includes/MagicWord.php

   1 <?php
   2
   3 # This class encapsulates "magic words" such as #redirect, __NOTOC__, etc.
   4 # Usage:
   5 #     if (MagicWord::get( MAG_REDIRECT )->match( $text ) )
   6 #
   7 # Possible future improvements:
   8 #   * Simultaneous searching for a number of magic words
   9 #   * $wgMagicWords in shared memory
  10 #
  11 # Please avoid reading the data out of one of these objects and then writing
  12 # special case code. If possible, add another match()-like function here.
  13
  14 /*private*/ $wgMagicFound = false;
  15
  16 define("MAG_REDIRECT", 0);
  17 define("MAG_NOTOC", 1);
  18 define("MAG_START", 2);
  19 define("MAG_CURRENTMONTH", 3);
  20 define("MAG_CURRENTMONTHNAME", 4);
  21 define("MAG_CURRENTDAY", 5);
  22 define("MAG_CURRENTDAYNAME", 6);
  23 define("MAG_CURRENTYEAR", 7);
  24 define("MAG_CURRENTTIME", 8);
  25 define("MAG_NUMBEROFARTICLES", 9);
  26 define("MAG_CURRENTMONTHNAMEGEN", 10);
  27 define("MAG_MSG", 11);
  28 define("MAG_SUBST", 12);
  29 define("MAG_MSGNW", 13);
  30 define("MAG_NOEDITSECTION", 14);
  31 define("MAG_END", 15);
  32 define("MAG_IMG_THUMBNAIL",  16);
  33 define("MAG_IMG_RIGHT",      17);
  34 define("MAG_IMG_LEFT",       18);
  35 define("MAG_IMG_NONE",       19);
  36 define("MAG_IMG_WIDTH",      20);
  37 define("MAG_IMG_CENTER",      21);
  38 define("MAG_INT", 22);
  39 define("MAG_FORCETOC", 23);
  40 define("MAG_SITENAME", 24);
  41 define("MAG_NS", 25);
  42 define("MAG_LOCALURL", 26);
  43 define("MAG_LOCALURLE", 27);
  44 define("MAG_SERVER", 28);
  45 define("MAG_IMG_FRAMED", 29);
  46
  47 $wgVariableIDs = array(
  48         MAG_CURRENTMONTH,
  49         MAG_CURRENTMONTHNAME,
  50         MAG_CURRENTDAY,
  51         MAG_CURRENTDAYNAME,
  52         MAG_CURRENTYEAR,
  53         MAG_CURRENTTIME,
  54         MAG_NUMBEROFARTICLES,
  55         MAG_CURRENTMONTHNAMEGEN,
  56     MAG_SITENAME,
  57         MAG_SERVER
  58 );
  59
  60 class MagicWord {
  61         /*private*/ var $mId, $mSynonyms, $mCaseSensitive, $mRegex;
  62         /*private*/ var $mRegexStart, $mBaseRegex, $mVariableRegex;
  63         /*private*/ var $mModified;
  64
  65         function MagicWord($id = 0, $syn = "", $cs = false)
  66         {
  67                 $this->mId = $id;
  68                 $this->mSynonyms = (array)$syn;
  69                 $this->mCaseSensitive = $cs;
  70                 $this->mRegex = "";
  71                 $this->mRegexStart = "";
  72                 $this->mVariableRegex = "";
  73                 $this->mVariableStartToEndRegex = "";
  74                 $this->mModified = false;
  75         }
  76
  77         # Factory: creates an object representing an ID
  78         /*static*/ function &get( $id )
  79         {
  80                 global $wgMagicWords;
  81
  82                 if (!array_key_exists( $id, $wgMagicWords ) ) {
  83                         $mw = new MagicWord();
  84                         $mw->load( $id );
  85                         $wgMagicWords[$id] = $mw;
  86                 }
  87                 return $wgMagicWords[$id];
  88         }
  89
  90         # Initialises this object with an ID
  91         function load( $id )
  92         {
  93                 global $wgLang;
  94                 $this->mId = $id;
  95                 $wgLang->getMagic( $this );
  96         }
  97
  98         # Preliminary initialisation
  99         /* private */ function initRegex()
 100         {
 101                 $variableClass = Title::legalChars();
 102                 $escSyn = array_map( "preg_quote", $this->mSynonyms );
 103                 $this->mBaseRegex = implode( "|", $escSyn );
 104                 $case = $this->mCaseSensitive ? "" : "i";
 105                 $this->mRegex = "/{$this->mBaseRegex}/{$case}";
 106                 $this->mRegexStart = "/^{$this->mBaseRegex}/{$case}";
 107                 $this->mVariableRegex = str_replace( "\\$1", "([$variableClass]*?)", $this->mRegex );
 108                 $this->mVariableStartToEndRegex = str_replace( "\\$1", "([$variableClass]*?)",
 109                         "/^{$this->mBaseRegex}$/{$case}" );
 110         }
 111
 112         # Gets a regex representing matching the word
 113         function getRegex()
 114         {
 115                 if ($this->mRegex == "" ) {
 116                         $this->initRegex();
 117                 }
 118                 return $this->mRegex;
 119         }
 120
 121         # Gets a regex matching the word, if it is at the
 122         # string start
 123         function getRegexStart()
 124         {
 125                 if ($this->mRegex == "" ) {
 126                         $this->initRegex();
 127                 }
 128                 return $this->mRegexStart;
 129         }
 130
 131         # regex without the slashes and what not
 132         function getBaseRegex()
 133         {
 134                 if ($this->mRegex == "") {
 135                         $this->initRegex();
 136                 }
 137                 return $this->mBaseRegex;
 138         }
 139
 140         # Returns true if the text contains the word
 141         function match( $text ) {
 142                 return preg_match( $this->getRegex(), $text );
 143         }
 144
 145         # Returns true if the text starts with the word
 146         function matchStart( $text )
 147         {
 148                 return preg_match( $this->getRegexStart(), $text );
 149         }
 150
 151         # Returns NULL if there's no match, the value of $1 otherwise
 152         # The return code is the matched string, if there's no variable
 153         # part in the regex and the matched variable part ($1) if there
 154         # is one.
