includes/Message.php

   1 <?php
   2 /**
   3  * Fetching and processing of interface messages.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Niklas Laxström
  22  */
  23
  24 /**
  25  * The Message class provides methods which fulfil two basic services:
  26  *  - fetching interface messages
  27  *  - processing messages into a variety of formats
  28  *
  29  * First implemented with MediaWiki 1.17, the Message class is intended to
  30  * replace the old wfMsg* functions that over time grew unusable.
  31  * @see https://www.mediawiki.org/wiki/Manual:Messages_API for equivalences
  32  * between old and new functions.
  33  *
  34  * You should use the wfMessage() global function which acts as a wrapper for
  35  * the Message class. The wrapper let you pass parameters as arguments.
  36  *
  37  * The most basic usage cases would be:
  38  *
  39  * @code
  40  *     // Initialize a Message object using the 'some_key' message key
  41  *     $message = wfMessage( 'some_key' );
  42  *
  43  *     // Using two parameters those values are strings 'value1' and 'value2':
  44  *     $message = wfMessage( 'some_key',
  45  *          'value1', 'value2'
  46  *     );
  47  * @endcode
  48  *
  49  * @section message_global_fn Global function wrapper:
  50  *
  51  * Since wfMessage() returns a Message instance, you can chain its call with
  52  * a method. Some of them return a Message instance too so you can chain them.
  53  * You will find below several examples of wfMessage() usage.
  54  *
  55  * Fetching a message text for interface message:
  56  *
  57  * @code
  58  *    $button = Xml::button(
  59  *         wfMessage( 'submit' )->text()
  60  *    );
  61  * @endcode
  62  *
  63  * A Message instance can be passed parameters after it has been constructed,
  64  * use the params() method to do so:
  65  *
  66  * @code
  67  *     wfMessage( 'welcome-to' )
  68  *         ->params( $wgSitename )
  69  *         ->text();
  70  * @endcode
  71  *
  72  * {{GRAMMAR}} and friends work correctly:
  73  *
  74  * @code
  75  *    wfMessage( 'are-friends',
  76  *        $user, $friend
  77  *    );
  78  *    wfMessage( 'bad-message' )
  79  *         ->rawParams( '<script>...</script>' )
  80  *         ->escaped();
  81  * @endcode
  82  *
  83  * @section message_language Changing language:
  84  *
  85  * Messages can be requested in a different language or in whatever current
  86  * content language is being used. The methods are:
  87  *     - Message->inContentLanguage()
  88  *     - Message->inLanguage()
  89  *
  90  * Sometimes the message text ends up in the database, so content language is
  91  * needed:
  92  *
  93  * @code
  94  *    wfMessage( 'file-log',
  95  *        $user, $filename
  96  *    )->inContentLanguage()->text();
  97  * @endcode
  98  *
  99  * Checking whether a message exists:
 100  *
 101  * @code
 102  *    wfMessage( 'mysterious-message' )->exists()
 103  *    // returns a boolean whether the 'mysterious-message' key exist.
 104  * @endcode
 105  *
 106  * If you want to use a different language:
 107  *
 108  * @code
 109  *    $userLanguage = $user->getOption( 'language' );
 110  *    wfMessage( 'email-header' )
 111  *         ->inLanguage( $userLanguage )
 112  *         ->plain();
 113  * @endcode
 114  *
 115  * @note You can parse the text only in the content or interface languages
 116  *
 117  * @section message_compare_old Comparison with old wfMsg* functions:
 118  *
 119  * Use full parsing:
 120  *
 121  * @code
 122  *     // old style:
 123  *     wfMsgExt( 'key', array( 'parseinline' ), 'apple' );
 124  *     // new style:
 125  *     wfMessage( 'key', 'apple' )->parse();
 126  * @endcode
 127  *
 128  * Parseinline is used because it is more useful when pre-building HTML.
 129  * In normal use it is better to use OutputPage::(add|wrap)WikiMsg.
 130  *
 131  * Places where HTML cannot be used. {{-transformation is done.
 132  * @code
 133  *     // old style:
 134  *     wfMsgExt( 'key', array( 'parsemag' ), 'apple', 'pear' );
 135  *     // new style:
 136  *     wfMessage( 'key', 'apple', 'pear' )->text();
 137  * @endcode
 138  *
 139  * Shortcut for escaping the message too, similar to wfMsgHTML(), but
 140  * parameters are not replaced after escaping by default.
