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