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(BufferView * bv, 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         for ( ; pit != end; ++pit, ++tcount)
  72                 if (pit.text(bv) == text)
  73                         return pit;
  74         lyxerr << "undo: should not happen" << std::endl;
  75         return end;
  76 }
  77
  78
  79 // translates offset from buffer begin to ParIterator
  80 ParIterator num2pit(BufferView * bv, int num)
  81 {
  82         Buffer * buf = bv->buffer();
  83         ParIterator pit = buf->par_iterator_begin();
  84         ParIterator end = buf->par_iterator_end();
  85
  86         for ( ; num && pit != end; ++pit, --num)
  87                 ;
  88
  89         if (pit != end)
  90                 return pit;
  91
  92         // don't crash early...
  93         lyxerr << "undo: num2pit: num: " << num << std::endl;
  94         BOOST_ASSERT(false);
  95         return buf->par_iterator_begin();
  96 }
  97
  98
  99 void recordUndo(Undo::undo_kind kind,
 100         LyXText * text, paroffset_type first_par, paroffset_type last_par,
 101         limited_stack<Undo> & stack)
 102 {
 103         Buffer * buf = text->bv()->buffer();
 104
 105         int const end_par = text->ownerParagraphs().size() - last_par;
 106
 107         // Undo::ATOMIC are always recorded (no overlapping there).
 108         // overlapping only with insert and delete inside one paragraph:
 109         // nobody wants all removed character appear one by one when undoing.
 110         if (!undo_finished && kind != Undo::ATOMIC) {
 111                 // Check whether storing is needed.
 112                 if (!buf->undostack().empty()
 113                     && buf->undostack().top().kind == kind
 114                     && buf->undostack().top().first_par == first_par
 115                     && buf->undostack().top().end_par == end_par) {
 116                         // No additonal undo recording needed -
 117                         // effectively, we combine undo recordings to one.
 118                         return;
 119                 }
 120         }
 121
 122         // make and push the Undo entry
 123         int textnum;
 124         ParIterator pit = text2pit(text->bv(), text, textnum);
 125         stack.push(Undo(kind, textnum, pit.index(),
 126                 first_par, end_par, text->cursor.par(), text->cursor.pos()));
 127         lyxerr << "undo record: " << stack.top() << std::endl;
 128
 129         // record the relevant paragraphs
 130         ParagraphList & undo_pars = stack.top().pars;
 131
 132         ParagraphList & plist = text->ownerParagraphs();
 133         ParagraphList::iterator first = plist.begin();
 134         advance(first, first_par);
 135         ParagraphList::iterator last = plist.begin();
 136         advance(last, last_par);
 137
 138         for (ParagraphList::iterator it = first; it != last; ++it)
 139                 undo_pars.push_back(*it);
 140         undo_pars.push_back(*last);
 141
 142         // and make sure that next time, we should be combining if possible
 143         undo_finished = false;
 144 }
 145
 146
 147 // returns false if no undo possible
 148 bool performUndoOrRedo(BufferView * bv, Undo const & undo)
 149 {
 150         lyxerr << "undo, performing: " << undo << std::endl;
 151         ParIterator pit = num2pit(bv, undo.text);
 152         LyXText * text = pit.text(bv);
 153         ParagraphList & plist = text->ownerParagraphs();
 154
 155         // remove new stuff between first and last
 156         {
 157                 ParagraphList::iterator first = plist.begin();
 158                 advance(first, undo.first_par);
 159                 ParagraphList::iterator last = plist.begin();
 160                 advance(last, plist.size() - undo.end_par);
 161                 plist.erase(first, ++last);
 162         }
 163
 164         // re-insert old stuff instead
 165         if (plist.empty()) {
 166                 plist.assign(undo.pars.begin(), undo.pars.end());
 167         } else {
 168                 ParagraphList::iterator first = plist.begin();
