includes/Message.php

   1 <?php
   2 /**
   3  * This class provides methods for fetching interface messages and
   4  * processing them into variety of formats that are needed in MediaWiki.
   5  *
   6  * It is intented to replace the old wfMsg* functions that over time grew
   7  * unusable.
   8  *
   9  * Examples:
  10  * Fetching a message text for interface message
  11  *    $button = Xml::button( wfMessage( 'submit' )->text() );
  12  * </pre>
  13  * Messages can have parameters:
  14  *    wfMessage( 'welcome-to' )->params( $wgSitename )->text();
  15  *        {{GRAMMAR}} and friends work correctly
  16  *    wfMessage( 'are-friends', $user, $friend );
  17  *    wfMessage( 'bad-message' )->rawParams( '<script>...</script>' )->escaped();
  18  * </pre>
  19  * Sometimes the message text ends up in the database, so content language is needed.
  20  *    wfMessage( 'file-log', $user, $filename )->inContentLanguage()->text()
  21  * </pre>
  22  * Checking if message exists:
  23  *    wfMessage( 'mysterious-message' )->exists()
  24  * </pre>
  25  * If you want to use a different language:
  26  *    wfMessage( 'email-header' )->inLanguage( $user->getOption( 'language' ) )->plain()
  27  *        Note that you cannot parse the text except in the content or interface
  28  *        languages
  29  * </pre>
  30  *
  31  *
  32  * Comparison with old wfMsg* functions:
  33  *
  34  * Use full parsing.
  35  *     wfMsgExt( 'key', array( 'parseinline' ), 'apple' );
  36  *     === wfMessage( 'key', 'apple' )->parse();
  37  * </pre>
  38  * Parseinline is used because it is more useful when pre-building html.
  39  * In normal use it is better to use OutputPage::(add|wrap)WikiMsg.
  40  *
  41  * Places where html cannot be used. {{-transformation is done.
  42  *     wfMsgExt( 'key', array( 'parsemag' ), 'apple', 'pear' );
  43  *     === wfMessage( 'key', 'apple', 'pear' )->text();
  44  * </pre>
  45  *
  46  * Shortcut for escaping the message too, similar to wfMsgHTML, but
  47  * parameters are not replaced after escaping by default.
  48  * $escaped = wfMessage( 'key' )->rawParams( 'apple' )->escaped();
  49  * </pre>
  50  *
  51  * TODO:
  52  * - test, can we have tests?
  53  * - sort out the details marked with fixme
  54  *
  55  * @since 1.17
  56  * @author Niklas Laxström
  57  */
  58 class Message {
  59         /**
  60          * In which language to get this message. True, which is the default,
  61          * means the current interface language, false content language.
  62          */
  63         protected $interface = true;
  64
  65         /**
  66          * In which language to get this message. Overrides the $interface
  67          * variable.
  68          */
  69         protected $language = null;
  70
  71         /**
  72          * The message key.
  73          */
  74         protected $key;
  75
  76         /**
  77          * List of parameters which will be substituted into the message.
  78          */
  79         protected $parameters = array();
  80
  81         /**
  82          * Format for the message.
  83          * Supported formats are:
  84          * * text (transform)
  85          * * escaped (transform+htmlspecialchars)
  86          * * block-parse
  87          * * parse (default)
  88          * * plain
  89          */
  90         protected $format = 'parse';
  91
  92         /**
  93          * Whether database can be used.
  94          */
  95         protected $useDatabase = true;
  96
  97         /**
  98          * Constructor.
  99          * @param $key String: message key
 100          * @param $params Array message parameters
 101          * @return Message: $this
 102          */
 103         public function __construct( $key, $params = array() ) {
 104                 global $wgLang;
 105                 $this->key = $key;
 106                 $this->parameters = array_values( $params );
 107                 $this->language = $wgLang;
 108         }
 109
 110         /**
 111          * Factory function that is just wrapper for the real constructor. It is
 112          * intented to be used instead of the real constructor, because it allows
 113          * chaining method calls, while new objects don't.
