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                 $previousLanguage = $this->language;
 730
 731                 if ( $lang instanceof Language ) {
 732                         $this->language = $lang;
 733                 } elseif ( is_string( $lang ) ) {
 734                         if ( !$this->language instanceof Language || $this->language->getCode() != $lang ) {
 735                                 $this->language = Language::factory( $lang );
 736                         }
 737                 } elseif ( $lang instanceof StubUserLang ) {
 738                         $this->language = false;
 739                 } else {
 740                         $type = gettype( $lang );
 741                         throw new MWException( __METHOD__ . " must be "
 742                                 . "passed a String or Language object; $type given"
 743                         );
 744                 }
 745
 746                 if ( $this->language !== $previousLanguage ) {
 747                         // The language has changed. Clear the message cache.
 748                         $this->message = null;
 749                 }
 750                 $this->interface = false;
 751                 return $this;
 752         }
 753
 754         /**
 755          * Request the message in the wiki's content language,
 756          * unless it is disabled for this message.
 757          *
 758          * @since 1.17
 759          * @see $wgForceUIMsgAsContentMsg
 760          *
 761          * @return Message $this
 762          */
 763         public function inContentLanguage() {
 764                 global $wgForceUIMsgAsContentMsg;
 765                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 766                         return $this;
 767                 }
 768
 769                 global $wgContLang;
 770                 $this->inLanguage( $wgContLang );
 771                 return $this;
 772         }
 773
 774         /**
 775          * Allows manipulating the interface message flag directly.
 776          * Can be used to restore the flag after setting a language.
 777          *
 778          * @since 1.20
 779          *
 780          * @param bool $interface
 781          *
 782          * @return Message $this
 783          */
 784         public function setInterfaceMessageFlag( $interface ) {
 785                 $this->interface = (bool)$interface;
 786                 return $this;
 787         }
 788
 789         /**
 790          * Enable or disable database use.
 791          *
 792          * @since 1.17
 793          *
 794          * @param bool $useDatabase
 795          *
 796          * @return Message $this
 797          */
 798         public function useDatabase( $useDatabase ) {
 799                 $this->useDatabase = (bool)$useDatabase;
 800                 $this->message = null;
 801                 return $this;
 802         }
 803
 804         /**
 805          * Set the Title object to use as context when transforming the message
 806          *
 807          * @since 1.18
 808          *
 809          * @param Title $title
 810          *
 811          * @return Message $this
 812          */
 813         public function title( $title ) {
 814                 $this->title = $title;
 815                 return $this;
 816         }
 817
 818         /**
 819          * Returns the message as a Content object.
 820          *
 821          * @return Content
 822          */
 823         public function content() {
 824                 if ( !$this->content ) {
 825                         $this->content = new MessageContent( $this );
 826                 }
 827
 828                 return $this->content;
 829         }
 830
 831         /**
 832          * Returns the message parsed from wikitext to HTML.
 833          *
 834          * @since 1.17
 835          *
 836          * @param string|null $format One of the FORMAT_* constants. Null means use whatever was used
 837          *   the last time (this is for B/C and should be avoided).
 838          *
 839          * @return string HTML
 840          */
 841         public function toString( $format = null ) {
 842                 if ( $format === null ) {
 843                         $ex = new LogicException( __METHOD__ . ' using implicit format: ' . $this->format );
 844                         \MediaWiki\Logger\LoggerFactory::getInstance( 'message-format' )->warning(
 845                                 $ex->getMessage(), [ 'exception' => $ex, 'format' => $this->format, 'key' => $this->key ] );
 846                         $format = $this->format;
 847                 }
 848                 $string = $this->fetchMessage();
 849
 850                 if ( $string === false ) {
 851                         // Err on the side of safety, ensure that the output
 852                         // is always html safe in the event the message key is
 853                         // missing, since in that case its highly likely the
 854                         // message key is user-controlled.
 855                         // '⧼' is used instead of '<' to side-step any
 856                         // double-escaping issues.
 857                         // (Keep synchronised with mw.Message#toString in JS.)
 858                         return '⧼' . htmlspecialchars( $this->key ) . '⧽';
 859                 }
 860
 861                 # Replace $* with a list of parameters for &uselang=qqx.
