lib/diff.php

   1 <?php
   2 // PukiWiki - Yet another WikiWikiWeb clone.
   3 // $Id: diff.php,v 1.10 2011/01/25 15:01:01 henoheno Exp $
   4 // Copyright (C)
   5 //   2003-2005, 2007 PukiWiki Developers Team
   6 //   2001-2002 Originally written by yu-ji
   7 // License: GPL v2 or (at your option) any later version
   8 //
   9
  10 // Show more information when it conflicts
  11 define('PKWK_DIFF_SHOW_CONFLICT_DETAIL', 1);
  12
  13 // Create diff-style data between arrays
  14 function do_diff($strlines1, $strlines2)
  15 {
  16         $obj = new line_diff();
  17         $str = $obj->str_compare($strlines1, $strlines2);
  18         return $str;
  19 }
  20
  21 // Visualize diff-style-text to text-with-CSS
  22 //   '+Added'   => '<span added>Added</span>'
  23 //   '-Removed' => '<span removed>Removed</span>'
  24 //   ' Nothing' => 'Nothing'
  25 function diff_style_to_css($str = '')
  26 {
  27         // Cut diff markers ('+' or '-' or ' ')
  28         $str = preg_replace('/^\-(.*)$/m', '<span class="diff_removed">$1</span>', $str);
  29         $str = preg_replace('/^\+(.*)$/m', '<span class="diff_added"  >$1</span>', $str);
  30         return preg_replace('/^ (.*)$/m',  '$1', $str);
  31 }
  32
  33 // Merge helper (when it conflicts)
  34 function do_update_diff($pagestr, $poststr, $original)
  35 {
  36         $obj = new line_diff();
  37
  38         $obj->set_str('left', $original, $pagestr);
  39         $obj->compare();
  40         $diff1 = $obj->toArray();
  41
  42         $obj->set_str('right', $original, $poststr);
  43         $obj->compare();
  44         $diff2 = $obj->toArray();
  45
  46         $arr = $obj->arr_compare('all', $diff1, $diff2);
  47
  48         if (PKWK_DIFF_SHOW_CONFLICT_DETAIL) {
  49                 global $do_update_diff_table;
  50                 $table = array();
  51                 $table[] = <<<EOD
  52 <p>l : between backup data and stored page data.<br />
  53  r : between backup data and your post data.</p>
  54 <table class="style_table">
  55  <tr>
  56   <th>l</th>
  57   <th>r</th>
  58   <th>text</th>
  59  </tr>
  60 EOD;
  61                 $tags = array('th', 'th', 'td');
  62                 foreach ($arr as $_obj) {
  63                         $table[] = ' <tr>';
  64                         $params = array($_obj->get('left'), $_obj->get('right'), $_obj->text());
  65                         foreach ($params as $key => $text) {
  66                                 $text = htmlsc(rtrim($text));
  67                                 if (empty($text)) $text = '&nbsp;';
  68                                 $table[] =
  69                                         '  <' . $tags[$key] . ' class="style_' . $tags[$key] . '">' .
  70                                         $text .
  71                                         '</' . $tags[$key] . '>';
  72                         }
  73                         $table[] = ' </tr>';
  74                 }
  75                 $table[] =  '</table>';
  76
  77                 $do_update_diff_table = implode("\n", $table) . "\n";
  78                 unset($table);
  79         }
  80
  81         $body = array();
  82         foreach ($arr as $_obj) {
  83                 if ($_obj->get('left') != '-' && $_obj->get('right') != '-') {
  84                         $body[] = $_obj->text();
  85                 }
  86         }
  87
  88         return array(rtrim(implode('', $body)) . "\n", 1);
  89 }
  90
  91
  92 // References of this class:
  93 // S. Wu, <A HREF="http://www.cs.arizona.edu/people/gene/vita.html">
  94 // E. Myers,</A> U. Manber, and W. Miller,
  95 // <A HREF="http://www.cs.arizona.edu/people/gene/PAPERS/np_diff.ps">
  96 // "An O(NP) Sequence Comparison Algorithm,"</A>
  97 // Information Processing Letters 35, 6 (1990), 317-323.
