languages/LanguageConverter.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @ingroup Language
  20  */
  21 use MediaWiki\MediaWikiServices;
  22
  23 use MediaWiki\Logger\LoggerFactory;
  24 use MediaWiki\Revision\RevisionRecord;
  25
  26 /**
  27  * Base class for language conversion.
  28  * @ingroup Language
  29  *
  30  * @author Zhengzhu Feng <zhengzhu@gmail.com>
  31  * @author fdcn <fdcn64@gmail.com>
  32  * @author shinjiman <shinjiman@gmail.com>
  33  * @author PhiLiP <philip.npc@gmail.com>
  34  */
  35 class LanguageConverter {
  36         /**
  37          * languages supporting variants
  38          * @since 1.20
  39          * @var array
  40          */
  41         public static $languagesWithVariants = [
  42                 'en',
  43                 'crh',
  44                 'gan',
  45                 'iu',
  46                 'kk',
  47                 'ku',
  48                 'shi',
  49                 'sr',
  50                 'tg',
  51                 'uz',
  52                 'zh',
  53         ];
  54
  55         public $mMainLanguageCode;
  56
  57         /**
  58          * @var string[]
  59          */
  60         public $mVariants;
  61         public $mVariantFallbacks;
  62         public $mVariantNames;
  63         public $mTablesLoaded = false;
  64
  65         /**
  66          * @var ReplacementArray[]|bool[]
  67          */
  68         public $mTables;
  69
  70         // 'bidirectional' 'unidirectional' 'disable' for each variant
  71         public $mManualLevel;
  72
  73         public $mLangObj;
  74         public $mFlags;
  75         public $mDescCodeSep = ':', $mDescVarSep = ';';
  76         public $mUcfirst = false;
  77         public $mConvRuleTitle = false;
  78         public $mURLVariant;
  79         public $mUserVariant;
  80         public $mHeaderVariant;
  81         public $mMaxDepth = 10;
  82         public $mVarSeparatorPattern;
  83
  84         const CACHE_VERSION_KEY = 'VERSION 7';
  85
  86         /**
  87          * @param Language $langobj
  88          * @param string $maincode The main language code of this language
  89          * @param string[] $variants The supported variants of this language
  90          * @param array $variantfallbacks The fallback language of each variant
  91          * @param array $flags Defining the custom strings that maps to the flags
  92          * @param array $manualLevel Limit for supported variants
  93          */
  94         public function __construct( Language $langobj, $maincode, $variants = [],
  95                                                                 $variantfallbacks = [], $flags = [],
  96                                                                 $manualLevel = [] ) {
  97                 global $wgDisabledVariants;
  98                 $this->mLangObj = $langobj;
  99                 $this->mMainLanguageCode = $maincode;
 100                 $this->mVariants = array_diff( $variants, $wgDisabledVariants );
 101                 $this->mVariantFallbacks = $variantfallbacks;
 102                 $this->mVariantNames = Language::fetchLanguageNames();
 103                 $defaultflags = [
 104                         // 'S' show converted text
 105                         // '+' add rules for alltext
 106                         // 'E' the gave flags is error
 107                         // these flags above are reserved for program
 108                         'A' => 'A',   // add rule for convert code (all text convert)
 109                         'T' => 'T',   // title convert
 110                         'R' => 'R',   // raw content
 111                         'D' => 'D',   // convert description (subclass implement)
 112                         '-' => '-',   // remove convert (not implement)
 113                         'H' => 'H',   // add rule for convert code (but no display in placed code)
 114                         'N' => 'N',   // current variant name
 115                 ];
 116                 $this->mFlags = array_merge( $defaultflags, $flags );
 117                 foreach ( $this->mVariants as $v ) {
 118                         if ( array_key_exists( $v, $manualLevel ) ) {
 119                                 $this->mManualLevel[$v] = $manualLevel[$v];
 120                         } else {
 121                                 $this->mManualLevel[$v] = 'bidirectional';
 122                         }
 123                         $this->mFlags[$v] = $v;
 124                 }
 125         }
 126
 127         /**
 128          * Get all valid variants.
 129          * Call this instead of using $this->mVariants directly.
 130          *
 131          * @return string[] Contains all valid variants
 132          */
 133         public function getVariants() {
 134                 return $this->mVariants;
 135         }
 136
 137         /**
 138          * In case some variant is not defined in the markup, we need
 139          * to have some fallback. For example, in zh, normally people
 140          * will define zh-hans and zh-hant, but less so for zh-sg or zh-hk.
 141          * when zh-sg is preferred but not defined, we will pick zh-hans
 142          * in this case. Right now this is only used by zh.
 143          *
 144          * @param string $variant The language code of the variant
 145          * @return string|array The code of the fallback language or the
 146          *   main code if there is no fallback
 147          */
 148         public function getVariantFallbacks( $variant ) {
 149                 return $this->mVariantFallbacks[$variant] ?? $this->mMainLanguageCode;
 150         }
 151
 152         /**
 153          * Get the title produced by the conversion rule.
 154          * @return string The converted title text
 155          */
 156         public function getConvRuleTitle() {
 157                 return $this->mConvRuleTitle;
 158         }
 159
 160         /**
 161          * Get preferred language variant.
 162          * @return string The preferred language code
 163          */
 164         public function getPreferredVariant() {
 165                 global $wgDefaultLanguageVariant, $wgUser;
 166
 167                 $req = $this->getURLVariant();
 168
 169                 Hooks::run( 'GetLangPreferredVariant', [ &$req ] );
 170
 171                 if ( $wgUser->isSafeToLoad() && $wgUser->isLoggedIn() && !$req ) {
 172                         $req = $this->getUserVariant();
 173                 } elseif ( !$req ) {
 174                         $req = $this->getHeaderVariant();
 175                 }
 176
 177                 if ( $wgDefaultLanguageVariant && !$req ) {
 178                         $req = $this->validateVariant( $wgDefaultLanguageVariant );
 179                 }
 180
 181                 $req = $this->validateVariant( $req );
 182
 183                 // This function, unlike the other get*Variant functions, is
 184                 // not memoized (i.e. there return value is not cached) since
 185                 // new information might appear during processing after this
 186                 // is first called.
