includes/Message.php

   1 <?php
   2 /**
   3  * Fetching and processing of interface messages.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Niklas Laxström
  22  */
  23
  24 /**
  25  * The Message class provides methods which fulfil two basic services:
  26  *  - fetching interface messages
  27  *  - processing messages into a variety of formats
  28  *
  29  * First implemented with MediaWiki 1.17, the Message class is intended to
  30  * replace the old wfMsg* functions that over time grew unusable.
  31  * @see https://www.mediawiki.org/wiki/Manual:Messages_API for equivalences
  32  * between old and new functions.
  33  *
  34  * You should use the wfMessage() global function which acts as a wrapper for
  35  * the Message class. The wrapper let you pass parameters as arguments.
  36  *
  37  * The most basic usage cases would be:
  38  *
  39  * @code
  40  *     // Initialize a Message object using the 'some_key' message key
  41  *     $message = wfMessage( 'some_key' );
  42  *
  43  *     // Using two parameters those values are strings 'value1' and 'value2':
  44  *     $message = wfMessage( 'some_key',
  45  *          'value1', 'value2'
  46  *     );
  47  * @endcode
  48  *
  49  * @section message_global_fn Global function wrapper:
  50  *
  51  * Since wfMessage() returns a Message instance, you can chain its call with
  52  * a method. Some of them return a Message instance too so you can chain them.
  53  * You will find below several examples of wfMessage() usage.
  54  *
  55  * Fetching a message text for interface message:
  56  *
  57  * @code
  58  *    $button = Xml::button(
  59  *         wfMessage( 'submit' )->text()
  60  *    );
  61  * @endcode
  62  *
  63  * A Message instance can be passed parameters after it has been constructed,
  64  * use the params() method to do so:
  65  *
  66  * @code
  67  *     wfMessage( 'welcome-to' )
  68  *         ->params( $wgSitename )
  69  *         ->text();
  70  * @endcode
  71  *
  72  * {{GRAMMAR}} and friends work correctly:
  73  *
  74  * @code
  75  *    wfMessage( 'are-friends',
  76  *        $user, $friend
  77  *    );
  78  *    wfMessage( 'bad-message' )
  79  *         ->rawParams( '<script>...</script>' )
  80  *         ->escaped();
  81  * @endcode
  82  *
  83  * @section message_language Changing language:
  84  *
  85  * Messages can be requested in a different language or in whatever current
  86  * content language is being used. The methods are:
  87  *     - Message->inContentLanguage()
  88  *     - Message->inLanguage()
  89  *
  90  * Sometimes the message text ends up in the database, so content language is
  91  * needed:
  92  *
  93  * @code
  94  *    wfMessage( 'file-log',
  95  *        $user, $filename
  96  *    )->inContentLanguage()->text();
  97  * @endcode
  98  *
  99  * Checking whether a message exists:
 100  *
 101  * @code
 102  *    wfMessage( 'mysterious-message' )->exists()
 103  *    // returns a boolean whether the 'mysterious-message' key exist.
 104  * @endcode
 105  *
 106  * If you want to use a different language:
 107  *
 108  * @code
 109  *    $userLanguage = $user->getOption( 'language' );
 110  *    wfMessage( 'email-header' )
 111  *         ->inLanguage( $userLanguage )
 112  *         ->plain();
 113  * @endcode
 114  *
 115  * @note You can parse the text only in the content or interface languages
 116  *
 117  * @section message_compare_old Comparison with old wfMsg* functions:
 118  *
 119  * Use full parsing:
 120  *
 121  * @code
 122  *     // old style:
 123  *     wfMsgExt( 'key', array( 'parseinline' ), 'apple' );
 124  *     // new style:
 125  *     wfMessage( 'key', 'apple' )->parse();
 126  * @endcode
 127  *
 128  * Parseinline is used because it is more useful when pre-building HTML.
 129  * In normal use it is better to use OutputPage::(add|wrap)WikiMsg.
 130  *
 131  * Places where HTML cannot be used. {{-transformation is done.
 132  * @code
 133  *     // old style:
 134  *     wfMsgExt( 'key', array( 'parsemag' ), 'apple', 'pear' );
 135  *     // new style:
 136  *     wfMessage( 'key', 'apple', 'pear' )->text();
 137  * @endcode
 138  *
 139  * Shortcut for escaping the message too, similar to wfMsgHTML(), but
 140  * parameters are not replaced after escaping by default.
 141  * @code
 142  *     $escaped = wfMessage( 'key' )
 143  *          ->rawParams( 'apple' )
 144  *          ->escaped();
 145  * @endcode
 146  *
 147  * @section message_appendix Appendix:
 148  *
 149  * @todo
 150  * - test, can we have tests?
