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 /// the flag used by FinishUndo();
  25 bool undo_finished;
  26 /// a flag
  27 bool undo_frozen;
  28
  29
  30 bool textUndo(BufferView * bv)
  31 {
  32         // returns false if no undo possible
  33         Undo * undo = bv->buffer()->undostack.top();
  34         bv->buffer()->undostack.pop();
  35         if (undo) {
  36                 finishUndo();
  37                 if (!undo_frozen) {
  38                         Paragraph * first = bv->buffer()->getParFromID(undo->number_of_before_par);
  39                         if (first && first->next())
  40                                 first = first->next();
  41                         else if (!first)
  42                                 first = firstUndoParagraph(bv, undo->number_of_inset_id);
  43                         if (first) {
  44                                 bv->buffer()->redostack.push(
  45                                         createUndo(bv, undo->kind, first,
  46                                                    bv->buffer()->getParFromID(undo->number_of_behind_par)));
  47                         }
  48                 }
  49         }
  50         // now we can unlock the inset for saftey because the inset pointer could
  51         // be changed during the undo-function. Anyway if needed we have to lock
  52         // the right inset/position if this is requested.
  53         freezeUndo();
  54         bv->unlockInset(bv->theLockingInset());
  55         bool ret = textHandleUndo(bv, undo);
  56         unFreezeUndo();
  57         return ret;
  58 }
  59
  60
  61 bool textRedo(BufferView * bv)
  62 {
  63         // returns false if no redo possible
  64         Undo * undo = bv->buffer()->redostack.top();
  65         bv->buffer()->redostack.pop();
  66         if (undo) {
  67                 finishUndo();
  68                 if (!undo_frozen) {
  69                         Paragraph * first = bv->buffer()->getParFromID(undo->number_of_before_par);
  70                         if (first && first->next())
  71                                 first = first->next();
  72                         else if (!first)
  73                                 first = firstUndoParagraph(bv, undo->number_of_inset_id);
  74                         if (first) {
  75                                 bv->buffer()->undostack.push(
  76                                         createUndo(bv, undo->kind, first,
  77                                                    bv->buffer()->getParFromID(undo->number_of_behind_par)));
  78                         }
  79                 }
  80         }
  81         // now we can unlock the inset for saftey because the inset pointer could
  82         // be changed during the undo-function. Anyway if needed we have to lock
  83         // the right inset/position if this is requested.
  84         freezeUndo();
  85         bv->unlockInset(bv->theLockingInset());
  86         bool ret = textHandleUndo(bv, undo);
  87         unFreezeUndo();
  88         return ret;
  89 }
  90
  91
  92 bool textHandleUndo(BufferView * bv, Undo * undo)
  93 {
  94         // returns false if no undo possible
  95         bool result = false;
  96         if (undo) {
  97                 Paragraph * before =
  98                         bv->buffer()->getParFromID(undo->number_of_before_par);
  99                 Paragraph * behind =
 100                         bv->buffer()->getParFromID(undo->number_of_behind_par);
 101                 Paragraph * tmppar;
 102                 Paragraph * tmppar2;
 103                 Paragraph * tmppar5;
 104
 105                 // if there's no before take the beginning
 106                 // of the document for redoing
 107                 if (!before) {
 108                         LyXText * t = bv->text;
 109                         int num = undo->number_of_inset_id;
 110                         if (undo->number_of_inset_id >= 0) {
 111                                 Inset * in = bv->buffer()->getInsetFromID(num);
 112                                 if (in) {
 113                                         t = in->getLyXText(bv);
 114                                 } else {
 115                                         num = -1;
 116                                 }
 117                         }
 118                         t->setCursorIntern(bv, firstUndoParagraph(bv, num), 0);
 119                 }
 120
 121                 // replace the paragraphs with the undo informations
 122
 123                 Paragraph * tmppar3 = undo->par;
 124                 undo->par = 0;  // otherwise the undo destructor would
 125                                 // delete the paragraph
 126
 127                 // get last undo par
 128                 Paragraph * tmppar4 = tmppar3;
 129                 if (tmppar4) {
 130                         while (tmppar4->next())
 131                                 tmppar4 = tmppar4->next();
 132                 }
 133
 134                 // now remove the old text if there is any
 135                 if (before != behind || (!behind && !before)) {
 136                         if (before)
 137                                 tmppar5 = before->next();
 138                         else
 139                                 tmppar5 = firstUndoParagraph(bv, undo->number_of_inset_id);
 140                         tmppar2 = tmppar3;
 141                         while (tmppar5 && tmppar5 != behind) {
 142                                 tmppar = tmppar5;
 143                                 tmppar5 = tmppar5->next();
 144                                 // a memory optimization for edit:
 145                                 // Only layout information
 146                                 // is stored in the undo. So restore
 147                                 // the text informations.