  98 class line_diff
  99 {
 100         var $arr1, $arr2, $m, $n, $pos, $key, $plus, $minus, $equal, $reverse;
 101
 102         function line_diff($plus = '+', $minus = '-', $equal = ' ')
 103         {
 104                 $this->plus  = $plus;
 105                 $this->minus = $minus;
 106                 $this->equal = $equal;
 107         }
 108
 109         function arr_compare($key, $arr1, $arr2)
 110         {
 111                 $this->key  = $key;
 112                 $this->arr1 = $arr1;
 113                 $this->arr2 = $arr2;
 114                 $this->compare();
 115                 $arr = $this->toArray();
 116                 return $arr;
 117         }
 118
 119         function set_str($key, $str1, $str2)
 120         {
 121                 $this->key  = $key;
 122                 $this->arr1 = array();
 123                 $this->arr2 = array();
 124                 $str1 = str_replace("\r", '', $str1);
 125                 $str2 = str_replace("\r", '', $str2);
 126                 foreach (explode("\n", $str1) as $line) {
 127                         $this->arr1[] = new DiffLine($line);
 128                 }
 129                 foreach (explode("\n", $str2) as $line) {
 130                         $this->arr2[] = new DiffLine($line);
 131                 }
 132         }
 133
 134         function str_compare($str1, $str2)
 135         {
 136                 $this->set_str('diff', $str1, $str2);
 137                 $this->compare();
 138
 139                 $str = '';
 140                 foreach ($this->toArray() as $obj) {
 141                         $str .= $obj->get('diff') . $obj->text();
 142                 }
 143                 return $str;
 144         }
 145
 146         function compare()
 147         {
 148                 $this->m = count($this->arr1);
 149                 $this->n = count($this->arr2);
 150
 151                 if ($this->m == 0 || $this->n == 0) { // No need to compare
 152                         $this->result = array(array('x'=>0, 'y'=>0));
 153                         return;
 154                 }
 155
 156                 // Sentinel
 157                 array_unshift($this->arr1, new DiffLine(''));
 158                 $this->m++;
 159                 array_unshift($this->arr2, new DiffLine(''));
 160                 $this->n++;
 161
 162                 $this->reverse = ($this->n < $this->m);
 163                 if ($this->reverse) {
 164                         // Swap
 165                         $tmp = $this->m; $this->m = $this->n; $this->n = $tmp;
 166                         $tmp = $this->arr1; $this->arr1 = $this->arr2; $this->arr2 = $tmp;
 167                         unset($tmp);
 168                 }
 169
 170                 $delta = $this->n - $this->m; // Must be >=0;
 171
 172                 $fp = array();
 173                 $this->path = array();
 174
 175                 for ($p = -($this->m + 1); $p <= ($this->n + 1); $p++) {
 176                         $fp[$p] = -1;
 177                         $this->path[$p] = array();
 178                 }
 179
 180                 for ($p = 0;; $p++) {
 181                         for ($k = -$p; $k <= $delta - 1; $k++) {
 182                                 $fp[$k] = $this->snake($k, $fp[$k - 1], $fp[$k + 1]);
 183                         }
 184                         for ($k = $delta + $p; $k >= $delta + 1; $k--) {
 185                                 $fp[$k] = $this->snake($k, $fp[$k - 1], $fp[$k + 1]);
 186                         }
 187                         $fp[$delta] = $this->snake($delta, $fp[$delta - 1], $fp[$delta + 1]);
 188                         if ($fp[$delta] >= $this->n) {
 189                                 $this->pos = $this->path[$delta]; // 経路を決定
 190                                 return;
 191                         }
 192                 }
 193         }
 194
 195         function snake($k, $y1, $y2)
 196         {
 197                 if ($y1 >= $y2) {
 198                         $_k = $k - 1;
 199                         $y = $y1 + 1;
 200                 } else {
 201                         $_k = $k + 1;
 202                         $y = $y2;
 203                 }
 204                 $this->path[$k] = $this->path[$_k];// ここまでの経路をコピー
 205                 $x = $y - $k;
 206                 while ((($x + 1) < $this->m) && (($y + 1) < $this->n)
 207                         and $this->arr1[$x + 1]->compare($this->arr2[$y + 1]))
 208                 {
 209                         ++$x; ++$y;
 210                         $this->path[$k][] = array('x'=>$x, 'y'=>$y); // 経路を追加
 211                 }
 212                 return $y;
 213         }
 214
 215         function toArray()
 216         {
 217                 $arr = array();
 218                 if ($this->reverse) { // 姑息な…
 219                         $_x = 'y'; $_y = 'x'; $_m = $this->n; $arr1 =& $this->arr2; $arr2 =& $this->arr1;
 220                 } else {
 221                         $_x = 'x'; $_y = 'y'; $_m = $this->m; $arr1 =& $this->arr1; $arr2 =& $this->arr2;
 222                 }
 223
 224                 $x = $y = 1;
 225                 $this->add_count = $this->delete_count = 0;
 226                 $this->pos[] = array('x'=>$this->m, 'y'=>$this->n); // Sentinel
 227                 foreach ($this->pos as $pos) {
 228                         $this->delete_count += ($pos[$_x] - $x);
 229                         $this->add_count    += ($pos[$_y] - $y);
 230
 231                         while ($pos[$_x] > $x) {
 232                                 $arr1[$x]->set($this->key, $this->minus);
 233                                 $arr[] = $arr1[$x++];
 234                         }
 235
 236                         while ($pos[$_y] > $y) {
 237                                 $arr2[$y]->set($this->key, $this->plus);
 238                                 $arr[] =  $arr2[$y++];
 239                         }
 240
 241                         if ($x < $_m) {
 242                                 $arr1[$x]->merge($arr2[$y]);
 243                                 $arr1[$x]->set($this->key, $this->equal);
 244                                 $arr[] = $arr1[$x];
 245                         }
 246                         ++$x; ++$y;
 247                 }
 248                 return $arr;
 249         }
 250 }
 251
 252 class DiffLine
 253 {
 254         var $text;
 255         var $status;
 256
 257         function DiffLine($text)
 258         {
 259                 $this->text   = $text . "\n";
 260                 $this->status = array();
 261         }
 262
 263         function compare($obj)
 264         {
 265                 return $this->text == $obj->text;
 266         }
 267
 268         function set($key, $status)
 269         {
 270                 $this->status[$key] = $status;
 271         }
 272
 273         function get($key)
 274         {
 275                 return isset($this->status[$key]) ? $this->status[$key] : '';
 276         }
 277
 278         function merge($obj)
 279         {
 280                 $this->status += $obj->status;
 281         }
 282
 283         function text()
 284         {
 285                 return $this->text;
 286         }
 287 }
 288 ?>