 862                 if ( strpos( $string, '$*' ) !== false ) {
 863                         $paramlist = '';
 864                         if ( $this->parameters !== [] ) {
 865                                 $paramlist = ': $' . implode( ', $', range( 1, count( $this->parameters ) ) );
 866                         }
 867                         $string = str_replace( '$*', $paramlist, $string );
 868                 }
 869
 870                 # Replace parameters before text parsing
 871                 $string = $this->replaceParameters( $string, 'before', $format );
 872
 873                 # Maybe transform using the full parser
 874                 if ( $format === self::FORMAT_PARSE ) {
 875                         $string = $this->parseText( $string );
 876                         $string = Parser::stripOuterParagraph( $string );
 877                 } elseif ( $format === self::FORMAT_BLOCK_PARSE ) {
 878                         $string = $this->parseText( $string );
 879                 } elseif ( $format === self::FORMAT_TEXT ) {
 880                         $string = $this->transformText( $string );
 881                 } elseif ( $format === self::FORMAT_ESCAPED ) {
 882                         $string = $this->transformText( $string );
 883                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 884                 }
 885
 886                 # Raw parameter replacement
 887                 $string = $this->replaceParameters( $string, 'after', $format );
 888
 889                 return $string;
 890         }
 891
 892         /**
 893          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 894          *     $foo = new Message( $key );
 895          *     $string = "<abbr>$foo</abbr>";
 896          *
 897          * @since 1.18
 898          *
 899          * @return string
 900          */
 901         public function __toString() {
 902                 // PHP doesn't allow __toString to throw exceptions and will
 903                 // trigger a fatal error if it does. So, catch any exceptions.
 904
 905                 try {
 906                         return $this->toString( self::FORMAT_PARSE );
 907                 } catch ( Exception $ex ) {
 908                         try {
 909                                 trigger_error( "Exception caught in " . __METHOD__ . " (message " . $this->key . "): "
 910                                         . $ex, E_USER_WARNING );
 911                         } catch ( Exception $ex ) {
 912                                 // Doh! Cause a fatal error after all?
 913                         }
 914
 915                         return '⧼' . htmlspecialchars( $this->key ) . '⧽';
 916                 }
 917         }
 918
 919         /**
 920          * Fully parse the text from wikitext to HTML.
 921          *
 922          * @since 1.17
 923          *
 924          * @return string Parsed HTML.
 925          */
 926         public function parse() {
 927                 $this->format = self::FORMAT_PARSE;
 928                 return $this->toString( self::FORMAT_PARSE );
 929         }
 930
 931         /**
 932          * Returns the message text. {{-transformation is done.
 933          *
 934          * @since 1.17
 935          *
 936          * @return string Unescaped message text.
 937          */
 938         public function text() {
 939                 $this->format = self::FORMAT_TEXT;
 940                 return $this->toString( self::FORMAT_TEXT );
 941         }
 942
 943         /**
 944          * Returns the message text as-is, only parameters are substituted.
 945          *
 946          * @since 1.17
 947          *
 948          * @return string Unescaped untransformed message text.
 949          */
 950         public function plain() {
 951                 $this->format = self::FORMAT_PLAIN;
 952                 return $this->toString( self::FORMAT_PLAIN );
 953         }
 954
 955         /**
 956          * Returns the parsed message text which is always surrounded by a block element.
 957          *
 958          * @since 1.17
 959          *
 960          * @return string HTML
 961          */
 962         public function parseAsBlock() {
 963                 $this->format = self::FORMAT_BLOCK_PARSE;
 964                 return $this->toString( self::FORMAT_BLOCK_PARSE );
 965         }
 966
 967         /**
 968          * Returns the message text. {{-transformation is done and the result
 969          * is escaped excluding any raw parameters.
 970          *
 971          * @since 1.17
 972          *
 973          * @return string Escaped message text.
 974          */
 975         public function escaped() {
 976                 $this->format = self::FORMAT_ESCAPED;
 977                 return $this->toString( self::FORMAT_ESCAPED );
 978         }
 979
 980         /**
 981          * Check whether a message key has been defined currently.
 982          *
 983          * @since 1.17
 984          *
 985          * @return bool
 986          */
 987         public function exists() {
 988                 return $this->fetchMessage() !== false;
 989         }
 990
 991         /**
 992          * Check whether a message does not exist, or is an empty string
 993          *
 994          * @since 1.18
 995          * @todo FIXME: Merge with isDisabled()?
 996          *
 997          * @return bool
 998          */
 999         public function isBlank() {
1000                 $message = $this->fetchMessage();
1001                 return $message === false || $message === '';
1002         }
1003
1004         /**
1005          * Check whether a message does not exist, is an empty string, or is "-".
1006          *
1007          * @since 1.18
1008          *
1009          * @return bool
1010          */
1011         public function isDisabled() {
1012                 $message = $this->fetchMessage();
1013                 return $message === false || $message === '' || $message === '-';
1014         }
1015
1016         /**
1017          * @since 1.17
1018          *
1019          * @param mixed $raw
1020          *
1021          * @return array Array with a single "raw" key.
