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', [ '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', [ '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, Serializable {
 160         /** Use message text as-is */
 161         const FORMAT_PLAIN = 'plain';
 162         /** Use normal wikitext -> HTML parsing (the result will be wrapped in a block-level HTML tag) */
 163         const FORMAT_BLOCK_PARSE = 'block-parse';
 164         /** Use normal wikitext -> HTML parsing but strip the block-level wrapper */
 165         const FORMAT_PARSE = 'parse';
 166         /** Transform {{..}} constructs but don't transform to HTML */
 167         const FORMAT_TEXT = 'text';
 168         /** Transform {{..}} constructs, HTML-escape the result */
 169         const FORMAT_ESCAPED = 'escaped';
 170
 171         /**
 172          * Mapping from Message::listParam() types to Language methods.
 173          * @var array
 174          */
 175         protected static $listTypeMap = [
 176                 'comma' => 'commaList',
 177                 'semicolon' => 'semicolonList',
 178                 'pipe' => 'pipeList',
 179                 'text' => 'listToText',
 180         ];
 181
 182         /**
 183          * In which language to get this message. True, which is the default,
 184          * means the current user language, false content language.
 185          *
 186          * @var bool
 187          */
 188         protected $interface = true;
 189
 190         /**
 191          * In which language to get this message. Overrides the $interface setting.
 192          *
 193          * @var Language|bool Explicit language object, or false for user language
 194          */
 195         protected $language = false;
 196
 197         /**
 198          * @var string The message key. If $keysToTry has more than one element,
 199          * this may change to one of the keys to try when fetching the message text.
 200          */
 201         protected $key;
 202
 203         /**
 204          * @var string[] List of keys to try when fetching the message.
 205          */
 206         protected $keysToTry;
 207
 208         /**
 209          * @var array List of parameters which will be substituted into the message.
 210          */
 211         protected $parameters = [];
 212
 213         /**
 214          * @var string
 215          * @deprecated
 216          */
 217         protected $format = 'parse';
 218
 219         /**
 220          * @var bool Whether database can be used.
 221          */
 222         protected $useDatabase = true;
 223
 224         /**
 225          * @var Title Title object to use as context.
 226          */
 227         protected $title = null;
 228
 229         /**
 230          * @var Content Content object representing the message.
 231          */
 232         protected $content = null;
 233
 234         /**
 235          * @var string
 236          */
 237         protected $message;
 238
 239         /**
 240          * @since 1.17
 241          * @param string|string[]|MessageSpecifier $key Message key, or array of
 242          * message keys to try and use the first non-empty message for, or a
 243          * MessageSpecifier to copy from.
 244          * @param array $params Message parameters.
 245          * @param Language $language [optional] Language to use (defaults to current user language).
 246          * @throws InvalidArgumentException
 247          */
 248         public function __construct( $key, $params = [], Language $language = null ) {
 249                 if ( $key instanceof MessageSpecifier ) {
 250                         if ( $params ) {
 251                                 throw new InvalidArgumentException(
 252                                         '$params must be empty if $key is a MessageSpecifier'
 253                                 );
 254                         }
 255                         $params = $key->getParams();
 256                         $key = $key->getKey();
 257                 }
 258
 259                 if ( !is_string( $key ) && !is_array( $key ) ) {
 260                         throw new InvalidArgumentException( '$key must be a string or an array' );
 261                 }
 262
 263                 $this->keysToTry = (array)$key;
 264
 265                 if ( empty( $this->keysToTry ) ) {
 266                         throw new InvalidArgumentException( '$key must not be an empty list' );
 267                 }
 268
 269                 $this->key = reset( $this->keysToTry );
 270
 271                 $this->parameters = array_values( $params );
 272                 // User language is only resolved in getLanguage(). This helps preserve the
 273                 // semantic intent of "user language" across serialize() and unserialize().
 274                 $this->language = $language ?: false;
 275         }
 276
 277         /**
 278          * @see Serializable::serialize()
 279          * @since 1.26
 280          * @return string
 281          */
 282         public function serialize() {
 283                 return serialize( [
 284                         'interface' => $this->interface,
 285                         'language' => $this->language ? $this->language->getCode() : false,
 286                         'key' => $this->key,
 287                         'keysToTry' => $this->keysToTry,
 288                         'parameters' => $this->parameters,
 289                         'format' => $this->format,
 290                         'useDatabase' => $this->useDatabase,
 291                         'title' => $this->title,
 292                 ] );
 293         }
 294
 295         /**
 296          * @see Serializable::unserialize()
 297          * @since 1.26
 298          * @param string $serialized
 299          */
 300         public function unserialize( $serialized ) {
 301                 $data = unserialize( $serialized );
 302                 $this->interface = $data['interface'];
 303                 $this->key = $data['key'];
 304                 $this->keysToTry = $data['keysToTry'];
 305                 $this->parameters = $data['parameters'];
 306                 $this->format = $data['format'];
 307                 $this->useDatabase = $data['useDatabase'];
 308                 $this->language = $data['language'] ? Language::factory( $data['language'] ) : false;
 309                 $this->title = $data['title'];
 310         }
 311
 312         /**
 313          * @since 1.24
 314          *
 315          * @return bool True if this is a multi-key message, that is, if the key provided to the
 316          * constructor was a fallback list of keys to try.
