src/Changes.cpp

   1 /**
   2  * \file Changes.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author John Levon
   7  * \author Michael Gerz
   8  *
   9  * Full author contact details are available in file CREDITS.
  10  *
  11  * Record changes in a paragraph.
  12  */
  13
  14 #include <config.h>
  15
  16 #include "Changes.h"
  17 #include "debug.h"
  18 #include "Author.h"
  19 #include "BufferParams.h"
  20 #include "LaTeXFeatures.h"
  21
  22 #include <boost/assert.hpp>
  23
  24 using std::abs;
  25 using std::endl;
  26 using std::string;
  27 using std::max;
  28
  29 namespace lyx {
  30
  31 /*
  32  * Class Change has a changetime field that specifies the exact time at which
  33  * a specific change was made. The change time is used as a guidance for the
  34  * user while editing his document. Presently, it is not considered for LaTeX
  35  * export.
  36  * When merging two adjacent changes, the changetime is not considered,
  37  * only the equality of the change type and author is checked (in method
  38  * isSimilarTo(...)). If two changes are in fact merged (in method merge()),
  39  * the later change time is preserved.
  40  */
  41
  42 bool Change::isSimilarTo(Change const & change)
  43 {
  44         if (type != change.type) {
  45                 return false;
  46         }
  47
  48         if (type == Change::UNCHANGED) {
  49                 return true;
  50         }
  51
  52         return author == change.author;
  53 }
  54
  55
  56 bool operator==(Change const & l, Change const & r)
  57 {
  58         if (l.type != r.type) {
  59                 return false;
  60         }
  61
  62         // two changes of type UNCHANGED are always equal
  63         if (l.type == Change::UNCHANGED) {
  64                 return true;
  65         }
  66
  67         return l.author == r.author &&
  68                l.changetime == r.changetime;
  69 }
  70
  71
  72 bool operator!=(Change const & l, Change const & r)
  73 {
  74         return !(l == r);
  75 }
  76
  77
  78 bool operator==(Changes::Range const & r1, Changes::Range const & r2)
  79 {
  80         return r1.start == r2.start && r1.end == r2.end;
  81 }
  82
  83
  84 bool operator!=(Changes::Range const & r1, Changes::Range const & r2)
  85 {
  86         return !(r1 == r2);
  87 }
  88
  89
  90 bool Changes::Range::intersects(Range const & r) const
  91 {
  92         return r.start < end && r.end > start; // end itself is not in the range!
  93 }
  94
  95
  96 void Changes::set(Change const & change, pos_type const pos)
  97 {
  98         set(change, pos, pos + 1);
  99 }
 100
 101
 102 void Changes::set(Change const & change, pos_type const start, pos_type const end)
 103 {
 104         if (change.type != Change::UNCHANGED) {
 105                 LYXERR(Debug::CHANGES) << "setting change (type: " << change.type
 106                         << ", author: " << change.author << ", time: " << change.changetime
 107                         << ") in range (" << start << ", " << end << ")" << endl;
 108         }
 109
 110         Range const newRange(start, end);
 111
 112         ChangeTable::iterator it = table_.begin();
 113
 114         for (; it != table_.end(); ) {
 115                 // current change starts like or follows new change
 116                 if (it->range.start >= start) {
 117                         break;
 118                 }
 119
 120                 // new change intersects with existing change
 121                 if (it->range.end > start) {
 122                         pos_type oldEnd = it->range.end;
 123                         it->range.end = start;
 124
 125                         LYXERR(Debug::CHANGES) << "  cutting tail of type " << it->change.type
 126                                 << " resulting in range (" << it->range.start << ", "
 127                                 << it->range.end << ")" << endl;
 128
 129                         ++it;
 130                         if (oldEnd >= end) {
 131                                 LYXERR(Debug::CHANGES) << "  inserting tail in range ("
 132                                         << end << ", " << oldEnd << ")" << endl;
 133                                 it = table_.insert(it, ChangeRange((it-1)->change, Range(end, oldEnd)));
 134                         }
 135                         continue;
 136                 }
 137
