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 * tmppar3 = 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 * tmppar4 = tmppar3;
 117         if (tmppar4) {
 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                 tmppar4->setInsetOwner(in);
 124                 while (tmppar4->next()) {
 125                         tmppar4 = tmppar4->next();
 126                         tmppar4->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 = tmppar3;
 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 (tmppar3) {
 159                 if (before)
 160                         before->next(tmppar3);
 161                 else
 162                         bv->text->ownerParagraph(firstUndoParagraph(bv, undo.number_of_inset_id)->id(),
 163                                                  tmppar3);
 164
 165                 tmppar3->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                         tmppar3 = behind;
 174                 }
 175         }
 176         if (tmppar4) {
 177                 tmppar4->next(behind);
 178                 if (behind)
 179                         behind->previous(tmppar4);
 180         }
 181
 182
 183         // Set the cursor for redoing
 184         if (before) {
 185                 Inset * it = before->inInset();
 186                 if (it)
 187                         it->getLyXText(bv)->setCursorIntern(bv, before, 0);
 188                 else
 189                         bv->text->setCursorIntern(bv, before, 0);
 190         }
 191
 192         Paragraph * endpar = 0;
 193         // calculate the endpar for redoing the paragraphs.
 194         if (behind)
 195                 endpar = behind->next();
 196
 197         tmppar = bv->buffer()->getParFromID(undo.number_of_cursor_par);
 198         UpdatableInset* it = 0;
 199         if (tmppar3)
 200                 it = static_cast<UpdatableInset*>(tmppar3->inInset());
 201         if (it) {
 202                 it->getLyXText(bv)->redoParagraphs(bv,
 203                                                    it->getLyXText(bv)->cursor,
 204                                                    endpar);
 205                 if (tmppar) {
 206                         it = static_cast<UpdatableInset*>(tmppar->inInset());
 207                         LyXText * t;
 208                         if (it) {
 209                                 it->edit(bv);
 210                                 t = it->getLyXText(bv);
 211                         } else {
 212                                 t = bv->text;
 213                         }
 214                         t->setCursorIntern(bv, tmppar, undo.cursor_pos);
 215                         // clear any selection and set the selection cursor
 216                         // for an evt. new selection.
 217                         t->clearSelection();
 218                         t->selection.cursor = t->cursor;
 219                         t->updateCounters(bv);
 220                         bv->fitCursor();
 221                 }
 222                 bv->updateInset(it, false);
 223                 bv->text->setCursorIntern(bv, bv->text->cursor.par(),
 224                                           bv->text->cursor.pos());
 225         } else {
 226                 bv->text->redoParagraphs(bv, bv->text->cursor, endpar);
 227                 if (tmppar) {
 228                         LyXText * t;
 229                         Inset * it = tmppar->inInset();
 230                         if (it) {
 231                                 it->edit(bv);
 232                                 t = it->getLyXText(bv);
 233                         } else {
 234                                 t = bv->text;
 235                         }
 236                         t->setCursorIntern(bv, tmppar, undo.cursor_pos);
 237                         // clear any selection and set the selection cursor
 238                         // for an evt. new selection.
 239                         t->clearSelection();
 240                         t->selection.cursor = t->cursor;
 241                         t->updateCounters(bv);
 242                 }
 243         }
 244
 245         // And here it's safe enough to delete all removed paragraphs
 246         vector<Paragraph *>::iterator pit = deletelist.begin();
 247         if (pit != deletelist.end()) {
 248                         for(;pit != deletelist.end(); ++pit) {
 249                                 (*pit)->previous(0);
 250                                 (*pit)->next(0);
 251                                 delete (*pit);
 252                         }
 253                 }
 254
 255         finishUndo();
 256         bv->text->status(bv, LyXText::NEED_MORE_REFRESH);
 257         return true;
 258 }
 259
 260
 261 bool createUndo(BufferView * bv, Undo::undo_kind kind,
 262         Paragraph const * first, Paragraph const * behind, shared_ptr<Undo> & u)
 263 {
 264         lyx::Assert(first);
 265
 266         int before_number = -1;
 267         int behind_number = -1;
 268         int inset_id = -1;
 269
 270         if (first->previous())
 271                 before_number = first->previous()->id();
 272         if (behind)
 273                 behind_number = behind->id();
 274         if (first->inInset())
 275                 inset_id = first->inInset()->id();
 276
 277         Buffer * b = bv->buffer();
 278
 279         // Undo::EDIT  and Undo::FINISH are
 280         // always finished. (no overlapping there)
 281         // overlapping only with insert and delete inside one paragraph:
 282         // Nobody wants all removed  character
 283         // appear one by one when undoing.
 284         // EDIT is special since only layout information, not the
 285         // contents of a paragaph are stored.