 187                 if ( $req ) {
 188                         return $req;
 189                 }
 190                 return $this->mMainLanguageCode;
 191         }
 192
 193         /**
 194          * Get default variant.
 195          * This function would not be affected by user's settings
 196          * @return string The default variant code
 197          */
 198         public function getDefaultVariant() {
 199                 global $wgDefaultLanguageVariant;
 200
 201                 $req = $this->getURLVariant();
 202
 203                 if ( !$req ) {
 204                         $req = $this->getHeaderVariant();
 205                 }
 206
 207                 if ( $wgDefaultLanguageVariant && !$req ) {
 208                         $req = $this->validateVariant( $wgDefaultLanguageVariant );
 209                 }
 210
 211                 if ( $req ) {
 212                         return $req;
 213                 }
 214                 return $this->mMainLanguageCode;
 215         }
 216
 217         /**
 218          * Validate the variant and return an appropriate strict internal
 219          * variant code if one exists.  Compare to Language::hasVariant()
 220          * which does a strict test.
 221          *
 222          * @param string|null $variant The variant to validate
 223          * @return mixed Returns an equivalent valid variant code if possible,
 224          *   null otherwise
 225          */
 226         public function validateVariant( $variant = null ) {
 227                 if ( $variant === null ) {
 228                         return null;
 229                 }
 230                 // Our internal variants are always lower-case; the variant we
 231                 // are validating may have mixed case.
 232                 $variant = LanguageCode::replaceDeprecatedCodes( strtolower( $variant ) );
 233                 if ( in_array( $variant, $this->mVariants ) ) {
 234                         return $variant;
 235                 }
 236                 // Browsers are supposed to use BCP 47 standard in the
 237                 // Accept-Language header, but not all of our internal
 238                 // mediawiki variant codes are BCP 47.  Map BCP 47 code
 239                 // to our internal code.
 240                 foreach ( $this->mVariants as $v ) {
 241                         // Case-insensitive match (BCP 47 is mixed case)
 242                         if ( strtolower( LanguageCode::bcp47( $v ) ) === $variant ) {
 243                                 return $v;
 244                         }
 245                 }
 246                 return null;
 247         }
 248
 249         /**
 250          * Get the variant specified in the URL
 251          *
 252          * @return mixed Variant if one found, null otherwise
 253          */
 254         public function getURLVariant() {
 255                 global $wgRequest;
 256
 257                 if ( $this->mURLVariant ) {
 258                         return $this->mURLVariant;
 259                 }
 260
 261                 // see if the preference is set in the request
 262                 $ret = $wgRequest->getText( 'variant' );
 263
 264                 if ( !$ret ) {
 265                         $ret = $wgRequest->getVal( 'uselang' );
 266                 }
 267
 268                 $this->mURLVariant = $this->validateVariant( $ret );
 269                 return $this->mURLVariant;
 270         }
 271
 272         /**
 273          * Determine if the user has a variant set.
 274          *
 275          * @return mixed Variant if one found, null otherwise
 276          */
 277         protected function getUserVariant() {
 278                 global $wgUser;
 279
 280                 // memoizing this function wreaks havoc on parserTest.php
 281                 /*
 282                 if ( $this->mUserVariant ) {
 283                         return $this->mUserVariant;
 284                 }
 285                 */
 286
 287                 // Get language variant preference from logged in users
 288                 // Don't call this on stub objects because that causes infinite
 289                 // recursion during initialisation
 290                 if ( !$wgUser->isSafeToLoad() ) {
 291                         return false;
 292                 }
 293                 if ( $wgUser->isLoggedIn() ) {
 294                         if (
 295                                 $this->mMainLanguageCode ==
 296                                 MediaWikiServices::getInstance()->getContentLanguage()->getCode()
 297                         ) {
 298                                 $ret = $wgUser->getOption( 'variant' );
 299                         } else {
 300                                 $ret = $wgUser->getOption( 'variant-' . $this->mMainLanguageCode );
 301                         }
 302                 } else {
 303                         // figure out user lang without constructing wgLang to avoid
 304                         // infinite recursion
 305                         $ret = $wgUser->getOption( 'language' );
 306                 }
 307
 308                 $this->mUserVariant = $this->validateVariant( $ret );
 309                 return $this->mUserVariant;
 310         }
 311
 312         /**
 313          * Determine the language variant from the Accept-Language header.
 314          *
 315          * @return mixed Variant if one found, null otherwise
 316          */
 317         protected function getHeaderVariant() {
 318                 global $wgRequest;
 319
 320                 if ( $this->mHeaderVariant ) {
 321                         return $this->mHeaderVariant;
 322                 }
 323
 324                 // See if some supported language variant is set in the
 325                 // HTTP header.
 326                 $languages = array_keys( $wgRequest->getAcceptLang() );
 327                 if ( empty( $languages ) ) {
 328                         return null;
 329                 }
 330
 331                 $fallbackLanguages = [];
 332                 foreach ( $languages as $language ) {
 333                         $this->mHeaderVariant = $this->validateVariant( $language );
 334                         if ( $this->mHeaderVariant ) {
 335                                 break;
 336                         }
 337
 338                         // To see if there are fallbacks of current language.
 339                         // We record these fallback variants, and process
 340                         // them later.