 141  * @code
 142  *     $escaped = wfMessage( 'key' )
 143  *          ->rawParams( 'apple' )
 144  *          ->escaped();
 145  * @endcode
 146  *
 147  * @section message_appendix Appendix:
 148  *
 149  * @todo
 150  * - test, can we have tests?
 151  * - this documentation needs to be extended
 152  *
 153  * @see https://www.mediawiki.org/wiki/WfMessage()
 154  * @see https://www.mediawiki.org/wiki/New_messages_API
 155  * @see https://www.mediawiki.org/wiki/Localisation
 156  *
 157  * @since 1.17
 158  */
 159 class Message implements MessageSpecifier {
 160
 161         /**
 162          * In which language to get this message. True, which is the default,
 163          * means the current interface language, false content language.
 164          *
 165          * @var bool
 166          */
 167         protected $interface = true;
 168
 169         /**
 170          * In which language to get this message. Overrides the $interface
 171          * variable.
 172          *
 173          * @var Language
 174          */
 175         protected $language = null;
 176
 177         /**
 178          * @var string The message key. If $keysToTry has more than one element,
 179          * this may change to one of the keys to try when fetching the message text.
 180          */
 181         protected $key;
 182
 183         /**
 184          * @var string[] List of keys to try when fetching the message.
 185          */
 186         protected $keysToTry;
 187
 188         /**
 189          * @var array List of parameters which will be substituted into the message.
 190          */
 191         protected $parameters = array();
 192
 193         /**
 194          * Format for the message.
 195          * Supported formats are:
 196          * * text (transform)
 197          * * escaped (transform+htmlspecialchars)
 198          * * block-parse
 199          * * parse (default)
 200          * * plain
 201          *
 202          * @var string
 203          */
 204         protected $format = 'parse';
 205
 206         /**
 207          * @var bool Whether database can be used.
 208          */
 209         protected $useDatabase = true;
 210
 211         /**
 212          * @var Title Title object to use as context.
 213          */
 214         protected $title = null;
 215
 216         /**
 217          * @var Content Content object representing the message.
 218          */
 219         protected $content = null;
 220
 221         /**
 222          * @var string
 223          */
 224         protected $message;
 225
 226         /**
 227          * @since 1.17
 228          *
 229          * @param string|string[] $key Message key or array of message keys to try and use the first
 230          * non-empty message for.
 231          * @param array $params Message parameters.
 232          * @param Language $language Optional language of the message, defaults to $wgLang.
 233          *
 234          * @throws InvalidArgumentException
 235          */
 236         public function __construct( $key, $params = array(), Language $language = null ) {
 237                 global $wgLang;
 238
 239                 if ( !is_string( $key ) && !is_array( $key ) ) {
 240                         throw new InvalidArgumentException( '$key must be a string or an array' );
 241                 }
 242
 243                 $this->keysToTry = (array)$key;
 244
 245                 if ( empty( $this->keysToTry ) ) {
 246                         throw new InvalidArgumentException( '$key must not be an empty list' );
 247                 }
 248
 249                 $this->key = reset( $this->keysToTry );
 250
 251                 $this->parameters = array_values( $params );
 252                 $this->language = $language ?: $wgLang;
 253         }
 254
 255         /**
 256          * @since 1.24
 257          *
 258          * @return bool True if this is a multi-key message, that is, if the key provided to the
 259          * constructor was a fallback list of keys to try.
 260          */
 261         public function isMultiKey() {
 262                 return count( $this->keysToTry ) > 1;
 263         }
 264
 265         /**
 266          * @since 1.24
 267          *
 268          * @return string[] The list of keys to try when fetching the message text,
 269          * in order of preference.
 270          */
 271         public function getKeysToTry() {
 272                 return $this->keysToTry;
 273         }
 274
 275         /**
 276          * Returns the message key.
 277          *
 278          * If a list of multiple possible keys was supplied to the constructor, this method may
 279          * return any of these keys. After the message has been fetched, this method will return
 280          * the key that was actually used to fetch the message.
 281          *
 282          * @since 1.21
 283          *
 284          * @return string
 285          */
 286         public function getKey() {
 287                 return $this->key;
 288         }
 289
 290         /**
 291          * Returns the message parameters.
