NULL)
 428                 return;
 429
 430         if (offset < 0)
 431                 offset = 0;
 432         int32 textLength = fDocument->Length();
 433         if (offset > textLength)
 434                 offset = textLength;
 435
 436         int32 caret = offset;
 437         int32 anchor = lockSelectionAnchor ? fSelection.Anchor() : offset;
 438         _SetSelection(caret, anchor, updateAnchor, updateSelectionStyle);
 439 }
 440
 441
 442 void
 443 TextEditor::_SetSelection(int32 caret, int32 anchor, bool updateAnchor,
 444         bool updateSelectionStyle)
 445 {
 446         if (fLayout.Get() == NULL)
 447                 return;
 448
 449         if (caret == fSelection.Caret() && anchor == fSelection.Anchor())
 450                 return;
 451
 452         fSelection.SetCaret(caret);
 453         fSelection.SetAnchor(anchor);
 454
 455         if (updateAnchor) {
 456                 float x1;
 457                 float y1;
 458                 float x2;
 459                 float y2;
 460
 461                 fLayout->GetTextBounds(caret, x1, y1, x2, y2);
 462                 fCaretAnchorX = x1;
 463         }
 464
 465         if (updateSelectionStyle)
 466                 _UpdateStyleAtCaret();
 467 }
 468
 469
 470 void
 471 TextEditor::_UpdateStyleAtCaret()
 472 {
 473         if (fDocument.Get() == NULL)
 474                 return;
 475
 476         int32 offset = fSelection.Caret() - 1;
 477         if (offset < 0)
 478                 offset = 0;
 479         SetCharacterStyle(fDocument->CharacterStyleAt(offset));
 480 }
 481
 482