1022          */
1023         public static function rawParam( $raw ) {
1024                 return [ 'raw' => $raw ];
1025         }
1026
1027         /**
1028          * @since 1.18
1029          *
1030          * @param mixed $num
1031          *
1032          * @return array Array with a single "num" key.
1033          */
1034         public static function numParam( $num ) {
1035                 return [ 'num' => $num ];
1036         }
1037
1038         /**
1039          * @since 1.22
1040          *
1041          * @param int $duration
1042          *
1043          * @return int[] Array with a single "duration" key.
1044          */
1045         public static function durationParam( $duration ) {
1046                 return [ 'duration' => $duration ];
1047         }
1048
1049         /**
1050          * @since 1.22
1051          *
1052          * @param string $expiry
1053          *
1054          * @return string[] Array with a single "expiry" key.
1055          */
1056         public static function expiryParam( $expiry ) {
1057                 return [ 'expiry' => $expiry ];
1058         }
1059
1060         /**
1061          * @since 1.22
1062          *
1063          * @param int $period
1064          *
1065          * @return int[] Array with a single "period" key.
1066          */
1067         public static function timeperiodParam( $period ) {
1068                 return [ 'period' => $period ];
1069         }
1070
1071         /**
1072          * @since 1.22
1073          *
1074          * @param int $size
1075          *
1076          * @return int[] Array with a single "size" key.
1077          */
1078         public static function sizeParam( $size ) {
1079                 return [ 'size' => $size ];
1080         }
1081
1082         /**
1083          * @since 1.22
1084          *
1085          * @param int $bitrate
1086          *
1087          * @return int[] Array with a single "bitrate" key.
1088          */
1089         public static function bitrateParam( $bitrate ) {
1090                 return [ 'bitrate' => $bitrate ];
1091         }
1092
1093         /**
1094          * @since 1.25
1095          *
1096          * @param string $plaintext
1097          *
1098          * @return string[] Array with a single "plaintext" key.
1099          */
1100         public static function plaintextParam( $plaintext ) {
1101                 return [ 'plaintext' => $plaintext ];
1102         }
1103
1104         /**
1105          * @since 1.29
1106          *
1107          * @param array $list
1108          * @param string $type 'comma', 'semicolon', 'pipe', 'text'
1109          * @return array Array with "list" and "type" keys.
1110          */
1111         public static function listParam( array $list, $type = 'text' ) {
1112                 if ( !isset( self::$listTypeMap[$type] ) ) {
1113                         throw new InvalidArgumentException(
1114                                 "Invalid type '$type'. Known types are: " . implode( ', ', array_keys( self::$listTypeMap ) )
1115                         );
1116                 }
1117                 return [ 'list' => $list, 'type' => $type ];
1118         }
1119
1120         /**
1121          * Substitutes any parameters into the message text.
1122          *
1123          * @since 1.17
1124          *
1125          * @param string $message The message text.
1126          * @param string $type Either "before" or "after".
1127          * @param string $format One of the FORMAT_* constants.
1128          *
1129          * @return string
1130          */
1131         protected function replaceParameters( $message, $type, $format ) {
1132                 // A temporary marker for $1 parameters that is only valid
1133                 // in non-attribute contexts. However if the entire message is escaped
1134                 // then we don't want to use it because it will be mangled in all contexts
1135                 // and its unnessary as ->escaped() messages aren't html.
1136                 $marker = $format === self::FORMAT_ESCAPED ? '$' : '$\'"';
1137                 $replacementKeys = [];
1138                 foreach ( $this->parameters as $n => $param ) {
1139                         list( $paramType, $value ) = $this->extractParam( $param, $format );
1140                         if ( $type === 'before' ) {
1141                                 if ( $paramType === 'before' ) {
1142                                         $replacementKeys['$' . ( $n + 1 )] = $value;
1143                                 } else /* $paramType === 'after' */ {
1144                                         // To protect against XSS from replacing parameters
1145                                         // inside html attributes, we convert $1 to $'"1.
1146                                         // In the event that one of the parameters ends up
1147                                         // in an attribute, either the ' or the " will be
1148                                         // escaped, breaking the replacement and avoiding XSS.
1149                                         $replacementKeys['$' . ( $n + 1 )] = $marker . ( $n + 1 );
1150                                 }
1151                         } else {
1152                                 if ( $paramType === 'after' ) {
1153                                         $replacementKeys[$marker . ( $n + 1 )] = $value;
1154                                 }
1155                         }
1156                 }
1157                 $message = strtr( $message, $replacementKeys );
1158                 return $message;
1159         }
1160
1161         /**
1162          * Extracts the parameter type and preprocessed the value if needed.