 114          * @param $key String: message key
 115          * @param Varargs: parameters as Strings
 116          * @return Message: $this
 117          */
 118         public static function newFromKey( $key /*...*/ ) {
 119                 $params = func_get_args();
 120                 array_shift( $params );
 121                 return new self( $key, $params );
 122         }
 123
 124         /**
 125          * Adds parameters to the parameter list of this message.
 126          * @param Varargs: parameters as Strings
 127          * @return Message: $this
 128          */
 129         public function params( /*...*/ ) {
 130                 $args_values = array_values( func_get_args() );
 131                 $this->parameters = array_merge( $this->parameters, $args_values );
 132                 return $this;
 133         }
 134
 135         /**
 136          * Add parameters that are substituted after parsing or escaping.
 137          * In other words the parsing process cannot access the contents
 138          * of this type of parameter, and you need to make sure it is
 139          * sanitized beforehand.  The parser will see "$n", instead.
 140          * @param Varargs: raw parameters as Strings
 141          * @return Message: $this
 142          */
 143         public function rawParams( /*...*/ ) {
 144                 $params = func_get_args();
 145                 foreach( $params as $param ) {
 146                         $this->parameters[] = self::rawParam( $param );
 147                 }
 148                 return $this;
 149         }
 150
 151         /**
 152          * Request the message in any language that is supported.
 153          * As a side effect interface message status is unconditionally
 154          * turned off.
 155          * @param $lang Mixed: language code or Language object.
 156          * @return Message: $this
 157          */
 158         public function inLanguage( $lang ) {
 159                 if( $lang instanceof Language ){
 160                         $this->language = $lang;
 161                 } elseif ( is_string( $lang ) ) {
 162                         if( $this->language->getCode() != $lang ) {
 163                                 $this->language = Language::factory( $lang );
 164                         }
 165                 } else {
 166                         $type = gettype( $lang );
 167                         throw new MWException( __METHOD__ . " must be "
 168                                 . "passed a String or Language object; $type given"
 169                         );
 170                 }
 171                 $this->interface = false;
 172                 return $this;
 173         }
 174
 175         /**
 176          * Request the message in the wiki's content language.
 177          * @return Message: $this
 178          */
 179         public function inContentLanguage() {
 180                 global $wgContLang;
 181                 $this->interface = false;
 182                 $this->language = $wgContLang;
 183                 return $this;
 184         }
 185
 186         /**
 187          * Enable or disable database use.
 188          * @param $value Boolean
 189          * @return Message: $this
 190          */
 191         public function useDatabase( $value ) {
 192                 $this->useDatabase = (bool) $value;
 193                 return $this;
 194         }
 195
 196         /**
 197          * Returns the message parsed from wikitext to HTML.
 198          * TODO: in PHP >= 5.2.0, we can make this a magic method,
 199          * and then we can do, eg:
 200          *     $foo = Message::get($key);
 201          *     $string = "<abbr>$foo</abbr>";
 202          * But we shouldn't implement that while MediaWiki still supports
 203          * PHP < 5.2; or people will start using it...
 204          * @return String: HTML
 205          */
 206         public function toString() {
 207                 $string = $this->getMessageText();
 208
 209                 # Replace parameters before text parsing
 210                 $string = $this->replaceParameters( $string, 'before' );
 211
 212                 # Maybe transform using the full parser
 213                 if( $this->format === 'parse' ) {
 214                         $string = $this->parseText( $string );
 215                         $m = array();
 216                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 217                                 $string = $m[1];
 218                         }
 219                 } elseif( $this->format === 'block-parse' ){
 220                         $string = $this->parseText( $string );
 221                 } elseif( $this->format === 'text' ){
 222                         $string = $this->transformText( $string );
 223                 } elseif( $this->format === 'escaped' ){
 224                         # FIXME: Sanitizer method here?