 138                 ++it;
 139         }
 140
 141         if (change.type != Change::UNCHANGED) {
 142                 LYXERR(Debug::CHANGES) << "  inserting change" << endl;
 143                 it = table_.insert(it, ChangeRange(change, Range(start, end)));
 144                 ++it;
 145         }
 146
 147         for (; it != table_.end(); ) {
 148                 // new change 'contains' existing change
 149                 if (newRange.contains(it->range)) {
 150                         LYXERR(Debug::CHANGES) << "  removing subrange ("
 151                                 << it->range.start << ", " << it->range.end << ")" << endl;
 152                         it = table_.erase(it);
 153                         continue;
 154                 }
 155
 156                 // new change precedes existing change
 157                 if (it->range.start >= end) {
 158                         break;
 159                 }
 160
 161                 // new change intersects with existing change
 162                 it->range.start = end;
 163                 LYXERR(Debug::CHANGES) << "  cutting head of type "
 164                         << it->change.type << " resulting in range ("
 165                         << end << ", " << it->range.end << ")" << endl;
 166                 break; // no need for another iteration
 167         }
 168
 169         merge();
 170 }
 171
 172
 173 void Changes::erase(pos_type const pos)
 174 {
 175         LYXERR(Debug::CHANGES) << "Erasing change at position " << pos << endl;
 176
 177         ChangeTable::iterator it = table_.begin();
 178         ChangeTable::iterator end = table_.end();
 179
 180         for (; it != end; ++it) {
 181                 // range (pos,pos+x) becomes (pos,pos+x-1)
 182                 if (it->range.start > pos) {
 183                         --(it->range.start);
 184                 }
 185                 // range (pos-x,pos) stays (pos-x,pos)
 186                 if (it->range.end > pos) {
 187                         --(it->range.end);
 188                 }
 189         }
 190
 191         merge();
 192 }
 193
 194
 195 void Changes::insert(Change const & change, lyx::pos_type pos)
 196 {
 197         if (change.type != Change::UNCHANGED) {
 198                 LYXERR(Debug::CHANGES) << "Inserting change of type " << change.type
 199                         << " at position " << pos << endl;
 200         }
 201
 202         ChangeTable::iterator it = table_.begin();
 203         ChangeTable::iterator end = table_.end();
 204
 205         for (; it != end; ++it) {
 206                 // range (pos,pos+x) becomes (pos+1,pos+x+1)
 207                 if (it->range.start >= pos) {
 208                         ++(it->range.start);
 209                 }
 210
 211                 // range (pos-x,pos) stays as it is
 212                 if (it->range.end > pos) {
 213                         ++(it->range.end);
 214                 }
 215         }
 216
 217         set(change, pos, pos + 1); // set will call merge
 218 }
 219
 220
 221 Change const & Changes::lookup(pos_type const pos) const
 222 {
 223         static Change const noChange = Change(Change::UNCHANGED);
 224
 225         ChangeTable::const_iterator it = table_.begin();
 226         ChangeTable::const_iterator const end = table_.end();
 227
 228         for (; it != end; ++it) {
 229                 if (it->range.contains(pos))
 230                         return it->change;
 231         }
 232
 233         return noChange;
 234 }
 235
 236
 237 bool Changes::isChanged(pos_type const start, pos_type const end) const
 238 {
 239         ChangeTable::const_iterator it = table_.begin();
 240         ChangeTable::const_iterator const itend = table_.end();
 241
 242         for (; it != itend; ++it) {
 243                 if (it->range.intersects(Range(start, end))) {
 244                         LYXERR(Debug::CHANGES) << "found intersection of range ("
 245                                 << start << ", " << end << ") with ("
 246                                 << it->range.start << ", " << it->range.end
 247                                 << ") of type " << it->change.type << endl;
 248                         return true;
 249                 }
 250         }
 251         return false;
 252 }
 253
 254
 255 void Changes::merge()
 256 {
 257         ChangeTable::iterator it = table_.begin();
 258
