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)
  40                                 first = firstUndoParagraph(bv, undo->number_of_inset_id);
  41                         if (first) {
  42                                 bv->buffer()->redostack.push(
  43                                         createUndo(bv, undo->kind, first,
  44                                                    bv->buffer()->getParFromID(undo->number_of_behind_par)));
  45                         }
  46                 }
  47         }
  48         return textHandleUndo(bv, undo);
  49 }
  50
  51
  52 bool textRedo(BufferView * bv)
  53 {
  54         // returns false if no redo possible
  55         Undo * undo = bv->buffer()->redostack.top();
  56         bv->buffer()->redostack.pop();
  57         if (undo) {
  58                 finishUndo();
  59                 if (!undo_frozen) {
  60                         Paragraph * first = bv->buffer()->getParFromID(undo->number_of_before_par);
  61                         if (!first)
  62                                 first = firstUndoParagraph(bv, undo->number_of_inset_id);
  63                         if (first) {
  64                                 bv->buffer()->undostack.push(
  65                                         createUndo(bv, undo->kind, first,
  66                                                    bv->buffer()->getParFromID(undo->number_of_behind_par)));
  67                         }
  68                 }
  69         }
  70         return textHandleUndo(bv, undo);
  71 }
  72
  73
  74 bool textHandleUndo(BufferView * bv, Undo * undo)
  75 {
  76         // returns false if no undo possible
  77         bool result = false;
  78         if (undo) {
  79                 Paragraph * before =
  80                         bv->buffer()->getParFromID(undo->number_of_before_par);
  81                 Paragraph * behind =
  82                         bv->buffer()->getParFromID(undo->number_of_behind_par);
  83                 Paragraph * tmppar;
  84                 Paragraph * tmppar2;
  85                 Paragraph * endpar;
  86                 Paragraph * tmppar5;
  87
  88                 // if there's no before take the beginning
  89                 // of the document for redoing
  90                 if (!before) {
  91                         LyXText * t = bv->text;
  92                         int num = undo->number_of_inset_id;
  93                         if (undo->number_of_inset_id >= 0) {
  94                                 Inset * in = bv->buffer()->getInsetFromID(num);
  95                                 if (in) {
  96                                         t = in->getLyXText(bv);
  97                                 } else {
  98                                         num = -1;
  99                                 }
 100                         }
 101                         t->setCursorIntern(bv, firstUndoParagraph(bv, num), 0);
 102                 }
 103
 104                 // replace the paragraphs with the undo informations
 105
 106                 Paragraph * tmppar3 = undo->par;
 107                 undo->par = 0;  // otherwise the undo destructor would
 108                                 // delete the paragraph
 109
 110                 // get last undo par
 111                 Paragraph * tmppar4 = tmppar3;
 112                 if (tmppar4) {
 113                         while (tmppar4->next())
 114                                 tmppar4 = tmppar4->next();
 115                 }
 116
 117                 // now remove the old text if there is any
 118                 if (before != behind || (!behind && !before)) {
 119                         if (before)
 120                                 tmppar5 = before->next();
 121                         else
 122                                 tmppar5 = firstUndoParagraph(bv, undo->number_of_inset_id);
 123                         tmppar2 = tmppar3;
 124                         while (tmppar5 && tmppar5 != behind) {
 125                                 tmppar = tmppar5;
 126                                 tmppar5 = tmppar5->next();
 127                                 // a memory optimization for edit:
 128                                 // Only layout information
 129                                 // is stored in the undo. So restore
 130                                 // the text informations.
 131                                 if (undo->kind == Undo::EDIT) {
 132                                         tmppar2->setContentsFromPar(tmppar);
 133                                         tmppar2 = tmppar2->next();
 134                                 }
 135                                 delete tmppar;
 136                         }
 137                 }
 138
 139                 // put the new stuff in the list if there is one
 140                 if (tmppar3){
 141                         if (before)
 142                                 before->next(tmppar3);
 143                         else
 144 #warning Juergen, why is this needed?? (JMarc)
 145 // since tmppar3 is not yet inserted in the document, I do not see why
 146 // the getParFromID which is done by the function below makes sense.
