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