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 bool textUndo(BufferView * bv)
  30 {
  31         // returns false if no undo possible
  32         Undo * undo = bv->buffer()->undostack.pop();
  33         if (undo) {
  34                 finishUndo();
  35                 if (!undo_frozen) {
  36                         Paragraph * first = bv->buffer()->getParFromID(undo->number_of_before_par);
  37                         if (!first)
  38                                 first = firstUndoParagraph(bv, undo->number_of_inset_id);
  39                         if (first) {
  40                                 bv->buffer()->redostack.push(
  41                                         createUndo(bv, undo->kind, first,
  42                                                    bv->buffer()->getParFromID(undo->number_of_behind_par)));
  43                         }
  44                 }
  45         }
  46         return textHandleUndo(bv, undo);
  47 }
  48
  49
  50 bool textRedo(BufferView * bv)
  51 {
  52         // returns false if no redo possible
  53         Undo * undo = bv->buffer()->redostack.pop();
  54         if (undo) {
  55                 finishUndo();
  56                 if (!undo_frozen) {
  57                         Paragraph * first = bv->buffer()->getParFromID(undo->number_of_before_par);
  58                         if (!first)
  59                                 first = firstUndoParagraph(bv, undo->number_of_inset_id);
  60                         if (first) {
  61                                 bv->buffer()->undostack.push(
  62                                         createUndo(bv, undo->kind, first,
  63                                                    bv->buffer()->getParFromID(undo->number_of_behind_par)));
  64                         }
  65                 }
  66         }
  67         return textHandleUndo(bv, undo);
  68 }
  69
  70
  71 bool textHandleUndo(BufferView * bv, Undo * undo)
  72 {
  73         // returns false if no undo possible
  74         bool result = false;
  75         if (undo) {
  76                 Paragraph * before =
  77                         bv->buffer()->getParFromID(undo->number_of_before_par);
  78                 Paragraph * behind =
  79                         bv->buffer()->getParFromID(undo->number_of_behind_par);
  80                 Paragraph * tmppar;
  81                 Paragraph * tmppar2;
  82                 Paragraph * endpar;
  83                 Paragraph * tmppar5;
  84
  85                 // if there's no before take the beginning
  86                 // of the document for redoing
  87                 if (!before) {
  88                         LyXText * t = bv->text;
  89                         int num = undo->number_of_inset_id;
  90                         if (undo->number_of_inset_id >= 0) {
  91                                 Inset * in = bv->buffer()->getInsetFromID(num);
  92                                 if (in) {
  93                                         t = in->getLyXText(bv);
  94                                 } else {
  95                                         num = -1;
  96                                 }
  97                         }
  98                         t->setCursorIntern(bv, firstUndoParagraph(bv, num), 0);
  99                 }
 100
 101                 // replace the paragraphs with the undo informations
 102
 103                 Paragraph * tmppar3 = undo->par;
 104                 undo->par = 0;  // otherwise the undo destructor would
 105                                 // delete the paragraph
 106
 107                 // get last undo par
 108                 Paragraph * tmppar4 = tmppar3;
 109                 if (tmppar4) {
 110                         while (tmppar4->next())
 111                                 tmppar4 = tmppar4->next();
 112                 }
 113
 114                 // now remove the old text if there is any
 115                 if (before != behind || (!behind && !before)) {
 116                         if (before)
 117                                 tmppar5 = before->next();
 118                         else
 119                                 tmppar5 = firstUndoParagraph(bv, undo->number_of_inset_id);
 120                         tmppar2 = tmppar3;
 121                         while (tmppar5 && tmppar5 != behind) {
 122                                 tmppar = tmppar5;
 123                                 tmppar5 = tmppar5->next();
 124                                 // a memory optimization for edit:
 125                                 // Only layout information
 126                                 // is stored in the undo. So restore
 127                                 // the text informations.
 128                                 if (undo->kind == Undo::EDIT) {
 129                                         tmppar2->setContentsFromPar(tmppar);
 130                                         tmppar2 = tmppar2->next();
 131                                 }
 132                                 delete tmppar;
 133                         }
 134                 }
 135
 136                 // put the new stuff in the list if there is one
 137                 if (tmppar3){
 138                         if (before)
 139                                 before->next(tmppar3);
 140                         else
 141 #warning Juergen, why is this needed?? (JMarc)
 142 // since tmppar3 is not yet inserted in the document, I do not see why
 143 // the getParFromID which is done by the function below makes sense.