 292          *
 293          * @since 1.21
 294          *
 295          * @return array
 296          */
 297         public function getParams() {
 298                 return $this->parameters;
 299         }
 300
 301         /**
 302          * Returns the message format.
 303          *
 304          * @since 1.21
 305          *
 306          * @return string
 307          */
 308         public function getFormat() {
 309                 return $this->format;
 310         }
 311
 312         /**
 313          * Returns the Language of the Message.
 314          *
 315          * @since 1.23
 316          *
 317          * @return Language
 318          */
 319         public function getLanguage() {
 320                 return $this->language;
 321         }
 322
 323         /**
 324          * Factory function that is just wrapper for the real constructor. It is
 325          * intended to be used instead of the real constructor, because it allows
 326          * chaining method calls, while new objects don't.
 327          *
 328          * @since 1.17
 329          *
 330          * @param string|string[] $key Message key or array of keys.
 331          * @param mixed $param,... Parameters as strings.
 332          *
 333          * @return Message
 334          */
 335         public static function newFromKey( $key /*...*/ ) {
 336                 $params = func_get_args();
 337                 array_shift( $params );
 338                 return new self( $key, $params );
 339         }
 340
 341         /**
 342          * Factory function accepting multiple message keys and returning a message instance
 343          * for the first message which is non-empty. If all messages are empty then an
 344          * instance of the first message key is returned.
 345          *
 346          * @since 1.18
 347          *
 348          * @param string|string[] $keys,... Message keys, or first argument as an array of all the
 349          * message keys.
 350          *
 351          * @return Message
 352          */
 353         public static function newFallbackSequence( /*...*/ ) {
 354                 $keys = func_get_args();
 355                 if ( func_num_args() == 1 ) {
 356                         if ( is_array( $keys[0] ) ) {
 357                                 // Allow an array to be passed as the first argument instead
 358                                 $keys = array_values( $keys[0] );
 359                         } else {
 360                                 // Optimize a single string to not need special fallback handling
 361                                 $keys = $keys[0];
 362                         }
 363                 }
 364                 return new self( $keys );
 365         }
 366
 367         /**
 368          * Adds parameters to the parameter list of this message.
 369          *
 370          * @since 1.17
 371          *
 372          * @param mixed $params,... Parameters as strings, or a single argument that is
 373          * an array of strings.
 374          *
 375          * @return Message $this
 376          */
 377         public function params( /*...*/ ) {
 378                 $args = func_get_args();
 379                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 380                         $args = $args[0];
 381                 }
 382                 $args_values = array_values( $args );
 383                 $this->parameters = array_merge( $this->parameters, $args_values );
 384                 return $this;
 385         }
 386
 387         /**
 388          * Add parameters that are substituted after parsing or escaping.
 389          * In other words the parsing process cannot access the contents
 390          * of this type of parameter, and you need to make sure it is
 391          * sanitized beforehand.  The parser will see "$n", instead.
 392          *
 393          * @since 1.17
 394          *
 395          * @param mixed $params,... Raw parameters as strings, or a single argument that is
 396          * an array of raw parameters.
 397          *
 398          * @return Message $this
 399          */
 400         public function rawParams( /*...*/ ) {
 401                 $params = func_get_args();
 402                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 403                         $params = $params[0];
 404                 }
 405                 foreach ( $params as $param ) {
 406                         $this->parameters[] = self::rawParam( $param );
 407                 }
 408                 return $this;
 409         }
 410
 411         /**
 412          * Add parameters that are numeric and will be passed through
 413          * Language::formatNum before substitution
 414          *
 415          * @since 1.18
 416          *
 417          * @param mixed $param,... Numeric parameters, or a single argument that is
 418          * an array of numeric parameters.
 419          *
 420          * @return Message $this
 421          */
 422         public function numParams( /*...*/ ) {
 423                 $params = func_get_args();
 424                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 425                         $params = $params[0];
 426                 }
 427                 foreach ( $params as $param ) {
 428                         $this->parameters[] = self::numParam( $param );
 429                 }
 430                 return $this;
 431         }
 432
 433         /**
 434          * Add parameters that are durations of time and will be passed through
 435          * Language::formatDuration before substitution
 436          *
 437          * @since 1.22
 438          *
 439          * @param int|int[] $param,... Duration parameters, or a single argument that is
 440          * an array of duration parameters.
