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 #include "insets/updatableinset.h" // for dynamic_cast<UpdatableInset *>
  27
  28 using lyx::paroffset_type;
  29
  30
  31 /// The flag used by finishUndo().
  32 bool undo_finished;
  33
  34 /// Whether actions are not added to the undo stacks.
  35 bool undo_frozen;
  36
  37 Undo::Undo(undo_kind kind_, int text_, int index_,
  38            int first_par_, int end_par_, int cursor_par_, int cursor_pos_)
  39         :
  40                 kind(kind_),
  41                 text(text_),
  42                 index(index_),
  43                 first_par(first_par_),
  44                 end_par(end_par_),
  45                 cursor_par(cursor_par_),
  46                 cursor_pos(cursor_pos_)
  47 {}
  48
  49
  50 namespace {
  51
  52 std::ostream & operator<<(std::ostream & os, Undo const & undo)
  53 {
  54         return os << " text: " << undo.text
  55                 << " index: " << undo.index
  56                 << " first: " << undo.first_par
  57                 << " from end: " << undo.end_par
  58                 << " cursor: " << undo.cursor_par
  59                 << "/" << undo.cursor_pos;
  60 }
  61
  62
  63 // translates LyXText pointer into offset count from document begin
  64 ParIterator text2pit(LyXText * text, int & tcount)
  65 {
  66         tcount = 0;
  67         Buffer * buf = text->bv()->buffer();
  68         ParIterator pit = buf->par_iterator_begin();
  69         ParIterator end = buf->par_iterator_end();
  70
  71         // it.text() returns 0 for outermost text.
  72         if (text == text->bv()->text)
  73                 return pit;
  74
  75         for ( ; pit != end; ++pit, ++tcount)
  76                 if (pit.text() == text)
  77                         return pit;
  78         lyxerr << "undo: should not happen" << std::endl;
  79         return end;
  80 }
  81
  82
  83 // translates offset from buffer begin to ParIterator
  84 ParIterator num2pit(BufferView * bv, int num)
  85 {
  86         Buffer * buf = bv->buffer();
  87         ParIterator pit = buf->par_iterator_begin();
  88         ParIterator end = buf->par_iterator_end();
  89
  90         for ( ; num && pit != end; ++pit, --num)
  91                 ;
  92
  93         if (pit != end)
  94                 return pit;
  95
  96         // don't crash early...
  97         lyxerr << "undo: num2pit: num: " << num << std::endl;
  98         BOOST_ASSERT(false);
  99         return buf->par_iterator_begin();
 100 }
 101
 102
 103 // translates offset from buffer begin to LyXText
 104 LyXText * pit2text(BufferView * bv, ParIterator const & pit)
 105 {
 106         LyXText * text = pit.text();
 107         return text ? text : bv->text;
 108 }
 109
 110
 111 void recordUndo(Undo::undo_kind kind,
 112         LyXText * text, paroffset_type first_par, paroffset_type last_par,
 113         limited_stack<Undo> & stack)
 114 {
 115         Buffer * buf = text->bv()->buffer();
 116
 117         int const end_par = text->ownerParagraphs().size() - last_par;
 118
 119         // Undo::ATOMIC are always recorded (no overlapping there).
 120         // overlapping only with insert and delete inside one paragraph:
 121         // nobody wants all removed character appear one by one when undoing.
 122         if (!undo_finished && kind != Undo::ATOMIC) {
 123                 // Check whether storing is needed.
 124                 if (!buf->undostack().empty()
 125                     && buf->undostack().top().kind == kind
 126                     && buf->undostack().top().first_par == first_par
 127                     && buf->undostack().top().end_par == end_par) {
 128                         // No additonal undo recording needed -
 129                         // effectively, we combine undo recordings to one.
