src/undo_funcs.C

   1 /* This file is part of
   2  * ======================================================
   3  *
   4  *           LyX, The Document Processor
   5  *
   6  *           Copyright 1995-2001 The LyX Team.
   7  *
   8  * ====================================================== */
   9
  10 #include <config.h>
  11
  12 #ifdef __GNUG__
  13 #pragma implementation
  14 #endif
  15
  16 #include "undo_funcs.h"
  17 #include "lyxtext.h"
  18 #include "BufferView.h"
  19 #include "buffer.h"
  20 #include "insets/inset.h"
  21 #include "debug.h"
  22 #include "support/LAssert.h"
  23
  24 #include "iterators.h"
  25
  26 #include <vector>
  27
  28 using std::vector;
  29 using boost::shared_ptr;
  30
  31
  32 /// the flag used by FinishUndo();
  33 bool undo_finished;
  34 /// whether actions are not added to the undo stacks
  35 bool undo_frozen;
  36
  37 namespace {
  38
  39 /// utility to return the cursor
  40 LyXCursor const & undoCursor(BufferView * bv)
  41 {
  42         if (bv->theLockingInset())
  43                 return bv->theLockingInset()->cursor(bv);
  44         return bv->text->cursor;
  45 }
  46
  47 /**
  48  * returns a pointer to the very first Paragraph depending of where we are
  49  * so it will return the first paragraph of the buffer or the first paragraph
  50  * of the textinset we're in.
  51  */
  52 Paragraph * firstUndoParagraph(BufferView * bv, int inset_id)
  53 {
  54         Inset * inset = bv->buffer()->getInsetFromID(inset_id);
  55         if (inset) {
  56                 Paragraph * result = inset->getFirstParagraph(0);
  57                 if (result)
  58                         return result;
  59         }
  60         return bv->text->ownerParagraph();
  61 }
  62
  63
  64 /**
  65  * Finish the undo operation in the case there was no entry
  66  * on the stack to perform.
  67  */
  68 void finishNoUndo(BufferView * bv)
  69 {
  70         freezeUndo();
  71         bv->unlockInset(bv->theLockingInset());
  72         finishUndo();
  73         bv->text->status(bv, LyXText::NEED_MORE_REFRESH);
  74         unFreezeUndo();
  75 }
  76
  77
  78 // returns false if no undo possible
  79 bool textHandleUndo(BufferView * bv, Undo & undo)
  80 {
  81         Buffer * b = bv->buffer();
  82
  83         Paragraph * before =
  84                 b->getParFromID(undo.number_of_before_par);
  85         Paragraph * behind =
  86                 b->getParFromID(undo.number_of_behind_par);
  87         Paragraph * tmppar;
  88         Paragraph * tmppar2;
  89
  90         // if there's no before take the beginning
  91         // of the document for redoing
  92         if (!before) {
  93                 LyXText * t = bv->text;
  94                 int num = undo.number_of_inset_id;
  95                 if (undo.number_of_inset_id >= 0) {
  96                         Inset * in = bv->buffer()->getInsetFromID(num);
  97                         if (in) {
  98                                 t = in->getLyXText(bv);
  99                         } else {
 100                                 num = -1;
 101                         }
 102                 }
 103                 t->setCursorIntern(bv, firstUndoParagraph(bv, num), 0);
 104         }
 105
 106         // replace the paragraphs with the undo informations
 107
 108         Paragraph * undopar = undo.par;
 109         undo.par = 0;   /* otherwise the undo destructor would
 110                            delete the paragraph */
 111
 112         // get last undo par and set the right(new) inset-owner of the
 113         // paragraph if there is any. This is not needed if we don't have
 114         // a paragraph before because then in is automatically done in the
 115         // function which assigns the first paragraph to an InsetText. (Jug)
 116         Paragraph * lastundopar = undopar;
 117         if (lastundopar) {
 118                 Inset * in = 0;
 119                 if (before)
 120                         in = before->inInset();
 121                 else if (undo.number_of_inset_id >= 0)
 122                         in = bv->buffer()->getInsetFromID(undo.number_of_inset_id);
 123                 lastundopar->setInsetOwner(in);
 124                 while (lastundopar->next()) {
 125                         lastundopar = lastundopar->next();
 126                         lastundopar->setInsetOwner(in);
 127                 }
 128         }
 129
 130         vector<Paragraph *> deletelist;
 131
 132         Paragraph * deletepar;
 133
 134         // now add old paragraphs to be deleted
 135         if (before != behind || (!behind && !before)) {
 136                 if (before)
 137                         deletepar = before->next();
 138                 else
 139                         deletepar = firstUndoParagraph(bv, undo.number_of_inset_id);
 140                 tmppar2 = undopar;
 141                 while (deletepar && deletepar != behind) {
 142                         deletelist.push_back(deletepar);
 143                         tmppar = deletepar;
 144                         deletepar = deletepar->next();
 145
 146                         // a memory optimization for edit:
 147                         // Only layout information
 148                         // is stored in the undo. So restore
 149                         // the text informations.
