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