src/undo_funcs.C

   1 /**
   2  * \file undo_funcs.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_funcs.h"
  18
  19 #include "buffer.h"
  20 #include "debug.h"
  21 #include "BufferView.h"
  22 #include "funcrequest.h"
  23 #include "iterators.h"
  24 #include "lyxtext.h"
  25 #include "paragraph.h"
  26
  27 #include "insets/updatableinset.h"
  28
  29 #include <iostream>
  30
  31 using std::endl;
  32 using lyx::paroffset_type;
  33
  34
  35 /// The flag used by finishUndo().
  36 bool undo_finished;
  37
  38 /// Whether actions are not added to the undo stacks.
  39 bool undo_frozen;
  40
  41 namespace {
  42
  43
  44 void recordUndo(BufferView * bv, Undo::undo_kind kind,
  45         ParagraphList & plist, paroffset_type firstpar, paroffset_type lastpar,
  46         limited_stack<Undo> & stack)
  47 {
  48         Buffer * buf = bv->buffer();
  49
  50         ParagraphList::iterator first = plist.begin();
  51         advance(first, firstpar);
  52         ParagraphList::iterator last = plist.begin();
  53         advance(last, lastpar);
  54
  55         // First, record inset id, if cursor is in one
  56         UpdatableInset * inset = first->inInset();
  57         LyXText * text = inset ? inset->getLyXText(bv) : bv->text;
  58         int const inset_id = inset ? inset->id() : -1;
  59
  60         // Try to find the appropriate list by counting the,
  61         ParIterator null = buf->par_iterator_end();
  62
  63         int pcount = 0;
  64         for (ParIterator it = buf->par_iterator_begin(); it != null; ++it, ++pcount)
  65                 if (&it.plist() == &plist)
  66                         break;
  67
  68         // And calculate a stable reference to them
  69         int const first_offset = firstpar;
  70         int const last_offset = plist.size() - lastpar;
  71
  72         // Undo::ATOMIC are always recorded (no overlapping there).
  73         // Overlapping only with insert and delete inside one paragraph:
  74         // Nobody wants all removed character appear one by one when undoing.
  75         if (! undo_finished && kind != Undo::ATOMIC) {
  76                 // Check whether storing is needed.
  77                 if (! buf->undostack().empty()
  78                     && buf->undostack().top().kind == kind
  79                     && buf->undostack().top().first_par_offset == first_offset
  80                     && buf->undostack().top().last_par_offset == last_offset) {
  81                         // No additonal undo recording needed -
  82                         // effectively, we combine undo recordings to one.
  83                         return;
  84                 }
  85         }
  86
  87         // Record the cursor position in a stable way.
  88         int const cursor_offset = text->cursor.par();
  89
  90         // Make and push the Undo entry
  91         stack.push(Undo(kind, inset_id,
  92                 pcount,
  93                 first_offset, last_offset,
  94                 cursor_offset, text->cursor.pos(),
  95                 ParagraphList()));
  96
  97         // Record the relevant paragraphs
  98         ParagraphList & undo_pars = stack.top().pars;
  99
 100         for (ParagraphList::iterator it = first; it != last; ++it) {
 101                 undo_pars.push_back(*it);
 102                 undo_pars.back().id(it->id());
 103         }
 104         undo_pars.push_back(*last);
 105         undo_pars.back().id(last->id());
 106
 107         // And make sure that next time, we should be combining if possible
 108         undo_finished = false;
 109 }
 110
 111
 112 // Returns false if no undo possible.
 113 bool performUndoOrRedo(BufferView * bv, Undo const & undo)
 114 {
 115         Buffer * buf = bv->buffer();
 116
 117         ParIterator null = buf->par_iterator_end();
 118         ParIterator plit = buf->par_iterator_begin();
 119         int n = undo.plist;
 120         for ( ; n && plit != null; ++plit, --n)
 121                 ;
 122         BOOST_ASSERT(plit != null);
 123         ParagraphList & plist = plit.plist();
 124
 125         // Remove new stuff between first and last
 126         {
 127                 ParagraphList::iterator first = plist.begin();
 128                 advance(first, undo.first_par_offset);
 129                 ParagraphList::iterator last = plist.begin();
 130                 advance(last, plist.size() - undo.last_par_offset);
 131                 plist.erase(first, ++last);
 132         }
 133
 134         // Re-insert old stuff instead
 135         {
 136                 if (plist.empty()) {
 137                         plist.assign(undo.pars.begin(), undo.pars.end());
 138                 } else {
 139                         ParagraphList::iterator first = plist.begin();
 140                         advance(first, undo.first_par_offset);
 141                         plist.insert(first, undo.pars.begin(), undo.pars.end());
 142                 }
 143         }
 144
 145         // Rebreak the entire document
 146         bv->text->fullRebreak();
 147
 148         // set cursor
 149         {
 150                 // Get a hold of the inset for the cursor, if relevant
 151                 UpdatableInset * inset =
 152                         static_cast<UpdatableInset *>(
 153                                 buf->getInsetFromID(undo.inset_id));
 154
 155                 LyXText * text = inset ? inset->getLyXText(bv) : bv->text;
 156                 text->setCursorIntern(undo.cursor_par_offset, undo.cursor_pos);
 157
 158                 //lyxerr << "undo, inset: " << inset << endl;
 159
 160                 if (inset) {
 161                         //lyxerr << "undo, inset owner: " << inset->owner() << endl;
 162
 163                         // Magic needed to update inset internal state
 164                         FuncRequest cmd(bv, LFUN_INSET_EDIT, "left");
 165                         if (inset->owner())
 166                                 inset->owner()->localDispatch(cmd);
 167                         else
 168                                 inset->localDispatch(cmd);
 169                 }
 170
 171                 // set cursor again to force the position to be the right one
 172                 text->setCursorIntern(undo.cursor_par_offset, undo.cursor_pos);
 173
 174                 // Clear any selection and set the selection
 175                 // cursor for any new selection.