 151  * - this documentation needs to be extended
 152  *
 153  * @see https://www.mediawiki.org/wiki/WfMessage()
 154  * @see https://www.mediawiki.org/wiki/New_messages_API
 155  * @see https://www.mediawiki.org/wiki/Localisation
 156  *
 157  * @since 1.17
 158  */
 159 class Message implements MessageSpecifier, Serializable {
 160
 161         /**
 162          * In which language to get this message. True, which is the default,
 163          * means the current user language, false content language.
 164          *
 165          * @var bool
 166          */
 167         protected $interface = true;
 168
 169         /**
 170          * In which language to get this message. Overrides the $interface setting.
 171          *
 172          * @var Language|bool Explicit language object, or false for user language
 173          */
 174         protected $language = false;
 175
 176         /**
 177          * @var string The message key. If $keysToTry has more than one element,
 178          * this may change to one of the keys to try when fetching the message text.
 179          */
 180         protected $key;
 181
 182         /**
 183          * @var string[] List of keys to try when fetching the message.
 184          */
 185         protected $keysToTry;
 186
 187         /**
 188          * @var array List of parameters which will be substituted into the message.
 189          */
 190         protected $parameters = [];
 191
 192         /**
 193          * Format for the message.
 194          * Supported formats are:
 195          * * text (transform)
 196          * * escaped (transform+htmlspecialchars)
 197          * * block-parse
 198          * * parse (default)
 199          * * plain
 200          *
 201          * @var string
 202          */
 203         protected $format = 'parse';
 204
 205         /**
 206          * @var bool Whether database can be used.
 207          */
 208         protected $useDatabase = true;
 209
 210         /**
 211          * @var Title Title object to use as context.
 212          */
 213         protected $title = null;
 214
 215         /**
 216          * @var Content Content object representing the message.
 217          */
 218         protected $content = null;
 219
 220         /**
 221          * @var string
 222          */
 223         protected $message;
 224
 225         /**
 226          * @since 1.17
 227          * @param string|string[]|MessageSpecifier $key Message key, or array of
 228          * message keys to try and use the first non-empty message for, or a
 229          * MessageSpecifier to copy from.
 230          * @param array $params Message parameters.
 231          * @param Language $language [optional] Language to use (defaults to current user language).
 232          * @throws InvalidArgumentException
 233          */
 234         public function __construct( $key, $params = [], Language $language = null ) {
 235                 if ( $key instanceof MessageSpecifier ) {
 236                         if ( $params ) {
 237                                 throw new InvalidArgumentException(
 238                                         '$params must be empty if $key is a MessageSpecifier'
 239                                 );
 240                         }
 241                         $params = $key->getParams();
 242                         $key = $key->getKey();
 243                 }
 244
 245                 if ( !is_string( $key ) && !is_array( $key ) ) {
 246                         throw new InvalidArgumentException( '$key must be a string or an array' );
 247                 }
 248
 249                 $this->keysToTry = (array)$key;
 250
 251                 if ( empty( $this->keysToTry ) ) {
 252                         throw new InvalidArgumentException( '$key must not be an empty list' );
 253                 }
 254
 255                 $this->key = reset( $this->keysToTry );
 256
 257                 $this->parameters = array_values( $params );
 258                 // User language is only resolved in getLanguage(). This helps preserve the
 259                 // semantic intent of "user language" across serialize() and unserialize().
 260                 $this->language = $language ?: false;
 261         }
 262
 263         /**
 264          * @see Serializable::serialize()
 265          * @since 1.26
 266          * @return string
 267          */
 268         public function serialize() {
 269                 return serialize( [
 270                         'interface' => $this->interface,
 271                         'language' => $this->language ? $this->language->getCode() : false,
 272                         'key' => $this->key,
 273                         'keysToTry' => $this->keysToTry,
 274                         'parameters' => $this->parameters,
 275                         'format' => $this->format,
 276                         'useDatabase' => $this->useDatabase,
 277                         'title' => $this->title,
 278                 ] );
 279         }
 280
 281         /**
 282          * @see Serializable::unserialize()
 283          * @since 1.26
 284          * @param string $serialized
 285          */
 286         public function unserialize( $serialized ) {
 287                 $data = unserialize( $serialized );
 288                 $this->interface = $data['interface'];
 289                 $this->key = $data['key'];
 290                 $this->keysToTry = $data['keysToTry'];
 291                 $this->parameters = $data['parameters'];
 292                 $this->format = $data['format'];
 293                 $this->useDatabase = $data['useDatabase'];
 294                 $this->language = $data['language'] ? Language::factory( $data['language'] ) : false;
 295                 $this->title = $data['title'];
 296         }
 297
 298         /**
 299          * @since 1.24
 300          *
 301          * @return bool True if this is a multi-key message, that is, if the key provided to the
 302          * constructor was a fallback list of keys to try.