 225                         $string = $this->transformText( $string );
 226                         $string = htmlspecialchars( $string );
 227                 }
 228
 229                 # Raw parameter replacement
 230                 $string = $this->replaceParameters( $string, 'after' );
 231
 232                 return $string;
 233         }
 234
 235         /**
 236          * Fully parse the text from wikitext to HTML
 237          * @return String parsed HTML
 238          */
 239         public function parse() {
 240                 $this->format = 'parse';
 241                 return $this->toString();
 242         }
 243
 244         /**
 245          * Returns the message text. {{-transformation is done.
 246          * @return String: Unescaped message text.
 247          */
 248         public function text() {
 249                 $this->format = 'text';
 250                 return $this->toString();
 251         }
 252
 253         /**
 254          * Returns the message text as-is, only parameters are subsituted.
 255          * @return String: Unescaped untransformed message text.
 256          */
 257         public function plain() {
 258                 $this->format = 'plain';
 259                 return $this->toString();
 260         }
 261
 262         /**
 263          * Returns the parsed message text which is always surrounded by a block element.
 264          * @return String: HTML
 265          */
 266         public function parseAsBlock() {
 267                 $this->format = 'block-parse';
 268                 return $this->toString();
 269         }
 270
 271         /**
 272          * Returns the message text. {{-transformation is done and the result
 273          * is escaped excluding any raw parameters.
 274          * @return String: Escaped message text.
 275          */
 276         public function escaped() {
 277                 $this->format = 'escaped';
 278                 return $this->toString();
 279         }
 280
 281         /**
 282          * Check whether a message key has been defined currently.
 283          * @return Bool: true if it is and false if not.
 284          */
 285         public function exists() {
 286                 return $this->fetchMessage() !== false;
 287         }
 288
 289         public static function rawParam( $value ) {
 290                 return array( 'raw' => $value );
 291         }
 292
 293         /**
 294          * Substitutes any paramaters into the message text.
 295          * @param $message String, the message text
 296          * @param $type String: either before or after
 297          * @return String
 298          */
 299         protected function replaceParameters( $message, $type = 'before' ) {
 300                 $replacementKeys = array();
 301                 foreach( $this->parameters as $n => $param ) {
 302                         if ( $type === 'before' && !is_array( $param ) ) {
 303                                 $replacementKeys['$' . ($n + 1)] = $param;
 304                         } elseif ( $type === 'after' && isset( $param['raw'] ) ) {
 305                                 $replacementKeys['$' . ($n + 1)] = $param['raw'];
 306                         }
 307                 }
 308                 $message = strtr( $message, $replacementKeys );
 309                 return $message;
 310         }
 311
 312         /**
 313          * Wrapper for what ever method we use to parse wikitext.
 314          * @param $string String: Wikitext message contents
 315          * @return Wikitext parsed into HTML
 316          */
 317         protected function parseText( $string ) {
 318                 global $wgOut;
 319                 return $wgOut->parse( $string, /*linestart*/true, $this->interface, $this->language );
 320         }
 321
 322         /**
 323          * Wrapper for what ever method we use to {{-transform wikitext.
 324          * @param $string String: Wikitext message contents
 325          * @return Wikitext with {{-constructs replaced with their values.
 326          */
 327         protected function transformText( $string ) {
 328                 global $wgMessageCache;
 329                 return $wgMessageCache->transform( $string, $this->interface, $this->language );
 330         }
 331
 332         /**
 333          * Returns the textual value for the message.
 334          * @return Message contents or placeholder
 335          */
 336         protected function getMessageText() {
 337                 $message = $this->fetchMessage();
 338                 if ( $message === false ) {
 339                         return '&lt;' . htmlspecialchars( $this->key ) . '&gt;';
 340                 } else {
 341                         return $message;
 342                 }
 343         }
 344
 345         /**
 346          * Wrapper for what ever method we use to get message contents
 347          */
 348         protected function fetchMessage() {
 349                 if ( !isset( $this->message ) ) {
 350                         global $wgMessageCache;
 351                         $this->message = $wgMessageCache->get( $this->key, $this->useDatabase, $this->language );
 352                 }
 353                 return $this->message;
 354         }
 355
 356 }