 341                         $fallbacks = $this->getVariantFallbacks( $language );
 342                         if ( is_string( $fallbacks ) && $fallbacks !== $this->mMainLanguageCode ) {
 343                                 $fallbackLanguages[] = $fallbacks;
 344                         } elseif ( is_array( $fallbacks ) ) {
 345                                 $fallbackLanguages =
 346                                         array_merge( $fallbackLanguages, $fallbacks );
 347                         }
 348                 }
 349
 350                 if ( !$this->mHeaderVariant ) {
 351                         // process fallback languages now
 352                         $fallback_languages = array_unique( $fallbackLanguages );
 353                         foreach ( $fallback_languages as $language ) {
 354                                 $this->mHeaderVariant = $this->validateVariant( $language );
 355                                 if ( $this->mHeaderVariant ) {
 356                                         break;
 357                                 }
 358                         }
 359                 }
 360
 361                 return $this->mHeaderVariant;
 362         }
 363
 364         /**
 365          * Dictionary-based conversion.
 366          * This function would not parse the conversion rules.
 367          * If you want to parse rules, try to use convert() or
 368          * convertTo().
 369          *
 370          * @param string $text The text to be converted
 371          * @param bool|string $toVariant The target language code
 372          * @return string The converted text
 373          */
 374         public function autoConvert( $text, $toVariant = false ) {
 375                 $this->loadTables();
 376
 377                 if ( !$toVariant ) {
 378                         $toVariant = $this->getPreferredVariant();
 379                         if ( !$toVariant ) {
 380                                 return $text;
 381                         }
 382                 }
 383
 384                 if ( $this->guessVariant( $text, $toVariant ) ) {
 385                         return $text;
 386                 }
 387                 /* we convert everything except:
 388                    1. HTML markups (anything between < and >)
 389                    2. HTML entities
 390                    3. placeholders created by the parser
 391                    IMPORTANT: Beware of failure from pcre.backtrack_limit (T124404).
 392                    Minimize use of backtracking where possible.
 393                 */
 394                 static $reg;
 395                 if ( $reg === null ) {
 396                         $marker = '|' . Parser::MARKER_PREFIX . '[^\x7f]++\x7f';
 397
 398                         // this one is needed when the text is inside an HTML markup
 399                         $htmlfix = '|<[^>\004]++(?=\004$)|^[^<>]*+>';
 400
 401                         // Optimize for the common case where these tags have
 402                         // few or no children. Thus try and possesively get as much as
 403                         // possible, and only engage in backtracking when we hit a '<'.
 404
 405                         // disable convert to variants between <code> tags
 406                         $codefix = '<code>[^<]*+(?:(?:(?!<\/code>).)[^<]*+)*+<\/code>|';
 407                         // disable conversion of <script> tags
 408                         $scriptfix = '<script[^>]*+>[^<]*+(?:(?:(?!<\/script>).)[^<]*+)*+<\/script>|';
 409                         // disable conversion of <pre> tags
 410                         $prefix = '<pre[^>]*+>[^<]*+(?:(?:(?!<\/pre>).)[^<]*+)*+<\/pre>|';
 411                         // The "|.*+)" at the end, is in case we missed some part of html syntax,
 412                         // we will fail securely (hopefully) by matching the rest of the string.
 413                         $htmlFullTag = '<(?:[^>=]*+(?>[^>=]*+=\s*+(?:"[^"]*"|\'[^\']*\'|[^\'">\s]*+))*+[^>=]*+>|.*+)|';
 414
 415                         $reg = '/' . $codefix . $scriptfix . $prefix . $htmlFullTag .
 416                                  '&[a-zA-Z#][a-z0-9]++;' . $marker . $htmlfix . '|\004$/s';
 417                 }
 418                 $startPos = 0;
 419                 $sourceBlob = '';
 420                 $literalBlob = '';
 421
 422                 // Guard against delimiter nulls in the input
 423                 // (should never happen: see T159174)
 424                 $text = str_replace( "\000", '', $text );
 425                 $text = str_replace( "\004", '', $text );
 426
 427                 $markupMatches = null;
 428                 $elementMatches = null;
 429
 430                 // We add a marker (\004) at the end of text, to ensure we always match the
 431                 // entire text (Otherwise, pcre.backtrack_limit might cause silent failure)
 432                 $textWithMarker = $text . "\004";
 433                 while ( $startPos < strlen( $text ) ) {
 434                         if ( preg_match( $reg, $textWithMarker, $markupMatches, PREG_OFFSET_CAPTURE, $startPos ) ) {
 435                                 $elementPos = $markupMatches[0][1];
 436                                 $element = $markupMatches[0][0];
 437                                 if ( $element === "\004" ) {
 438                                         // We hit the end.
 439                                         $elementPos = strlen( $text );
 440                                         $element = '';
 441                                 } elseif ( substr( $element, -1 ) === "\004" ) {
 442                                         // This can sometimes happen if we have
 443                                         // unclosed html tags (For example
 444                                         // when converting a title attribute
 445                                         // during a recursive call that contains
 446                                         // a &lt; e.g. <div title="&lt;">.
 447                                         $element = substr( $element, 0, -1 );
 448                                 }
 449                         } else {
 450                                 // If we hit here, then Language Converter could be tricked
 451                                 // into doing an XSS, so we refuse to translate.
 452                                 // If non-crazy input manages to reach this code path,
 453                                 // we should consider it a bug.
 454                                 $log = LoggerFactory::getInstance( 'languageconverter' );
 455                                 $log->error( "Hit pcre.backtrack_limit in " . __METHOD__
 456                                         . ". Disabling language conversion for this page.",
 457                                         [
 458                                                 "method" => __METHOD__,
 459                                                 "variant" => $toVariant,
 460                                                 "startOfText" => substr( $text, 0, 500 )
 461                                         ]
 462                                 );
 463                                 return $text;
 464                         }
 465                         // Queue the part before the markup for translation in a batch
 466                         $sourceBlob .= substr( $text, $startPos, $elementPos - $startPos ) . "\000";
 467
 468                         // Advance to the next position
 469                         $startPos = $elementPos + strlen( $element );
 470
 471                         // Translate any alt or title attributes inside the matched element
 472                         if ( $element !== ''
 473                                 && preg_match( '/^(<[^>\s]*+)\s([^>]*+)(.*+)$/', $element, $elementMatches )
 474                         ) {
 475                                 // FIXME, this decodes entities, so if you have something
 476                                 // like <div title="foo&lt;bar"> the bar won't get
 477                                 // translated since after entity decoding it looks like
 478                                 // unclosed html and we call this method recursively
 479                                 // on attributes.
