includes/MagicWord.php

   1 <?
   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 class MagicWord {
  17         /*private*/ var $mId, $mSynonyms, $mCaseSensitive, $mRegex;
  18         /*private*/ var $mRegexStart, $mBaseRegex, $mVariableRegex;
  19
  20         function MagicWord($id = 0, $syn = "", $cs = false)
  21         {
  22                 $this->mId = $id;
  23                 $this->mSynonyms = (array)$syn;
  24                 $this->mCaseSensitive = $cs;
  25                 $this->mRegex = "";
  26                 $this->mRegexStart = "";
  27                 $this->mVariableRegex = "";
  28         }
  29
  30         # Factory: creates an object representing an ID
  31         /*static*/ function &get( $id )
  32         {
  33                 global $wgMagicWords;
  34
  35                 if (!array_key_exists( $id, $wgMagicWords ) ) {
  36                         $mw = new MagicWord();
  37                         $mw->load( $id );
  38                         $wgMagicWords[$id] = $mw;
  39                 }
  40                 return $wgMagicWords[$id];
  41         }
  42
  43         # Initialises this object with an ID
  44         function load( $id )
  45         {
  46                 global $wgLang;
  47
  48                 $this->mId = $id;
  49                 $wgLang->getMagic( $this );
  50         }
  51
  52         # Preliminary initialisation
  53         /* private */ function initRegex()
  54         {
  55                 $escSyn = array_map( "preg_quote", $this->mSynonyms );
  56                 $this->mBaseRegex = implode( "|", $escSyn );
  57                 $case = $this->mCaseSensitive ? "" : "i";
  58                 $this->mRegex = "/{$this->mBaseRegex}/{$case}";
  59                 $this->mRegexStart = "/^{$this->mBaseRegex}/{$case}";
  60                 $this->mVariableRegex = str_replace( "\\$1", "([A-Za-z0-9_\-]*)", $this->mRegex );
  61         }
  62
  63         # Gets a regex representing matching the word
  64         function getRegex()
  65         {
  66                 if ($this->mRegex == "" ) {
  67                         $this->initRegex();
  68                 }
  69                 return $this->mRegex;
  70         }
  71
  72         # Gets a regex matching the word, if it is at the
  73         # string start
  74         function getRegexStart()
  75         {
  76                 if ($this->mRegex == "" ) {
  77                         $this->initRegex();
  78                 }
  79                 return $this->mRegexStart;
  80         }
  81
  82         # regex without the slashes and what not
  83         function getBaseRegex()
  84         {
  85                 if ($this->mRegex == "") {
  86                         $this->initRegex();
  87                 }
  88                 return $this->mBaseRegex;
  89         }
  90
  91         # Returns true if the text contains the word
  92         function match( $text ) {
  93                 return preg_match( $this->getRegex(), $text );
  94         }
  95
  96         # Returns true if the text starts with the word
  97         function matchStart( $text )
  98         {
  99                 return preg_match( $this->getRegexStart(), $text );
 100         }
 101
 102         # Returns true if the text matches the word, and alters the
 103         # input string, removing all instances of the word
 104         function matchAndRemove( &$text )
 105         {
 106                 global $wgMagicFound;
 107                 $wgMagicFound = false;
 108                 $text = preg_replace_callback( $this->getRegex(), "pregRemoveAndRecord", $text );
 109                 return $wgMagicFound;
 110         }
 111
 112         # Replaces the word with something else
 113         function replace( $replacement, $subject )
 114         {
 115                 return preg_replace( $this->getRegex(), $replacement, $subject );
 116         }
 117
 118         # Variable handling: {{SUBST:xxx}} style words
 119         # Calls back a function to determine what to replace xxx with
 120         # Input word must contain $1
 121         function substituteCallback( $text, $callback ) {
 122                 $regex = $this->getVariableRegex();
 123                 return preg_replace_callback( $this->getVariableRegex(), $callback, $text );
 124         }
 125
 126         # Matches the word, where $1 is a wildcard
 127         function getVariableRegex()
 128         {
 129                 if ( $this->mVariableRegex == "" ) {
 130                         $this->initRegex();
 131                 }
 132                 return $this->mVariableRegex;
 133         }
 134
 135         # Accesses the synonym list directly
 136         function getSynonym( $i ) {
 137                 return $this->mSynonyms[$i];
 138         }
 139 }
 140
 141 # Used in matchAndRemove()
 142 /*private*/ function pregRemoveAndRecord( $match )
 143 {
 144         global $wgMagicFound;
 145         $wgMagicFound = true;
 146         return "";
 147 }
 148
 149 ?>