 303          */
 304         public function isMultiKey() {
 305                 return count( $this->keysToTry ) > 1;
 306         }
 307
 308         /**
 309          * @since 1.24
 310          *
 311          * @return string[] The list of keys to try when fetching the message text,
 312          * in order of preference.
 313          */
 314         public function getKeysToTry() {
 315                 return $this->keysToTry;
 316         }
 317
 318         /**
 319          * Returns the message key.
 320          *
 321          * If a list of multiple possible keys was supplied to the constructor, this method may
 322          * return any of these keys. After the message has been fetched, this method will return
 323          * the key that was actually used to fetch the message.
 324          *
 325          * @since 1.21
 326          *
 327          * @return string
 328          */
 329         public function getKey() {
 330                 return $this->key;
 331         }
 332
 333         /**
 334          * Returns the message parameters.
 335          *
 336          * @since 1.21
 337          *
 338          * @return array
 339          */
 340         public function getParams() {
 341                 return $this->parameters;
 342         }
 343
 344         /**
 345          * Returns the message format.
 346          *
 347          * @since 1.21
 348          *
 349          * @return string
 350          */
 351         public function getFormat() {
 352                 return $this->format;
 353         }
 354
 355         /**
 356          * Returns the Language of the Message.
 357          *
 358          * @since 1.23
 359          *
 360          * @return Language
 361          */
 362         public function getLanguage() {
 363                 // Defaults to false which means current user language
 364                 return $this->language ?: RequestContext::getMain()->getLanguage();
 365         }
 366
 367         /**
 368          * Factory function that is just wrapper for the real constructor. It is
 369          * intended to be used instead of the real constructor, because it allows
 370          * chaining method calls, while new objects don't.
 371          *
 372          * @since 1.17
 373          *
 374          * @param string|string[]|MessageSpecifier $key
 375          * @param mixed $param,... Parameters as strings.
 376          *
 377          * @return Message
 378          */
 379         public static function newFromKey( $key /*...*/ ) {
 380                 $params = func_get_args();
 381                 array_shift( $params );
 382                 return new self( $key, $params );
 383         }
 384
 385         /**
 386          * Factory function accepting multiple message keys and returning a message instance
 387          * for the first message which is non-empty. If all messages are empty then an
 388          * instance of the first message key is returned.
 389          *
 390          * @since 1.18
 391          *
 392          * @param string|string[] $keys,... Message keys, or first argument as an array of all the
 393          * message keys.
 394          *
 395          * @return Message
 396          */
 397         public static function newFallbackSequence( /*...*/ ) {
 398                 $keys = func_get_args();
 399                 if ( func_num_args() == 1 ) {
 400                         if ( is_array( $keys[0] ) ) {
 401                                 // Allow an array to be passed as the first argument instead
 402                                 $keys = array_values( $keys[0] );
 403                         } else {
 404                                 // Optimize a single string to not need special fallback handling
 405                                 $keys = $keys[0];
 406                         }
 407                 }
 408                 return new self( $keys );
 409         }
 410
 411         /**
 412          * Get a title object for a mediawiki message, where it can be found in the mediawiki namespace.
 413          * The title will be for the current language, if the message key is in
 414          * $wgForceUIMsgAsContentMsg it will be append with the language code (except content
 415          * language), because Message::inContentLanguage will also return in user language.
 416          *
 417          * @see $wgForceUIMsgAsContentMsg
 418          * @return Title
 419          * @since 1.26
 420          */
 421         public function getTitle() {
 422                 global $wgContLang, $wgForceUIMsgAsContentMsg;
 423
 424                 $code = $this->getLanguage()->getCode();
 425                 $title = $this->key;
 426                 if (
 427                         $wgContLang->getCode() !== $code
 428                         && in_array( $this->key, (array)$wgForceUIMsgAsContentMsg )
 429                 ) {
 430                         $title .= '/' . $code;
 431                 }
 432
 433                 return Title::makeTitle( NS_MEDIAWIKI, $wgContLang->ucfirst( strtr( $title, ' ', '_' ) ) );
 434         }
 435
 436         /**
 437          * Adds parameters to the parameter list of this message.
 438          *
 439          * @since 1.17
 440          *
 441          * @param mixed ... Parameters as strings, or a single argument that is
 442          * an array of strings.
 443          *
 444          * @return Message $this
 445          */
 446         public function params( /*...*/ ) {
 447                 $args = func_get_args();
 448                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 449                         $args = $args[0];
 450                 }
 451                 $args_values = array_values( $args );
 452                 $this->parameters = array_merge( $this->parameters, $args_values );
 453                 return $this;
 454         }
 455
 456         /**
 457          * Add parameters that are substituted after parsing or escaping.