 441          *
 442          * @return Message $this
 443          */
 444         public function durationParams( /*...*/ ) {
 445                 $params = func_get_args();
 446                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 447                         $params = $params[0];
 448                 }
 449                 foreach ( $params as $param ) {
 450                         $this->parameters[] = self::durationParam( $param );
 451                 }
 452                 return $this;
 453         }
 454
 455         /**
 456          * Add parameters that are expiration times and will be passed through
 457          * Language::formatExpiry before substitution
 458          *
 459          * @since 1.22
 460          *
 461          * @param string|string[] $param,... Expiry parameters, or a single argument that is
 462          * an array of expiry parameters.
 463          *
 464          * @return Message $this
 465          */
 466         public function expiryParams( /*...*/ ) {
 467                 $params = func_get_args();
 468                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 469                         $params = $params[0];
 470                 }
 471                 foreach ( $params as $param ) {
 472                         $this->parameters[] = self::expiryParam( $param );
 473                 }
 474                 return $this;
 475         }
 476
 477         /**
 478          * Add parameters that are time periods and will be passed through
 479          * Language::formatTimePeriod before substitution
 480          *
 481          * @since 1.22
 482          *
 483          * @param int|int[] $param,... Time period parameters, or a single argument that is
 484          * an array of time period parameters.
 485          *
 486          * @return Message $this
 487          */
 488         public function timeperiodParams( /*...*/ ) {
 489                 $params = func_get_args();
 490                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 491                         $params = $params[0];
 492                 }
 493                 foreach ( $params as $param ) {
 494                         $this->parameters[] = self::timeperiodParam( $param );
 495                 }
 496                 return $this;
 497         }
 498
 499         /**
 500          * Add parameters that are file sizes and will be passed through
 501          * Language::formatSize before substitution
 502          *
 503          * @since 1.22
 504          *
 505          * @param int|int[] $param,... Size parameters, or a single argument that is
 506          * an array of size parameters.
 507          *
 508          * @return Message $this
 509          */
 510         public function sizeParams( /*...*/ ) {
 511                 $params = func_get_args();
 512                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 513                         $params = $params[0];
 514                 }
 515                 foreach ( $params as $param ) {
 516                         $this->parameters[] = self::sizeParam( $param );
 517                 }
 518                 return $this;
 519         }
 520
 521         /**
 522          * Add parameters that are bitrates and will be passed through
 523          * Language::formatBitrate before substitution
 524          *
 525          * @since 1.22
 526          *
 527          * @param int|int[] $param,... Bit rate parameters, or a single argument that is
 528          * an array of bit rate parameters.
 529          *
 530          * @return Message $this
 531          */
 532         public function bitrateParams( /*...*/ ) {
 533                 $params = func_get_args();
 534                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 535                         $params = $params[0];
 536                 }
 537                 foreach ( $params as $param ) {
 538                         $this->parameters[] = self::bitrateParam( $param );
 539                 }
 540                 return $this;
 541         }
 542
 543         /**
 544          * Add parameters that are plaintext and will be passed through without
 545          * the content being evaluated.  Plaintext parameters are not valid as
 546          * arguments to parser functions. This differs from self::rawParams in
 547          * that the Message class handles escaping to match the output format.
 548          *
 549          * @since 1.25
 550          *
 551          * @param string|string[] $param,... plaintext parameters, or a single argument that is
 552          * an array of plaintext parameters.
 553          *
 554          * @return Message $this
 555          */
 556         public function plaintextParams( /*...*/ ) {
 557                 $params = func_get_args();
 558                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 559                         $params = $params[0];
 560                 }
 561                 foreach ( $params as $param ) {
 562                         $this->parameters[] = self::plaintextParam( $param );
 563                 }
 564                 return $this;
 565         }
 566
 567         /**
 568          * Set the language and the title from a context object
 569          *
 570          * @since 1.19
 571          *
 572          * @param IContextSource $context
 573          *
 574          * @return Message $this
 575          */
 576         public function setContext( IContextSource $context ) {
 577                 $this->inLanguage( $context->getLanguage() );
 578                 $this->title( $context->getTitle() );
 579                 $this->interface = true;
 580
 581                 return $this;
 582         }
 583
 584         /**
 585          * Request the message in any language that is supported.
 586          * As a side effect interface message status is unconditionally
 587          * turned off.
 588          *
 589          * @since 1.17
 590          *
 591          * @param Language|string $lang Language code or Language object.