1163          *
1164          * @since 1.18
1165          *
1166          * @param mixed $param Parameter as defined in this class.
1167          * @param string $format One of the FORMAT_* constants.
1168          *
1169          * @return array Array with the parameter type (either "before" or "after") and the value.
1170          */
1171         protected function extractParam( $param, $format ) {
1172                 if ( is_array( $param ) ) {
1173                         if ( isset( $param['raw'] ) ) {
1174                                 return [ 'after', $param['raw'] ];
1175                         } elseif ( isset( $param['num'] ) ) {
1176                                 // Replace number params always in before step for now.
1177                                 // No support for combined raw and num params
1178                                 return [ 'before', $this->getLanguage()->formatNum( $param['num'] ) ];
1179                         } elseif ( isset( $param['duration'] ) ) {
1180                                 return [ 'before', $this->getLanguage()->formatDuration( $param['duration'] ) ];
1181                         } elseif ( isset( $param['expiry'] ) ) {
1182                                 return [ 'before', $this->getLanguage()->formatExpiry( $param['expiry'] ) ];
1183                         } elseif ( isset( $param['period'] ) ) {
1184                                 return [ 'before', $this->getLanguage()->formatTimePeriod( $param['period'] ) ];
1185                         } elseif ( isset( $param['size'] ) ) {
1186                                 return [ 'before', $this->getLanguage()->formatSize( $param['size'] ) ];
1187                         } elseif ( isset( $param['bitrate'] ) ) {
1188                                 return [ 'before', $this->getLanguage()->formatBitrate( $param['bitrate'] ) ];
1189                         } elseif ( isset( $param['plaintext'] ) ) {
1190                                 return [ 'after', $this->formatPlaintext( $param['plaintext'], $format ) ];
1191                         } elseif ( isset( $param['list'] ) ) {
1192                                 return $this->formatListParam( $param['list'], $param['type'], $format );
1193                         } else {
1194                                 if ( !is_scalar( $param ) ) {
1195                                         $param = serialize( $param );
1196                                 }
1197                                 \MediaWiki\Logger\LoggerFactory::getInstance( 'Bug58676' )->warning(
1198                                         'Invalid parameter for message "{msgkey}": {param}',
1199                                         [
1200                                                 'exception' => new Exception,
1201                                                 'msgkey' => $this->getKey(),
1202                                                 'param' => htmlspecialchars( $param ),
1203                                         ]
1204                                 );
1205
1206                                 return [ 'before', '[INVALID]' ];
1207                         }
1208                 } elseif ( $param instanceof Message ) {
1209                         // Match language, flags, etc. to the current message.
1210                         $msg = clone $param;
1211                         if ( $msg->language !== $this->language || $msg->useDatabase !== $this->useDatabase ) {
1212                                 // Cache depends on these parameters
1213                                 $msg->message = null;
1214                         }
1215                         $msg->interface = $this->interface;
1216                         $msg->language = $this->language;
1217                         $msg->useDatabase = $this->useDatabase;
1218                         $msg->title = $this->title;
1219
1220                         // DWIM
1221                         if ( $format === 'block-parse' ) {
1222                                 $format = 'parse';
1223                         }
1224                         $msg->format = $format;
1225
1226                         // Message objects should not be before parameters because
1227                         // then they'll get double escaped. If the message needs to be
1228                         // escaped, it'll happen right here when we call toString().
1229                         return [ 'after', $msg->toString( $format ) ];
1230                 } else {
1231                         return [ 'before', $param ];
1232                 }
1233         }
1234
1235         /**
1236          * Wrapper for what ever method we use to parse wikitext.
1237          *
1238          * @since 1.17
1239          *
1240          * @param string $string Wikitext message contents.
1241          *
1242          * @return string Wikitext parsed into HTML.
1243          */
1244         protected function parseText( $string ) {
1245                 $out = MessageCache::singleton()->parse(
1246                         $string,
1247                         $this->title,
1248                         /*linestart*/true,
1249                         $this->interface,
1250                         $this->getLanguage()
1251                 );
1252
1253                 return $out instanceof ParserOutput
1254                         ? $out->getText( [
1255                                 'enableSectionEditLinks' => false,
1256                                 // Wrapping messages in an extra <div> is probably not expected. If
1257                                 // they're outside the content area they probably shouldn't be
1258                                 // targeted by CSS that's targeting the parser output, and if
1259                                 // they're inside they already are from the outer div.