 317          */
 318         public function isMultiKey() {
 319                 return count( $this->keysToTry ) > 1;
 320         }
 321
 322         /**
 323          * @since 1.24
 324          *
 325          * @return string[] The list of keys to try when fetching the message text,
 326          * in order of preference.
 327          */
 328         public function getKeysToTry() {
 329                 return $this->keysToTry;
 330         }
 331
 332         /**
 333          * Returns the message key.
 334          *
 335          * If a list of multiple possible keys was supplied to the constructor, this method may
 336          * return any of these keys. After the message has been fetched, this method will return
 337          * the key that was actually used to fetch the message.
 338          *
 339          * @since 1.21
 340          *
 341          * @return string
 342          */
 343         public function getKey() {
 344                 return $this->key;
 345         }
 346
 347         /**
 348          * Returns the message parameters.
 349          *
 350          * @since 1.21
 351          *
 352          * @return array
 353          */
 354         public function getParams() {
 355                 return $this->parameters;
 356         }
 357
 358         /**
 359          * Returns the message format.
 360          *
 361          * @since 1.21
 362          *
 363          * @return string
 364          * @deprecated since 1.29 formatting is not stateful
 365          */
 366         public function getFormat() {
 367                 wfDeprecated( __METHOD__, '1.29' );
 368                 return $this->format;
 369         }
 370
 371         /**
 372          * Returns the Language of the Message.
 373          *
 374          * @since 1.23
 375          *
 376          * @return Language
 377          */
 378         public function getLanguage() {
 379                 // Defaults to false which means current user language
 380                 return $this->language ?: RequestContext::getMain()->getLanguage();
 381         }
 382
 383         /**
 384          * Factory function that is just wrapper for the real constructor. It is
 385          * intended to be used instead of the real constructor, because it allows
 386          * chaining method calls, while new objects don't.
 387          *
 388          * @since 1.17
 389          *
 390          * @param string|string[]|MessageSpecifier $key
 391          * @param mixed $param,... Parameters as strings.
 392          *
 393          * @return Message
 394          */
 395         public static function newFromKey( $key /*...*/ ) {
 396                 $params = func_get_args();
 397                 array_shift( $params );
 398                 return new self( $key, $params );
 399         }
 400
 401         /**
 402          * Transform a MessageSpecifier or a primitive value used interchangeably with
 403          * specifiers (a message key string, or a key + params array) into a proper Message.
 404          *
 405          * Also accepts a MessageSpecifier inside an array: that's not considered a valid format
 406          * but is an easy error to make due to how StatusValue stores messages internally.
 407          * Further array elements are ignored in that case.
 408          *
 409          * @param string|array|MessageSpecifier $value
 410          * @return Message
 411          * @throws InvalidArgumentException
 412          * @since 1.27
 413          */
 414         public static function newFromSpecifier( $value ) {
 415                 $params = [];
 416                 if ( is_array( $value ) ) {
 417                         $params = $value;
 418                         $value = array_shift( $params );
 419                 }
 420
 421                 if ( $value instanceof Message ) { // Message, RawMessage, ApiMessage, etc
 422                         $message = clone $value;
 423                 } elseif ( $value instanceof MessageSpecifier ) {
 424                         $message = new Message( $value );
 425                 } elseif ( is_string( $value ) ) {
 426                         $message = new Message( $value, $params );
 427                 } else {
 428                         throw new InvalidArgumentException( __METHOD__ . ': invalid argument type '
 429                                 . gettype( $value ) );
 430                 }
 431
 432                 return $message;
 433         }
 434
 435         /**
 436          * Factory function accepting multiple message keys and returning a message instance
 437          * for the first message which is non-empty. If all messages are empty then an
 438          * instance of the first message key is returned.
 439          *
 440          * @since 1.18
 441          *
 442          * @param string|string[] $keys,... Message keys, or first argument as an array of all the
 443          * message keys.
 444          *
 445          * @return Message
 446          */
 447         public static function newFallbackSequence( /*...*/ ) {
 448                 $keys = func_get_args();
 449                 if ( func_num_args() == 1 ) {
 450                         if ( is_array( $keys[0] ) ) {
 451                                 // Allow an array to be passed as the first argument instead
 452                                 $keys = array_values( $keys[0] );
 453                         } else {
 454                                 // Optimize a single string to not need special fallback handling
 455                                 $keys = $keys[0];
 456                         }
 457                 }
 458                 return new self( $keys );
 459         }
 460
 461         /**
 462          * Get a title object for a mediawiki message, where it can be found in the mediawiki namespace.