 592          *
 593          * @return Message $this
 594          * @throws MWException
 595          */
 596         public function inLanguage( $lang ) {
 597                 if ( $lang instanceof Language || $lang instanceof StubUserLang ) {
 598                         $this->language = $lang;
 599                 } elseif ( is_string( $lang ) ) {
 600                         if ( $this->language->getCode() != $lang ) {
 601                                 $this->language = Language::factory( $lang );
 602                         }
 603                 } else {
 604                         $type = gettype( $lang );
 605                         throw new MWException( __METHOD__ . " must be "
 606                                 . "passed a String or Language object; $type given"
 607                         );
 608                 }
 609                 $this->message = null;
 610                 $this->interface = false;
 611                 return $this;
 612         }
 613
 614         /**
 615          * Request the message in the wiki's content language,
 616          * unless it is disabled for this message.
 617          *
 618          * @since 1.17
 619          * @see $wgForceUIMsgAsContentMsg
 620          *
 621          * @return Message $this
 622          */
 623         public function inContentLanguage() {
 624                 global $wgForceUIMsgAsContentMsg;
 625                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 626                         return $this;
 627                 }
 628
 629                 global $wgContLang;
 630                 $this->inLanguage( $wgContLang );
 631                 return $this;
 632         }
 633
 634         /**
 635          * Allows manipulating the interface message flag directly.
 636          * Can be used to restore the flag after setting a language.
 637          *
 638          * @since 1.20
 639          *
 640          * @param bool $interface
 641          *
 642          * @return Message $this
 643          */
 644         public function setInterfaceMessageFlag( $interface ) {
 645                 $this->interface = (bool)$interface;
 646                 return $this;
 647         }
 648
 649         /**
 650          * Enable or disable database use.
 651          *
 652          * @since 1.17
 653          *
 654          * @param bool $useDatabase
 655          *
 656          * @return Message $this
 657          */
 658         public function useDatabase( $useDatabase ) {
 659                 $this->useDatabase = (bool)$useDatabase;
 660                 return $this;
 661         }
 662
 663         /**
 664          * Set the Title object to use as context when transforming the message
 665          *
 666          * @since 1.18
 667          *
 668          * @param Title $title
 669          *
 670          * @return Message $this
 671          */
 672         public function title( $title ) {
 673                 $this->title = $title;
 674                 return $this;
 675         }
 676
 677         /**
 678          * Returns the message as a Content object.
 679          *
 680          * @return Content
 681          */
 682         public function content() {
 683                 if ( !$this->content ) {
 684                         $this->content = new MessageContent( $this );
 685                 }
 686
 687                 return $this->content;
 688         }
 689
 690         /**
 691          * Returns the message parsed from wikitext to HTML.
 692          *
 693          * @since 1.17
 694          *
 695          * @return string HTML
 696          */
 697         public function toString() {
 698                 $string = $this->fetchMessage();
 699
 700                 if ( $string === false ) {
 701                         if ( $this->format === 'plain' || $this->format === 'text' ) {
 702                                 return '<' . $this->key . '>';
 703                         }
 704                         return '&lt;' . htmlspecialchars( $this->key ) . '&gt;';
 705                 }
 706
 707                 # Replace $* with a list of parameters for &uselang=qqx.
 708                 if ( strpos( $string, '$*' ) !== false ) {
 709                         $paramlist = '';
 710                         if ( $this->parameters !== array() ) {
 711                                 $paramlist = ': $' . implode( ', $', range( 1, count( $this->parameters ) ) );
 712                         }
 713                         $string = str_replace( '$*', $paramlist, $string );
 714                 }
 715
 716                 # Replace parameters before text parsing
 717                 $string = $this->replaceParameters( $string, 'before' );
 718
 719                 # Maybe transform using the full parser
 720                 if ( $this->format === 'parse' ) {
 721                         $string = $this->parseText( $string );
 722                         $string = Parser::stripOuterParagraph( $string );
 723                 } elseif ( $this->format === 'block-parse' ) {
 724                         $string = $this->parseText( $string );
 725                 } elseif ( $this->format === 'text' ) {
 726                         $string = $this->transformText( $string );
 727                 } elseif ( $this->format === 'escaped' ) {
 728                         $string = $this->transformText( $string );
 729                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 730                 }
 731
 732                 # Raw parameter replacement
 733                 $string = $this->replaceParameters( $string, 'after' );
 734
 735                 return $string;
 736         }
 737
 738         /**
 739          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 740          *     $foo = Message::get( $key );
 741          *     $string = "<abbr>$foo</abbr>";
 742          *
 743          * @since 1.18
 744          *
 745          * @return string
 746          */
 747         public function __toString() {
 748                 // PHP doesn't allow __toString to throw exceptions and will
 749                 // trigger a fatal error if it does. So, catch any exceptions.
