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 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
  51                 $do_update_diff_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                         $do_update_diff_table .= '<tr>';
  64                         $params = array($_obj->get('left'), $_obj->get('right'), $_obj->text());
  65                         foreach ($params as $key=>$text) {
  66                                 $text = htmlsc($text);
  67                                 if (trim($text) == '') $text = '&nbsp;';
  68                                 $do_update_diff_table .= '<' . $tags[$key] .
  69                                         ' class="style_' . $tags[$key] . '">' . $text .
  70                                         '</' . $tags[$key] . '>';
  71                         }
  72                         $do_update_diff_table .= '</tr>' . "\n";
  73                 }
  74                 $do_update_diff_table .= '</table>' . "\n";
  75         }
  76
  77         $body = '';
  78         foreach ($arr as $_obj) {
  79                 if ($_obj->get('left') != '-' && $_obj->get('right') != '-')
  80                         $body .= $_obj->text();
  81         }
  82
  83         $auto = 1;
  84
  85         return array(rtrim($body) . "\n", $auto);
  86 }
  87
  88
  89 // References of this class:
  90 // S. Wu, <A HREF="http://www.cs.arizona.edu/people/gene/vita.html">
  91 // E. Myers,</A> U. Manber, and W. Miller,
  92 // <A HREF="http://www.cs.arizona.edu/people/gene/PAPERS/np_diff.ps">
  93 // "An O(NP) Sequence Comparison Algorithm,"</A>
  94 // Information Processing Letters 35, 6 (1990), 317-323.
  95 class line_diff
  96 {
  97         var $arr1, $arr2, $m, $n, $pos, $key, $plus, $minus, $equal, $reverse;
  98
  99         function line_diff($plus = '+', $minus = '-', $equal = ' ')
 100         {
 101                 $this->plus  = $plus;
 102                 $this->minus = $minus;
 103                 $this->equal = $equal;
 104         }
 105
 106         function arr_compare($key, $arr1, $arr2)
 107         {
 108                 $this->key  = $key;
 109                 $this->arr1 = $arr1;
 110                 $this->arr2 = $arr2;
 111                 $this->compare();
 112                 $arr = $this->toArray();
 113                 return $arr;
 114         }
 115
 116         function set_str($key, $str1, $str2)
 117         {
 118                 $this->key  = $key;
 119                 $this->arr1 = array();
 120                 $this->arr2 = array();
 121                 $str1 = str_replace("\r", '', $str1);
 122                 $str2 = str_replace("\r", '', $str2);
 123                 foreach (explode("\n", $str1) as $line) {
 124                         $this->arr1[] = new DiffLine($line);
 125                 }
 126                 foreach (explode("\n", $str2) as $line) {
 127                         $this->arr2[] = new DiffLine($line);
 128                 }
 129         }
 130
 131         function str_compare($str1, $str2)
 132         {
 133                 $this->set_str('diff', $str1, $str2);
 134                 $this->compare();
 135
 136                 $str = '';
 137                 foreach ($this->toArray() as $obj) {
 138                         $str .= $obj->get('diff') . $obj->text();
 139                 }
 140                 return $str;
 141         }
 142
 143         function compare()
 144         {
 145                 $this->m = count($this->arr1);
 146                 $this->n = count($this->arr2);
 147
 148                 if ($this->m == 0 || $this->n == 0) { // No need to compare
 149                         $this->result = array(array('x'=>0, 'y'=>0));
 150                         return;
 151                 }
 152
 153                 // Sentinel
 154                 array_unshift($this->arr1, new DiffLine(''));
 155                 $this->m++;
 156                 array_unshift($this->arr2, new DiffLine(''));
 157                 $this->n++;
 158
 159                 $this->reverse = ($this->n < $this->m);
 160                 if ($this->reverse) {
 161                         // Swap
 162                         $tmp = $this->m; $this->m = $this->n; $this->n = $tmp;
 163                         $tmp = $this->arr1; $this->arr1 = $this->arr2; $this->arr2 = $tmp;
 164                         unset($tmp);
 165                 }
 166
 167                 $delta = $this->n - $this->m; // Must be >=0;