 463          * The title will be for the current language, if the message key is in
 464          * $wgForceUIMsgAsContentMsg it will be append with the language code (except content
 465          * language), because Message::inContentLanguage will also return in user language.
 466          *
 467          * @see $wgForceUIMsgAsContentMsg
 468          * @return Title
 469          * @since 1.26
 470          */
 471         public function getTitle() {
 472                 global $wgContLang, $wgForceUIMsgAsContentMsg;
 473
 474                 $title = $this->key;
 475                 if (
 476                         !$this->language->equals( $wgContLang )
 477                         && in_array( $this->key, (array)$wgForceUIMsgAsContentMsg )
 478                 ) {
 479                         $code = $this->language->getCode();
 480                         $title .= '/' . $code;
 481                 }
 482
 483                 return Title::makeTitle( NS_MEDIAWIKI, $wgContLang->ucfirst( strtr( $title, ' ', '_' ) ) );
 484         }
 485
 486         /**
 487          * Adds parameters to the parameter list of this message.
 488          *
 489          * @since 1.17
 490          *
 491          * @param mixed $args,... Parameters as strings or arrays from
 492          *  Message::numParam() and the like, or a single array of parameters.
 493          *
 494          * @return Message $this
 495          */
 496         public function params( /*...*/ ) {
 497                 $args = func_get_args();
 498
 499                 // If $args has only one entry and it's an array, then it's either a
 500                 // non-varargs call or it happens to be a call with just a single
 501                 // "special" parameter. Since the "special" parameters don't have any
 502                 // numeric keys, we'll test that to differentiate the cases.
 503                 if ( count( $args ) === 1 && isset( $args[0] ) && is_array( $args[0] ) ) {
 504                         if ( $args[0] === [] ) {
 505                                 $args = [];
 506                         } else {
 507                                 foreach ( $args[0] as $key => $value ) {
 508                                         if ( is_int( $key ) ) {
 509                                                 $args = $args[0];
 510                                                 break;
 511                                         }
 512                                 }
 513                         }
 514                 }
 515
 516                 $this->parameters = array_merge( $this->parameters, array_values( $args ) );
 517                 return $this;
 518         }
 519
 520         /**
 521          * Add parameters that are substituted after parsing or escaping.
 522          * In other words the parsing process cannot access the contents
 523          * of this type of parameter, and you need to make sure it is
 524          * sanitized beforehand.  The parser will see "$n", instead.
 525          *
 526          * @since 1.17
 527          *
 528          * @param mixed $params,... Raw parameters as strings, or a single argument that is
 529          * an array of raw parameters.
 530          *
 531          * @return Message $this
 532          */
 533         public function rawParams( /*...*/ ) {
 534                 $params = func_get_args();
 535                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 536                         $params = $params[0];
 537                 }
 538                 foreach ( $params as $param ) {
 539                         $this->parameters[] = self::rawParam( $param );
 540                 }
 541                 return $this;
 542         }
 543
 544         /**
 545          * Add parameters that are numeric and will be passed through
 546          * Language::formatNum before substitution
 547          *
 548          * @since 1.18
 549          *
 550          * @param mixed $param,... Numeric parameters, or a single argument that is
 551          * an array of numeric parameters.
 552          *
 553          * @return Message $this
 554          */
 555         public function numParams( /*...*/ ) {
 556                 $params = func_get_args();
 557                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 558                         $params = $params[0];
 559                 }
 560                 foreach ( $params as $param ) {
 561                         $this->parameters[] = self::numParam( $param );
 562                 }
 563                 return $this;
 564         }
 565
 566         /**
 567          * Add parameters that are durations of time and will be passed through
 568          * Language::formatDuration before substitution
 569          *
 570          * @since 1.22
 571          *
 572          * @param int|int[] $param,... Duration parameters, or a single argument that is
 573          * an array of duration parameters.
 574          *
 575          * @return Message $this
 576          */
 577         public function durationParams( /*...*/ ) {
 578                 $params = func_get_args();
 579                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 580                         $params = $params[0];
 581                 }
 582                 foreach ( $params as $param ) {
 583                         $this->parameters[] = self::durationParam( $param );
 584                 }
 585                 return $this;
 586         }
 587
 588         /**
 589          * Add parameters that are expiration times and will be passed through
 590          * Language::formatExpiry before substitution
 591          *
 592          * @since 1.22
 593          *
 594          * @param string|string[] $param,... Expiry parameters, or a single argument that is
 595          * an array of expiry parameters.
 596          *
 597          * @return Message $this
 598          */
 599         public function expiryParams( /*...*/ ) {
 600                 $params = func_get_args();
 601                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 602                         $params = $params[0];
 603                 }
 604                 foreach ( $params as $param ) {
 605                         $this->parameters[] = self::expiryParam( $param );
 606                 }
 607                 return $this;
 608         }
 609
 610         /**
 611          * Add parameters that are time periods and will be passed through
 612          * Language::formatTimePeriod before substitution
 613          *
 614          * @since 1.22
 615          *
 616          * @param int|int[] $param,... Time period parameters, or a single argument that is
 617          * an array of time period parameters.