 150                         if (undo.kind == Undo::EDIT) {
 151                                 tmppar2->setContentsFromPar(tmppar);
 152                                 tmppar2 = tmppar2->next();
 153                         }
 154                 }
 155         }
 156
 157         // The order here is VERY IMPORTANT. We have to set the right
 158         // next/prev pointer in the paragraphs so that a rebuild of
 159         // the LyXText works!!!
 160
 161         // thread the end of the undo onto the par in front if any
 162         if (lastundopar) {
 163                 lastundopar->next(behind);
 164                 if (behind)
 165                         behind->previous(lastundopar);
 166         }
 167
 168         // put the new stuff in the list if there is one
 169         if (undopar) {
 170                 undopar->previous(before);
 171                 if (before)
 172                         before->next(undopar);
 173                 else
 174                         bv->text->ownerParagraph(firstUndoParagraph(bv, undo.number_of_inset_id)->id(),
 175                                                  undopar);
 176
 177         } else {
 178                 // We enter here on DELETE undo operations where we have to
 179                 // substitue the second paragraph with the first if the removed
 180                 // one is the first!
 181                 if (!before && behind) {
 182                         bv->text->ownerParagraph(firstUndoParagraph(bv, undo.number_of_inset_id)->id(),
 183                                                  behind);
 184                         undopar = behind;
 185                 }
 186         }
 187
 188
 189         // Set the cursor for redoing
 190         if (before) { // if we have a par before the undopar
 191                 Inset * it = before->inInset();
 192                 if (it)
 193                         it->getLyXText(bv)->setCursorIntern(bv, before, 0);
 194                 else
 195                         bv->text->setCursorIntern(bv, before, 0);
 196         } else { // otherwise this is the first one and we start here
 197                 Inset * it = undopar->inInset();
 198                 if (it)
 199                         it->getLyXText(bv)->setCursorIntern(bv, undopar, 0);
 200                 else
 201                         bv->text->setCursorIntern(bv, undopar, 0);
 202         }
 203
 204         Paragraph * endpar = 0;
 205         // calculate the endpar for redoing the paragraphs.
 206         if (behind)
 207                 endpar = behind->next();
 208
 209         tmppar = bv->buffer()->getParFromID(undo.number_of_cursor_par);
 210         UpdatableInset* it = 0;
 211         if (undopar)
 212                 it = static_cast<UpdatableInset*>(undopar->inInset());
 213         if (it) {
 214                 it->getLyXText(bv)->redoParagraphs(bv,
 215                                                    it->getLyXText(bv)->cursor,
 216                                                    endpar);
 217                 if (tmppar) {
 218                         it = static_cast<UpdatableInset*>(tmppar->inInset());
 219                         LyXText * t;
 220                         if (it) {
 221                                 it->edit(bv);
 222                                 t = it->getLyXText(bv);
 223                         } else {
 224                                 t = bv->text;
 225                         }
 226                         t->setCursorIntern(bv, tmppar, undo.cursor_pos);
 227                         // clear any selection and set the selection cursor
 228                         // for an evt. new selection.
 229                         t->clearSelection();
 230                         t->selection.cursor = t->cursor;
 231                         t->updateCounters(bv);
 232                         bv->fitCursor();
 233                 }
 234                 bv->updateInset(it, false);
 235                 bv->text->setCursorIntern(bv, bv->text->cursor.par(),
 236                                           bv->text->cursor.pos());
 237         } else {
 238                 bv->text->redoParagraphs(bv, bv->text->cursor, endpar);
 239                 if (tmppar) {
 240                         LyXText * t;
 241                         Inset * it = tmppar->inInset();
 242                         if (it) {
 243                                 it->edit(bv);
 244                                 t = it->getLyXText(bv);
 245                         } else {
 246                                 t = bv->text;
 247                         }
 248                         t->setCursorIntern(bv, tmppar, undo.cursor_pos);
 249                         // clear any selection and set the selection cursor
 250                         // for an evt. new selection.