 480                                 $attrs = Sanitizer::decodeTagAttributes( $elementMatches[2] );
 481                                 // Ensure self-closing tags stay self-closing.
 482                                 $close = substr( $elementMatches[2], -1 ) === '/' ? ' /' : '';
 483                                 $changed = false;
 484                                 foreach ( [ 'title', 'alt' ] as $attrName ) {
 485                                         if ( !isset( $attrs[$attrName] ) ) {
 486                                                 continue;
 487                                         }
 488                                         $attr = $attrs[$attrName];
 489                                         // Don't convert URLs
 490                                         if ( !strpos( $attr, '://' ) ) {
 491                                                 $attr = $this->recursiveConvertTopLevel( $attr, $toVariant );
 492                                         }
 493
 494                                         if ( $attr !== $attrs[$attrName] ) {
 495                                                 $attrs[$attrName] = $attr;
 496                                                 $changed = true;
 497                                         }
 498                                 }
 499                                 if ( $changed ) {
 500                                         $element = $elementMatches[1] . Html::expandAttributes( $attrs ) .
 501                                                 $close . $elementMatches[3];
 502                                 }
 503                         }
 504                         $literalBlob .= $element . "\000";
 505                 }
 506
 507                 // Do the main translation batch
 508                 $translatedBlob = $this->translate( $sourceBlob, $toVariant );
 509
 510                 // Put the output back together
 511                 $translatedIter = StringUtils::explode( "\000", $translatedBlob );
 512                 $literalIter = StringUtils::explode( "\000", $literalBlob );
 513                 $output = '';
 514                 while ( $translatedIter->valid() && $literalIter->valid() ) {
 515                         $output .= $translatedIter->current();
 516                         $output .= $literalIter->current();
 517                         $translatedIter->next();
 518                         $literalIter->next();
 519                 }
 520
 521                 return $output;
 522         }
 523
 524         /**
 525          * Translate a string to a variant.
 526          * Doesn't parse rules or do any of that other stuff, for that use
 527          * convert() or convertTo().
 528          *
 529          * @param string $text Text to convert
 530          * @param string $variant Variant language code
 531          * @return string Translated text
 532          */
 533         public function translate( $text, $variant ) {
 534                 // If $text is empty or only includes spaces, do nothing
 535                 // Otherwise translate it
 536                 if ( trim( $text ) ) {
 537                         $this->loadTables();
 538                         $text = $this->mTables[$variant]->replace( $text );
 539                 }
 540                 return $text;
 541         }
 542
 543         /**
 544          * Call translate() to convert text to all valid variants.
 545          *
 546          * @param string $text The text to be converted
 547          * @return array Variant => converted text
 548          */
 549         public function autoConvertToAllVariants( $text ) {
 550                 $this->loadTables();
 551
 552                 $ret = [];
 553                 foreach ( $this->mVariants as $variant ) {
 554                         $ret[$variant] = $this->translate( $text, $variant );
 555                 }
 556
 557                 return $ret;
 558         }
 559
 560         /**
 561          * Apply manual conversion rules.
 562          *
 563          * @param ConverterRule $convRule
 564          */
 565         protected function applyManualConv( $convRule ) {
 566                 // Use syntax -{T|zh-cn:TitleCN; zh-tw:TitleTw}- to custom
 567                 // title conversion.
 568                 // T26072: $mConvRuleTitle was overwritten by other manual
 569                 // rule(s) not for title, this breaks the title conversion.
 570                 $newConvRuleTitle = $convRule->getTitle();
 571                 if ( $newConvRuleTitle ) {
 572                         // So I add an empty check for getTitle()
 573                         $this->mConvRuleTitle = $newConvRuleTitle;
 574                 }
 575
 576                 // merge/remove manual conversion rules to/from global table
 577                 $convTable = $convRule->getConvTable();
 578                 $action = $convRule->getRulesAction();
 579                 foreach ( $convTable as $variant => $pair ) {
 580                         $v = $this->validateVariant( $variant );
 581                         if ( !$v ) {
 582                                 continue;
 583                         }
 584
 585                         if ( $action == 'add' ) {
 586                                 // More efficient than array_merge(), about 2.5 times.
 587                                 foreach ( $pair as $from => $to ) {
 588                                         $this->mTables[$v]->setPair( $from, $to );
 589                                 }
 590                         } elseif ( $action == 'remove' ) {
 591                                 $this->mTables[$v]->removeArray( $pair );
 592                         }
 593                 }
 594         }
 595
 596         /**
 597          * Auto convert a Title object to a readable string in the
 598          * preferred variant.
 599          *
 600          * @param Title $title A object of Title
 601          * @return string Converted title text
 602          */
 603         public function convertTitle( $title ) {
 604                 $variant = $this->getPreferredVariant();
 605                 $index = $title->getNamespace();
 606                 if ( $index !== NS_MAIN ) {
 607                         $text = $this->convertNamespace( $index, $variant ) . ':';
 608                 } else {
 609                         $text = '';
 610                 }
 611                 $text .= $this->translate( $title->getText(), $variant );
 612                 return $text;
 613         }
 614
 615         /**
 616          * Get the namespace display name in the preferred variant.