 618          *
 619          * @return Message $this
 620          */
 621         public function timeperiodParams( /*...*/ ) {
 622                 $params = func_get_args();
 623                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 624                         $params = $params[0];
 625                 }
 626                 foreach ( $params as $param ) {
 627                         $this->parameters[] = self::timeperiodParam( $param );
 628                 }
 629                 return $this;
 630         }
 631
 632         /**
 633          * Add parameters that are file sizes and will be passed through
 634          * Language::formatSize before substitution
 635          *
 636          * @since 1.22
 637          *
 638          * @param int|int[] $param,... Size parameters, or a single argument that is
 639          * an array of size parameters.
 640          *
 641          * @return Message $this
 642          */
 643         public function sizeParams( /*...*/ ) {
 644                 $params = func_get_args();
 645                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 646                         $params = $params[0];
 647                 }
 648                 foreach ( $params as $param ) {
 649                         $this->parameters[] = self::sizeParam( $param );
 650                 }
 651                 return $this;
 652         }
 653
 654         /**
 655          * Add parameters that are bitrates and will be passed through
 656          * Language::formatBitrate before substitution
 657          *
 658          * @since 1.22
 659          *
 660          * @param int|int[] $param,... Bit rate parameters, or a single argument that is
 661          * an array of bit rate parameters.
 662          *
 663          * @return Message $this
 664          */
 665         public function bitrateParams( /*...*/ ) {
 666                 $params = func_get_args();
 667                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 668                         $params = $params[0];
 669                 }
 670                 foreach ( $params as $param ) {
 671                         $this->parameters[] = self::bitrateParam( $param );
 672                 }
 673                 return $this;
 674         }
 675
 676         /**
 677          * Add parameters that are plaintext and will be passed through without
 678          * the content being evaluated.  Plaintext parameters are not valid as
 679          * arguments to parser functions. This differs from self::rawParams in
 680          * that the Message class handles escaping to match the output format.
 681          *
 682          * @since 1.25
 683          *
 684          * @param string|string[] $param,... plaintext parameters, or a single argument that is
 685          * an array of plaintext parameters.
 686          *
 687          * @return Message $this
 688          */
 689         public function plaintextParams( /*...*/ ) {
 690                 $params = func_get_args();
 691                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 692                         $params = $params[0];
 693                 }
 694                 foreach ( $params as $param ) {
 695                         $this->parameters[] = self::plaintextParam( $param );
 696                 }
 697                 return $this;
 698         }
 699
 700         /**
 701          * Set the language and the title from a context object
 702          *
 703          * @since 1.19
 704          *
 705          * @param IContextSource $context
 706          *
 707          * @return Message $this
 708          */
 709         public function setContext( IContextSource $context ) {
 710                 $this->inLanguage( $context->getLanguage() );
 711                 $this->title( $context->getTitle() );
 712                 $this->interface = true;
 713
 714                 return $this;
 715         }
 716
 717         /**
 718          * Request the message in any language that is supported.
 719          *
 720          * As a side effect interface message status is unconditionally
 721          * turned off.
 722          *
 723          * @since 1.17
 724          * @param Language|string $lang Language code or Language object.
 725          * @return Message $this
 726          * @throws MWException
 727          */
 728         public function inLanguage( $lang ) {
 729                 if ( $lang instanceof Language ) {
 730                         $this->language = $lang;
 731                 } elseif ( is_string( $lang ) ) {
 732                         if ( !$this->language instanceof Language || $this->language->getCode() != $lang ) {
 733                                 $this->language = Language::factory( $lang );
 734                         }
 735                 } else {
 736                         $type = gettype( $lang );
 737                         throw new MWException( __METHOD__ . " must be "
 738                                 . "passed a String or Language object; $type given"
 739                         );
 740                 }
 741                 $this->message = null;
 742                 $this->interface = false;
 743                 return $this;
 744         }
 745
 746         /**
 747          * Request the message in the wiki's content language,
 748          * unless it is disabled for this message.
 749          *
 750          * @since 1.17
 751          * @see $wgForceUIMsgAsContentMsg
 752          *
 753          * @return Message $this
 754          */
 755         public function inContentLanguage() {
 756                 global $wgForceUIMsgAsContentMsg;
 757                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 758                         return $this;
 759                 }
 760
 761                 global $wgContLang;
 762                 $this->inLanguage( $wgContLang );
 763                 return $this;
 764         }
 765
 766         /**
 767          * Allows manipulating the interface message flag directly.
 768          * Can be used to restore the flag after setting a language.
 769          *
 770          * @since 1.20
 771          *
 772          * @param bool $interface
 773          *
 774          * @return Message $this
 775          */
 776         public function setInterfaceMessageFlag( $interface ) {
 777                 $this->interface = (bool)$interface;
 778                 return $this;
 779         }
 780
 781         /**
 782          * Enable or disable database use.
