wcfsetup/install/files/lib/system/style/StyleCompiler.class.php

   1 <?php
   2
   3 namespace wcf\system\style;
   4
   5 use ScssPhp\ScssPhp\Compiler;
   6 use ScssPhp\ScssPhp\OutputStyle;
   7 use wcf\data\application\Application;
   8 use wcf\data\option\Option;
   9 use wcf\data\style\Style;
  10 use wcf\system\application\ApplicationHandler;
  11 use wcf\system\event\EventHandler;
  12 use wcf\system\exception\SystemException;
  13 use wcf\system\SingletonFactory;
  14 use wcf\system\WCF;
  15 use wcf\util\FileUtil;
  16 use wcf\util\JSON;
  17 use wcf\util\StringUtil;
  18 use wcf\util\StyleUtil;
  19 use wcf\util\Url;
  20
  21 /**
  22  * Provides access to the SCSS PHP compiler.
  23  *
  24  * @author  Tim Duesterhus, Alexander Ebert
  25  * @copyright   2001-2021 WoltLab GmbH
  26  * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
  27  * @package WoltLabSuite\Core\System\Style
  28  */
  29 final class StyleCompiler extends SingletonFactory
  30 {
  31     /**
  32      * Contains all files, which are compiled for a style.
  33      * @var string[]
  34      */
  35     protected $files;
  36
  37     /**
  38      * names of option types which are supported as additional variables
  39      * @var string[]
  40      */
  41     public static $supportedOptionType = ['boolean', 'float', 'integer', 'radioButton', 'select'];
  42
  43     /**
  44      * file used to store global SCSS declarations, relative to `WCF_DIR`
  45      * @var string
  46      */
  47     const FILE_GLOBAL_VALUES = 'style/ui/zzz_wsc_style_global_values.scss';
  48
  49     /**
  50      * registry keys for data storage
  51      * @var string
  52      */
  53     const REGISTRY_GLOBAL_VALUES = 'styleGlobalValues';
  54
  55     public const SYSTEM_FONT_NAME = 'system';
  56
  57     private const SYSTEM_FONT_FAMILY = 'system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
  58         "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans",
  59         "Helvetica Neue", Arial, sans-serif';
  60
  61     private const SYSTEM_FONT_FAMILY_MONOSPACE = 'ui-monospace, Menlo, Monaco, "Cascadia Mono",
  62         "Segoe UI Mono", "Roboto Mono", "Oxygen Mono", "Ubuntu Monospace", "Source Code Pro",
  63         "Fira Mono", "Droid Sans Mono", "Courier New", monospace';
  64
  65     /**
  66      * @inheritDoc
  67      */
  68     protected function init()
  69     {
  70         require_once(WCF_DIR . 'lib/system/style/scssphp/scss.inc.php');
  71     }
  72
  73     /**
  74      * Returns a fresh instance of the scssphp compiler.
  75      */
  76     protected function makeCompiler(): Compiler
  77     {
  78         $compiler = new Compiler();
  79         // Disable Unicode support because of its horrible performance (7x slowdown)
  80         // https://github.com/WoltLab/WCF/pull/2736#issuecomment-416084079
  81         $compiler->setEncoding('iso8859-1');
  82         $compiler->setImportPaths([WCF_DIR]);
  83
  84         if (\ENABLE_DEBUG_MODE && \ENABLE_DEVELOPER_TOOLS) {
  85             $compiler->setOutputStyle(OutputStyle::EXPANDED);
  86         } else {
  87             $compiler->setOutputStyle(OutputStyle::COMPRESSED);
  88         }
  89
  90         return $compiler;
  91     }
  92
  93     /**
  94      * Returns the default style variables as array.
  95      *
  96      * @return      string[]
  97      * @since       5.3
  98      */
  99     public static function getDefaultVariables()
 100     {
 101         $variables = [];
 102
 103         $sql = "SELECT      variable.variableName, variable.defaultValue
 104                 FROM        wcf" . WCF_N . "_style_variable variable
 105                 ORDER BY    variable.variableID ASC";
 106         $statement = WCF::getDB()->prepareStatement($sql);
 107         $statement->execute();
 108         $variables = $statement->fetchMap('variableName', 'defaultValue');
 109
 110         // see https://github.com/WoltLab/WCF/issues/2636
 111         if (empty($variables['wcfPageThemeColor'])) {
 112             $variables['wcfPageThemeColor'] = $variables['wcfHeaderBackground'];
 113         }
 114
 115         return $variables;
 116     }
 117
 118     /**
 119      * Test a style with the given apiVersion, imagePath and variables. If the style is valid and does not throw an
 120      * error, null is returned. Otherwise the exception is returned (!).