 147 // OTOH, since you wrote the method just for this instance, I guess you
 148 // have something in mind
 149 #if 1
 150                                 bv->text->ownerParagraph(tmppar3->id(),
 151                                                          tmppar3);
 152 #else
 153 // in this case, since getParFromID is not called, the program does
 154 // not crash on trying to access buffer()->paragraph, which does not
 155 // exist anymore if we undid the first par f the document. (JMarc)
 156                                 bv->text->ownerParagraph(tmppar3);
 157 #endif
 158
 159                         tmppar3->previous(before);
 160                 } else {
 161                         // Do we really enter here ??? (Jug)
 162                         if (!before)
 163                                 bv->text->ownerParagraph(behind);
 164                 }
 165                 if (tmppar4) {
 166                         tmppar4->next(behind);
 167                         if (behind)
 168                                 behind->previous(tmppar4);
 169                 }
 170
 171
 172                 // Set the cursor for redoing
 173                 if (before) {
 174                         bv->text->setCursorIntern(bv, before, 0);
 175                 }
 176
 177                 // calculate the endpar for redoing the paragraphs.
 178                 if (behind) {
 179                                 endpar = behind->next();
 180                 } else
 181                         endpar = behind;
 182
 183                 tmppar = bv->buffer()->getParFromID(undo->number_of_cursor_par);
 184                 UpdatableInset* it = static_cast<UpdatableInset*>(tmppar3->inInset());
 185                 if (it) {
 186                         it->getLyXText(bv)->redoParagraphs(bv, it->getLyXText(bv)->cursor,
 187                                                            endpar);
 188                         if (tmppar){
 189                                 it->getLyXText(bv)->setCursorIntern(bv, tmppar, undo->cursor_pos);
 190                                 it->getLyXText(bv)->updateCounters(bv, it->getLyXText(bv)->cursor.row());
 191                         }
 192                         LyXFont font;
 193                         it->update(bv, font, false);
 194 #ifdef THIS_DOES_NOT_WORK
 195                         // we need this anyway as also if the undo was
 196                         // inside an inset we have to redo the
 197                         // paragraph breaking
 198                         bv->text->redoParagraphs(bv, bv->text->cursor,
 199                                                  bv->text->cursor.par());
 200 #endif
 201                 } else {
 202                         bv->text->redoParagraphs(bv, bv->text->cursor, endpar);
 203                         if (tmppar) {
 204                                 bv->text->setCursorIntern(bv, tmppar, undo->cursor_pos);
 205                                 bv->text->updateCounters(bv, bv->text->cursor.row());
 206                         }
 207                 }
 208                 result = true;
 209                 delete undo;
 210         }
 211         finishUndo();
 212         bv->text->status(bv, LyXText::NEED_MORE_REFRESH);
 213         return result;
 214 }
 215
 216
 217 void finishUndo()
 218 {
 219         // makes sure the next operation will be stored
 220         undo_finished = true;
 221 }
 222
 223
 224 void freezeUndo()
 225 {
 226         // this is dangerous and for internal use only
 227         undo_frozen = true;
 228 }
 229
 230
 231 void unFreezeUndo()
 232 {
 233         // this is dangerous and for internal use only
 234         undo_frozen = false;
 235 }
 236
 237
 238 void setUndo(BufferView * bv, Undo::undo_kind kind,
 239              Paragraph const * first, Paragraph const * behind)
 240 {
 241         if (!undo_frozen)
 242                 bv->buffer()->undostack.push(createUndo(bv, kind, first, behind));
 243         bv->buffer()->redostack.clear();
 244 }
 245
 246
 247 void setRedo(BufferView * bv, Undo::undo_kind kind,
 248              Paragraph const * first, Paragraph const * behind)
 249 {
 250         bv->buffer()->redostack.push(createUndo(bv, kind, first, behind));
 251 }
 252
 253
 254 Undo * createUndo(BufferView * bv, Undo::undo_kind kind,
 255                   Paragraph const * first, Paragraph const * behind)
 256 {
 257         lyx::Assert(first);
 258
 259         int before_number = -1;
 260         int behind_number = -1;
 261         int inset_id = -1;
 262
 263         if (first->previous())
 264                 before_number = first->previous()->id();
 265         if (behind)
 266                 behind_number = behind->id();
 267         if (first->inInset())
 268                 inset_id = first->inInset()->id();
 269
 270         // Undo::EDIT  and Undo::FINISH are
 271         // always finished. (no overlapping there)
 272         // overlapping only with insert and delete inside one paragraph:
 273         // Nobody wants all removed  character
 274         // appear one by one when undoing.