 251                         t->clearSelection();
 252                         t->selection.cursor = t->cursor;
 253                         t->updateCounters(bv);
 254                 }
 255         }
 256
 257         // And here it's safe enough to delete all removed paragraphs
 258         vector<Paragraph *>::iterator pit = deletelist.begin();
 259         if (pit != deletelist.end()) {
 260                         for(;pit != deletelist.end(); ++pit) {
 261                                 (*pit)->previous(0);
 262                                 (*pit)->next(0);
 263                                 delete (*pit);
 264                         }
 265                 }
 266
 267         finishUndo();
 268         bv->text->status(bv, LyXText::NEED_MORE_REFRESH);
 269         return true;
 270 }
 271
 272
 273 bool createUndo(BufferView * bv, Undo::undo_kind kind,
 274         Paragraph const * first, Paragraph const * behind, shared_ptr<Undo> & u)
 275 {
 276         lyx::Assert(first);
 277
 278         int before_number = -1;
 279         int behind_number = -1;
 280         int inset_id = -1;
 281
 282         if (first->previous())
 283                 before_number = first->previous()->id();
 284         if (behind)
 285                 behind_number = behind->id();
 286         if (first->inInset())
 287                 inset_id = first->inInset()->id();
 288
 289         Buffer * b = bv->buffer();
 290
 291         // Undo::EDIT  and Undo::FINISH are
 292         // always finished. (no overlapping there)
 293         // overlapping only with insert and delete inside one paragraph:
 294         // Nobody wants all removed  character
 295         // appear one by one when undoing.
 296         // EDIT is special since only layout information, not the
 297         // contents of a paragaph are stored.
 298         if (!undo_finished && (kind != Undo::EDIT) && (kind != Undo::FINISH)) {
 299                 // check whether storing is needed
 300                 if (!b->undostack.empty() &&
 301                     b->undostack.top()->kind == kind &&
 302                     b->undostack.top()->number_of_before_par == before_number &&
 303                     b->undostack.top()->number_of_behind_par == behind_number) {
 304                         // no undo needed
 305                         return false;
 306                 }
 307         }
 308
 309         // create a new Undo
 310         Paragraph * undopar;
 311
 312         Paragraph * start = const_cast<Paragraph *>(first);
 313         Paragraph * end = 0;
 314
 315         if (behind)
 316                 end = const_cast<Paragraph*>(behind->previous());
 317         else {
 318                 end = start;
 319                 while (end->next())
 320                         end = end->next();
 321         }
 322         if (start && end && (start != end->next()) &&
 323             ((before_number != behind_number) ||
 324                  ((before_number < 0) && (behind_number < 0))))
 325         {
 326                 Paragraph * tmppar = start;
 327                 Paragraph * tmppar2 = new Paragraph(*tmppar, true);
 328
 329                 // a memory optimization: Just store the layout information
 330                 // when only edit
 331                 if (kind == Undo::EDIT) {
 332                         tmppar2->clearContents();
 333                 }
 334
 335                 undopar = tmppar2;
 336
 337                 while (tmppar != end && tmppar->next()) {
 338                         tmppar = tmppar->next();
 339                         tmppar2->next(new Paragraph(*tmppar, true));
 340                         // a memory optimization: Just store the layout
 341                         // information when only edit
 342                         if (kind == Undo::EDIT) {
 343                                 tmppar2->clearContents();
 344                         }
 345                         tmppar2->next()->previous(tmppar2);
 346
 347                         tmppar2 = tmppar2->next();
 348                 }
 349                 tmppar2->next(0);
 350         } else
 351                 undopar = 0; // nothing to replace (undo of delete maybe)
 352
 353         int cursor_par = undoCursor(bv).par()->id();
 354         int cursor_pos =  undoCursor(bv).pos();
 355
 356         u.reset(new Undo(kind, inset_id,
 357                 before_number, behind_number,
 358                 cursor_par, cursor_pos, undopar));