 176                 text->clearSelection();
 177                 text->selection.cursor = text->cursor;
 178                 text->updateCounters();
 179         }
 180
 181         finishUndo();
 182         return true;
 183 }
 184
 185
 186 // Returns false if no undo possible.
 187 bool textUndoOrRedo(BufferView * bv,
 188         limited_stack<Undo> & stack,
 189         limited_stack<Undo> & otherstack)
 190 {
 191         if (stack.empty()) {
 192                 /*
 193                  * Finish the undo operation in the case there was no entry
 194                  * on the stack to perform.
 195                  */
 196                 freezeUndo();
 197                 bv->unlockInset(bv->theLockingInset());
 198                 finishUndo();
 199                 unFreezeUndo();
 200                 return false;
 201         }
 202
 203         Undo undo = stack.top();
 204         stack.pop();
 205         finishUndo();
 206
 207         if (!undo_frozen) {
 208                 otherstack.push(undo);
 209                 otherstack.top().pars.clear();
 210                 Buffer * buf = bv->buffer();
 211                 ParagraphList & plist = buf->paragraphs();
 212                 if (undo.first_par_offset + undo.last_par_offset <= int(plist.size())) {
 213                         ParagraphList::iterator first = plist.begin();
 214                         advance(first, undo.first_par_offset);
 215                         ParagraphList::iterator last = plist.begin();
 216                         advance(last, plist.size() - undo.last_par_offset + 1);
 217                         otherstack.top().pars.insert(otherstack.top().pars.begin(), first, last);
 218                 }
 219         }
 220
 221         // Now we can unlock the inset for safety because the inset
 222         // pointer could be changed during the undo-function. Anyway
 223         // if needed we have to lock the right inset/position if this
 224         // is requested.
 225         freezeUndo();
 226         bv->unlockInset(bv->theLockingInset());
 227         bool const ret = performUndoOrRedo(bv, undo);
 228         unFreezeUndo();
 229         return ret;
 230 }
 231
 232 } // namespace anon
 233
 234
 235 void freezeUndo()
 236 {
 237         // This is dangerous and for internal use only.
 238         undo_frozen = true;
 239 }
 240
 241
 242 void unFreezeUndo()
 243 {
 244         // This is dangerous and for internal use only.
 245         undo_frozen = false;
 246 }
 247
 248
 249 void finishUndo()
 250 {
 251         // Makes sure the next operation will be stored.
 252         undo_finished = true;
 253 }
 254
 255
 256 bool textUndo(BufferView * bv)
 257 {
 258         return textUndoOrRedo(bv, bv->buffer()->undostack(),
 259                               bv->buffer()->redostack());
 260 }
 261
 262
 263 bool textRedo(BufferView * bv)
 264 {
 265         return textUndoOrRedo(bv, bv->buffer()->redostack(),
 266                               bv->buffer()->undostack());
 267 }
 268
 269
 270 void recordUndo(BufferView * bv, Undo::undo_kind kind,
 271         ParagraphList & plist, paroffset_type first, paroffset_type last)
 272 {
 273         if (!undo_frozen) {
 274                 recordUndo(bv, kind, plist, first, last, bv->buffer()->undostack());
 275                 bv->buffer()->redostack().clear();
 276         }
 277 }
 278
 279
 280 void recordUndo(BufferView * bv, Undo::undo_kind kind,
 281         ParagraphList & plist, paroffset_type par)
 282 {
 283         recordUndo(bv, kind, plist, par, par);
 284 }
 285
 286
 287 void recordUndo(BufferView * bv, Undo::undo_kind kind)
 288 {
 289         recordUndo(bv, kind, bv->text->ownerParagraphs(), bv->text->cursor.par());
 290 }