src/undo.C

   1 /**
   2  * \file undo.C
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Asger Alstrup
   7  * \author Lars Gullik Bjønnes
   8  * \author John Levon
   9  * \author André Pönitz
  10  * \author Jürgen Vigna
  11  *
  12  * Full author contact details are available in file CREDITS.
  13  */
  14
  15 #include <config.h>
  16
  17 #include "undo.h"
  18
  19 #include "buffer.h"
  20 #include "debug.h"
  21 #include "BufferView.h"
  22 #include "iterators.h"
  23 #include "lyxtext.h"
  24 #include "paragraph.h"
  25
  26 using lyx::paroffset_type;
  27
  28
  29 /// The flag used by finishUndo().
  30 bool undo_finished;
  31
  32 /// Whether actions are not added to the undo stacks.
  33 bool undo_frozen;
  34
  35 Undo::Undo(undo_kind kind_, int text_, int index_,
  36            int first_par_, int end_par_, int cursor_par_, int cursor_pos_)
  37         :
  38                 kind(kind_),
  39                 text(text_),
  40                 index(index_),
  41                 first_par(first_par_),
  42                 end_par(end_par_),
  43                 cursor_par(cursor_par_),
  44                 cursor_pos(cursor_pos_)
  45 {}
  46
  47
  48 namespace {
  49
  50 std::ostream & operator<<(std::ostream & os, Undo const & undo)
  51 {
  52         return os << " text: " << undo.text
  53                 << " index: " << undo.index
  54                 << " first: " << undo.first_par
  55                 << " from end: " << undo.end_par
  56                 << " cursor: " << undo.cursor_par
  57                 << "/" << undo.cursor_pos;
  58 }
  59
  60
  61 // translates LyXText pointer into offset count from document begin
  62 ParIterator text2pit(LyXText * text, int & tcount)
  63 {
  64         tcount = 0;
  65         Buffer * buf = text->bv()->buffer();
  66         ParIterator pit = buf->par_iterator_begin();
  67         ParIterator end = buf->par_iterator_end();
  68
  69         // it.text() returns 0 for outermost text.
  70         if (text == text->bv()->text)
  71                 return pit;
  72
  73         for ( ; pit != end; ++pit, ++tcount)
  74                 if (pit.text() == text)
  75                         return pit;
  76         lyxerr << "undo: should not happen" << std::endl;
  77         return end;
  78 }
  79
  80
  81 // translates offset from buffer begin to ParIterator
  82 ParIterator num2pit(BufferView * bv, int num)
  83 {
  84         Buffer * buf = bv->buffer();
  85         ParIterator pit = buf->par_iterator_begin();
  86         ParIterator end = buf->par_iterator_end();
  87
  88         for ( ; num && pit != end; ++pit, --num)
  89                 ;
  90
  91         if (pit != end)
  92                 return pit;
  93
  94         // don't crash early...
  95         lyxerr << "undo: num2pit: num: " << num << std::endl;
  96         BOOST_ASSERT(false);
  97         return buf->par_iterator_begin();
  98 }
  99
 100
 101 // translates offset from buffer begin to LyXText
 102 LyXText * pit2text(BufferView * bv, ParIterator const & pit)
 103 {
 104         LyXText * text = pit.text();
 105         return text ? text : bv->text;
 106 }
 107
 108
 109 void recordUndo(Undo::undo_kind kind,
 110         LyXText * text, paroffset_type first_par, paroffset_type last_par,
 111         limited_stack<Undo> & stack)
 112 {
 113         Buffer * buf = text->bv()->buffer();
 114
 115         int const end_par = text->ownerParagraphs().size() - last_par;
 116
 117         // Undo::ATOMIC are always recorded (no overlapping there).
 118         // overlapping only with insert and delete inside one paragraph:
 119         // nobody wants all removed character appear one by one when undoing.
 120         if (!undo_finished && kind != Undo::ATOMIC) {
 121                 // Check whether storing is needed.
 122                 if (!buf->undostack().empty()
 123                     && buf->undostack().top().kind == kind
 124                     && buf->undostack().top().first_par == first_par
 125                     && buf->undostack().top().end_par == end_par) {
 126                         // No additonal undo recording needed -
 127                         // effectively, we combine undo recordings to one.