 359
 360         undo_finished = false;
 361         return true;
 362 }
 363
 364 } // namespace anon
 365
 366 void finishUndo()
 367 {
 368         // makes sure the next operation will be stored
 369         undo_finished = true;
 370 }
 371
 372
 373 void freezeUndo()
 374 {
 375         // this is dangerous and for internal use only
 376         undo_frozen = true;
 377 }
 378
 379
 380 void unFreezeUndo()
 381 {
 382         // this is dangerous and for internal use only
 383         undo_frozen = false;
 384 }
 385
 386
 387 // returns false if no undo possible
 388 bool textUndo(BufferView * bv)
 389 {
 390         Buffer * b = bv->buffer();
 391
 392         if (b->undostack.empty()) {
 393                 finishNoUndo(bv);
 394                 return false;
 395         }
 396
 397         shared_ptr<Undo> undo = b->undostack.top();
 398         b->undostack.pop();
 399         finishUndo();
 400
 401         if (!undo_frozen) {
 402                 Paragraph * first = b->getParFromID(undo->number_of_before_par);
 403                 if (first && first->next())
 404                         first = first->next();
 405                 else if (!first)
 406                         first = firstUndoParagraph(bv, undo->number_of_inset_id);
 407                 if (first) {
 408                         shared_ptr<Undo> u;
 409                         if (createUndo(bv, undo->kind, first,
 410                                 b->getParFromID(undo->number_of_behind_par), u))
 411                                 b->redostack.push(u);
 412                 }
 413         }
 414
 415         // now we can unlock the inset for saftey because the inset pointer could
 416         // be changed during the undo-function. Anyway if needed we have to lock
 417         // the right inset/position if this is requested.
 418         freezeUndo();
 419         bv->unlockInset(bv->theLockingInset());
 420         bool const ret = textHandleUndo(bv, *undo.get());
 421         unFreezeUndo();
 422         return ret;
 423 }
 424
 425
 426 // returns false if no redo possible
 427 bool textRedo(BufferView * bv)
 428 {
 429         Buffer * b = bv->buffer();
 430
 431         if (b->redostack.empty()) {
 432                 finishNoUndo(bv);
 433                 return false;
 434         }
 435
 436         shared_ptr<Undo> undo = b->redostack.top();
 437         b->redostack.pop();
 438         finishUndo();
 439
 440         if (!undo_frozen) {
 441         Paragraph * first = bv->buffer()->getParFromID(undo->number_of_before_par);
 442                 if (first && first->next())
 443                         first = first->next();
 444                 else if (!first)
 445                         first = firstUndoParagraph(bv, undo->number_of_inset_id);
 446                 if (first) {
 447                         shared_ptr<Undo> u;
 448                         if (createUndo(bv, undo->kind, first,
 449                                 bv->buffer()->getParFromID(undo->number_of_behind_par), u))
 450                                 bv->buffer()->undostack.push(u);
 451                 }
 452         }
 453
 454         // now we can unlock the inset for saftey because the inset pointer could
 455         // be changed during the undo-function. Anyway if needed we have to lock
 456         // the right inset/position if this is requested.
 457         freezeUndo();
 458         bv->unlockInset(bv->theLockingInset());
 459         bool ret = textHandleUndo(bv, *undo.get());
 460         unFreezeUndo();
 461         return ret;
 462 }
 463
 464
 465 void setUndo(BufferView * bv, Undo::undo_kind kind,
 466              Paragraph const * first, Paragraph const * behind)
 467 {
 468         if (!undo_frozen) {
 469                 shared_ptr<Undo> u;
 470                 if (createUndo(bv, kind, first, behind, u))
 471                         bv->buffer()->undostack.push(u);
 472                 bv->buffer()->redostack.clear();
 473         }
 474 }
 475
 476
 477 void setRedo(BufferView * bv, Undo::undo_kind kind,
 478              Paragraph const * first, Paragraph const * behind)
 479 {
 480         shared_ptr<Undo> u;
 481         if (createUndo(bv, kind, first, behind, u))
 482                 bv->buffer()->redostack.push(u);
 483 }
 484
 485
 486 void setCursorParUndo(BufferView * bv)
 487 {
 488         setUndo(bv, Undo::FINISH, bv->text->cursor.par(),
 489                 bv->text->cursor.par()->next());
 490 }