 169                 advance(first, undo.first_par);
 170                 plist.insert(first, undo.pars.begin(), undo.pars.end());
 171         }
 172
 173         // set cursor
 174         lyxerr <<   "undo, text: " << undo.text
 175                << " inset: " << pit.inset()
 176                << " index: " << undo.index
 177                << " par: " << undo.cursor_par
 178                << " pos: " << undo.cursor_pos
 179                << std::endl;
 180
 181         // set cursor again to force the position to be the right one
 182         text->cursor.par(undo.cursor_par);
 183         text->cursor.pos(undo.cursor_pos);
 184
 185         // clear any selection
 186         text->clearSelection();
 187         text->selection.cursor = text->cursor;
 188         text->updateCounters();
 189
 190         // rebreak the entire lyxtext
 191         bv->text->fullRebreak();
 192
 193         pit.lockPath(bv);
 194
 195         finishUndo();
 196         return true;
 197 }
 198
 199
 200 // returns false if no undo possible
 201 bool textUndoOrRedo(BufferView * bv,
 202         limited_stack<Undo> & stack, limited_stack<Undo> & otherstack)
 203 {
 204         if (stack.empty()) {
 205                 // nothing to do
 206                 finishUndo();
 207                 return false;
 208         }
 209
 210         Undo undo = stack.top();
 211         stack.pop();
 212         finishUndo();
 213
 214         if (!undo_frozen) {
 215                 otherstack.push(undo);
 216                 otherstack.top().pars.clear();
 217                 ParIterator pit = num2pit(bv, undo.text);
 218                 ParagraphList & plist = pit.plist();
 219                 if (undo.first_par + undo.end_par <= int(plist.size())) {
 220                         ParagraphList::iterator first = plist.begin();
 221                         advance(first, undo.first_par);
 222                         ParagraphList::iterator last = plist.begin();
 223                         advance(last, plist.size() - undo.end_par + 1);
 224                         otherstack.top().pars.insert(otherstack.top().pars.begin(), first, last);
 225                 }
 226                 LyXText * text = pit.text(bv);
 227                 otherstack.top().cursor_pos = text->cursor.pos();
 228                 otherstack.top().cursor_par = text->cursor.par();
 229                 lyxerr << " undo other: " << otherstack.top() << std::endl;
 230         }
 231
 232         freezeUndo();
 233         bool const ret = performUndoOrRedo(bv, undo);
 234         unFreezeUndo();
 235         return ret;
 236 }
 237
 238 } // namespace anon
 239
 240
 241 void freezeUndo()
 242 {
 243         // this is dangerous and for internal use only
 244         undo_frozen = true;
 245 }
 246
 247
 248 void unFreezeUndo()
 249 {
 250         // this is dangerous and for internal use only
 251         undo_frozen = false;
 252 }
 253
 254
 255 void finishUndo()
 256 {
 257         // makes sure the next operation will be stored
 258         undo_finished = true;
 259 }
 260
 261
 262 bool textUndo(BufferView * bv)
 263 {
 264         return textUndoOrRedo(bv, bv->buffer()->undostack(),
 265                               bv->buffer()->redostack());
 266 }
 267
 268
 269 bool textRedo(BufferView * bv)
 270 {
 271         return textUndoOrRedo(bv, bv->buffer()->redostack(),
 272                               bv->buffer()->undostack());
 273 }
 274
 275
 276 void recordUndo(Undo::undo_kind kind,
 277         LyXText const * text, paroffset_type first, paroffset_type last)
 278 {
 279         if (undo_frozen)
 280                 return;
 281         Buffer * buf = text->bv()->buffer();
 282         recordUndo(kind, const_cast<LyXText *>(text), first, last, buf->undostack());
 283         buf->redostack().clear();
 284 }
 285
 286
 287 void recordUndo(Undo::undo_kind kind, LyXText const * text, paroffset_type par)
 288 {
 289         recordUndo(kind, text, par, par);
 290 }
 291
 292
 293 void recordUndo(BufferView * bv, Undo::undo_kind kind)
 294 {
 295         recordUndo(kind, bv->text, bv->text->cursor.par());
 296 }