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  *
  54  * @since 1.17
  55  * @author Niklas Laxström
  56  */
  57 class Message {
  58         /**
  59          * In which language to get this message. True, which is the default,
  60          * means the current interface language, false content language.
  61          */
  62         protected $interface = true;
  63
  64         /**
  65          * In which language to get this message. Overrides the $interface
  66          * variable.
  67          *
  68          * @var Language
  69          */
  70         protected $language = null;
  71
  72         /**
  73          * The message key.
  74          */
  75         protected $key;
  76
  77         /**
  78          * List of parameters which will be substituted into the message.
  79          */
  80         protected $parameters = array();
  81
  82         /**
  83          * Format for the message.
  84          * Supported formats are:
  85          * * text (transform)
  86          * * escaped (transform+htmlspecialchars)
  87          * * block-parse
  88          * * parse (default)
  89          * * plain
  90          */
  91         protected $format = 'parse';
  92
  93         /**
  94          * Whether database can be used.
  95          */
  96         protected $useDatabase = true;
  97
  98         /**
  99          * Title object to use as context
 100          */
 101         protected $title = null;
 102
 103         /**
 104          * @var string
 105          */
 106         protected $message;
 107
 108         /**
 109          * Constructor.
 110          * @param $key: message key, or array of message keys to try and use the first non-empty message for
 111          * @param $params Array message parameters
 112          * @return Message: $this
 113          */
 114         public function __construct( $key, $params = array() ) {
 115                 global $wgLang;
 116                 $this->key = $key;
 117                 $this->parameters = array_values( $params );
 118                 $this->language = $wgLang;
 119         }
 120
 121         /**
 122          * Factory function that is just wrapper for the real constructor. It is
 123          * intented to be used instead of the real constructor, because it allows
 124          * chaining method calls, while new objects don't.
 125          * @param $key String: message key
 126          * @param Varargs: parameters as Strings
 127          * @return Message: $this
 128          */
 129         public static function newFromKey( $key /*...*/ ) {
 130                 $params = func_get_args();
 131                 array_shift( $params );
 132                 return new self( $key, $params );
 133         }
 134
 135         /**
 136          * Factory function accepting multiple message keys and returning a message instance
 137          * for the first message which is non-empty. If all messages are empty then an
 138          * instance of the first message key is returned.
 139          * @param Varargs: message keys
 140          * @return Message: $this
 141          */
 142         public static function newFallbackSequence( /*...*/ ) {
 143                 $keys = func_get_args();
 144                 if ( func_num_args() == 1 ) {
 145                         if ( is_array($keys[0]) ) {
 146                                 // Allow an array to be passed as the first argument instead
 147                                 $keys = array_values($keys[0]);
 148                         } else {
 149                                 // Optimize a single string to not need special fallback handling
 150                                 $keys = $keys[0];
 151                         }
 152                 }
 153                 return new self( $keys );
 154         }
 155
 156         /**
 157          * Adds parameters to the parameter list of this message.
 158          * @param Varargs: parameters as Strings
 159          * @return Message: $this
 160          */
 161         public function params( /*...*/ ) {
 162                 $args = func_get_args();
 163                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 164                         $args = $args[0];
 165                 }
 166                 $args_values = array_values( $args );
 167                 $this->parameters = array_merge( $this->parameters, $args_values );
 168                 return $this;
 169         }
 170
 171         /**
 172          * Add parameters that are substituted after parsing or escaping.
 173          * In other words the parsing process cannot access the contents
 174          * of this type of parameter, and you need to make sure it is
 175          * sanitized beforehand.  The parser will see "$n", instead.
 176          * @param Varargs: raw parameters as Strings
 177          * @return Message: $this
 178          */
 179         public function rawParams( /*...*/ ) {
 180                 $params = func_get_args();
 181                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 182                         $params = $params[0];
 183                 }
 184                 foreach( $params as $param ) {
 185                         $this->parameters[] = self::rawParam( $param );
 186                 }
 187                 return $this;
 188         }
 189
 190         /**
 191          * Add parameters that are numeric and will be passed through
 192          * Language::formatNum before substitution
 193          * @param Varargs: numeric parameters
 194          * @return Message: $this
 195          */
 196         public function numParams( /*...*/ ) {
 197                 $params = func_get_args();
 198                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 199                         $params = $params[0];
 200                 }
 201                 foreach( $params as $param ) {
 202                         $this->parameters[] = self::numParam( $param );
 203                 }
 204                 return $this;
 205         }
 206
 207         /**
 208          * Request the message in any language that is supported.
