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 /// FIXME
  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         // put the new stuff in the list if there is one
 158         if (undopar) {
 159                 if (before)
 160                         before->next(undopar);
 161                 else
 162                         bv->text->ownerParagraph(firstUndoParagraph(bv, undo.number_of_inset_id)->id(),
 163                                                  undopar);
 164
 165                 undopar->previous(before);
 166         } else {
 167                 // We enter here on DELETE undo operations where we have to
 168                 // substitue the second paragraph with the first if the removed
 169                 // one is the first!
 170                 if (!before && behind) {
 171                         bv->text->ownerParagraph(firstUndoParagraph(bv, undo.number_of_inset_id)->id(),
 172                                                  behind);
 173                         undopar = behind;
 174                 }
 175         }
 176
 177         // thread the end of the undo onto the par in front if any
 178         if (lastundopar) {
 179                 lastundopar->next(behind);
 180                 if (behind)
 181                         behind->previous(lastundopar);
 182         }
 183
 184
 185         // Set the cursor for redoing
 186         if (before) {
 187                 Inset * it = before->inInset();
 188                 if (it)
 189                         it->getLyXText(bv)->setCursorIntern(bv, before, 0);
 190                 else
 191                         bv->text->setCursorIntern(bv, before, 0);
 192         }
 193
 194         Paragraph * endpar = 0;
 195         // calculate the endpar for redoing the paragraphs.
 196         if (behind)
 197                 endpar = behind->next();
 198
 199         tmppar = bv->buffer()->getParFromID(undo.number_of_cursor_par);
 200         UpdatableInset* it = 0;
 201         if (undopar)
 202                 it = static_cast<UpdatableInset*>(undopar->inInset());
 203         if (it) {
 204                 it->getLyXText(bv)->redoParagraphs(bv,
 205                                                    it->getLyXText(bv)->cursor,
 206                                                    endpar);
 207                 if (tmppar) {
 208                         it = static_cast<UpdatableInset*>(tmppar->inInset());
 209                         LyXText * t;
 210                         if (it) {
 211                                 it->edit(bv);
 212                                 t = it->getLyXText(bv);
 213                         } else {
 214                                 t = bv->text;
 215                         }
 216                         t->setCursorIntern(bv, tmppar, undo.cursor_pos);
 217                         // clear any selection and set the selection cursor
 218                         // for an evt. new selection.
 219                         t->clearSelection();
 220                         t->selection.cursor = t->cursor;
 221                         t->updateCounters(bv);
 222                         bv->fitCursor();
 223                 }
 224                 bv->updateInset(it, false);
 225                 bv->text->setCursorIntern(bv, bv->text->cursor.par(),
 226                                           bv->text->cursor.pos());
 227         } else {
 228                 bv->text->redoParagraphs(bv, bv->text->cursor, endpar);
 229                 if (tmppar) {
 230                         LyXText * t;
 231                         Inset * it = tmppar->inInset();
 232                         if (it) {
 233                                 it->edit(bv);
 234                                 t = it->getLyXText(bv);
 235                         } else {
 236                                 t = bv->text;
 237                         }
 238                         t->setCursorIntern(bv, tmppar, undo.cursor_pos);
 239                         // clear any selection and set the selection cursor
 240                         // for an evt. new selection.
 241                         t->clearSelection();
 242                         t->selection.cursor = t->cursor;
 243                         t->updateCounters(bv);
 244                 }
 245         }
 246
 247         // And here it's safe enough to delete all removed paragraphs
 248         vector<Paragraph *>::iterator pit = deletelist.begin();
 249         if (pit != deletelist.end()) {
 250                         for(;pit != deletelist.end(); ++pit) {
 251                                 (*pit)->previous(0);
 252                                 (*pit)->next(0);
 253                                 delete (*pit);
 254                         }
 255                 }
 256
 257         finishUndo();
 258         bv->text->status(bv, LyXText::NEED_MORE_REFRESH);
 259         return true;
 260 }
 261
 262
 263 bool createUndo(BufferView * bv, Undo::undo_kind kind,
 264         Paragraph const * first, Paragraph const * behind, shared_ptr<Undo> & u)
 265 {
 266         lyx::Assert(first);
 267
 268         int before_number = -1;
 269         int behind_number = -1;
 270         int inset_id = -1;
 271
 272         if (first->previous())
 273                 before_number = first->previous()->id();
 274         if (behind)
 275                 behind_number = behind->id();
 276         if (first->inInset())
 277                 inset_id = first->inInset()->id();
 278
 279         Buffer * b = bv->buffer();
 280
 281         // Undo::EDIT  and Undo::FINISH are
 282         // always finished. (no overlapping there)
 283         // overlapping only with insert and delete inside one paragraph:
 284         // Nobody wants all removed  character
 285         // appear one by one when undoing.
 286         // EDIT is special since only layout information, not the
 287         // contents of a paragaph are stored.