 144 // OTOH, since you wrote the method just for this instance, I guess you
 145 // have something in mind
 146 #if 1
 147                                 bv->text->ownerParagraph(tmppar3->id(),
 148                                                          tmppar3);
 149 #else
 150 // in this case, since getParFromID is not called, the program does
 151 // not crash on trying to access buffer()->paragraph, which does not
 152 // exist anymore if we undid the first par f the document. (JMarc)
 153                                 bv->text->ownerParagraph(tmppar3);
 154 #endif
 155
 156                         tmppar3->previous(before);
 157                 } else {
 158                         // Do we really enter here ??? (Jug)
 159                         if (!before)
 160                                 bv->text->ownerParagraph(behind);
 161                 }
 162                 if (tmppar4) {
 163                         tmppar4->next(behind);
 164                         if (behind)
 165                                 behind->previous(tmppar4);
 166                 }
 167
 168
 169                 // Set the cursor for redoing
 170                 if (before) {
 171                         bv->text->setCursorIntern(bv, before, 0);
 172                 }
 173
 174                 // calculate the endpar for redoing the paragraphs.
 175                 if (behind) {
 176                                 endpar = behind->next();
 177                 } else
 178                         endpar = behind;
 179
 180                 tmppar = bv->buffer()->getParFromID(undo->number_of_cursor_par);
 181                 UpdatableInset* it = static_cast<UpdatableInset*>(tmppar3->inInset());
 182                 if (it) {
 183                         it->getLyXText(bv)->redoParagraphs(bv, it->getLyXText(bv)->cursor,
 184                                                            endpar);
 185                         if (tmppar){
 186                                 it->getLyXText(bv)->setCursorIntern(bv, tmppar, undo->cursor_pos);
 187                                 it->getLyXText(bv)->updateCounters(bv, it->getLyXText(bv)->cursor.row());
 188                         }
 189                         LyXFont font;
 190                         it->update(bv, font, false);
 191 #ifdef THIS_DOES_NOT_WORK
 192                         // we need this anyway as also if the undo was
 193                         // inside an inset we have to redo the
 194                         // paragraph breaking
 195                         bv->text->redoParagraphs(bv, bv->text->cursor,
 196                                                  bv->text->cursor.par());
 197 #endif
 198                 } else {
 199                         bv->text->redoParagraphs(bv, bv->text->cursor, endpar);
 200                         if (tmppar) {
 201                                 bv->text->setCursorIntern(bv, tmppar, undo->cursor_pos);
 202                                 bv->text->updateCounters(bv, bv->text->cursor.row());
 203                         }
 204                 }
 205                 result = true;
 206                 delete undo;
 207         }
 208         finishUndo();
 209         bv->text->status(bv, LyXText::NEED_MORE_REFRESH);
 210         return result;
 211 }
 212
 213
 214 void finishUndo()
 215 {
 216         // makes sure the next operation will be stored
 217         undo_finished = true;
 218 }
 219
 220
 221 void freezeUndo()
 222 {
 223         // this is dangerous and for internal use only
 224         undo_frozen = true;
 225 }
 226
 227
 228 void unFreezeUndo()
 229 {
 230         // this is dangerous and for internal use only
 231         undo_frozen = false;
 232 }
 233
 234
 235 void setUndo(BufferView * bv, Undo::undo_kind kind,
 236              Paragraph const * first, Paragraph const * behind)
 237 {
 238         if (!undo_frozen)
 239                 bv->buffer()->undostack.push(createUndo(bv, kind, first, behind));
 240         bv->buffer()->redostack.clear();
 241 }
 242
 243
 244 void setRedo(BufferView * bv, Undo::undo_kind kind,
 245              Paragraph const * first, Paragraph const * behind)
 246 {
 247         bv->buffer()->redostack.push(createUndo(bv, kind, first, behind));
 248 }
 249
 250 using lyx::pos_type;
 251
 252 Undo * createUndo(BufferView * bv, Undo::undo_kind kind,
 253                   Paragraph const * first, Paragraph const * behind)
 254 {
 255         lyx::Assert(first);
 256
 257         int before_number = -1;
 258         int behind_number = -1;
 259         int inset_id = -1;
 260
 261         if (first->previous())
 262                 before_number = first->previous()->id();
 263         if (behind)
 264                 behind_number = behind->id();
 265         if (first->inInset())
 266                 inset_id = first->inInset()->id();
 267
 268         // Undo::EDIT  and Undo::FINISH are
 269         // always finished. (no overlapping there)
 270         // overlapping only with insert and delete inside one paragraph:
 271         // Nobody wants all removed  character
 272         // appear one by one when undoing.