1260                                 'unwrap' => true,
1261                         ] )
1262                         : $out;
1263         }
1264
1265         /**
1266          * Wrapper for what ever method we use to {{-transform wikitext.
1267          *
1268          * @since 1.17
1269          *
1270          * @param string $string Wikitext message contents.
1271          *
1272          * @return string Wikitext with {{-constructs replaced with their values.
1273          */
1274         protected function transformText( $string ) {
1275                 return MessageCache::singleton()->transform(
1276                         $string,
1277                         $this->interface,
1278                         $this->getLanguage(),
1279                         $this->title
1280                 );
1281         }
1282
1283         /**
1284          * Wrapper for what ever method we use to get message contents.
1285          *
1286          * @since 1.17
1287          *
1288          * @return string
1289          * @throws MWException If message key array is empty.
1290          */
1291         protected function fetchMessage() {
1292                 if ( $this->message === null ) {
1293                         $cache = MessageCache::singleton();
1294
1295                         foreach ( $this->keysToTry as $key ) {
1296                                 $message = $cache->get( $key, $this->useDatabase, $this->getLanguage() );
1297                                 if ( $message !== false && $message !== '' ) {
1298                                         break;
1299                                 }
1300                         }
1301
1302                         // NOTE: The constructor makes sure keysToTry isn't empty,
1303                         //       so we know that $key and $message are initialized.
1304                         $this->key = $key;
1305                         $this->message = $message;
1306                 }
1307                 return $this->message;
1308         }
1309
1310         /**
1311          * Formats a message parameter wrapped with 'plaintext'. Ensures that
1312          * the entire string is displayed unchanged when displayed in the output
1313          * format.
1314          *
1315          * @since 1.25
1316          *
1317          * @param string $plaintext String to ensure plaintext output of
1318          * @param string $format One of the FORMAT_* constants.
1319          *
1320          * @return string Input plaintext encoded for output to $format
1321          */
1322         protected function formatPlaintext( $plaintext, $format ) {
1323                 switch ( $format ) {
1324                         case self::FORMAT_TEXT:
1325                         case self::FORMAT_PLAIN:
1326                                 return $plaintext;
1327
1328                         case self::FORMAT_PARSE:
1329                         case self::FORMAT_BLOCK_PARSE:
1330                         case self::FORMAT_ESCAPED:
1331                         default:
1332                                 return htmlspecialchars( $plaintext, ENT_QUOTES );
1333                 }
1334         }
1335
1336         /**
1337          * Formats a list of parameters as a concatenated string.
1338          * @since 1.29
1339          * @param array $params
1340          * @param string $listType
1341          * @param string $format One of the FORMAT_* constants.
1342          * @return array Array with the parameter type (either "before" or "after") and the value.
1343          */
1344         protected function formatListParam( array $params, $listType, $format ) {
1345                 if ( !isset( self::$listTypeMap[$listType] ) ) {
1346                         $warning = 'Invalid list type for message "' . $this->getKey() . '": '
1347                                 . htmlspecialchars( $listType )
1348                                 . ' (params are ' . htmlspecialchars( serialize( $params ) ) . ')';
1349                         trigger_error( $warning, E_USER_WARNING );
1350                         $e = new Exception;
1351                         wfDebugLog( 'Bug58676', $warning . "\n" . $e->getTraceAsString() );
1352                         return [ 'before', '[INVALID]' ];
1353                 }
1354                 $func = self::$listTypeMap[$listType];
1355
1356                 // Handle an empty list sensibly
1357                 if ( !$params ) {
1358                         return [ 'before', $this->getLanguage()->$func( [] ) ];
1359                 }
1360
1361                 // First, determine what kinds of list items we have
1362                 $types = [];
1363                 $vars = [];
1364                 $list = [];
1365                 foreach ( $params as $n => $p ) {
1366                         list( $type, $value ) = $this->extractParam( $p, $format );
1367                         $types[$type] = true;
1368                         $list[] = $value;
1369                         $vars[] = '$' . ( $n + 1 );
1370                 }
1371
1372                 // Easy case: all are 'before' or 'after', so just join the
1373                 // values and use the same type.
1374                 if ( count( $types ) === 1 ) {
1375                         return [ key( $types ), $this->getLanguage()->$func( $list ) ];
1376                 }
1377
1378                 // Hard case: We need to process each value per its type, then
1379                 // return the concatenated values as 'after'. We handle this by turning
1380                 // the list into a RawMessage and processing that as a parameter.
1381                 $vars = $this->getLanguage()->$func( $vars );
1382                 return $this->extractParam( new RawMessage( $vars, $params ), $format );
1383         }
1384 }