 148                                 if (undo->kind == Undo::EDIT) {
 149                                         tmppar2->setContentsFromPar(tmppar);
 150                                         tmppar->clearContents();
 151                                         tmppar2 = tmppar2->next();
 152                                 }
 153                         }
 154                 }
 155
 156                 // put the new stuff in the list if there is one
 157                 if (tmppar3){
 158                         if (before)
 159                                 before->next(tmppar3);
 160                         else
 161                                 bv->text->ownerParagraph(tmppar3->id(),
 162                                                          tmppar3);
 163
 164                         tmppar3->previous(before);
 165                 } else {
 166                         // Do we really enter here ??? (Jug)
 167                         if (!before)
 168                                 bv->text->ownerParagraph(behind);
 169                 }
 170                 if (tmppar4) {
 171                         tmppar4->next(behind);
 172                         if (behind)
 173                                 behind->previous(tmppar4);
 174                 }
 175
 176
 177                 // Set the cursor for redoing
 178                 if (before) {
 179                         Inset * it = before->inInset();
 180                         if (it)
 181                                 it->getLyXText(bv)->setCursorIntern(bv, before, 0);
 182                         else
 183                                 bv->text->setCursorIntern(bv, before, 0);
 184                 }
 185
 186                 Paragraph * endpar = 0;
 187                 // calculate the endpar for redoing the paragraphs.
 188                 if (behind)
 189                         endpar = behind->next();
 190
 191                 tmppar = bv->buffer()->getParFromID(undo->number_of_cursor_par);
 192                 UpdatableInset* it = static_cast<UpdatableInset*>(tmppar3->inInset());
 193                 if (it) {
 194                         it->getLyXText(bv)->redoParagraphs(bv, it->getLyXText(bv)->cursor,
 195                                                            endpar);
 196                         LyXFont font;
 197                         it->update(bv, font, false);
 198                         // we now would have to rebreak the whole paragraph the undo-par
 199                         // was in. How we do it here is not really true. We would have to
 200                         // save this information in the undo-struct and then we could do
 201                         // the right rebreak. Here we only handle the case where this
 202                         // was in the actual paragraph, which not always is true.
 203                         bv->text->redoParagraphs(bv, bv->text->cursor,
 204                                                                          bv->text->cursor.par());
 205                         if (tmppar){
 206                                 it = static_cast<UpdatableInset*>(tmppar->inInset());
 207                                 it->edit(bv);
 208                                 it->getLyXText(bv)->setCursorIntern(bv, tmppar, undo->cursor_pos);
 209                                 it->getLyXText(bv)->updateCounters(bv, it->getLyXText(bv)->cursor.row());
 210                         }
 211                         bv->text->setCursorIntern(bv, bv->text->cursor.par(),
 212                                                                           bv->text->cursor.pos());
 213                 } else {
 214                         bv->text->redoParagraphs(bv, bv->text->cursor, endpar);
 215                         if (tmppar) {
 216                                 LyXText * t;
 217                                 Inset * it = tmppar->inInset();
 218                                 if (it)
 219                                         t = it->getLyXText(bv);
 220                                 else
 221                                         t = bv->text;
 222                                 t->setCursorIntern(bv, tmppar, undo->cursor_pos);
 223                                 t->updateCounters(bv, t->cursor.row());
 224                         }
 225                 }
 226                 result = true;
 227                 delete undo;
 228         }
 229         finishUndo();
 230         bv->text->status(bv, LyXText::NEED_MORE_REFRESH);
 231         return result;
 232 }
 233
 234
 235 void finishUndo()
 236 {
 237         // makes sure the next operation will be stored
 238         undo_finished = true;
 239 }
 240
 241
 242 void freezeUndo()
 243 {
 244         // this is dangerous and for internal use only
 245         undo_frozen = true;
 246 }
 247
 248
 249 void unFreezeUndo()
 250 {
 251         // this is dangerous and for internal use only
 252         undo_frozen = false;
 253 }
 254
 255
 256 void setUndo(BufferView * bv, Undo::undo_kind kind,
 257              Paragraph const * first, Paragraph const * behind)
 258 {
 259         if (!undo_frozen) {
 260                 bv->buffer()->undostack.push(createUndo(bv, kind, first, behind));
 261                 bv->buffer()->redostack.clear();
 262         }
 263 }
 264
 265
 266 void setRedo(BufferView * bv, Undo::undo_kind kind,
 267              Paragraph const * first, Paragraph const * behind)
 268 {
 269         bv->buffer()->redostack.push(createUndo(bv, kind, first, behind));
 270 }
 271
 272
 273 Undo * createUndo(BufferView * bv, Undo::undo_kind kind,
 274                   Paragraph const * first, Paragraph const * behind)
 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         // Undo::EDIT  and Undo::FINISH are
 290         // always finished. (no overlapping there)
 291         // overlapping only with insert and delete inside one paragraph:
 292         // Nobody wants all removed  character
 293         // appear one by one when undoing.