 750
 751                 try {
 752                         return $this->toString();
 753                 } catch ( Exception $ex ) {
 754                         try {
 755                                 trigger_error( "Exception caught in " . __METHOD__ . " (message " . $this->key . "): "
 756                                         . $ex, E_USER_WARNING );
 757                         } catch ( Exception $ex ) {
 758                                 // Doh! Cause a fatal error after all?
 759                         }
 760
 761                         if ( $this->format === 'plain' || $this->format === 'text' ) {
 762                                 return '<' . $this->key . '>';
 763                         }
 764                         return '&lt;' . htmlspecialchars( $this->key ) . '&gt;';
 765                 }
 766         }
 767
 768         /**
 769          * Fully parse the text from wikitext to HTML.
 770          *
 771          * @since 1.17
 772          *
 773          * @return string Parsed HTML.
 774          */
 775         public function parse() {
 776                 $this->format = 'parse';
 777                 return $this->toString();
 778         }
 779
 780         /**
 781          * Returns the message text. {{-transformation is done.
 782          *
 783          * @since 1.17
 784          *
 785          * @return string Unescaped message text.
 786          */
 787         public function text() {
 788                 $this->format = 'text';
 789                 return $this->toString();
 790         }
 791
 792         /**
 793          * Returns the message text as-is, only parameters are substituted.
 794          *
 795          * @since 1.17
 796          *
 797          * @return string Unescaped untransformed message text.
 798          */
 799         public function plain() {
 800                 $this->format = 'plain';
 801                 return $this->toString();
 802         }
 803
 804         /**
 805          * Returns the parsed message text which is always surrounded by a block element.
 806          *
 807          * @since 1.17
 808          *
 809          * @return string HTML
 810          */
 811         public function parseAsBlock() {
 812                 $this->format = 'block-parse';
 813                 return $this->toString();
 814         }
 815
 816         /**
 817          * Returns the message text. {{-transformation is done and the result
 818          * is escaped excluding any raw parameters.
 819          *
 820          * @since 1.17
 821          *
 822          * @return string Escaped message text.
 823          */
 824         public function escaped() {
 825                 $this->format = 'escaped';
 826                 return $this->toString();
 827         }
 828
 829         /**
 830          * Check whether a message key has been defined currently.
 831          *
 832          * @since 1.17
 833          *
 834          * @return bool
 835          */
 836         public function exists() {
 837                 return $this->fetchMessage() !== false;
 838         }
 839
 840         /**
 841          * Check whether a message does not exist, or is an empty string
 842          *
 843          * @since 1.18
 844          * @todo FIXME: Merge with isDisabled()?
 845          *
 846          * @return bool
 847          */
 848         public function isBlank() {
 849                 $message = $this->fetchMessage();
 850                 return $message === false || $message === '';
 851         }
 852
 853         /**
 854          * Check whether a message does not exist, is an empty string, or is "-".
 855          *
 856          * @since 1.18
 857          *
 858          * @return bool
 859          */
 860         public function isDisabled() {
 861                 $message = $this->fetchMessage();
 862                 return $message === false || $message === '' || $message === '-';
 863         }
 864
 865         /**
 866          * @since 1.17
 867          *
 868          * @param mixed $raw
 869          *
 870          * @return array Array with a single "raw" key.
 871          */
 872         public static function rawParam( $raw ) {
 873                 return array( 'raw' => $raw );
 874         }
 875
 876         /**
 877          * @since 1.18
 878          *
 879          * @param mixed $num
 880          *
 881          * @return array Array with a single "num" key.
 882          */
 883         public static function numParam( $num ) {
 884                 return array( 'num' => $num );
 885         }
 886
 887         /**
 888          * @since 1.22
 889          *
 890          * @param int $duration
 891          *
 892          * @return int[] Array with a single "duration" key.
 893          */
 894         public static function durationParam( $duration ) {
 895                 return array( 'duration' => $duration );
 896         }
 897
 898         /**
 899          * @since 1.22
 900          *
 901          * @param string $expiry
 902          *
 903          * @return string[] Array with a single "expiry" key.