 209          * As a side effect interface message status is unconditionally
 210          * turned off.
 211          * @param $lang Mixed: language code or Language object.
 212          * @return Message: $this
 213          */
 214         public function inLanguage( $lang ) {
 215                 if ( $lang instanceof Language || $lang instanceof StubUserLang ) {
 216                         $this->language = $lang;
 217                 } elseif ( is_string( $lang ) ) {
 218                         if( $this->language->getCode() != $lang ) {
 219                                 $this->language = Language::factory( $lang );
 220                         }
 221                 } else {
 222                         $type = gettype( $lang );
 223                         throw new MWException( __METHOD__ . " must be "
 224                                 . "passed a String or Language object; $type given"
 225                         );
 226                 }
 227                 $this->interface = false;
 228                 return $this;
 229         }
 230
 231         /**
 232          * Request the message in the wiki's content language,
 233          * unless it is disabled for this message.
 234          * @see $wgForceUIMsgAsContentMsg
 235          * @return Message: $this
 236          */
 237         public function inContentLanguage() {
 238                 global $wgForceUIMsgAsContentMsg;
 239                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 240                         return $this;
 241                 }
 242
 243                 global $wgContLang;
 244                 $this->interface = false;
 245                 $this->language = $wgContLang;
 246                 return $this;
 247         }
 248
 249         /**
 250          * Enable or disable database use.
 251          * @param $value Boolean
 252          * @return Message: $this
 253          */
 254         public function useDatabase( $value ) {
 255                 $this->useDatabase = (bool) $value;
 256                 return $this;
 257         }
 258
 259         /**
 260          * Set the Title object to use as context when transforming the message
 261          *
 262          * @param $title Title object
 263          * @return Message: $this
 264          */
 265         public function title( $title ) {
 266                 $this->title = $title;
 267                 return $this;
 268         }
 269
 270         /**
 271          * Returns the message parsed from wikitext to HTML.
 272          * @return String: HTML
 273          */
 274         public function toString() {
 275                 $string = $this->getMessageText();
 276
 277                 # Replace parameters before text parsing
 278                 $string = $this->replaceParameters( $string, 'before' );
 279
 280                 # Maybe transform using the full parser
 281                 if( $this->format === 'parse' ) {
 282                         $string = $this->parseText( $string );
 283                         $m = array();
 284                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 285                                 $string = $m[1];
 286                         }
 287                 } elseif( $this->format === 'block-parse' ){
 288                         $string = $this->parseText( $string );
 289                 } elseif( $this->format === 'text' ){
 290                         $string = $this->transformText( $string );
 291                 } elseif( $this->format === 'escaped' ){
 292                         $string = $this->transformText( $string );
 293                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 294                 }
 295
 296                 # Raw parameter replacement
 297                 $string = $this->replaceParameters( $string, 'after' );
 298
 299                 return $string;
 300         }
 301
 302         /**
 303          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 304          *     $foo = Message::get($key);
 305          *     $string = "<abbr>$foo</abbr>";
 306          * @return String
 307          */
 308         public function __toString() {
 309                 return $this->toString();
 310         }
 311
 312         /**
 313          * Fully parse the text from wikitext to HTML
 314          * @return String parsed HTML
 315          */
 316         public function parse() {
 317                 $this->format = 'parse';
 318                 return $this->toString();
 319         }
 320
 321         /**
 322          * Returns the message text. {{-transformation is done.
 323          * @return String: Unescaped message text.
 324          */
 325         public function text() {
 326                 $this->format = 'text';
 327                 return $this->toString();
 328         }
 329
 330         /**
 331          * Returns the message text as-is, only parameters are subsituted.
 332          * @return String: Unescaped untransformed message text.
 333          */
 334         public function plain() {
 335                 $this->format = 'plain';
 336                 return $this->toString();
 337         }
 338
 339         /**
 340          * Returns the parsed message text which is always surrounded by a block element.
 341          * @return String: HTML
 342          */
 343         public function parseAsBlock() {
 344                 $this->format = 'block-parse';
 345                 return $this->toString();
 346         }
 347
 348         /**
 349          * Returns the message text. {{-transformation is done and the result
 350          * is escaped excluding any raw parameters.
 351          * @return String: Escaped message text.
 352          */
 353         public function escaped() {
 354                 $this->format = 'escaped';
 355                 return $this->toString();
 356         }
 357
 358         /**
 359          * Check whether a message key has been defined currently.
 360          * @return Bool: true if it is and false if not.