 617          *
 618          * @param int $index Namespace id
 619          * @param string|null $variant Variant code or null for preferred variant
 620          * @return string Namespace name for display
 621          */
 622         public function convertNamespace( $index, $variant = null ) {
 623                 if ( $index === NS_MAIN ) {
 624                         return '';
 625                 }
 626
 627                 if ( $variant === null ) {
 628                         $variant = $this->getPreferredVariant();
 629                 }
 630
 631                 $cache = MediaWikiServices::getInstance()->getLocalServerObjectCache();
 632                 $key = $cache->makeKey( 'languageconverter', 'namespace-text', $index, $variant );
 633                 $nsVariantText = $cache->get( $key );
 634                 if ( $nsVariantText !== false ) {
 635                         return $nsVariantText;
 636                 }
 637
 638                 // First check if a message gives a converted name in the target variant.
 639                 $nsConvMsg = wfMessage( 'conversion-ns' . $index )->inLanguage( $variant );
 640                 if ( $nsConvMsg->exists() ) {
 641                         $nsVariantText = $nsConvMsg->plain();
 642                 }
 643
 644                 // Then check if a message gives a converted name in content language
 645                 // which needs extra translation to the target variant.
 646                 if ( $nsVariantText === false ) {
 647                         $nsConvMsg = wfMessage( 'conversion-ns' . $index )->inContentLanguage();
 648                         if ( $nsConvMsg->exists() ) {
 649                                 $nsVariantText = $this->translate( $nsConvMsg->plain(), $variant );
 650                         }
 651                 }
 652
 653                 if ( $nsVariantText === false ) {
 654                         // No message exists, retrieve it from the target variant's namespace names.
 655                         $langObj = $this->mLangObj->factory( $variant );
 656                         $nsVariantText = $langObj->getFormattedNsText( $index );
 657                 }
 658
 659                 $cache->set( $key, $nsVariantText, 60 );
 660
 661                 return $nsVariantText;
 662         }
 663
 664         /**
 665          * Convert text to different variants of a language. The automatic
 666          * conversion is done in autoConvert(). Here we parse the text
 667          * marked with -{}-, which specifies special conversions of the
 668          * text that can not be accomplished in autoConvert().
 669          *
 670          * Syntax of the markup:
 671          * -{code1:text1;code2:text2;...}-  or
 672          * -{flags|code1:text1;code2:text2;...}-  or
 673          * -{text}- in which case no conversion should take place for text
 674          *
 675          * @warning Glossary state is maintained between calls. Never feed this
 676          *   method input that hasn't properly been escaped as it may result in
 677          *   an XSS in subsequent calls, even if those subsequent calls properly
 678          *   escape things.
 679          * @param string $text Text to be converted, already html escaped.
 680          * @return string Converted text (html)
 681          */
 682         public function convert( $text ) {
 683                 $variant = $this->getPreferredVariant();
 684                 return $this->convertTo( $text, $variant );
 685         }
 686
 687         /**
 688          * Same as convert() except a extra parameter to custom variant.
 689          *
 690          * @param string $text Text to be converted, already html escaped
 691          * @param-taint $text exec_html
 692          * @param string $variant The target variant code
 693          * @return string Converted text
 694          * @return-taint escaped
 695          */
 696         public function convertTo( $text, $variant ) {
 697                 global $wgDisableLangConversion;
 698                 if ( $wgDisableLangConversion ) {
 699                         return $text;
 700                 }
 701                 // Reset converter state for a new converter run.
 702                 $this->mConvRuleTitle = false;
 703                 return $this->recursiveConvertTopLevel( $text, $variant );
 704         }
 705
 706         /**
 707          * Recursively convert text on the outside. Allow to use nested
 708          * markups to custom rules.
 709          *
 710          * @param string $text Text to be converted
 711          * @param string $variant The target variant code
 712          * @param int $depth Depth of recursion
 713          * @return string Converted text
 714          */
 715         protected function recursiveConvertTopLevel( $text, $variant, $depth = 0 ) {
 716                 $startPos = 0;
 717                 $out = '';
 718                 $length = strlen( $text );
 719                 $shouldConvert = !$this->guessVariant( $text, $variant );
 720                 $continue = 1;
 721
 722                 $noScript = '<script.*?>.*?<\/script>(*SKIP)(*FAIL)';
 723                 $noStyle = '<style.*?>.*?<\/style>(*SKIP)(*FAIL)';
 724                 // phpcs:ignore Generic.Files.LineLength
 725                 $noHtml = '<(?:[^>=]*+(?>[^>=]*+=\s*+(?:"[^"]*"|\'[^\']*\'|[^\'">\s]*+))*+[^>=]*+>|.*+)(*SKIP)(*FAIL)';
 726                 while ( $startPos < $length && $continue ) {
 727                         $continue = preg_match(
 728                                 // Only match -{ outside of html.
 729                                 "/$noScript|$noStyle|$noHtml|-\{/",
 730                                 $text,
 731                                 $m,
 732                                 PREG_OFFSET_CAPTURE,
 733                                 $startPos
 734                         );
 735
 736                         if ( !$continue ) {
 737                                 // No more markup, append final segment
 738                                 $fragment = substr( $text, $startPos );
 739                                 $out .= $shouldConvert ? $this->autoConvert( $fragment, $variant ) : $fragment;
 740                                 return $out;
 741                         }
 742
 743                         // Offset of the match of the regex pattern.
 744                         $pos = $m[0][1];
 745
 746                         // Append initial segment
 747                         $fragment = substr( $text, $startPos, $pos - $startPos );
 748                         $out .= $shouldConvert ? $this->autoConvert( $fragment, $variant ) : $fragment;
 749                         // -{ marker found, not in attribute
 750                         // Advance position up to -{ marker.
 751                         $startPos = $pos;
 752                         // Do recursive conversion
 753                         // Note: This passes $startPos by reference, and advances it.