 783          *
 784          * @since 1.17
 785          *
 786          * @param bool $useDatabase
 787          *
 788          * @return Message $this
 789          */
 790         public function useDatabase( $useDatabase ) {
 791                 $this->useDatabase = (bool)$useDatabase;
 792                 $this->message = null;
 793                 return $this;
 794         }
 795
 796         /**
 797          * Set the Title object to use as context when transforming the message
 798          *
 799          * @since 1.18
 800          *
 801          * @param Title $title
 802          *
 803          * @return Message $this
 804          */
 805         public function title( $title ) {
 806                 $this->title = $title;
 807                 return $this;
 808         }
 809
 810         /**
 811          * Returns the message as a Content object.
 812          *
 813          * @return Content
 814          */
 815         public function content() {
 816                 if ( !$this->content ) {
 817                         $this->content = new MessageContent( $this );
 818                 }
 819
 820                 return $this->content;
 821         }
 822
 823         /**
 824          * Returns the message parsed from wikitext to HTML.
 825          *
 826          * @since 1.17
 827          *
 828          * @param string|null $format One of the FORMAT_* constants. Null means use whatever was used
 829          *   the last time (this is for B/C and should be avoided).
 830          *
 831          * @return string HTML
 832          */
 833         public function toString( $format = null ) {
 834                 if ( $format === null ) {
 835                         $ex = new LogicException( __METHOD__ . ' using implicit format: ' . $this->format );
 836                         \MediaWiki\Logger\LoggerFactory::getInstance( 'message-format' )->warning(
 837                                 $ex->getMessage(), [ 'exception' => $ex, 'format' => $this->format, 'key' => $this->key ] );
 838                         $format = $this->format;
 839                 }
 840                 $string = $this->fetchMessage();
 841
 842                 if ( $string === false ) {
 843                         // Err on the side of safety, ensure that the output
 844                         // is always html safe in the event the message key is
 845                         // missing, since in that case its highly likely the
 846                         // message key is user-controlled.
 847                         // '⧼' is used instead of '<' to side-step any
 848                         // double-escaping issues.
 849                         // (Keep synchronised with mw.Message#toString in JS.)
 850                         return '⧼' . htmlspecialchars( $this->key ) . '⧽';
 851                 }
 852
 853                 # Replace $* with a list of parameters for &uselang=qqx.
 854                 if ( strpos( $string, '$*' ) !== false ) {
 855                         $paramlist = '';
 856                         if ( $this->parameters !== [] ) {
 857                                 $paramlist = ': $' . implode( ', $', range( 1, count( $this->parameters ) ) );
 858                         }
 859                         $string = str_replace( '$*', $paramlist, $string );
 860                 }
 861
 862                 # Replace parameters before text parsing
 863                 $string = $this->replaceParameters( $string, 'before', $format );
 864
 865                 # Maybe transform using the full parser
 866                 if ( $format === self::FORMAT_PARSE ) {
 867                         $string = $this->parseText( $string );
 868                         $string = Parser::stripOuterParagraph( $string );
 869                 } elseif ( $format === self::FORMAT_BLOCK_PARSE ) {
 870                         $string = $this->parseText( $string );
 871                 } elseif ( $format === self::FORMAT_TEXT ) {
 872                         $string = $this->transformText( $string );
 873                 } elseif ( $format === self::FORMAT_ESCAPED ) {
 874                         $string = $this->transformText( $string );
 875                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 876                 }
 877
 878                 # Raw parameter replacement
 879                 $string = $this->replaceParameters( $string, 'after', $format );
 880
 881                 return $string;
 882         }
 883
 884         /**
 885          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 886          *     $foo = new Message( $key );
 887          *     $string = "<abbr>$foo</abbr>";
 888          *
 889          * @since 1.18
 890          *
 891          * @return string
 892          */
 893         public function __toString() {
 894                 // PHP doesn't allow __toString to throw exceptions and will
 895                 // trigger a fatal error if it does. So, catch any exceptions.
 896
 897                 try {
 898                         return $this->toString( self::FORMAT_PARSE );
 899                 } catch ( Exception $ex ) {
 900                         try {
 901                                 trigger_error( "Exception caught in " . __METHOD__ . " (message " . $this->key . "): "
 902                                         . $ex, E_USER_WARNING );
 903                         } catch ( Exception $ex ) {
 904                                 // Doh! Cause a fatal error after all?
 905                         }
 906
 907                         return '⧼' . htmlspecialchars( $this->key ) . '⧽';
 908                 }
 909         }
 910
 911         /**
 912          * Fully parse the text from wikitext to HTML.
 913          *
 914          * @since 1.17
 915          *
 916          * @return string Parsed HTML.
