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 "cursor.h"
  21 #include "debug.h"
  22 #include "BufferView.h"
  23 #include "lyxtext.h"
  24 #include "paragraph.h"
  25
  26 #include "mathed/math_support.h"
  27
  28 #include <algorithm>
  29
  30 using std::advance;
  31
  32 using lyx::par_type;
  33
  34
  35 namespace {
  36
  37 /// The flag used by finishUndo().
  38 bool undo_finished;
  39
  40
  41 std::ostream & operator<<(std::ostream & os, Undo const & undo)
  42 {
  43         return os << " from: " << undo.from
  44                 << " end: " << undo.end
  45                 << " cursor:\n" << undo.cursor;
  46 }
  47
  48
  49 void recordUndo(Undo::undo_kind kind,
  50         LCursor & cur, par_type first_par, par_type last_par,
  51         limited_stack<Undo> & stack)
  52 {
  53         BOOST_ASSERT(first_par <= cur.lastpar());
  54         BOOST_ASSERT(last_par <= cur.lastpar());
  55
  56         if (first_par > last_par)
  57                 std::swap(first_par, last_par);
  58
  59         // create the position information of the Undo entry
  60         Undo undo;
  61         undo.kind = kind;
  62         undo.cursor = StableDocumentIterator(cur);
  63         undo.from = first_par;
  64         undo.end = cur.lastpar() - last_par;
  65
  66         // Undo::ATOMIC are always recorded (no overlapping there).
  67         // As nobody wants all removed character appear one by one when undoing,
  68         // we want combine 'similar' non-ATOMIC undo recordings to one.
  69         if (!undo_finished
  70             && kind != Undo::ATOMIC
  71             && !stack.empty()
  72             && stack.top().cursor.size() == undo.cursor.size()
  73                   && stack.top().kind == undo.kind
  74                   && stack.top().from == undo.from
  75                   && stack.top().end == undo.end)
  76                 return;
  77
  78         // fill in the real data to be saved
  79         if (cur.inMathed()) {
  80                 // simply use the whole cell
  81                 undo.array = asString(cur.cell());
  82         } else {
  83                 // some more effort needed here as 'the whole cell' of the
  84                 // main LyXText _is_ the whole document.
  85                 // record the relevant paragraphs
  86                 LyXText * text = cur.text();
  87                 BOOST_ASSERT(text);
  88                 ParagraphList & plist = text->paragraphs();
  89                 ParagraphList::iterator first = plist.begin();
  90                 advance(first, first_par);
  91                 ParagraphList::iterator last = plist.begin();
  92                 advance(last, last_par + 1);
  93                 undo.pars = ParagraphList(first, last);
  94         }
  95
  96         // push the undo entry to undo stack
  97         //lyxerr << "undo record: " << stack.top() << std::endl;
  98         stack.push(undo);
  99
 100         // next time we'll try again to combine entries if possible
 101         undo_finished = false;
 102 }
 103
 104
 105 void performUndoOrRedo(BufferView & bv, Undo const & undo)
 106 {
 107         LCursor & cur = bv.cursor();
 108         lyxerr << "undo, performing: " << undo << std::endl;
 109         cur.setCursor(undo.cursor.asDocumentIterator(&bv.buffer()->inset()), false);
 110
 111         if (cur.inMathed()) {
 112                 // We stored the full cell here as there is not much to be
 113                 // gained by storing just 'a few' paragraphs (most if not
 114                 // all math inset cells have just one paragraph!)
 115                 asArray(undo.array, cur.cell());
 116         } else {
 117                 // Some finer machinery is needed here.