 458          * In other words the parsing process cannot access the contents
 459          * of this type of parameter, and you need to make sure it is
 460          * sanitized beforehand.  The parser will see "$n", instead.
 461          *
 462          * @since 1.17
 463          *
 464          * @param mixed $params,... Raw parameters as strings, or a single argument that is
 465          * an array of raw parameters.
 466          *
 467          * @return Message $this
 468          */
 469         public function rawParams( /*...*/ ) {
 470                 $params = func_get_args();
 471                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 472                         $params = $params[0];
 473                 }
 474                 foreach ( $params as $param ) {
 475                         $this->parameters[] = self::rawParam( $param );
 476                 }
 477                 return $this;
 478         }
 479
 480         /**
 481          * Add parameters that are numeric and will be passed through
 482          * Language::formatNum before substitution
 483          *
 484          * @since 1.18
 485          *
 486          * @param mixed $param,... Numeric parameters, or a single argument that is
 487          * an array of numeric parameters.
 488          *
 489          * @return Message $this
 490          */
 491         public function numParams( /*...*/ ) {
 492                 $params = func_get_args();
 493                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 494                         $params = $params[0];
 495                 }
 496                 foreach ( $params as $param ) {
 497                         $this->parameters[] = self::numParam( $param );
 498                 }
 499                 return $this;
 500         }
 501
 502         /**
 503          * Add parameters that are durations of time and will be passed through
 504          * Language::formatDuration before substitution
 505          *
 506          * @since 1.22
 507          *
 508          * @param int|int[] $param,... Duration parameters, or a single argument that is
 509          * an array of duration parameters.
 510          *
 511          * @return Message $this
 512          */
 513         public function durationParams( /*...*/ ) {
 514                 $params = func_get_args();
 515                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 516                         $params = $params[0];
 517                 }
 518                 foreach ( $params as $param ) {
 519                         $this->parameters[] = self::durationParam( $param );
 520                 }
 521                 return $this;
 522         }
 523
 524         /**
 525          * Add parameters that are expiration times and will be passed through
 526          * Language::formatExpiry before substitution
 527          *
 528          * @since 1.22
 529          *
 530          * @param string|string[] $param,... Expiry parameters, or a single argument that is
 531          * an array of expiry parameters.
 532          *
 533          * @return Message $this
 534          */
 535         public function expiryParams( /*...*/ ) {
 536                 $params = func_get_args();
 537                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 538                         $params = $params[0];
 539                 }
 540                 foreach ( $params as $param ) {
 541                         $this->parameters[] = self::expiryParam( $param );
 542                 }
 543                 return $this;
 544         }
 545
 546         /**
 547          * Add parameters that are time periods and will be passed through
 548          * Language::formatTimePeriod before substitution
 549          *
 550          * @since 1.22
 551          *
 552          * @param int|int[] $param,... Time period parameters, or a single argument that is
 553          * an array of time period parameters.
 554          *
 555          * @return Message $this
 556          */
 557         public function timeperiodParams( /*...*/ ) {
 558                 $params = func_get_args();
 559                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 560                         $params = $params[0];
 561                 }
 562                 foreach ( $params as $param ) {
 563                         $this->parameters[] = self::timeperiodParam( $param );
 564                 }
 565                 return $this;
 566         }
 567
 568         /**
 569          * Add parameters that are file sizes and will be passed through
 570          * Language::formatSize before substitution
 571          *
 572          * @since 1.22
 573          *
 574          * @param int|int[] $param,... Size parameters, or a single argument that is
 575          * an array of size parameters.
 576          *
 577          * @return Message $this
 578          */
 579         public function sizeParams( /*...*/ ) {
 580                 $params = func_get_args();
 581                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 582                         $params = $params[0];
 583                 }
 584                 foreach ( $params as $param ) {
 585                         $this->parameters[] = self::sizeParam( $param );
 586                 }
 587                 return $this;
 588         }
 589
 590         /**
 591          * Add parameters that are bitrates and will be passed through
 592          * Language::formatBitrate before substitution
 593          *
 594          * @since 1.22
 595          *
 596          * @param int|int[] $param,... Bit rate parameters, or a single argument that is
 597          * an array of bit rate parameters.
 598          *
 599          * @return Message $this
 600          */
 601         public function bitrateParams( /*...*/ ) {
 602                 $params = func_get_args();
 603                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 604                         $params = $params[0];
 605                 }
 606                 foreach ( $params as $param ) {
 607                         $this->parameters[] = self::bitrateParam( $param );
 608                 }
 609                 return $this;
 610         }
 611
 612         /**
 613          * Add parameters that are plaintext and will be passed through without
 614          * the content being evaluated.  Plaintext parameters are not valid as
 615          * arguments to parser functions. This differs from self::rawParams in
 616          * that the Message class handles escaping to match the output format.