 917          */
 918         public function parse() {
 919                 $this->format = self::FORMAT_PARSE;
 920                 return $this->toString( self::FORMAT_PARSE );
 921         }
 922
 923         /**
 924          * Returns the message text. {{-transformation is done.
 925          *
 926          * @since 1.17
 927          *
 928          * @return string Unescaped message text.
 929          */
 930         public function text() {
 931                 $this->format = self::FORMAT_TEXT;
 932                 return $this->toString( self::FORMAT_TEXT );
 933         }
 934
 935         /**
 936          * Returns the message text as-is, only parameters are substituted.
 937          *
 938          * @since 1.17
 939          *
 940          * @return string Unescaped untransformed message text.
 941          */
 942         public function plain() {
 943                 $this->format = self::FORMAT_PLAIN;
 944                 return $this->toString( self::FORMAT_PLAIN );
 945         }
 946
 947         /**
 948          * Returns the parsed message text which is always surrounded by a block element.
 949          *
 950          * @since 1.17
 951          *
 952          * @return string HTML
 953          */
 954         public function parseAsBlock() {
 955                 $this->format = self::FORMAT_BLOCK_PARSE;
 956                 return $this->toString( self::FORMAT_BLOCK_PARSE );
 957         }
 958
 959         /**
 960          * Returns the message text. {{-transformation is done and the result
 961          * is escaped excluding any raw parameters.
 962          *
 963          * @since 1.17
 964          *
 965          * @return string Escaped message text.
 966          */
 967         public function escaped() {
 968                 $this->format = self::FORMAT_ESCAPED;
 969                 return $this->toString( self::FORMAT_ESCAPED );
 970         }
 971
 972         /**
 973          * Check whether a message key has been defined currently.
 974          *
 975          * @since 1.17
 976          *
 977          * @return bool
 978          */
 979         public function exists() {
 980                 return $this->fetchMessage() !== false;
 981         }
 982
 983         /**
 984          * Check whether a message does not exist, or is an empty string
 985          *
 986          * @since 1.18
 987          * @todo FIXME: Merge with isDisabled()?
 988          *
 989          * @return bool
 990          */
 991         public function isBlank() {
 992                 $message = $this->fetchMessage();
 993                 return $message === false || $message === '';
 994         }
 995
 996         /**
 997          * Check whether a message does not exist, is an empty string, or is "-".
 998          *
 999          * @since 1.18
1000          *
1001          * @return bool
1002          */
1003         public function isDisabled() {
1004                 $message = $this->fetchMessage();
1005                 return $message === false || $message === '' || $message === '-';
1006         }
1007
1008         /**
1009          * @since 1.17
1010          *
1011          * @param mixed $raw
1012          *
1013          * @return array Array with a single "raw" key.
1014          */
1015         public static function rawParam( $raw ) {
1016                 return [ 'raw' => $raw ];
1017         }
1018
1019         /**
1020          * @since 1.18
1021          *
1022          * @param mixed $num
1023          *
1024          * @return array Array with a single "num" key.
1025          */
1026         public static function numParam( $num ) {
1027                 return [ 'num' => $num ];
1028         }
1029
1030         /**
1031          * @since 1.22
1032          *
1033          * @param int $duration
1034          *
1035          * @return int[] Array with a single "duration" key.
1036          */
1037         public static function durationParam( $duration ) {
1038                 return [ 'duration' => $duration ];
1039         }
1040
1041         /**
1042          * @since 1.22
1043          *
1044          * @param string $expiry
1045          *
1046          * @return string[] Array with a single "expiry" key.
1047          */
1048         public static function expiryParam( $expiry ) {
1049                 return [ 'expiry' => $expiry ];
1050         }
1051
1052         /**
1053          * @since 1.22
1054          *
1055          * @param int $period
1056          *
1057          * @return int[] Array with a single "period" key.
1058          */
1059         public static function timeperiodParam( $period ) {
1060                 return [ 'period' => $period ];
1061         }
1062
1063         /**
1064          * @since 1.22
1065          *
1066          * @param int $size
1067          *
1068          * @return int[] Array with a single "size" key.
1069          */
1070         public static function sizeParam( $size ) {
1071                 return [ 'size' => $size ];
1072         }
1073
1074         /**
1075          * @since 1.22
1076          *
1077          * @param int $bitrate
1078          *
1079          * @return int[] Array with a single "bitrate" key.
1080          */
1081         public static function bitrateParam( $bitrate ) {
1082                 return [ 'bitrate' => $bitrate ];
1083         }
1084
1085         /**
1086          * @since 1.25
1087          *
1088          * @param string $plaintext
1089          *
1090          * @return string[] Array with a single "plaintext" key.
1091          */
1092         public static function plaintextParam( $plaintext ) {
1093                 return [ 'plaintext' => $plaintext ];
1094         }
1095
1096         /**
1097          * @since 1.29
1098          *
1099          * @param array $list
1100          * @param string $type 'comma', 'semicolon', 'pipe', 'text'
1101          * @return array Array with "list" and "type" keys.