 754                         $out .= $this->recursiveConvertRule( $text, $variant, $startPos, $depth + 1 );
 755                 }
 756                 return $out;
 757         }
 758
 759         /**
 760          * Recursively convert text on the inside.
 761          *
 762          * @param string $text Text to be converted
 763          * @param string $variant The target variant code
 764          * @param int &$startPos
 765          * @param int $depth Depth of recursion
 766          *
 767          * @throws MWException
 768          * @return string Converted text
 769          */
 770         protected function recursiveConvertRule( $text, $variant, &$startPos, $depth = 0 ) {
 771                 // Quick sanity check (no function calls)
 772                 if ( $text[$startPos] !== '-' || $text[$startPos + 1] !== '{' ) {
 773                         throw new MWException( __METHOD__ . ': invalid input string' );
 774                 }
 775
 776                 $startPos += 2;
 777                 $inner = '';
 778                 $warningDone = false;
 779                 $length = strlen( $text );
 780
 781                 while ( $startPos < $length ) {
 782                         $m = false;
 783                         preg_match( '/-\{|\}-/', $text, $m, PREG_OFFSET_CAPTURE, $startPos );
 784                         if ( !$m ) {
 785                                 // Unclosed rule
 786                                 break;
 787                         }
 788
 789                         $token = $m[0][0];
 790                         $pos = $m[0][1];
 791
 792                         // Markup found
 793                         // Append initial segment
 794                         $inner .= substr( $text, $startPos, $pos - $startPos );
 795
 796                         // Advance position
 797                         $startPos = $pos;
 798
 799                         switch ( $token ) {
 800                                 case '-{':
 801                                         // Check max depth
 802                                         if ( $depth >= $this->mMaxDepth ) {
 803                                                 $inner .= '-{';
 804                                                 if ( !$warningDone ) {
 805                                                         $inner .= '<span class="error">' .
 806                                                                 wfMessage( 'language-converter-depth-warning' )
 807                                                                         ->numParams( $this->mMaxDepth )->inContentLanguage()->text() .
 808                                                                 '</span>';
 809                                                         $warningDone = true;
 810                                                 }
 811                                                 $startPos += 2;
 812                                                 break;
 813                                         }
 814                                         // Recursively parse another rule
 815                                         $inner .= $this->recursiveConvertRule( $text, $variant, $startPos, $depth + 1 );
 816                                         break;
 817                                 case '}-':
 818                                         // Apply the rule
 819                                         $startPos += 2;
 820                                         $rule = new ConverterRule( $inner, $this );
 821                                         $rule->parse( $variant );
 822                                         $this->applyManualConv( $rule );
 823                                         return $rule->getDisplay();
 824                                 default:
 825                                         throw new MWException( __METHOD__ . ': invalid regex match' );
 826                         }
 827                 }
 828
 829                 // Unclosed rule
 830                 if ( $startPos < $length ) {
 831                         $inner .= substr( $text, $startPos );
 832                 }
 833                 $startPos = $length;
 834                 return '-{' . $this->autoConvert( $inner, $variant );
 835         }
 836
 837         /**
 838          * If a language supports multiple variants, it is possible that
 839          * non-existing link in one variant actually exists in another variant.
 840          * This function tries to find it. See e.g. LanguageZh.php
 841          * The input parameters may be modified upon return
 842          *
 843          * @param string &$link The name of the link
 844          * @param Title &$nt The title object of the link
 845          * @param bool $ignoreOtherCond To disable other conditions when
 846          *   we need to transclude a template or update a category's link
 847          */
 848         public function findVariantLink( &$link, &$nt, $ignoreOtherCond = false ) {
 849                 # If the article has already existed, there is no need to
 850                 # check it again, otherwise it may cause a fault.
 851                 if ( is_object( $nt ) && $nt->exists() ) {
 852                         return;
 853                 }
 854
 855                 global $wgDisableLangConversion, $wgDisableTitleConversion, $wgRequest;
 856                 $isredir = $wgRequest->getText( 'redirect', 'yes' );
 857                 $action = $wgRequest->getText( 'action' );
 858                 if ( $action == 'edit' && $wgRequest->getBool( 'redlink' ) ) {
 859                         $action = 'view';
 860                 }
 861                 $linkconvert = $wgRequest->getText( 'linkconvert', 'yes' );
 862                 $disableLinkConversion = $wgDisableLangConversion
 863                         || $wgDisableTitleConversion;
 864                 $linkBatch = new LinkBatch();
 865
 866                 $ns = NS_MAIN;
 867
 868                 if ( $disableLinkConversion ||
 869                         ( !$ignoreOtherCond &&
 870                                 ( $isredir == 'no'
 871                                         || $action == 'edit'
 872                                         || $action == 'submit'
 873                                         || $linkconvert == 'no' ) ) ) {
 874                         return;
 875                 }
 876
 877                 if ( is_object( $nt ) ) {
 878                         $ns = $nt->getNamespace();
 879                 }
 880
 881                 $variants = $this->autoConvertToAllVariants( $link );
 882                 if ( !$variants ) { // give up
 883                         return;
 884                 }
 885
 886                 $titles = [];
 887
 888                 foreach ( $variants as $v ) {
 889                         if ( $v != $link ) {
 890                                 $varnt = Title::newFromText( $v, $ns );
 891                                 if ( !is_null( $varnt ) ) {
 892                                         $linkBatch->addObj( $varnt );
 893                                         $titles[] = $varnt;
 894                                 }
 895                         }
 896                 }
 897
 898                 // fetch all variants in single query
 899                 $linkBatch->execute();
 900
 901                 foreach ( $titles as $varnt ) {
 902                         if ( $varnt->getArticleID() > 0 ) {
 903                                 $nt = $varnt;
 904                                 $link = $varnt->getText();
 905                                 break;
 906                         }
 907                 }
 908         }
 909
 910         /**
 911          * Returns language specific hash options.