 617          *
 618          * @since 1.25
 619          *
 620          * @param string|string[] $param,... plaintext parameters, or a single argument that is
 621          * an array of plaintext parameters.
 622          *
 623          * @return Message $this
 624          */
 625         public function plaintextParams( /*...*/ ) {
 626                 $params = func_get_args();
 627                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 628                         $params = $params[0];
 629                 }
 630                 foreach ( $params as $param ) {
 631                         $this->parameters[] = self::plaintextParam( $param );
 632                 }
 633                 return $this;
 634         }
 635
 636         /**
 637          * Set the language and the title from a context object
 638          *
 639          * @since 1.19
 640          *
 641          * @param IContextSource $context
 642          *
 643          * @return Message $this
 644          */
 645         public function setContext( IContextSource $context ) {
 646                 $this->inLanguage( $context->getLanguage() );
 647                 $this->title( $context->getTitle() );
 648                 $this->interface = true;
 649
 650                 return $this;
 651         }
 652
 653         /**
 654          * Request the message in any language that is supported.
 655          *
 656          * As a side effect interface message status is unconditionally
 657          * turned off.
 658          *
 659          * @since 1.17
 660          * @param Language|string $lang Language code or Language object.
 661          * @return Message $this
 662          * @throws MWException
 663          */
 664         public function inLanguage( $lang ) {
 665                 if ( $lang instanceof Language ) {
 666                         $this->language = $lang;
 667                 } elseif ( is_string( $lang ) ) {
 668                         if ( !$this->language instanceof Language || $this->language->getCode() != $lang ) {
 669                                 $this->language = Language::factory( $lang );
 670                         }
 671                 } elseif ( $lang instanceof StubUserLang ) {
 672                         $this->language = false;
 673                 } else {
 674                         $type = gettype( $lang );
 675                         throw new MWException( __METHOD__ . " must be "
 676                                 . "passed a String or Language object; $type given"
 677                         );
 678                 }
 679                 $this->message = null;
 680                 $this->interface = false;
 681                 return $this;
 682         }
 683
 684         /**
 685          * Request the message in the wiki's content language,
 686          * unless it is disabled for this message.
 687          *
 688          * @since 1.17
 689          * @see $wgForceUIMsgAsContentMsg
 690          *
 691          * @return Message $this
 692          */
 693         public function inContentLanguage() {
 694                 global $wgForceUIMsgAsContentMsg;
 695                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 696                         return $this;
 697                 }
 698
 699                 global $wgContLang;
 700                 $this->inLanguage( $wgContLang );
 701                 return $this;
 702         }
 703
 704         /**
 705          * Allows manipulating the interface message flag directly.
 706          * Can be used to restore the flag after setting a language.
 707          *
 708          * @since 1.20
 709          *
 710          * @param bool $interface
 711          *
 712          * @return Message $this
 713          */
 714         public function setInterfaceMessageFlag( $interface ) {
 715                 $this->interface = (bool)$interface;
 716                 return $this;
 717         }
 718
 719         /**
 720          * Enable or disable database use.
 721          *
 722          * @since 1.17
 723          *
 724          * @param bool $useDatabase
 725          *
 726          * @return Message $this
 727          */
 728         public function useDatabase( $useDatabase ) {
 729                 $this->useDatabase = (bool)$useDatabase;
 730                 return $this;
 731         }
 732
 733         /**
 734          * Set the Title object to use as context when transforming the message
 735          *
 736          * @since 1.18
 737          *
 738          * @param Title $title
 739          *
 740          * @return Message $this
 741          */
 742         public function title( $title ) {
 743                 $this->title = $title;
 744                 return $this;
 745         }
 746
 747         /**
 748          * Returns the message as a Content object.
 749          *
 750          * @return Content
 751          */
 752         public function content() {
 753                 if ( !$this->content ) {
 754                         $this->content = new MessageContent( $this );
 755                 }
 756
 757                 return $this->content;
 758         }
 759
 760         /**
 761          * Returns the message parsed from wikitext to HTML.
 762          *
 763          * @since 1.17
 764          *
 765          * @return string HTML
 766          */
 767         public function toString() {
 768                 $string = $this->fetchMessage();
 769
 770                 if ( $string === false ) {
 771                         if ( $this->format === 'plain' || $this->format === 'text' ) {
 772                                 return '<' . $this->key . '>';
 773                         }
 774                         return '&lt;' . htmlspecialchars( $this->key ) . '&gt;';
 775                 }
 776
 777                 # Replace $* with a list of parameters for &uselang=qqx.