 118                 LyXText * text = cur.text();
 119                 BOOST_ASSERT(text);
 120                 ParagraphList & plist = text->paragraphs();
 121
 122                 // remove new stuff between first and last
 123                 ParagraphList::iterator first = plist.begin();
 124                 advance(first, undo.from);
 125                 ParagraphList::iterator last = plist.begin();
 126                 advance(last, plist.size() - undo.end);
 127                 plist.erase(first, last);
 128
 129                 // re-insert old stuff instead
 130                 first = plist.begin();
 131                 advance(first, undo.from);
 132                 plist.insert(first, undo.pars.begin(), undo.pars.end());
 133         }
 134
 135         cur.resetAnchor();
 136         finishUndo();
 137 }
 138
 139
 140 // returns false if no undo possible
 141 bool textUndoOrRedo(BufferView & bv,
 142         limited_stack<Undo> & stack, limited_stack<Undo> & otherstack)
 143 {
 144         if (stack.empty()) {
 145                 // nothing to do
 146                 finishUndo();
 147                 return false;
 148         }
 149
 150         Undo undo = stack.top();
 151         stack.pop();
 152         finishUndo();
 153
 154         // this implements redo
 155         otherstack.push(undo);
 156         DocumentIterator dit =
 157                 undo.cursor.asDocumentIterator(&bv.buffer()->inset());
 158         if (dit.inMathed()) {
 159                 // not much to be done
 160         } else {
 161                 otherstack.top().pars.clear();
 162                 LyXText * text = dit.text();
 163                 BOOST_ASSERT(text);
 164                 ParagraphList & plist = text->paragraphs();
 165                 if (undo.from + undo.end <= int(plist.size())) {
 166                         ParagraphList::iterator first = plist.begin();
 167                         advance(first, undo.from);
 168                         ParagraphList::iterator last = plist.begin();
 169                         advance(last, plist.size() - undo.end);
 170                         otherstack.top().pars.insert(otherstack.top().pars.begin(), first, last);
 171                 }
 172         }
 173         otherstack.top().cursor = bv.cursor();
 174         //lyxerr << " undo other: " << otherstack.top() << std::endl;
 175
 176         performUndoOrRedo(bv, undo);
 177         return true;
 178 }
 179
 180 } // namespace anon
 181
 182
 183 void finishUndo()
 184 {
 185         // makes sure the next operation will be stored
 186         undo_finished = true;
 187 }
 188
 189
 190 bool textUndo(BufferView & bv)
 191 {
 192         return textUndoOrRedo(bv, bv.buffer()->undostack(),
 193                               bv.buffer()->redostack());
 194 }
 195
 196
 197 bool textRedo(BufferView & bv)
 198 {
 199         return textUndoOrRedo(bv, bv.buffer()->redostack(),
 200                               bv.buffer()->undostack());
 201 }
 202
 203
 204 void recordUndo(Undo::undo_kind kind,
 205         LCursor & cur, par_type first, par_type last)
 206 {
 207         Buffer * buf = cur.bv().buffer();
 208         recordUndo(kind, cur, first, last, buf->undostack());
 209         buf->redostack().clear();
 210         //lyxerr << "undostack:\n";
 211         //for (size_t i = 0, n = buf->undostack().size(); i != n && i < 6; ++i)
 212         //      lyxerr << "  " << i << ": " << buf->undostack()[i] << std::endl;
 213 }
 214
 215
 216 void recordUndo(LCursor & cur, Undo::undo_kind kind)
 217 {
 218         recordUndo(kind, cur, cur.par(), cur.par());
 219 }
 220
 221
 222 void recordUndoSelection(LCursor & cur, Undo::undo_kind kind)
 223 {
 224         recordUndo(kind, cur, cur.selBegin().par(), cur.selEnd().par());
 225 }
 226
 227
 228 void recordUndo(LCursor & cur, Undo::undo_kind kind, par_type from)
 229 {
 230         recordUndo(kind, cur, cur.par(), from);
 231 }
 232
 233
 234 void recordUndo(LCursor & cur, Undo::undo_kind kind,
 235         par_type from, par_type to)
 236 {
 237         recordUndo(kind, cur, from, to);
 238 }
 239
 240
 241 void recordUndoFullDocument(LCursor &)
 242 {
 243         //recordUndo(Undo::ATOMIC,
 244         //      cur, 0, cur.bv().text()->paragraphs().size() - 1);
 245 }