 286         if (!undo_finished && (kind != Undo::EDIT) && (kind != Undo::FINISH)) {
 287                 // check whether storing is needed
 288                 if (!b->undostack.empty() &&
 289                     b->undostack.top()->kind == kind &&
 290                     b->undostack.top()->number_of_before_par == before_number &&
 291                     b->undostack.top()->number_of_behind_par == behind_number) {
 292                         // no undo needed
 293                         return false;
 294                 }
 295         }
 296
 297         // create a new Undo
 298         Paragraph * undopar;
 299
 300         Paragraph * start = const_cast<Paragraph *>(first);
 301         Paragraph * end = 0;
 302
 303         if (behind)
 304                 end = const_cast<Paragraph*>(behind->previous());
 305         else {
 306                 end = start;
 307                 while (end->next())
 308                         end = end->next();
 309         }
 310         if (start && end && (start != end->next()) &&
 311             ((before_number != behind_number) ||
 312                  ((before_number < 0) && (behind_number < 0))))
 313         {
 314                 Paragraph * tmppar = start;
 315                 Paragraph * tmppar2 = new Paragraph(*tmppar, true);
 316
 317                 // a memory optimization: Just store the layout information
 318                 // when only edit
 319                 if (kind == Undo::EDIT) {
 320                         tmppar2->clearContents();
 321                 }
 322
 323                 undopar = tmppar2;
 324
 325                 while (tmppar != end && tmppar->next()) {
 326                         tmppar = tmppar->next();
 327                         tmppar2->next(new Paragraph(*tmppar, true));
 328                         // a memory optimization: Just store the layout
 329                         // information when only edit
 330                         if (kind == Undo::EDIT) {
 331                                 tmppar2->clearContents();
 332                         }
 333                         tmppar2->next()->previous(tmppar2);
 334
 335                         tmppar2 = tmppar2->next();
 336                 }
 337                 tmppar2->next(0);
 338         } else
 339                 undopar = 0; // nothing to replace (undo of delete maybe)
 340
 341         int cursor_par = undoCursor(bv).par()->id();
 342         int cursor_pos =  undoCursor(bv).pos();
 343
 344         u.reset(new Undo(kind, inset_id,
 345                 before_number, behind_number,
 346                 cursor_par, cursor_pos, undopar));
 347
 348         undo_finished = false;
 349         return true;
 350 }
 351
 352 } // namespace anon
 353
 354 void finishUndo()
 355 {
 356         // makes sure the next operation will be stored
 357         undo_finished = true;
 358 }
 359
 360
 361 void freezeUndo()
 362 {
 363         // this is dangerous and for internal use only
 364         undo_frozen = true;
 365 }
 366
 367
 368 void unFreezeUndo()
 369 {
 370         // this is dangerous and for internal use only
 371         undo_frozen = false;
 372 }
 373
 374
 375 // returns false if no undo possible
 376 bool textUndo(BufferView * bv)
 377 {
 378         Buffer * b = bv->buffer();
 379
 380         if (b->undostack.empty()) {
 381                 finishNoUndo(bv);
 382                 return false;
 383         }
 384
 385         shared_ptr<Undo> undo = b->undostack.top();
 386         b->undostack.pop();
 387         finishUndo();
 388
 389         if (!undo_frozen) {
 390                 Paragraph * first = b->getParFromID(undo->number_of_before_par);
 391                 if (first && first->next())
 392                         first = first->next();
 393                 else if (!first)
 394                         first = firstUndoParagraph(bv, undo->number_of_inset_id);
 395                 if (first) {
 396                         shared_ptr<Undo> u;
 397                         if (createUndo(bv, undo->kind, first,
 398                                 b->getParFromID(undo->number_of_behind_par), u))
 399                                 b->redostack.push(u);
 400                 }
 401         }
 402
 403         // now we can unlock the inset for saftey because the inset pointer could
 404         // be changed during the undo-function. Anyway if needed we have to lock
 405         // the right inset/position if this is requested.
 406         freezeUndo();
 407         bv->unlockInset(bv->theLockingInset());
 408         bool const ret = textHandleUndo(bv, *undo.get());
 409         unFreezeUndo();
 410         return ret;
 411 }
 412
 413
 414 // returns false if no redo possible
 415 bool textRedo(BufferView * bv)
 416 {
 417         Buffer * b = bv->buffer();
 418
 419         if (b->redostack.empty()) {
 420                 finishNoUndo(bv);
 421                 return false;
 422         }
 423
 424         shared_ptr<Undo> undo = b->redostack.top();
 425         b->redostack.pop();
 426         finishUndo();
 427
 428         if (!undo_frozen) {
 429         Paragraph * first = bv->buffer()->getParFromID(undo->number_of_before_par);
 430                 if (first && first->next())
 431                         first = first->next();
 432                 else if (!first)
 433                         first = firstUndoParagraph(bv, undo->number_of_inset_id);
 434                 if (first) {
 435                         shared_ptr<Undo> u;
 436                         if (createUndo(bv, undo->kind, first,
 437                                 bv->buffer()->getParFromID(undo->number_of_behind_par), u))
 438                                 bv->buffer()->undostack.push(u);
 439                 }
 440         }
 441
 442         // now we can unlock the inset for saftey because the inset pointer could
 443         // be changed during the undo-function. Anyway if needed we have to lock
 444         // the right inset/position if this is requested.
 445         freezeUndo();
 446         bv->unlockInset(bv->theLockingInset());
 447         bool ret = textHandleUndo(bv, *undo.get());
 448         unFreezeUndo();
 449         return ret;
 450 }
 451
 452
 453 void setUndo(BufferView * bv, Undo::undo_kind kind,
 454              Paragraph const * first, Paragraph const * behind)
 455 {
 456         if (!undo_frozen) {
 457                 shared_ptr<Undo> u;
 458                 if (createUndo(bv, kind, first, behind, u))
 459                         bv->buffer()->undostack.push(u);
 460                 bv->buffer()->redostack.clear();
 461         }
 462 }
 463
 464
 465 void setRedo(BufferView * bv, Undo::undo_kind kind,
 466              Paragraph const * first, Paragraph const * behind)
 467 {
 468         shared_ptr<Undo> u;
 469         if (createUndo(bv, kind, first, behind, u))
 470                 bv->buffer()->redostack.push(u);
 471 }
 472
 473
 474 void setCursorParUndo(BufferView * bv)
 475 {
 476         setUndo(bv, Undo::FINISH, bv->text->cursor.par(),
 477                 bv->text->cursor.par()->next());
 478 }