 778                 if ( strpos( $string, '$*' ) !== false ) {
 779                         $paramlist = '';
 780                         if ( $this->parameters !== [] ) {
 781                                 $paramlist = ': $' . implode( ', $', range( 1, count( $this->parameters ) ) );
 782                         }
 783                         $string = str_replace( '$*', $paramlist, $string );
 784                 }
 785
 786                 # Replace parameters before text parsing
 787                 $string = $this->replaceParameters( $string, 'before' );
 788
 789                 # Maybe transform using the full parser
 790                 if ( $this->format === 'parse' ) {
 791                         $string = $this->parseText( $string );
 792                         $string = Parser::stripOuterParagraph( $string );
 793                 } elseif ( $this->format === 'block-parse' ) {
 794                         $string = $this->parseText( $string );
 795                 } elseif ( $this->format === 'text' ) {
 796                         $string = $this->transformText( $string );
 797                 } elseif ( $this->format === 'escaped' ) {
 798                         $string = $this->transformText( $string );
 799                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 800                 }
 801
 802                 # Raw parameter replacement
 803                 $string = $this->replaceParameters( $string, 'after' );
 804
 805                 return $string;
 806         }
 807
 808         /**
 809          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 810          *     $foo = new Message( $key );
 811          *     $string = "<abbr>$foo</abbr>";
 812          *
 813          * @since 1.18
 814          *
 815          * @return string
 816          */
 817         public function __toString() {
 818                 // PHP doesn't allow __toString to throw exceptions and will
 819                 // trigger a fatal error if it does. So, catch any exceptions.
 820
 821                 try {
 822                         return $this->toString();
 823                 } catch ( Exception $ex ) {
 824                         try {
 825                                 trigger_error( "Exception caught in " . __METHOD__ . " (message " . $this->key . "): "
 826                                         . $ex, E_USER_WARNING );
 827                         } catch ( Exception $ex ) {
 828                                 // Doh! Cause a fatal error after all?
 829                         }
 830
 831                         if ( $this->format === 'plain' || $this->format === 'text' ) {
 832                                 return '<' . $this->key . '>';
 833                         }
 834                         return '&lt;' . htmlspecialchars( $this->key ) . '&gt;';
 835                 }
 836         }
 837
 838         /**
 839          * Fully parse the text from wikitext to HTML.
 840          *
 841          * @since 1.17
 842          *
 843          * @return string Parsed HTML.
 844          */
 845         public function parse() {
 846                 $this->format = 'parse';
 847                 return $this->toString();
 848         }
 849
 850         /**
 851          * Returns the message text. {{-transformation is done.
 852          *
 853          * @since 1.17
 854          *
 855          * @return string Unescaped message text.
 856          */
 857         public function text() {
 858                 $this->format = 'text';
 859                 return $this->toString();
 860         }
 861
 862         /**
 863          * Returns the message text as-is, only parameters are substituted.
 864          *
 865          * @since 1.17
 866          *
 867          * @return string Unescaped untransformed message text.
 868          */
 869         public function plain() {
 870                 $this->format = 'plain';
 871                 return $this->toString();
 872         }
 873
 874         /**
 875          * Returns the parsed message text which is always surrounded by a block element.
 876          *
 877          * @since 1.17
 878          *
 879          * @return string HTML
 880          */
 881         public function parseAsBlock() {
 882                 $this->format = 'block-parse';
 883                 return $this->toString();
 884         }
 885
 886         /**
 887          * Returns the message text. {{-transformation is done and the result
 888          * is escaped excluding any raw parameters.
 889          *
 890          * @since 1.17
 891          *
 892          * @return string Escaped message text.
 893          */
 894         public function escaped() {
 895                 $this->format = 'escaped';
 896                 return $this->toString();
 897         }
 898
 899         /**
 900          * Check whether a message key has been defined currently.
 901          *
 902          * @since 1.17
 903          *
 904          * @return bool
 905          */
 906         public function exists() {
 907                 return $this->fetchMessage() !== false;
 908         }
 909
 910         /**
 911          * Check whether a message does not exist, or is an empty string
 912          *
 913          * @since 1.18
 914          * @todo FIXME: Merge with isDisabled()?
 915          *
 916          * @return bool
 917          */
 918         public function isBlank() {
 919                 $message = $this->fetchMessage();
 920                 return $message === false || $message === '';
 921         }
 922
 923         /**
 924          * Check whether a message does not exist, is an empty string, or is "-".
 925          *
 926          * @since 1.18
 927          *
 928          * @return bool
 929          */
 930         public function isDisabled() {
 931                 $message = $this->fetchMessage();
 932                 return $message === false || $message === '' || $message === '-';
 933         }
 934
 935         /**
 936          * @since 1.17
 937          *
 938          * @param mixed $raw
 939          *
 940          * @return array Array with a single "raw" key.