 259         while (it != table_.end()) {
 260                 LYXERR(Debug::CHANGES) << "found change of type " << it->change.type
 261                         << " and range (" << it->range.start << ", " << it->range.end
 262                         << ")" << endl;
 263
 264                 if (it->range.start == it->range.end) {
 265                         LYXERR(Debug::CHANGES) << "removing empty range for pos "
 266                                 << it->range.start << endl;
 267
 268                         table_.erase(it);
 269                         // start again
 270                         it = table_.begin();
 271                         continue;
 272                 }
 273
 274                 if (it + 1 == table_.end())
 275                         break;
 276
 277                 if (it->change.isSimilarTo((it + 1)->change) && it->range.end == (it + 1)->range.start) {
 278                         LYXERR(Debug::CHANGES) << "merging ranges (" << it->range.start << ", "
 279                                 << it->range.end << ") and (" << (it + 1)->range.start << ", "
 280                                 << (it + 1)->range.end << ")" << endl;
 281
 282                         (it + 1)->range.start = it->range.start;
 283                         (it + 1)->change.changetime = max(it->change.changetime,
 284                                                           (it + 1)->change.changetime);
 285                         table_.erase(it);
 286                         // start again
 287                         it = table_.begin();
 288                         continue;
 289                 }
 290
 291                 ++it;
 292         }
 293 }
 294
 295
 296 int Changes::latexMarkChange(odocstream & os, BufferParams const & bparams,
 297                              Change const & oldChange, Change const & change)
 298 {
 299         if (!bparams.outputChanges || oldChange == change)
 300                 return 0;
 301
 302         int column = 0;
 303
 304         if (oldChange.type != Change::UNCHANGED) {
 305                 os << '}'; // close \lyxadded or \lyxdeleted
 306                 column++;
 307         }
 308
 309         docstring chgTime;
 310         chgTime += ctime(&change.changetime);
 311         chgTime.erase(chgTime.end() - 1); // remove trailing '\n'
 312
 313         if (change.type == Change::DELETED) {
 314                 docstring str = "\\lyxdeleted{" +
 315                         bparams.authors().get(change.author).name() + "}{" +
 316                         chgTime + "}{";
 317                 os << str;
 318                 column += str.size();
 319         } else if (change.type == Change::INSERTED) {
 320                 docstring str = "\\lyxadded{" +
 321                         bparams.authors().get(change.author).name() + "}{" +
 322                         chgTime + "}{";
 323                 os << str;
 324                 column += str.size();
 325         }
 326
 327         return column;
 328 }
 329
 330
 331 void Changes::lyxMarkChange(std::ostream & os, int & column,
 332                             Change const & old, Change const & change)
 333 {
 334         if (old == change)
 335                 return;
 336
 337         column = 0;
 338
 339         switch (change.type) {
 340                 case Change::UNCHANGED:
 341                         os << "\n\\change_unchanged\n";
 342                         break;
 343
 344                 case Change::DELETED: {
 345                         os << "\n\\change_deleted " << change.author
 346                                 << " " << change.changetime << "\n";
 347                         break;
 348                 }
 349
 350                 case Change::INSERTED: {
 351                         os << "\n\\change_inserted " << change.author
 352                                 << " " << change.changetime << "\n";
 353                         break;
 354                 }
 355         }
 356 }
 357
 358
 359 void Changes::checkAuthors(AuthorList const & authorList)
 360 {
 361         ChangeTable::const_iterator it = table_.begin();
 362         ChangeTable::const_iterator endit = table_.end();
 363         for ( ; it != endit ; ++it)
 364                 if (it->change.type != Change::UNCHANGED)
 365                         authorList.get(it->change.author).used(true);
 366 }
 367
 368 } // namespace lyx