 273         // EDIT is special since only layout information, not the
 274         // contents of a paragaph are stored.
 275         if (!undo_finished && (kind != Undo::EDIT) && (kind != Undo::FINISH)){
 276                 // check wether storing is needed
 277                 if (!bv->buffer()->undostack.empty() &&
 278                     bv->buffer()->undostack.top()->kind == kind &&
 279                     bv->buffer()->undostack.top()->number_of_before_par ==  before_number &&
 280                     bv->buffer()->undostack.top()->number_of_behind_par ==  behind_number ){
 281                         // no undo needed
 282                         return 0;
 283                 }
 284         }
 285         // create a new Undo
 286         Paragraph * undopar;
 287
 288         Paragraph * start = const_cast<Paragraph *>(first);
 289         Paragraph * end = 0;
 290
 291         if (behind)
 292                 end = const_cast<Paragraph*>(behind->previous());
 293         else {
 294                 end = start;
 295                 while (end->next())
 296                         end = end->next();
 297         }
 298         if (start && end && (start != end->next()) &&
 299             ((before_number != behind_number) ||
 300                  ((before_number < 0) && (behind_number < 0)))) {
 301                 Paragraph * tmppar = start;
 302                 Paragraph * tmppar2 = new Paragraph(*tmppar, true);
 303                 tmppar2->id(tmppar->id());
 304
 305                 // a memory optimization: Just store the layout information
 306                 // when only edit
 307                 if (kind == Undo::EDIT) {
 308                         tmppar2->clearContents();
 309                 }
 310
 311                 undopar = tmppar2;
 312
 313                 while (tmppar != end && tmppar->next()) {
 314                         tmppar = tmppar->next();
 315                         tmppar2->next(new Paragraph(*tmppar, false));
 316                         tmppar2->next()->id(tmppar->id());
 317                         // a memory optimization: Just store the layout
 318                         // information when only edit
 319                         if (kind == Undo::EDIT) {
 320                                 tmppar2->clearContents();
 321                         }
 322                         tmppar2->next()->previous(tmppar2);
 323                         tmppar2 = tmppar2->next();
 324                 }
 325                 tmppar2->next(0);
 326         } else
 327                 undopar = 0; // nothing to replace (undo of delete maybe)
 328
 329         int cursor_par = undoCursor(bv).par()->id();
 330         int cursor_pos =  undoCursor(bv).pos();
 331
 332         Undo * undo = new Undo(kind, inset_id,
 333                                before_number, behind_number,
 334                                cursor_par, cursor_pos, undopar);
 335
 336         undo_finished = false;
 337         return undo;
 338 }
 339
 340
 341 void setCursorParUndo(BufferView * bv)
 342 {
 343         setUndo(bv, Undo::FINISH,
 344                 bv->text->cursor.par(),
 345                         bv->text->cursor.par()->next());
 346 }
 347
 348 Paragraph * firstUndoParagraph(BufferView * bv, int inset_id)
 349 {
 350         Inset * inset = bv->buffer()->getInsetFromID(inset_id);
 351         if (inset) {
 352                 Paragraph * result = inset->firstParagraph();
 353                 if (result)
 354                         return result;
 355         }
 356         return bv->text->ownerParagraph();
 357 }
 358
 359 LyXCursor const & undoCursor(BufferView * bv)
 360 {
 361         if (bv->theLockingInset())
 362                 return bv->theLockingInset()->cursor(bv);
 363         return bv->text->cursor;
 364 }