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