 294         // EDIT is special since only layout information, not the
 295         // contents of a paragaph are stored.
 296         if (!undo_finished && (kind != Undo::EDIT) && (kind != Undo::FINISH)){
 297                 // check wether storing is needed
 298                 if (!bv->buffer()->undostack.empty() &&
 299                     bv->buffer()->undostack.top()->kind == kind &&
 300                     bv->buffer()->undostack.top()->number_of_before_par == before_number &&
 301                     bv->buffer()->undostack.top()->number_of_behind_par == behind_number) {
 302                         // no undo needed
 303                         return 0;
 304                 }
 305         }
 306         // create a new Undo
 307         Paragraph * undopar;
 308
 309         Paragraph * start = const_cast<Paragraph *>(first);
 310         Paragraph * end = 0;
 311
 312         if (behind)
 313                 end = const_cast<Paragraph*>(behind->previous());
 314         else {
 315                 end = start;
 316                 while (end->next())
 317                         end = end->next();
 318         }
 319         if (start && end && (start != end->next()) &&
 320             ((before_number != behind_number) ||
 321                  ((before_number < 0) && (behind_number < 0))))
 322         {
 323                 Paragraph * tmppar = start;
 324                 Paragraph * tmppar2 = new Paragraph(*tmppar, true);
 325
 326                 // a memory optimization: Just store the layout information
 327                 // when only edit
 328                 if (kind == Undo::EDIT) {
 329                         tmppar2->clearContents();
 330                 }
 331
 332                 undopar = tmppar2;
 333
 334                 while (tmppar != end && tmppar->next()) {
 335                         tmppar = tmppar->next();
 336                         tmppar2->next(new Paragraph(*tmppar, true));
 337                         // a memory optimization: Just store the layout
 338                         // information when only edit
 339                         if (kind == Undo::EDIT) {
 340                                 tmppar2->clearContents();
 341                         }
 342                         tmppar2->next()->previous(tmppar2);
 343                         tmppar2 = tmppar2->next();
 344                 }
 345                 tmppar2->next(0);
 346         } else
 347                 undopar = 0; // nothing to replace (undo of delete maybe)
 348
 349         int cursor_par = undoCursor(bv).par()->id();
 350         int cursor_pos =  undoCursor(bv).pos();
 351
 352         Undo * undo = new Undo(kind, inset_id,
 353                                before_number, behind_number,
 354                                cursor_par, cursor_pos, undopar);
 355
 356         undo_finished = false;
 357         return undo;
 358 }
 359
 360
 361 void setCursorParUndo(BufferView * bv)
 362 {
 363         setUndo(bv, Undo::FINISH, bv->text->cursor.par(),
 364                 bv->text->cursor.par()->next());
 365 }
 366
 367
 368 Paragraph * firstUndoParagraph(BufferView * bv, int inset_id)
 369 {
 370         Inset * inset = bv->buffer()->getInsetFromID(inset_id);
 371         if (inset) {
 372                 Paragraph * result = inset->getFirstParagraph(0);
 373                 if (result)
 374                         return result;
 375         }
 376         return bv->text->ownerParagraph();
 377 }
 378
 379
 380 LyXCursor const & undoCursor(BufferView * bv)
 381 {
 382         if (bv->theLockingInset())
 383                 return bv->theLockingInset()->cursor(bv);
 384         return bv->text->cursor;
 385 }