 904          */
 905         public static function expiryParam( $expiry ) {
 906                 return array( 'expiry' => $expiry );
 907         }
 908
 909         /**
 910          * @since 1.22
 911          *
 912          * @param number $period
 913          *
 914          * @return number[] Array with a single "period" key.
 915          */
 916         public static function timeperiodParam( $period ) {
 917                 return array( 'period' => $period );
 918         }
 919
 920         /**
 921          * @since 1.22
 922          *
 923          * @param int $size
 924          *
 925          * @return int[] Array with a single "size" key.
 926          */
 927         public static function sizeParam( $size ) {
 928                 return array( 'size' => $size );
 929         }
 930
 931         /**
 932          * @since 1.22
 933          *
 934          * @param int $bitrate
 935          *
 936          * @return int[] Array with a single "bitrate" key.
 937          */
 938         public static function bitrateParam( $bitrate ) {
 939                 return array( 'bitrate' => $bitrate );
 940         }
 941
 942         /**
 943          * @since 1.25
 944          *
 945          * @param string $plaintext
 946          *
 947          * @return string[] Array with a single "plaintext" key.
 948          */
 949         public static function plaintextParam( $plaintext ) {
 950                 return array( 'plaintext' => $plaintext );
 951         }
 952
 953         /**
 954          * Substitutes any parameters into the message text.
 955          *
 956          * @since 1.17
 957          *
 958          * @param string $message The message text.
 959          * @param string $type Either "before" or "after".
 960          *
 961          * @return string
 962          */
 963         protected function replaceParameters( $message, $type = 'before' ) {
 964                 $replacementKeys = array();
 965                 foreach ( $this->parameters as $n => $param ) {
 966                         list( $paramType, $value ) = $this->extractParam( $param );
 967                         if ( $type === $paramType ) {
 968                                 $replacementKeys['$' . ( $n + 1 )] = $value;
 969                         }
 970                 }
 971                 $message = strtr( $message, $replacementKeys );
 972                 return $message;
 973         }
 974
 975         /**
 976          * Extracts the parameter type and preprocessed the value if needed.
 977          *
 978          * @since 1.18
 979          *
 980          * @param mixed $param Parameter as defined in this class.
 981          *
 982          * @return array Array with the parameter type (either "before" or "after") and the value.
 983          */
 984         protected function extractParam( $param ) {
 985                 if ( is_array( $param ) ) {
 986                         if ( isset( $param['raw'] ) ) {
 987                                 return array( 'after', $param['raw'] );
 988                         } elseif ( isset( $param['num'] ) ) {
 989                                 // Replace number params always in before step for now.
 990                                 // No support for combined raw and num params
 991                                 return array( 'before', $this->language->formatNum( $param['num'] ) );
 992                         } elseif ( isset( $param['duration'] ) ) {
 993                                 return array( 'before', $this->language->formatDuration( $param['duration'] ) );
 994                         } elseif ( isset( $param['expiry'] ) ) {
 995                                 return array( 'before', $this->language->formatExpiry( $param['expiry'] ) );
 996                         } elseif ( isset( $param['period'] ) ) {
 997                                 return array( 'before', $this->language->formatTimePeriod( $param['period'] ) );
 998                         } elseif ( isset( $param['size'] ) ) {
 999                                 return array( 'before', $this->language->formatSize( $param['size'] ) );
1000                         } elseif ( isset( $param['bitrate'] ) ) {
1001                                 return array( 'before', $this->language->formatBitrate( $param['bitrate'] ) );
1002                         } elseif ( isset( $param['plaintext'] ) ) {
1003                                 return array( 'after', $this->formatPlaintext( $param['plaintext'] ) );
1004                         } else {
1005                                 $warning = 'Invalid parameter for message "' . $this->getKey() . '": ' .
1006                                         htmlspecialchars( serialize( $param ) );
1007                                 trigger_error( $warning, E_USER_WARNING );
1008                                 $e = new Exception;
1009                                 wfDebugLog( 'Bug58676', $warning . "\n" . $e->getTraceAsString() );
1010
1011                                 return array( 'before', '[INVALID]' );
1012                         }
1013                 } elseif ( $param instanceof Message ) {
1014                         // Message objects should not be before parameters because
1015                         // then they'll get double escaped. If the message needs to be
1016                         // escaped, it'll happen right here when we call toString().