 941          */
 942         public static function rawParam( $raw ) {
 943                 return [ 'raw' => $raw ];
 944         }
 945
 946         /**
 947          * @since 1.18
 948          *
 949          * @param mixed $num
 950          *
 951          * @return array Array with a single "num" key.
 952          */
 953         public static function numParam( $num ) {
 954                 return [ 'num' => $num ];
 955         }
 956
 957         /**
 958          * @since 1.22
 959          *
 960          * @param int $duration
 961          *
 962          * @return int[] Array with a single "duration" key.
 963          */
 964         public static function durationParam( $duration ) {
 965                 return [ 'duration' => $duration ];
 966         }
 967
 968         /**
 969          * @since 1.22
 970          *
 971          * @param string $expiry
 972          *
 973          * @return string[] Array with a single "expiry" key.
 974          */
 975         public static function expiryParam( $expiry ) {
 976                 return [ 'expiry' => $expiry ];
 977         }
 978
 979         /**
 980          * @since 1.22
 981          *
 982          * @param number $period
 983          *
 984          * @return number[] Array with a single "period" key.
 985          */
 986         public static function timeperiodParam( $period ) {
 987                 return [ 'period' => $period ];
 988         }
 989
 990         /**
 991          * @since 1.22
 992          *
 993          * @param int $size
 994          *
 995          * @return int[] Array with a single "size" key.
 996          */
 997         public static function sizeParam( $size ) {
 998                 return [ 'size' => $size ];
 999         }
1000
1001         /**
1002          * @since 1.22
1003          *
1004          * @param int $bitrate
1005          *
1006          * @return int[] Array with a single "bitrate" key.
1007          */
1008         public static function bitrateParam( $bitrate ) {
1009                 return [ 'bitrate' => $bitrate ];
1010         }
1011
1012         /**
1013          * @since 1.25
1014          *
1015          * @param string $plaintext
1016          *
1017          * @return string[] Array with a single "plaintext" key.
1018          */
1019         public static function plaintextParam( $plaintext ) {
1020                 return [ 'plaintext' => $plaintext ];
1021         }
1022
1023         /**
1024          * Substitutes any parameters into the message text.
1025          *
1026          * @since 1.17
1027          *
1028          * @param string $message The message text.
1029          * @param string $type Either "before" or "after".
1030          *
1031          * @return string
1032          */
1033         protected function replaceParameters( $message, $type = 'before' ) {
1034                 $replacementKeys = [];
1035                 foreach ( $this->parameters as $n => $param ) {
1036                         list( $paramType, $value ) = $this->extractParam( $param );
1037                         if ( $type === $paramType ) {
1038                                 $replacementKeys['$' . ( $n + 1 )] = $value;
1039                         }
1040                 }
1041                 $message = strtr( $message, $replacementKeys );
1042                 return $message;
1043         }
1044
1045         /**
1046          * Extracts the parameter type and preprocessed the value if needed.
1047          *
1048          * @since 1.18
1049          *
1050          * @param mixed $param Parameter as defined in this class.
1051          *
1052          * @return array Array with the parameter type (either "before" or "after") and the value.
1053          */
1054         protected function extractParam( $param ) {
1055                 if ( is_array( $param ) ) {
1056                         if ( isset( $param['raw'] ) ) {
1057                                 return [ 'after', $param['raw'] ];
1058                         } elseif ( isset( $param['num'] ) ) {
1059                                 // Replace number params always in before step for now.
1060                                 // No support for combined raw and num params
1061                                 return [ 'before', $this->getLanguage()->formatNum( $param['num'] ) ];
1062                         } elseif ( isset( $param['duration'] ) ) {
1063                                 return [ 'before', $this->getLanguage()->formatDuration( $param['duration'] ) ];
1064                         } elseif ( isset( $param['expiry'] ) ) {
1065                                 return [ 'before', $this->getLanguage()->formatExpiry( $param['expiry'] ) ];
1066                         } elseif ( isset( $param['period'] ) ) {
1067                                 return [ 'before', $this->getLanguage()->formatTimePeriod( $param['period'] ) ];
1068                         } elseif ( isset( $param['size'] ) ) {
1069                                 return [ 'before', $this->getLanguage()->formatSize( $param['size'] ) ];
1070                         } elseif ( isset( $param['bitrate'] ) ) {
1071                                 return [ 'before', $this->getLanguage()->formatBitrate( $param['bitrate'] ) ];
1072                         } elseif ( isset( $param['plaintext'] ) ) {
1073                                 return [ 'after', $this->formatPlaintext( $param['plaintext'] ) ];
1074                         } else {
1075                                 $warning = 'Invalid parameter for message "' . $this->getKey() . '": ' .