 288         if (!undo_finished && (kind != Undo::EDIT) && (kind != Undo::FINISH)) {
 289                 // check whether storing is needed
 290                 if (!b->undostack.empty() &&
 291                     b->undostack.top()->kind == kind &&
 292                     b->undostack.top()->number_of_before_par == before_number &&
 293                     b->undostack.top()->number_of_behind_par == behind_number) {
 294                         // no undo needed
 295                         return false;
 296                 }
 297         }
 298
 299         // create a new Undo
 300         Paragraph * undopar;
 301
 302         Paragraph * start = const_cast<Paragraph *>(first);
 303         Paragraph * end = 0;
 304
 305         if (behind)
 306                 end = const_cast<Paragraph*>(behind->previous());
 307         else {
 308                 end = start;
 309                 while (end->next())
 310                         end = end->next();
 311         }
 312         if (start && end && (start != end->next()) &&
 313             ((before_number != behind_number) ||
 314                  ((before_number < 0) && (behind_number < 0))))
 315         {
 316                 Paragraph * tmppar = start;
 317                 Paragraph * tmppar2 = new Paragraph(*tmppar, true);
 318
 319                 // a memory optimization: Just store the layout information
 320                 // when only edit
 321                 if (kind == Undo::EDIT) {
 322                         tmppar2->clearContents();
 323                 }
 324
 325                 undopar = tmppar2;
 326
 327                 while (tmppar != end && tmppar->next()) {
 328                         tmppar = tmppar->next();
 329                         tmppar2->next(new Paragraph(*tmppar, true));
 330                         // a memory optimization: Just store the layout
 331                         // information when only edit
 332                         if (kind == Undo::EDIT) {
 333                                 tmppar2->clearContents();
 334                         }
 335                         tmppar2->next()->previous(tmppar2);
 336
 337                         tmppar2 = tmppar2->next();
 338                 }
 339                 tmppar2->next(0);
 340         } else
 341                 undopar = 0; // nothing to replace (undo of delete maybe)
 342
 343         int cursor_par = undoCursor(bv).par()->id();
 344         int cursor_pos =  undoCursor(bv).pos();
 345
 346         u.reset(new Undo(kind, inset_id,
 347                 before_number, behind_number,
 348                 cursor_par, cursor_pos, undopar));
 349
 350         undo_finished = false;
 351         return true;
 352 }
 353
 354 } // namespace anon
 355
 356 void finishUndo()
 357 {
 358         // makes sure the next operation will be stored
 359         undo_finished = true;
 360 }
 361
 362
 363 void freezeUndo()
 364 {
 365         // this is dangerous and for internal use only
 366         undo_frozen = true;
 367 }
 368
 369
 370 void unFreezeUndo()
 371 {
 372         // this is dangerous and for internal use only
 373         undo_frozen = false;
 374 }
 375
 376
 377 // returns false if no undo possible
 378 bool textUndo(BufferView * bv)
 379 {
 380         Buffer * b = bv->buffer();
 381
 382         if (b->undostack.empty()) {
 383                 finishNoUndo(bv);
 384                 return false;
 385         }
 386
 387         shared_ptr<Undo> undo = b->undostack.top();
 388         b->undostack.pop();
 389         finishUndo();
 390
 391         if (!undo_frozen) {
 392                 Paragraph * first = b->getParFromID(undo->number_of_before_par);
 393                 if (first && first->next())
 394                         first = first->next();
 395                 else if (!first)
 396                         first = firstUndoParagraph(bv, undo->number_of_inset_id);
 397                 if (first) {
 398                         shared_ptr<Undo> u;
 399                         if (createUndo(bv, undo->kind, first,
 400                                 b->getParFromID(undo->number_of_behind_par), u))
 401                                 b->redostack.push(u);
 402                 }
 403         }
 404
 405         // now we can unlock the inset for saftey because the inset pointer could
 406         // be changed during the undo-function. Anyway if needed we have to lock
 407         // the right inset/position if this is requested.
 408         freezeUndo();
 409         bv->unlockInset(bv->theLockingInset());
 410         bool const ret = textHandleUndo(bv, *undo.get());
 411         unFreezeUndo();
 412         return ret;
 413 }
 414
 415
 416 // returns false if no redo possible
 417 bool textRedo(BufferView * bv)
 418 {
 419         Buffer * b = bv->buffer();
 420
 421         if (b->redostack.empty()) {
 422                 finishNoUndo(bv);
 423                 return false;
 424         }
 425
 426         shared_ptr<Undo> undo = b->redostack.top();
 427         b->redostack.pop();
 428         finishUndo();
 429
 430         if (!undo_frozen) {
 431         Paragraph * first = bv->buffer()->getParFromID(undo->number_of_before_par);
 432                 if (first && first->next())
 433                         first = first->next();
 434                 else if (!first)
 435                         first = firstUndoParagraph(bv, undo->number_of_inset_id);
 436                 if (first) {
 437                         shared_ptr<Undo> u;
 438                         if (createUndo(bv, undo->kind, first,
 439                                 bv->buffer()->getParFromID(undo->number_of_behind_par), u))
 440                                 bv->buffer()->undostack.push(u);
 441                 }
 442         }
 443
 444         // now we can unlock the inset for saftey because the inset pointer could
 445         // be changed during the undo-function. Anyway if needed we have to lock
 446         // the right inset/position if this is requested.
 447         freezeUndo();
 448         bv->unlockInset(bv->theLockingInset());
 449         bool ret = textHandleUndo(bv, *undo.get());
 450         unFreezeUndo();
 451         return ret;
 452 }
 453
 454
 455 void setUndo(BufferView * bv, Undo::undo_kind kind,
 456              Paragraph const * first, Paragraph const * behind)
 457 {
 458         if (!undo_frozen) {
 459                 shared_ptr<Undo> u;
 460                 if (createUndo(bv, kind, first, behind, u))
 461                         bv->buffer()->undostack.push(u);
 462                 bv->buffer()->redostack.clear();
 463         }
 464 }
 465
 466
 467 void setRedo(BufferView * bv, Undo::undo_kind kind,
 468              Paragraph const * first, Paragraph const * behind)
 469 {
 470         shared_ptr<Undo> u;
 471         if (createUndo(bv, kind, first, behind, u))
 472                 bv->buffer()->redostack.push(u);
 473 }
 474
 475
 476 void setCursorParUndo(BufferView * bv)
 477 {
 478         setUndo(bv, Undo::FINISH, bv->text->cursor.par(),
 479                 bv->text->cursor.par()->next());
 480 }