 168
 169                 $fp = array();
 170                 $this->path = array();
 171
 172                 for ($p = -($this->m + 1); $p <= ($this->n + 1); $p++) {
 173                         $fp[$p] = -1;
 174                         $this->path[$p] = array();
 175                 }
 176
 177                 for ($p = 0;; $p++) {
 178                         for ($k = -$p; $k <= $delta - 1; $k++) {
 179                                 $fp[$k] = $this->snake($k, $fp[$k - 1], $fp[$k + 1]);
 180                         }
 181                         for ($k = $delta + $p; $k >= $delta + 1; $k--) {
 182                                 $fp[$k] = $this->snake($k, $fp[$k - 1], $fp[$k + 1]);
 183                         }
 184                         $fp[$delta] = $this->snake($delta, $fp[$delta - 1], $fp[$delta + 1]);
 185                         if ($fp[$delta] >= $this->n) {
 186                                 $this->pos = $this->path[$delta]; // ·ÐÏ©¤ò·èÄê
 187                                 return;
 188                         }
 189                 }
 190         }
 191
 192         function snake($k, $y1, $y2)
 193         {
 194                 if ($y1 >= $y2) {
 195                         $_k = $k - 1;
 196                         $y = $y1 + 1;
 197                 } else {
 198                         $_k = $k + 1;
 199                         $y = $y2;
 200                 }
 201                 $this->path[$k] = $this->path[$_k];// ¤³¤³¤Þ¤Ç¤Î·ÐÏ©¤ò¥³¥Ô¡¼
 202                 $x = $y - $k;
 203                 while ((($x + 1) < $this->m) && (($y + 1) < $this->n)
 204                         and $this->arr1[$x + 1]->compare($this->arr2[$y + 1]))
 205                 {
 206                         ++$x; ++$y;
 207                         $this->path[$k][] = array('x'=>$x, 'y'=>$y); // ·ÐÏ©¤òÄÉ²Ã
 208                 }
 209                 return $y;
 210         }
 211
 212         function toArray()
 213         {
 214                 $arr = array();
 215                 if ($this->reverse) { // ¸ÈÂ©¤Ê¡Ä
 216                         $_x = 'y'; $_y = 'x'; $_m = $this->n; $arr1 =& $this->arr2; $arr2 =& $this->arr1;
 217                 } else {
 218                         $_x = 'x'; $_y = 'y'; $_m = $this->m; $arr1 =& $this->arr1; $arr2 =& $this->arr2;
 219                 }
 220
 221                 $x = $y = 1;
 222                 $this->add_count = $this->delete_count = 0;
 223                 $this->pos[] = array('x'=>$this->m, 'y'=>$this->n); // Sentinel
 224                 foreach ($this->pos as $pos) {
 225                         $this->delete_count += ($pos[$_x] - $x);
 226                         $this->add_count    += ($pos[$_y] - $y);
 227
 228                         while ($pos[$_x] > $x) {
 229                                 $arr1[$x]->set($this->key, $this->minus);
 230                                 $arr[] = $arr1[$x++];
 231                         }
 232
 233                         while ($pos[$_y] > $y) {
 234                                 $arr2[$y]->set($this->key, $this->plus);
 235                                 $arr[] =  $arr2[$y++];
 236                         }
 237
 238                         if ($x < $_m) {
 239                                 $arr1[$x]->merge($arr2[$y]);
 240                                 $arr1[$x]->set($this->key, $this->equal);
 241                                 $arr[] = $arr1[$x];
 242                         }
 243                         ++$x; ++$y;
 244                 }
 245                 return $arr;
 246         }
 247 }
 248
 249 class DiffLine
 250 {
 251         var $text;
 252         var $status;
 253
 254         function DiffLine($text)
 255         {
 256                 $this->text   = $text . "\n";
 257                 $this->status = array();
 258         }
 259
 260         function compare($obj)
 261         {
 262                 return $this->text == $obj->text;
 263         }
 264
 265         function set($key, $status)
 266         {
 267                 $this->status[$key] = $status;
 268         }
 269
 270         function get($key)
 271         {
 272                 return isset($this->status[$key]) ? $this->status[$key] : '';
 273         }
 274
 275         function merge($obj)
 276         {
 277                 $this->status += $obj->status;
 278         }
 279
 280         function text()
 281         {
 282                 return $this->text;
 283         }
 284 }
 285 ?>