1102          */
1103         public static function listParam( array $list, $type = 'text' ) {
1104                 if ( !isset( self::$listTypeMap[$type] ) ) {
1105                         throw new InvalidArgumentException(
1106                                 "Invalid type '$type'. Known types are: " . join( ', ', array_keys( self::$listTypeMap ) )
1107                         );
1108                 }
1109                 return [ 'list' => $list, 'type' => $type ];
1110         }
1111
1112         /**
1113          * Substitutes any parameters into the message text.
1114          *
1115          * @since 1.17
1116          *
1117          * @param string $message The message text.
1118          * @param string $type Either "before" or "after".
1119          * @param string $format One of the FORMAT_* constants.
1120          *
1121          * @return string
1122          */
1123         protected function replaceParameters( $message, $type = 'before', $format ) {
1124                 $replacementKeys = [];
1125                 foreach ( $this->parameters as $n => $param ) {
1126                         list( $paramType, $value ) = $this->extractParam( $param, $format );
1127                         if ( $type === $paramType ) {
1128                                 $replacementKeys['$' . ( $n + 1 )] = $value;
1129                         }
1130                 }
1131                 $message = strtr( $message, $replacementKeys );
1132                 return $message;
1133         }
1134
1135         /**
1136          * Extracts the parameter type and preprocessed the value if needed.
1137          *
1138          * @since 1.18
1139          *
1140          * @param mixed $param Parameter as defined in this class.
1141          * @param string $format One of the FORMAT_* constants.
1142          *
1143          * @return array Array with the parameter type (either "before" or "after") and the value.
1144          */
1145         protected function extractParam( $param, $format ) {
1146                 if ( is_array( $param ) ) {
1147                         if ( isset( $param['raw'] ) ) {
1148                                 return [ 'after', $param['raw'] ];
1149                         } elseif ( isset( $param['num'] ) ) {
1150                                 // Replace number params always in before step for now.
1151                                 // No support for combined raw and num params
1152                                 return [ 'before', $this->getLanguage()->formatNum( $param['num'] ) ];
1153                         } elseif ( isset( $param['duration'] ) ) {
1154                                 return [ 'before', $this->getLanguage()->formatDuration( $param['duration'] ) ];
1155                         } elseif ( isset( $param['expiry'] ) ) {
1156                                 return [ 'before', $this->getLanguage()->formatExpiry( $param['expiry'] ) ];
1157                         } elseif ( isset( $param['period'] ) ) {
1158                                 return [ 'before', $this->getLanguage()->formatTimePeriod( $param['period'] ) ];
1159                         } elseif ( isset( $param['size'] ) ) {
1160                                 return [ 'before', $this->getLanguage()->formatSize( $param['size'] ) ];
1161                         } elseif ( isset( $param['bitrate'] ) ) {
1162                                 return [ 'before', $this->getLanguage()->formatBitrate( $param['bitrate'] ) ];
1163                         } elseif ( isset( $param['plaintext'] ) ) {
1164                                 return [ 'after', $this->formatPlaintext( $param['plaintext'], $format ) ];
1165                         } elseif ( isset( $param['list'] ) ) {
1166                                 return $this->formatListParam( $param['list'], $param['type'], $format );
1167                         } else {
1168                                 $warning = 'Invalid parameter for message "' . $this->getKey() . '": ' .
1169                                         htmlspecialchars( serialize( $param ) );
1170                                 trigger_error( $warning, E_USER_WARNING );
1171                                 $e = new Exception;
1172                                 wfDebugLog( 'Bug58676', $warning . "\n" . $e->getTraceAsString() );
1173
1174                                 return [ 'before', '[INVALID]' ];
1175                         }
1176                 } elseif ( $param instanceof Message ) {
1177                         // Match language, flags, etc. to the current message.
1178                         $msg = clone $param;
1179                         if ( $msg->language !== $this->language || $msg->useDatabase !== $this->useDatabase ) {
1180                                 // Cache depends on these parameters
1181                                 $msg->message = null;
1182                         }
1183                         $msg->interface = $this->interface;
1184                         $msg->language = $this->language;
1185                         $msg->useDatabase = $this->useDatabase;
1186                         $msg->title = $this->title;
1187
1188                         // DWIM
1189                         if ( $format === 'block-parse' ) {
1190                                 $format = 'parse';
1191                         }
1192                         $msg->format = $format;
1193
1194                         // Message objects should not be before parameters because
1195                         // then they'll get double escaped. If the message needs to be
1196                         // escaped, it'll happen right here when we call toString().
1197                         return [ 'after', $msg->toString( $format ) ];
1198                 } else {
1199                         return [ 'before', $param ];
1200                 }
1201         }
1202
1203         /**
1204          * Wrapper for what ever method we use to parse wikitext.
1205          *
1206          * @since 1.17
1207          *
1208          * @param string $string Wikitext message contents.
1209          *
1210          * @return string Wikitext parsed into HTML.