 128                         return;
 129                 }
 130         }
 131
 132         // make and push the Undo entry
 133         int textnum;
 134         ParIterator pit = text2pit(text, textnum);
 135         stack.push(Undo(kind, textnum, pit.index(),
 136                 first_par, end_par, text->cursor.par(), text->cursor.pos()));
 137         lyxerr << "undo record: " << stack.top() << std::endl;
 138
 139         // record the relevant paragraphs
 140         ParagraphList & undo_pars = stack.top().pars;
 141
 142         ParagraphList & plist = text->ownerParagraphs();
 143         ParagraphList::iterator first = plist.begin();
 144         advance(first, first_par);
 145         ParagraphList::iterator last = plist.begin();
 146         advance(last, last_par);
 147
 148         for (ParagraphList::iterator it = first; it != last; ++it) {
 149                 undo_pars.push_back(*it);
 150                 undo_pars.back().id(it->id());
 151         }
 152         undo_pars.push_back(*last);
 153         undo_pars.back().id(last->id());
 154
 155         // and make sure that next time, we should be combining if possible
 156         undo_finished = false;
 157 }
 158
 159
 160 // returns false if no undo possible
 161 bool performUndoOrRedo(BufferView * bv, Undo const & undo)
 162 {
 163         lyxerr << "undo, performing: " << undo << std::endl;
 164         ParIterator pit = num2pit(bv, undo.text);
 165         LyXText * text = pit2text(bv, pit);
 166         ParagraphList & plist = text->ownerParagraphs();
 167
 168         // remove new stuff between first and last
 169         {
 170                 ParagraphList::iterator first = plist.begin();
 171                 advance(first, undo.first_par);
 172                 ParagraphList::iterator last = plist.begin();
 173                 advance(last, plist.size() - undo.end_par);
 174                 plist.erase(first, ++last);
 175         }
 176
 177         // re-insert old stuff instead
 178         if (plist.empty()) {
 179                 plist.assign(undo.pars.begin(), undo.pars.end());
 180         } else {
 181                 ParagraphList::iterator first = plist.begin();
 182                 advance(first, undo.first_par);
 183                 plist.insert(first, undo.pars.begin(), undo.pars.end());
 184         }
 185
 186         // set cursor
 187         lyxerr <<   "undo, text: " << undo.text
 188                 << " inset: " << pit.inset()
 189                 << " index: " << undo.index
 190                 << std::endl;
 191         InsetOld * inset = pit.inset();
 192         if (inset) {
 193                 // magic needed to cope with inset locking
 194                 inset->edit(bv, undo.index);
 195         }
 196
 197         // set cursor again to force the position to be the right one
 198         text->setCursorIntern(undo.cursor_par, undo.cursor_pos);
 199
 200         // clear any selection
 201         text->clearSelection();
 202         text->selection.cursor = text->cursor;
 203         text->updateCounters();
 204
 205         // rebreak the entire document
 206         bv->text->fullRebreak();
 207
 208         finishUndo();
 209         return true;
 210 }
 211
 212
 213 // returns false if no undo possible
 214 bool textUndoOrRedo(BufferView * bv,
 215         limited_stack<Undo> & stack, limited_stack<Undo> & otherstack)
 216 {
 217         if (stack.empty()) {
 218                 // nothing to do
 219                 freezeUndo();
 220                 bv->unlockInset(bv->theLockingInset());
 221                 finishUndo();
 222                 unFreezeUndo();
 223                 return false;
 224         }
 225
 226         Undo undo = stack.top();
 227         stack.pop();
 228         finishUndo();
 229
 230         if (!undo_frozen) {
 231                 otherstack.push(undo);
 232                 otherstack.top().pars.clear();
 233                 ParIterator pit = num2pit(bv, undo.text);
 234                 ParagraphList & plist = pit.plist();
 235                 if (undo.first_par + undo.end_par <= int(plist.size())) {
 236                         ParagraphList::iterator first = plist.begin();
 237                         advance(first, undo.first_par);
 238                         ParagraphList::iterator last = plist.begin();
 239                         advance(last, plist.size() - undo.end_par + 1);
 240                         otherstack.top().pars.insert(otherstack.top().pars.begin(), first, last);
 241                 }
 242                 LyXText * text = pit2text(bv, pit);
 243                 otherstack.top().cursor_pos = text->cursor.pos();
 244                 otherstack.top().cursor_par = text->cursor.par();
 245                 lyxerr << " undo other: " << otherstack.top() << std::endl;
 246         }
 247
 248         // Now we can unlock the inset for safety because the inset
 249         // pointer could be changed during the undo-function. Anyway
 250         // if needed we have to lock the right inset/position if this
 251         // is requested.
 252         freezeUndo();
 253         bv->unlockInset(bv->theLockingInset());
 254         bool const ret = performUndoOrRedo(bv, undo);
 255         unFreezeUndo();
 256         return ret;
 257 }
 258
 259 } // namespace anon
 260
 261
 262 void freezeUndo()
 263 {
 264         // this is dangerous and for internal use only
 265         undo_frozen = true;
 266 }
 267
 268
 269 void unFreezeUndo()
 270 {
 271         // this is dangerous and for internal use only
 272         undo_frozen = false;
 273 }
 274
 275
 276 void finishUndo()
 277 {
 278         // makes sure the next operation will be stored
 279         undo_finished = true;
 280 }
 281
 282
 283 bool textUndo(BufferView * bv)
 284 {
 285         return textUndoOrRedo(bv, bv->buffer()->undostack(),
 286                               bv->buffer()->redostack());
 287 }
 288
 289
 290 bool textRedo(BufferView * bv)
 291 {
 292         return textUndoOrRedo(bv, bv->buffer()->redostack(),
 293                               bv->buffer()->undostack());
 294 }
 295
 296
 297 void recordUndo(Undo::undo_kind kind,
 298         LyXText const * text, paroffset_type first, paroffset_type last)
 299 {
 300         if (undo_frozen)
 301                 return;
 302         Buffer * buf = text->bv()->buffer();
 303         recordUndo(kind, const_cast<LyXText *>(text), first, last, buf->undostack());
 304         buf->redostack().clear();
 305 }
 306
 307
 308 void recordUndo(Undo::undo_kind kind, LyXText const * text, paroffset_type par)
 309 {
 310         recordUndo(kind, text, par, par);
 311 }
 312
 313
 314 void recordUndo(BufferView * bv, Undo::undo_kind kind)
 315 {
 316         recordUndo(kind, bv->text, bv->text->cursor.par());
 317 }