 361          */
 362         public function exists() {
 363                 return $this->fetchMessage() !== false;
 364         }
 365
 366         /**
 367          * Check whether a message does not exist, or is an empty string
 368          * @return Bool: true if is is and false if not
 369          * @todo FIXME: Merge with isDisabled()?
 370          */
 371         public function isBlank() {
 372                 $message = $this->fetchMessage();
 373                 return $message === false || $message === '';
 374         }
 375
 376         /**
 377          * Check whether a message does not exist, is an empty string, or is "-"
 378          * @return Bool: true if is is and false if not
 379          */
 380         public function isDisabled() {
 381                 $message = $this->fetchMessage();
 382                 return $message === false || $message === '' || $message === '-';
 383         }
 384
 385         /**
 386          * @param $value
 387          * @return array
 388          */
 389         public static function rawParam( $value ) {
 390                 return array( 'raw' => $value );
 391         }
 392
 393         /**
 394          * @param $value
 395          * @return array
 396          */
 397         public static function numParam( $value ) {
 398                 return array( 'num' => $value );
 399         }
 400
 401         /**
 402          * Substitutes any paramaters into the message text.
 403          * @param $message String: the message text
 404          * @param $type String: either before or after
 405          * @return String
 406          */
 407         protected function replaceParameters( $message, $type = 'before' ) {
 408                 $replacementKeys = array();
 409                 foreach( $this->parameters as $n => $param ) {
 410                         list( $paramType, $value ) = $this->extractParam( $param );
 411                         if ( $type === $paramType ) {
 412                                 $replacementKeys['$' . ($n + 1)] = $value;
 413                         }
 414                 }
 415                 $message = strtr( $message, $replacementKeys );
 416                 return $message;
 417         }
 418
 419         /**
 420          * Extracts the parameter type and preprocessed the value if needed.
 421          * @param $param String|Array: Parameter as defined in this class.
 422          * @return Tuple(type, value)
 423          * @throws MWException
 424          */
 425         protected function extractParam( $param ) {
 426                 if ( is_array( $param ) && isset( $param['raw'] ) ) {
 427                         return array( 'after', $param['raw'] );
 428                 } elseif ( is_array( $param ) && isset( $param['num'] ) ) {
 429                         // Replace number params always in before step for now.
 430                         // No support for combined raw and num params
 431                         return array( 'before', $this->language->formatNum( $param['num'] ) );
 432                 } elseif ( !is_array( $param ) ) {
 433                         return array( 'before', $param );
 434                 } else {
 435                         throw new MWException( "Invalid message parameter" );
 436                 }
 437         }
 438
 439         /**
 440          * Wrapper for what ever method we use to parse wikitext.
 441          * @param $string String: Wikitext message contents
 442          * @return string Wikitext parsed into HTML
 443          */
 444         protected function parseText( $string ) {
 445                 return MessageCache::singleton()->parse( $string, $this->title, /*linestart*/true, $this->interface, $this->language )->getText();
 446         }
 447
 448         /**
 449          * Wrapper for what ever method we use to {{-transform wikitext.
 450          * @param $string String: Wikitext message contents
 451          * @return string Wikitext with {{-constructs replaced with their values.
 452          */
 453         protected function transformText( $string ) {
 454                 return MessageCache::singleton()->transform( $string, $this->interface, $this->language, $this->title );
 455         }
 456
 457         /**
 458          * Returns the textual value for the message.
 459          * @return Message contents or placeholder
 460          */
 461         protected function getMessageText() {
 462                 $message = $this->fetchMessage();
 463                 if ( $message === false ) {
 464                         return '&lt;' . htmlspecialchars( is_array($this->key) ? $this->key[0] : $this->key ) . '&gt;';
 465                 } else {
 466                         return $message;
 467                 }
 468         }
 469
 470         /**
 471          * Wrapper for what ever method we use to get message contents
 472          *
 473          * @return string
 474          */
 475         protected function fetchMessage() {
 476                 if ( !isset( $this->message ) ) {
 477                         $cache = MessageCache::singleton();
 478                         if ( is_array($this->key) ) {
 479                                 foreach ( $this->key as $key ) {
 480                                         $message = $cache->get( $key, $this->useDatabase, $this->language );
 481                                         if ( $message !== false && $message !== '' ) {
 482                                                 break;
 483                                         }
 484                                 }
 485                                 $this->message = $message;
 486                         } else {
 487                                 $this->message = $cache->get( $this->key, $this->useDatabase, $this->language );
 488                         }
 489                 }
 490                 return $this->message;
 491         }
 492
 493 }