1211          */
1212         protected function parseText( $string ) {
1213                 $out = MessageCache::singleton()->parse(
1214                         $string,
1215                         $this->title,
1216                         /*linestart*/true,
1217                         $this->interface,
1218                         $this->getLanguage()
1219                 );
1220
1221                 return $out instanceof ParserOutput ? $out->getText() : $out;
1222         }
1223
1224         /**
1225          * Wrapper for what ever method we use to {{-transform wikitext.
1226          *
1227          * @since 1.17
1228          *
1229          * @param string $string Wikitext message contents.
1230          *
1231          * @return string Wikitext with {{-constructs replaced with their values.
1232          */
1233         protected function transformText( $string ) {
1234                 return MessageCache::singleton()->transform(
1235                         $string,
1236                         $this->interface,
1237                         $this->getLanguage(),
1238                         $this->title
1239                 );
1240         }
1241
1242         /**
1243          * Wrapper for what ever method we use to get message contents.
1244          *
1245          * @since 1.17
1246          *
1247          * @return string
1248          * @throws MWException If message key array is empty.
1249          */
1250         protected function fetchMessage() {
1251                 if ( $this->message === null ) {
1252                         $cache = MessageCache::singleton();
1253
1254                         foreach ( $this->keysToTry as $key ) {
1255                                 $message = $cache->get( $key, $this->useDatabase, $this->getLanguage() );
1256                                 if ( $message !== false && $message !== '' ) {
1257                                         break;
1258                                 }
1259                         }
1260
1261                         // NOTE: The constructor makes sure keysToTry isn't empty,
1262                         //       so we know that $key and $message are initialized.
1263                         $this->key = $key;
1264                         $this->message = $message;
1265                 }
1266                 return $this->message;
1267         }
1268
1269         /**
1270          * Formats a message parameter wrapped with 'plaintext'. Ensures that
1271          * the entire string is displayed unchanged when displayed in the output
1272          * format.
1273          *
1274          * @since 1.25
1275          *
1276          * @param string $plaintext String to ensure plaintext output of
1277          * @param string $format One of the FORMAT_* constants.
1278          *
1279          * @return string Input plaintext encoded for output to $format
1280          */
1281         protected function formatPlaintext( $plaintext, $format ) {
1282                 switch ( $format ) {
1283                 case self::FORMAT_TEXT:
1284                 case self::FORMAT_PLAIN:
1285                         return $plaintext;
1286
1287                 case self::FORMAT_PARSE:
1288                 case self::FORMAT_BLOCK_PARSE:
1289                 case self::FORMAT_ESCAPED:
1290                 default:
1291                         return htmlspecialchars( $plaintext, ENT_QUOTES );
1292
1293                 }
1294         }
1295
1296         /**
1297          * Formats a list of parameters as a concatenated string.
1298          * @since 1.29
1299          * @param array $params
1300          * @param string $listType
1301          * @param string $format One of the FORMAT_* constants.
1302          * @return array Array with the parameter type (either "before" or "after") and the value.
1303          */
1304         protected function formatListParam( array $params, $listType, $format ) {
1305                 if ( !isset( self::$listTypeMap[$listType] ) ) {
1306                         $warning = 'Invalid list type for message "' . $this->getKey() . '": '
1307                                 . htmlspecialchars( $listType )
1308                                 . ' (params are ' . htmlspecialchars( serialize( $params ) ) . ')';
1309                         trigger_error( $warning, E_USER_WARNING );
1310                         $e = new Exception;
1311                         wfDebugLog( 'Bug58676', $warning . "\n" . $e->getTraceAsString() );
1312                         return [ 'before', '[INVALID]' ];
1313                 }
1314                 $func = self::$listTypeMap[$listType];
1315
1316                 // Handle an empty list sensibly
1317                 if ( !$params ) {
1318                         return [ 'before', $this->getLanguage()->$func( [] ) ];
1319                 }
1320
1321                 // First, determine what kinds of list items we have
1322                 $types = [];
1323                 $vars = [];
1324                 $list = [];
1325                 foreach ( $params as $n => $p ) {
1326                         list( $type, $value ) = $this->extractParam( $p, $format );
1327                         $types[$type] = true;
1328                         $list[] = $value;
1329                         $vars[] = '$' . ( $n + 1 );
1330                 }
1331
1332                 // Easy case: all are 'before' or 'after', so just join the
1333                 // values and use the same type.
1334                 if ( count( $types ) === 1 ) {
1335                         return [ key( $types ), $this->getLanguage()->$func( $list ) ];
1336                 }
1337
1338                 // Hard case: We need to process each value per its type, then
1339                 // return the concatenated values as 'after'. We handle this by turning
1340                 // the list into a RawMessage and processing that as a parameter.
1341                 $vars = $this->getLanguage()->$func( $vars );
1342                 return $this->extractParam( new RawMessage( $vars, $params ), $format );
1343         }
1344 }