 912          *
 913          * @return string
 914          */
 915         public function getExtraHashOptions() {
 916                 $variant = $this->getPreferredVariant();
 917
 918                 return '!' . $variant;
 919         }
 920
 921         /**
 922          * Guess if a text is written in a variant. This should be implemented in subclasses.
 923          *
 924          * @param string $text The text to be checked
 925          * @param string $variant Language code of the variant to be checked for
 926          * @return bool True if $text appears to be written in $variant, false if not
 927          *
 928          * @author Nikola Smolenski <smolensk@eunet.rs>
 929          * @since 1.19
 930          */
 931         public function guessVariant( $text, $variant ) {
 932                 return false;
 933         }
 934
 935         /**
 936          * Load default conversion tables.
 937          * This method must be implemented in derived class.
 938          *
 939          * @private
 940          * @throws MWException
 941          */
 942         function loadDefaultTables() {
 943                 $class = static::class;
 944                 throw new MWException( "Must implement loadDefaultTables() method in class $class" );
 945         }
 946
 947         /**
 948          * Load conversion tables either from the cache or the disk.
 949          * @private
 950          * @param bool $fromCache Load from memcached? Defaults to true.
 951          */
 952         function loadTables( $fromCache = true ) {
 953                 global $wgLanguageConverterCacheType;
 954
 955                 if ( $this->mTablesLoaded ) {
 956                         return;
 957                 }
 958
 959                 $this->mTablesLoaded = true;
 960                 $this->mTables = null;
 961                 $cache = ObjectCache::getInstance( $wgLanguageConverterCacheType );
 962                 $cacheKey = $cache->makeKey( 'conversiontables', $this->mMainLanguageCode );
 963                 if ( $fromCache ) {
 964                         $this->mTables = $cache->get( $cacheKey );
 965                 }
 966                 if ( !$this->mTables || !array_key_exists( self::CACHE_VERSION_KEY, $this->mTables ) ) {
 967                         // not in cache, or we need a fresh reload.
 968                         // We will first load the default tables
 969                         // then update them using things in MediaWiki:Conversiontable/*
 970                         $this->loadDefaultTables();
 971                         foreach ( $this->mVariants as $var ) {
 972                                 $cached = $this->parseCachedTable( $var );
 973                                 $this->mTables[$var]->mergeArray( $cached );
 974                         }
 975
 976                         $this->postLoadTables();
 977                         $this->mTables[self::CACHE_VERSION_KEY] = true;
 978
 979                         $cache->set( $cacheKey, $this->mTables, 43200 );
 980                 }
 981         }
 982
 983         /**
 984          * Hook for post processing after conversion tables are loaded.
 985          */
 986         function postLoadTables() {
 987         }
 988
 989         /**
 990          * Reload the conversion tables.
 991          *
 992          * Also used by test suites which need to reset the converter state.
 993          *
 994          * @private
 995          */
 996         private function reloadTables() {
 997                 if ( $this->mTables ) {
 998                         // @phan-suppress-next-line PhanTypeObjectUnsetDeclaredProperty
 999                         unset( $this->mTables );
1000                 }
1001
1002                 $this->mTablesLoaded = false;
1003                 $this->loadTables( false );
1004         }
1005
1006         /**
1007          * Parse the conversion table stored in the cache.
1008          *
1009          * The tables should be in blocks of the following form:
1010          *              -{
1011          *                      word => word ;
1012          *                      word => word ;
1013          *                      ...
1014          *              }-
1015          *
1016          * To make the tables more manageable, subpages are allowed
1017          * and will be parsed recursively if $recursive == true.
1018          *
1019          * @param string $code Language code
1020          * @param string $subpage Subpage name
1021          * @param bool $recursive Parse subpages recursively? Defaults to true.
1022          *
1023          * @return array
1024          */
1025         function parseCachedTable( $code, $subpage = '', $recursive = true ) {
1026                 static $parsed = [];
1027
1028                 $key = 'Conversiontable/' . $code;
1029                 if ( $subpage ) {
1030                         $key .= '/' . $subpage;
1031                 }
1032                 if ( array_key_exists( $key, $parsed ) ) {
1033                         return [];
1034                 }
1035
1036                 $parsed[$key] = true;
1037
1038                 if ( $subpage === '' ) {
1039                         $txt = MessageCache::singleton()->getMsgFromNamespace( $key, $code );
1040                 } else {
1041                         $txt = false;
1042                         $title = Title::makeTitleSafe( NS_MEDIAWIKI, $key );
1043                         if ( $title && $title->exists() ) {
1044                                 $revision = Revision::newFromTitle( $title );
1045                                 if ( $revision ) {
1046                                         if ( $revision->getContentModel() == CONTENT_MODEL_WIKITEXT ) {
1047                                                 // @phan-suppress-next-line PhanUndeclaredMethod
1048                                                 $txt = $revision->getContent( RevisionRecord::RAW )->getText();
1049                                         }
1050
1051                                         // @todo in the future, use a specialized content model, perhaps based on json!
1052                                 }
1053                         }
1054                 }
1055
1056                 # Nothing to parse if there's no text
1057                 if ( $txt === false || $txt === null || $txt === '' ) {
1058                         return [];
1059                 }
1060
1061                 // get all subpage links of the form
1062                 // [[MediaWiki:Conversiontable/zh-xx/...|...]]
1063                 $linkhead = $this->mLangObj->getNsText( NS_MEDIAWIKI ) .
