includes/parser/StripState.php

   1 <?php
   2 /**
   3  * Holder for stripped items when parsing wiki markup.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Parser
  22  */
  23
  24 /**
  25  * @todo document, briefly.
  26  * @ingroup Parser
  27  */
  28 class StripState {
  29         protected $prefix;
  30         protected $data;
  31         protected $regex;
  32
  33         protected $tempType, $tempMergePrefix;
  34         protected $circularRefGuard;
  35         protected $recursionLevel = 0;
  36
  37         const UNSTRIP_RECURSION_LIMIT = 20;
  38
  39         /**
  40          * @param $prefix string
  41          */
  42         function __construct( $prefix ) {
  43                 $this->prefix = $prefix;
  44                 $this->data = array(
  45                         'nowiki' => array(),
  46                         'general' => array()
  47                 );
  48                 $this->regex = "/{$this->prefix}([^\x7f]+)" . Parser::MARKER_SUFFIX . '/';
  49                 $this->circularRefGuard = array();
  50         }
  51
  52         /**
  53          * Add a nowiki strip item
  54          * @param $marker
  55          * @param $value
  56          */
  57         function addNoWiki( $marker, $value ) {
  58                 $this->addItem( 'nowiki', $marker, $value );
  59         }
  60
  61         /**
  62          * @param $marker
  63          * @param $value
  64          */
  65         function addGeneral( $marker, $value ) {
  66                 $this->addItem( 'general', $marker, $value );
  67         }
  68
  69         /**
  70          * @throws MWException
  71          * @param $type
  72          * @param $marker
  73          * @param $value
  74          */
  75         protected function addItem( $type, $marker, $value ) {
  76                 if ( !preg_match( $this->regex, $marker, $m ) ) {
  77                         throw new MWException( "Invalid marker: $marker" );
  78                 }
  79
  80                 $this->data[$type][$m[1]] = $value;
  81         }
  82
  83         /**
  84          * @param $text
  85          * @return mixed
  86          */
  87         function unstripGeneral( $text ) {
  88                 return $this->unstripType( 'general', $text );
  89         }
  90
  91         /**
  92          * @param $text
  93          * @return mixed
  94          */
  95         function unstripNoWiki( $text ) {
  96                 return $this->unstripType( 'nowiki', $text );
  97         }
  98
  99         /**
 100          * @param  $text
 101          * @return mixed
 102          */
 103         function unstripBoth( $text ) {
 104                 $text = $this->unstripType( 'general', $text );
 105                 $text = $this->unstripType( 'nowiki', $text );
 106                 return $text;
 107         }
 108
 109         /**
 110          * @param $type
 111          * @param $text
 112          * @return mixed
 113          */
 114         protected function unstripType( $type, $text ) {
 115                 // Shortcut
 116                 if ( !count( $this->data[$type] ) ) {
 117                         return $text;
 118                 }
 119
 120                 wfProfileIn( __METHOD__ );
 121                 $oldType = $this->tempType;
 122                 $this->tempType = $type;
 123                 $text = preg_replace_callback( $this->regex, array( $this, 'unstripCallback' ), $text );
 124                 $this->tempType = $oldType;
 125                 wfProfileOut( __METHOD__ );
 126                 return $text;
 127         }
 128
 129         /**
 130          * @param $m array
 131          * @return array
 132          */
 133         protected function unstripCallback( $m ) {
 134                 $marker = $m[1];
 135                 if ( isset( $this->data[$this->tempType][$marker] ) ) {
 136                         if ( isset( $this->circularRefGuard[$marker] ) ) {
 137                                 return '<span class="error">' . wfMsgForContent( 'parser-unstrip-loop-warning' ) . '</span>';
 138                         }
 139                         if ( $this->recursionLevel >= self::UNSTRIP_RECURSION_LIMIT ) {
 140                                 return '<span class="error">' .
 141                                         wfMsgForContent( 'parser-unstrip-recursion-limit', self::UNSTRIP_RECURSION_LIMIT ) .
 142                                         '</span>';
 143                         }
 144                         $this->circularRefGuard[$marker] = true;
 145                         $this->recursionLevel++;
 146                         $ret = $this->unstripType( $this->tempType, $this->data[$this->tempType][$marker] );
 147                         $this->recursionLevel--;
 148                         unset( $this->circularRefGuard[$marker] );
 149                         return $ret;
 150                 } else {
 151                         return $m[0];
 152                 }
 153         }
 154
 155         /**
 156          * Get a StripState object which is sufficient to unstrip the given text.
 157          * It will contain the minimum subset of strip items necessary.
 158          *
 159          * @param $text string
 160          *
 161          * @return StripState
 162          */
 163         function getSubState( $text ) {
 164                 $subState = new StripState( $this->prefix );
 165                 $pos = 0;
 166                 while ( true ) {
 167                         $startPos = strpos( $text, $this->prefix, $pos );
 168                         $endPos = strpos( $text, Parser::MARKER_SUFFIX, $pos );
 169                         if ( $startPos === false || $endPos === false ) {
 170                                 break;
 171                         }
 172
 173                         $endPos += strlen( Parser::MARKER_SUFFIX );
 174                         $marker = substr( $text, $startPos, $endPos - $startPos );
 175                         if ( !preg_match( $this->regex, $marker, $m ) ) {
 176                                 continue;
 177                         }
 178
 179                         $key = $m[1];
 180                         if ( isset( $this->data['nowiki'][$key] ) ) {
 181                                 $subState->data['nowiki'][$key] = $this->data['nowiki'][$key];
 182                         } elseif ( isset( $this->data['general'][$key] ) ) {
 183                                 $subState->data['general'][$key] = $this->data['general'][$key];
 184                         }
 185                         $pos = $endPos;
 186                 }
 187                 return $subState;
 188         }
 189
 190         /**
 191          * Merge another StripState object into this one. The strip marker keys
 192          * will not be preserved. The strings in the $texts array will have their
 193          * strip markers rewritten, the resulting array of strings will be returned.
 194          *
 195          * @param $otherState StripState
 196          * @param $texts Array
 197          * @return Array
 198          */
 199         function merge( $otherState, $texts ) {
 200                 $mergePrefix = Parser::getRandomString();
 201
 202                 foreach ( $otherState->data as $type => $items ) {
 203                         foreach ( $items as $key => $value ) {
 204                                 $this->data[$type]["$mergePrefix-$key"] = $value;
 205                         }
 206                 }
 207
 208                 $this->tempMergePrefix = $mergePrefix;
 209                 $texts = preg_replace_callback( $otherState->regex, array( $this, 'mergeCallback' ), $texts );
 210                 $this->tempMergePrefix = null;
 211                 return $texts;
 212         }
 213
 214         /**
 215          * @param $m
 216          * @return string
 217          */
 218         protected function mergeCallback( $m ) {
 219                 $key = $m[1];
 220                 return "{$this->prefix}{$this->tempMergePrefix}-$key" . Parser::MARKER_SUFFIX;
 221         }
 222
 223         /**
 224          * Remove any strip markers found in the given text.
 225          *
 226          * @param $text Input string
 227          * @return string
 228          */
 229         function killMarkers( $text ) {
 230                 return preg_replace( $this->regex, '', $text );
 231         }
 232 }
 233