 275         // EDIT is special since only layout information, not the
 276         // contents of a paragaph are stored.
 277         if (!undo_finished && (kind != Undo::EDIT) && (kind != Undo::FINISH)){
 278                 // check wether storing is needed
 279                 if (!bv->buffer()->undostack.empty() &&
 280                     bv->buffer()->undostack.top()->kind == kind &&
 281                     bv->buffer()->undostack.top()->number_of_before_par == before_number &&
 282                     bv->buffer()->undostack.top()->number_of_behind_par == behind_number) {
 283                         // no undo needed
 284                         return 0;
 285                 }
 286         }
 287         // create a new Undo
 288         Paragraph * undopar;
 289
 290         Paragraph * start = const_cast<Paragraph *>(first);
 291         Paragraph * end = 0;
 292
 293         if (behind)
 294                 end = const_cast<Paragraph*>(behind->previous());
 295         else {
 296                 end = start;
 297                 while (end->next())
 298                         end = end->next();
 299         }
 300         if (start && end && (start != end->next()) &&
 301             ((before_number != behind_number) ||
 302                  ((before_number < 0) && (behind_number < 0)))) {
 303                 Paragraph * tmppar = start;
 304                 Paragraph * tmppar2 = new Paragraph(*tmppar, true);
 305                 tmppar2->id(tmppar->id());
 306
 307                 // a memory optimization: Just store the layout information
 308                 // when only edit
 309                 if (kind == Undo::EDIT) {
 310                         tmppar2->clearContents();
 311                 }
 312
 313                 undopar = tmppar2;
 314
 315                 while (tmppar != end && tmppar->next()) {
 316                         tmppar = tmppar->next();
 317                         tmppar2->next(new Paragraph(*tmppar, false));
 318                         tmppar2->next()->id(tmppar->id());
 319                         // a memory optimization: Just store the layout
 320                         // information when only edit
 321                         if (kind == Undo::EDIT) {
 322                                 tmppar2->clearContents();
 323                         }
 324                         tmppar2->next()->previous(tmppar2);
 325                         tmppar2 = tmppar2->next();
 326                 }
 327                 tmppar2->next(0);
 328         } else
 329                 undopar = 0; // nothing to replace (undo of delete maybe)
 330
 331         int cursor_par = undoCursor(bv).par()->id();
 332         int cursor_pos =  undoCursor(bv).pos();
 333
 334         Undo * undo = new Undo(kind, inset_id,
 335                                before_number, behind_number,
 336                                cursor_par, cursor_pos, undopar);
 337
 338         undo_finished = false;
 339         return undo;
 340 }
 341
 342
 343 void setCursorParUndo(BufferView * bv)
 344 {
 345         setUndo(bv, Undo::FINISH,
 346                 bv->text->cursor.par(),
 347                         bv->text->cursor.par()->next());
 348 }
 349
 350
 351 Paragraph * firstUndoParagraph(BufferView * bv, int inset_id)
 352 {
 353         Inset * inset = bv->buffer()->getInsetFromID(inset_id);
 354         if (inset) {
 355                 Paragraph * result = inset->firstParagraph();
 356                 if (result)
 357                         return result;
 358         }
 359         return bv->text->ownerParagraph();
 360 }
 361
 362
 363 LyXCursor const & undoCursor(BufferView * bv)
 364 {
 365         if (bv->theLockingInset())
 366                 return bv->theLockingInset()->cursor(bv);
 367         return bv->text->cursor;
 368 }