 155         function matchVariableStartToEnd( $text ) {
 156                 $matchcount = preg_match( $this->getVariableStartToEndRegex(), $text, $matches );
 157                 if ( $matchcount == 0 ) {
 158                         return NULL;
 159                 } elseif ( count($matches) == 1 ) {
 160                         return $matches[0];
 161                 } else {
 162                         return $matches[1];
 163                 }
 164         }
 165
 166
 167         # Returns true if the text matches the word, and alters the
 168         # input string, removing all instances of the word
 169         function matchAndRemove( &$text )
 170         {
 171                 global $wgMagicFound;
 172                 $wgMagicFound = false;
 173                 $text = preg_replace_callback( $this->getRegex(), "pregRemoveAndRecord", $text );
 174                 return $wgMagicFound;
 175         }
 176
 177         function matchStartAndRemove( &$text ) {
 178                 global $wgMagicFound;
 179                 $wgMagicFound = false;
 180                 $text = preg_replace_callback( $this->getRegexStart(), "pregRemoveAndRecord", $text );
 181                 return $wgMagicFound;
 182         }
 183
 184
 185         # Replaces the word with something else
 186         function replace( $replacement, $subject )
 187         {
 188                 $res = preg_replace( $this->getRegex(), $replacement, $subject );
 189                 $this->mModified = !($res === $subject);
 190                 return $res;
 191         }
 192
 193         # Variable handling: {{SUBST:xxx}} style words
 194         # Calls back a function to determine what to replace xxx with
 195         # Input word must contain $1
 196         function substituteCallback( $text, $callback ) {
 197                 $regex = $this->getVariableRegex();
 198                 $res = preg_replace_callback( $this->getVariableRegex(), $callback, $text );
 199                 $this->mModified = !($res === $text);
 200                 return $res;
 201         }
 202
 203         # Matches the word, where $1 is a wildcard
 204         function getVariableRegex()
 205         {
 206                 if ( $this->mVariableRegex == "" ) {
 207                         $this->initRegex();
 208                 }
 209                 return $this->mVariableRegex;
 210         }
 211
 212         # Matches the entire string, where $1 is a wildcard
 213         function getVariableStartToEndRegex()
 214         {
 215                 if ( $this->mVariableStartToEndRegex == "" ) {
 216                         $this->initRegex();
 217                 }
 218                 return $this->mVariableStartToEndRegex;
 219         }
 220
 221         # Accesses the synonym list directly
 222         function getSynonym( $i ) {
 223                 return $this->mSynonyms[$i];
 224         }
 225
 226         # Returns true if the last call to replace() or substituteCallback()
 227         # returned a modified text, otherwise false.
 228         function getWasModified(){
 229                 return $this->mModified;
 230         }
 231
 232         # $magicarr is an associative array of (magic word ID => replacement)
 233         # This method uses the php feature to do several replacements at the same time,
 234         # thereby gaining some efficiency. The result is placed in the out variable
 235         # $result. The return value is true if something was replaced.
 236
 237         /* static */ function replaceMultiple( $magicarr, $subject, &$result ){
 238                 $search = array();
 239                 $replace = array();
 240                 foreach( $magicarr as $id => $replacement ){
 241                         $mw = MagicWord::get( $id );
 242                         $search[] = $mw->getRegex();
 243                         $replace[] = $replacement;
 244                 }
 245
 246                 $result = preg_replace( $search, $replace, $subject );
 247                 return !($result === $subject);
 248         }
 249
 250         # Adds all the synonyms of this MagicWord to an array, to allow quick lookup in a list of magic words
 251         function addToArray( &$array, $value )
 252         {
 253                 foreach ( $this->mSynonyms as $syn ) {
 254                         $array[$syn] = $value;
 255                 }
 256         }
 257 }
 258
 259 # Used in matchAndRemove()
 260 /*private*/ function pregRemoveAndRecord( $match )
 261 {
 262         global $wgMagicFound;
 263         $wgMagicFound = true;
 264         return "";
 265 }
 266
 267 ?>