 130                         return;
 131                 }
 132         }
 133
 134         // make and push the Undo entry
 135         int textnum;
 136         ParIterator pit = text2pit(text, textnum);
 137         stack.push(Undo(kind, textnum, pit.index(),
 138                 first_par, end_par, text->cursor.par(), text->cursor.pos()));
 139         lyxerr << "undo record: " << stack.top() << std::endl;
 140
 141         // record the relevant paragraphs
 142         ParagraphList & undo_pars = stack.top().pars;
 143
 144         ParagraphList & plist = text->ownerParagraphs();
 145         ParagraphList::iterator first = plist.begin();
 146         advance(first, first_par);
 147         ParagraphList::iterator last = plist.begin();
 148         advance(last, last_par);
 149
 150         for (ParagraphList::iterator it = first; it != last; ++it)
 151                 undo_pars.push_back(*it);
 152         undo_pars.push_back(*last);
 153
 154         // and make sure that next time, we should be combining if possible
 155         undo_finished = false;
 156 }
 157
 158
 159 // returns false if no undo possible
 160 bool performUndoOrRedo(BufferView * bv, Undo const & undo)
 161 {
 162         lyxerr << "undo, performing: " << undo << std::endl;
 163         ParIterator pit = num2pit(bv, undo.text);
 164         LyXText * text = pit2text(bv, pit);
 165         ParagraphList & plist = text->ownerParagraphs();
 166
 167         // remove new stuff between first and last
 168         {
 169                 ParagraphList::iterator first = plist.begin();
 170                 advance(first, undo.first_par);
 171                 ParagraphList::iterator last = plist.begin();
 172                 advance(last, plist.size() - undo.end_par);
 173                 plist.erase(first, ++last);
 174         }
 175
 176         // re-insert old stuff instead
 177         if (plist.empty()) {
 178                 plist.assign(undo.pars.begin(), undo.pars.end());
 179         } else {
 180                 ParagraphList::iterator first = plist.begin();
 181                 advance(first, undo.first_par);
 182                 plist.insert(first, undo.pars.begin(), undo.pars.end());
 183         }
 184
 185         // set cursor
 186         lyxerr <<   "undo, text: " << undo.text
 187                 << " inset: " << pit.inset()
 188                 << " index: " << undo.index
 189                 << std::endl;
 190
 191         // set cursor again to force the position to be the right one
 192         text->cursor.par(undo.cursor_par);
 193         text->cursor.pos(undo.cursor_pos);
 194
 195         // clear any selection
 196         text->clearSelection();
 197         text->selection.cursor = text->cursor;
 198         text->updateCounters();
 199
 200         // rebreak the entire lyxtext
 201         bv->text->fullRebreak();
 202
 203         InsetOld * inset = pit.inset();
 204         if (inset) {
 205                 // magic needed to cope with inset locking
 206                 bv->lockInset(dynamic_cast<UpdatableInset *>(inset));
 207         }
 208
 209         finishUndo();
 210         return true;
 211 }
 212
 213
 214 // returns false if no undo possible
 215 bool textUndoOrRedo(BufferView * bv,
 216         limited_stack<Undo> & stack, limited_stack<Undo> & otherstack)
 217 {
 218         if (stack.empty()) {
 219                 // nothing to do
 220                 freezeUndo();
 221                 bv->unlockInset(bv->theLockingInset());
 222                 finishUndo();
 223                 unFreezeUndo();
 224                 return false;
 225         }
 226
 227         Undo undo = stack.top();
 228         stack.pop();
 229         finishUndo();
 230
 231         if (!undo_frozen) {
 232                 otherstack.push(undo);
 233                 otherstack.top().pars.clear();
 234                 ParIterator pit = num2pit(bv, undo.text);
 235                 ParagraphList & plist = pit.plist();
 236                 if (undo.first_par + undo.end_par <= int(plist.size())) {
 237                         ParagraphList::iterator first = plist.begin();
 238                         advance(first, undo.first_par);
 239                         ParagraphList::iterator last = plist.begin();
 240                         advance(last, plist.size() - undo.end_par + 1);
 241                         otherstack.top().pars.insert(otherstack.top().pars.begin(), first, last);
 242                 }
 243                 LyXText * text = pit2text(bv, pit);
 244                 otherstack.top().cursor_pos = text->cursor.pos();
 245                 otherstack.top().cursor_par = text->cursor.par();
 246                 lyxerr << " undo other: " << otherstack.top() << std::endl;
 247         }
 248
 249         // Now we can unlock the inset for safety because the inset
 250         // pointer could be changed during the undo-function. Anyway
 251         // if needed we have to lock the right inset/position if this
 252         // is requested.
 253         freezeUndo();
 254         bv->unlockInset(bv->theLockingInset());
 255         bool const ret = performUndoOrRedo(bv, undo);
 256         unFreezeUndo();
 257         return ret;
 258 }
 259
 260 } // namespace anon
 261
 262
 263 void freezeUndo()
 264 {
 265         // this is dangerous and for internal use only
 266         undo_frozen = true;
 267 }
 268
 269
 270 void unFreezeUndo()
 271 {
 272         // this is dangerous and for internal use only
 273         undo_frozen = false;
 274 }
 275
 276
 277 void finishUndo()
 278 {
 279         // makes sure the next operation will be stored
 280         undo_finished = true;
 281 }
 282
 283
 284 bool textUndo(BufferView * bv)
 285 {
 286         return textUndoOrRedo(bv, bv->buffer()->undostack(),
 287                               bv->buffer()->redostack());
 288 }
 289
 290
 291 bool textRedo(BufferView * bv)
 292 {
 293         return textUndoOrRedo(bv, bv->buffer()->redostack(),
 294                               bv->buffer()->undostack());
 295 }
 296
 297
 298 void recordUndo(Undo::undo_kind kind,
 299         LyXText const * text, paroffset_type first, paroffset_type last)
 300 {
 301         if (undo_frozen)
 302                 return;
 303         Buffer * buf = text->bv()->buffer();
 304         recordUndo(kind, const_cast<LyXText *>(text), first, last, buf->undostack());
 305         buf->redostack().clear();
 306 }
 307
 308
 309 void recordUndo(Undo::undo_kind kind, LyXText const * text, paroffset_type par)
 310 {
 311         recordUndo(kind, text, par, par);
 312 }
 313
 314
 315 void recordUndo(BufferView * bv, Undo::undo_kind kind)
 316 {
 317         recordUndo(kind, bv->text, bv->text->cursor.par());
 318 }