1064                         ':Conversiontable';
1065                 $subs = StringUtils::explode( '[[', $txt );
1066                 $sublinks = [];
1067                 foreach ( $subs as $sub ) {
1068                         $link = explode( ']]', $sub, 2 );
1069                         if ( count( $link ) != 2 ) {
1070                                 continue;
1071                         }
1072                         $b = explode( '|', $link[0], 2 );
1073                         $b = explode( '/', trim( $b[0] ), 3 );
1074                         if ( count( $b ) == 3 ) {
1075                                 $sublink = $b[2];
1076                         } else {
1077                                 $sublink = '';
1078                         }
1079
1080                         if ( $b[0] == $linkhead && $b[1] == $code ) {
1081                                 $sublinks[] = $sublink;
1082                         }
1083                 }
1084
1085                 // parse the mappings in this page
1086                 $blocks = StringUtils::explode( '-{', $txt );
1087                 $ret = [];
1088                 $first = true;
1089                 foreach ( $blocks as $block ) {
1090                         if ( $first ) {
1091                                 // Skip the part before the first -{
1092                                 $first = false;
1093                                 continue;
1094                         }
1095                         $mappings = explode( '}-', $block, 2 )[0];
1096                         $stripped = str_replace( [ "'", '"', '*', '#' ], '', $mappings );
1097                         $table = StringUtils::explode( ';', $stripped );
1098                         foreach ( $table as $t ) {
1099                                 $m = explode( '=>', $t, 3 );
1100                                 if ( count( $m ) != 2 ) {
1101                                         continue;
1102                                 }
1103                                 // trim any trailling comments starting with '//'
1104                                 $tt = explode( '//', $m[1], 2 );
1105                                 $ret[trim( $m[0] )] = trim( $tt[0] );
1106                         }
1107                 }
1108
1109                 // recursively parse the subpages
1110                 if ( $recursive ) {
1111                         foreach ( $sublinks as $link ) {
1112                                 $s = $this->parseCachedTable( $code, $link, $recursive );
1113                                 $ret = $s + $ret;
1114                         }
1115                 }
1116
1117                 if ( $this->mUcfirst ) {
1118                         foreach ( $ret as $k => $v ) {
1119                                 $ret[$this->mLangObj->ucfirst( $k )] = $this->mLangObj->ucfirst( $v );
1120                         }
1121                 }
1122                 return $ret;
1123         }
1124
1125         /**
1126          * Enclose a string with the "no conversion" tag. This is used by
1127          * various functions in the Parser.
1128          *
1129          * @param string $text Text to be tagged for no conversion
1130          * @param bool $noParse Unused
1131          * @return string The tagged text
1132          */
1133         public function markNoConversion( $text, $noParse = false ) {
1134                 # don't mark if already marked
1135                 if ( strpos( $text, '-{' ) || strpos( $text, '}-' ) ) {
1136                         return $text;
1137                 }
1138
1139                 $ret = "-{R|$text}-";
1140                 return $ret;
1141         }
1142
1143         /**
1144          * Convert the sorting key for category links. This should make different
1145          * keys that are variants of each other map to the same key.
1146          *
1147          * @param string $key
1148          *
1149          * @return string
1150          */
1151         function convertCategoryKey( $key ) {
1152                 return $key;
1153         }
1154
1155         /**
1156          * Refresh the cache of conversion tables when
1157          * MediaWiki:Conversiontable* is updated.
1158          *
1159          * @param Title $titleobj The Title of the page being updated
1160          */
1161         public function updateConversionTable( Title $titleobj ) {
1162                 if ( $titleobj->getNamespace() == NS_MEDIAWIKI ) {
1163                         $title = $titleobj->getDBkey();
1164                         $t = explode( '/', $title, 3 );
1165                         $c = count( $t );
1166                         if ( $c > 1 && $t[0] == 'Conversiontable' ) {
1167                                 if ( $this->validateVariant( $t[1] ) ) {
1168                                         $this->reloadTables();
1169                                 }
1170                         }
1171                 }
1172         }
1173
1174         /**
1175          * Get the cached separator pattern for ConverterRule::parseRules()
1176          * @return string
1177          */
1178         function getVarSeparatorPattern() {
1179                 if ( is_null( $this->mVarSeparatorPattern ) ) {
1180                         // varsep_pattern for preg_split:
1181                         // text should be splited by ";" only if a valid variant
1182                         // name exist after the markup, for example:
1183                         //  -{zh-hans:<span style="font-size:120%;">xxx</span>;zh-hant:\
1184                         //  <span style="font-size:120%;">yyy</span>;}-
1185                         // we should split it as:
1186                         //  [
1187                         //    [0] => 'zh-hans:<span style="font-size:120%;">xxx</span>'
1188                         //    [1] => 'zh-hant:<span style="font-size:120%;">yyy</span>'
1189                         //    [2] => ''
1190                         //  ]
1191                         $expandedVariants = [];
1192                         foreach ( $this->mVariants as $variant ) {
1193                                 $expandedVariants[ $variant ] = 1;
1194                                 // Accept standard BCP 47 names for variants as well.
1195                                 $expandedVariants[ LanguageCode::bcp47( $variant ) ] = 1;
1196                         }
1197                         // Accept old deprecated names for variants
1198                         foreach ( LanguageCode::getDeprecatedCodeMapping() as $old => $new ) {
1199                                 if ( isset( $expandedVariants[ $new ] ) ) {
1200                                         $expandedVariants[ $old ] = 1;
1201                                 }
1202                         }
1203
1204                         $pat = '/;\s*(?=';
1205                         foreach ( $expandedVariants as $variant => $ignore ) {
1206                                 // zh-hans:xxx;zh-hant:yyy
1207                                 $pat .= $variant . '\s*:|';
1208                                 // xxx=>zh-hans:yyy; xxx=>zh-hant:zzz
1209                                 $pat .= '[^;]*?=>\s*' . $variant . '\s*:|';
1210                         }
1211                         $pat .= '\s*$)/';
1212                         $this->mVarSeparatorPattern = $pat;
1213                 }
1214                 return $this->mVarSeparatorPattern;
1215         }
1216 }