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