1076                                         htmlspecialchars( serialize( $param ) );
1077                                 trigger_error( $warning, E_USER_WARNING );
1078                                 $e = new Exception;
1079                                 wfDebugLog( 'Bug58676', $warning . "\n" . $e->getTraceAsString() );
1080
1081                                 return [ 'before', '[INVALID]' ];
1082                         }
1083                 } elseif ( $param instanceof Message ) {
1084                         // Message objects should not be before parameters because
1085                         // then they'll get double escaped. If the message needs to be
1086                         // escaped, it'll happen right here when we call toString().
1087                         return [ 'after', $param->toString() ];
1088                 } else {
1089                         return [ 'before', $param ];
1090                 }
1091         }
1092
1093         /**
1094          * Wrapper for what ever method we use to parse wikitext.
1095          *
1096          * @since 1.17
1097          *
1098          * @param string $string Wikitext message contents.
1099          *
1100          * @return string Wikitext parsed into HTML.
1101          */
1102         protected function parseText( $string ) {
1103                 $out = MessageCache::singleton()->parse(
1104                         $string,
1105                         $this->title,
1106                         /*linestart*/true,
1107                         $this->interface,
1108                         $this->getLanguage()
1109                 );
1110
1111                 return $out instanceof ParserOutput ? $out->getText() : $out;
1112         }
1113
1114         /**
1115          * Wrapper for what ever method we use to {{-transform wikitext.
1116          *
1117          * @since 1.17
1118          *
1119          * @param string $string Wikitext message contents.
1120          *
1121          * @return string Wikitext with {{-constructs replaced with their values.
1122          */
1123         protected function transformText( $string ) {
1124                 return MessageCache::singleton()->transform(
1125                         $string,
1126                         $this->interface,
1127                         $this->getLanguage(),
1128                         $this->title
1129                 );
1130         }
1131
1132         /**
1133          * Wrapper for what ever method we use to get message contents.
1134          *
1135          * @since 1.17
1136          *
1137          * @return string
1138          * @throws MWException If message key array is empty.
1139          */
1140         protected function fetchMessage() {
1141                 if ( $this->message === null ) {
1142                         $cache = MessageCache::singleton();
1143
1144                         foreach ( $this->keysToTry as $key ) {
1145                                 $message = $cache->get( $key, $this->useDatabase, $this->getLanguage() );
1146                                 if ( $message !== false && $message !== '' ) {
1147                                         break;
1148                                 }
1149                         }
1150
1151                         // NOTE: The constructor makes sure keysToTry isn't empty,
1152                         //       so we know that $key and $message are initialized.
1153                         $this->key = $key;
1154                         $this->message = $message;
1155                 }
1156                 return $this->message;
1157         }
1158
1159         /**
1160          * Formats a message parameter wrapped with 'plaintext'. Ensures that
1161          * the entire string is displayed unchanged when displayed in the output
1162          * format.
1163          *
1164          * @since 1.25
1165          *
1166          * @param string $plaintext String to ensure plaintext output of
1167          *
1168          * @return string Input plaintext encoded for output to $this->format
1169          */
1170         protected function formatPlaintext( $plaintext ) {
1171                 switch ( $this->format ) {
1172                 case 'text':
1173                 case 'plain':
1174                         return $plaintext;
1175
1176                 case 'parse':
1177                 case 'block-parse':
1178                 case 'escaped':
1179                 default:
1180                         return htmlspecialchars( $plaintext, ENT_QUOTES );
1181
1182                 }
1183         }
1184 }
1185
1186 /**
1187  * Variant of the Message class.
1188  *
1189  * Rather than treating the message key as a lookup
1190  * value (which is passed to the MessageCache and
1191  * translated as necessary), a RawMessage key is
1192  * treated as the actual message.
1193  *
1194  * All other functionality (parsing, escaping, etc.)
1195  * is preserved.
1196  *
1197  * @since 1.21
1198  */
1199 class RawMessage extends Message {
1200
1201         /**
1202          * Call the parent constructor, then store the key as
1203          * the message.
1204          *
1205          * @see Message::__construct
1206          *
1207          * @param string $text Message to use.
1208          * @param array $params Parameters for the message.
1209          *
1210          * @throws InvalidArgumentException
1211          */
1212         public function __construct( $text, $params = [] ) {
1213                 if ( !is_string( $text ) ) {
1214                         throw new InvalidArgumentException( '$text must be a string' );
1215                 }
1216
1217                 parent::__construct( $text, $params );
1218
1219                 // The key is the message.
1220                 $this->message = $text;
1221         }
1222
1223         /**
1224          * Fetch the message (in this case, the key).
1225          *
1226          * @return string
1227          */
1228         public function fetchMessage() {
1229                 // Just in case the message is unset somewhere.
1230                 if ( $this->message === null ) {
1231                         $this->message = $this->key;
1232                 }
1233
1234                 return $this->message;
1235         }
1236
1237 }