1017                         return array( 'after', $param->toString() );
1018                 } else {
1019                         return array( 'before', $param );
1020                 }
1021         }
1022
1023         /**
1024          * Wrapper for what ever method we use to parse wikitext.
1025          *
1026          * @since 1.17
1027          *
1028          * @param string $string Wikitext message contents.
1029          *
1030          * @return string Wikitext parsed into HTML.
1031          */
1032         protected function parseText( $string ) {
1033                 $out = MessageCache::singleton()->parse(
1034                         $string,
1035                         $this->title,
1036                         /*linestart*/true,
1037                         $this->interface,
1038                         $this->language
1039                 );
1040
1041                 return $out instanceof ParserOutput ? $out->getText() : $out;
1042         }
1043
1044         /**
1045          * Wrapper for what ever method we use to {{-transform wikitext.
1046          *
1047          * @since 1.17
1048          *
1049          * @param string $string Wikitext message contents.
1050          *
1051          * @return string Wikitext with {{-constructs replaced with their values.
1052          */
1053         protected function transformText( $string ) {
1054                 return MessageCache::singleton()->transform(
1055                         $string,
1056                         $this->interface,
1057                         $this->language,
1058                         $this->title
1059                 );
1060         }
1061
1062         /**
1063          * Wrapper for what ever method we use to get message contents.
1064          *
1065          * @since 1.17
1066          *
1067          * @return string
1068          * @throws MWException If message key array is empty.
1069          */
1070         protected function fetchMessage() {
1071                 if ( $this->message === null ) {
1072                         $cache = MessageCache::singleton();
1073
1074                         foreach ( $this->keysToTry as $key ) {
1075                                 $message = $cache->get( $key, $this->useDatabase, $this->language );
1076                                 if ( $message !== false && $message !== '' ) {
1077                                         break;
1078                                 }
1079                         }
1080
1081                         // NOTE: The constructor makes sure keysToTry isn't empty,
1082                         //       so we know that $key and $message are initialized.
1083                         $this->key = $key;
1084                         $this->message = $message;
1085                 }
1086                 return $this->message;
1087         }
1088
1089         /**
1090          * Formats a message parameter wrapped with 'plaintext'. Ensures that
1091          * the entire string is displayed unchanged when displayed in the output
1092          * format.
1093          *
1094          * @since 1.25
1095          *
1096          * @param string $plaintext String to ensure plaintext output of
1097          *
1098          * @return string Input plaintext encoded for output to $this->format
1099          */
1100         protected function formatPlaintext( $plaintext ) {
1101                 switch ( $this->format ) {
1102                 case 'text':
1103                 case 'plain':
1104                         return $plaintext;
1105
1106                 case 'parse':
1107                 case 'block-parse':
1108                 case 'escaped':
1109                 default:
1110                         return htmlspecialchars( $plaintext, ENT_QUOTES );
1111
1112                 }
1113         }
1114 }
1115
1116 /**
1117  * Variant of the Message class.
1118  *
1119  * Rather than treating the message key as a lookup
1120  * value (which is passed to the MessageCache and
1121  * translated as necessary), a RawMessage key is
1122  * treated as the actual message.
1123  *
1124  * All other functionality (parsing, escaping, etc.)
1125  * is preserved.
1126  *
1127  * @since 1.21
1128  */
1129 class RawMessage extends Message {
1130
1131         /**
1132          * Call the parent constructor, then store the key as
1133          * the message.
1134          *
1135          * @see Message::__construct
1136          *
1137          * @param string $text Message to use.
1138          * @param array $params Parameters for the message.
1139          *
1140          * @throws InvalidArgumentException
1141          */
1142         public function __construct( $text, $params = array() ) {
1143                 if ( !is_string( $text ) ) {
1144                         throw new InvalidArgumentException( '$text must be a string' );
1145                 }
1146
1147                 parent::__construct( $text, $params );
1148
1149                 // The key is the message.
1150                 $this->message = $text;
1151         }
1152
1153         /**
1154          * Fetch the message (in this case, the key).
1155          *
1156          * @return string
1157          */
1158         public function fetchMessage() {
1159                 // Just in case the message is unset somewhere.
1160                 if ( $this->message === null ) {
1161                         $this->message = $this->key;
1162                 }
1163
1164                 return $this->message;
1165         }
1166
1167 }