 121      *
 122      * @param string $testFileDir
 123      * @param string $styleName
 124      * @param string $apiVersion
 125      * @param string $imagePath
 126      * @param string[] $variables
 127      * @param string|null $customCustomSCSSFile
 128      * @return      null|\Exception
 129      * @since       5.3
 130      */
 131     public function testStyle(
 132         $testFileDir,
 133         $styleName,
 134         $apiVersion,
 135         $imagePath,
 136         array $variables,
 137         $customCustomSCSSFile = null
 138     ) {
 139         $individualScss = '';
 140         if (isset($variables['individualScss'])) {
 141             $individualScss = $variables['individualScss'];
 142             unset($variables['individualScss']);
 143         }
 144
 145         // add style image path
 146         if ($imagePath) {
 147             $imagePath = FileUtil::getRelativePath(WCF_DIR . 'style/', WCF_DIR . $imagePath);
 148             $imagePath = FileUtil::addTrailingSlash(FileUtil::unifyDirSeparator($imagePath));
 149         } else {
 150             $imagePath = '../images/';
 151         }
 152         $variables['style_image_path'] = "'{$imagePath}'";
 153
 154         // apply overrides
 155         if (isset($variables['overrideScss'])) {
 156             $lines = \explode("\n", StringUtil::unifyNewlines($variables['overrideScss']));
 157             foreach ($lines as $line) {
 158                 if (\preg_match('~^@([a-zA-Z]+): ?([@a-zA-Z0-9 ,\.\(\)\%\#-]+);$~', $line, $matches)) {
 159                     $variables[$matches[1]] = $matches[2];
 160                 }
 161             }
 162             unset($variables['overrideScss']);
 163         }
 164
 165         // api version
 166         $variables['apiVersion'] = $apiVersion;
 167
 168         $parameters = ['scss' => ''];
 169         EventHandler::getInstance()->fireAction($this, 'compile', $parameters);
 170
 171         $files = $this->getFiles();
 172
 173         if ($customCustomSCSSFile !== null) {
 174             if (($customSCSSFileKey = \array_search(WCF_DIR . self::FILE_GLOBAL_VALUES, $files)) !== false) {
 175                 unset($files[$customSCSSFileKey]);
 176             }
 177
 178             $files[] = $customCustomSCSSFile;
 179         }
 180
 181         $scss = "/*!\n\nstylesheet for '" . $styleName . "', generated on " . \gmdate('r') . " -- DO NOT EDIT\n\n*/\n";
 182         $scss .= $this->bootstrap($variables);
 183         foreach ($files as $file) {
 184             $scss .= $this->prepareFile($file);
 185         }
 186         $scss .= $individualScss;
 187         if (!empty($parameters['scss'])) {
 188             $scss .= "\n" . $parameters['scss'];
 189         }
 190
 191         try {
 192             $css = $this->compileStylesheet(
 193                 $scss,
 194                 $variables
 195             );
 196
 197             $this->writeCss(FileUtil::addTrailingSlash($testFileDir) . 'style', $css);
 198         } catch (\Exception $e) {
 199             return $e;
 200         }
 201
 202         return null;
 203     }
 204
 205     /**
 206      * Returns a array with all files, which should be compiled for a style.
 207      *
 208      * @return      string[]
 209      * @since       5.3
 210      */
 211     protected function getFiles()
 212     {
 213         if (!$this->files) {
 214             $files = $this->getCoreFiles();
 215
 216             // read stylesheets in dependency order
 217             $sql = "SELECT      filename, application
 218                     FROM        wcf" . WCF_N . "_package_installation_file_log
 219                     WHERE       CONVERT(filename using utf8) REGEXP ?
 220                             AND packageID <> ?
 221                     ORDER BY    packageID";
 222             $statement = WCF::getDB()->prepareStatement($sql);
 223             $statement->execute([
 224                 'style/([a-zA-Z0-9\-\.]+)\.scss',
 225                 1,
 226             ]);
 227             while ($row = $statement->fetchArray()) {
 228                 // the global values will always be evaluated last
 229                 if ($row['filename'] === self::FILE_GLOBAL_VALUES) {
 230                     continue;
 231                 }
 232
 233                 $files[] = Application::getDirectory($row['application']) . $row['filename'];
 234             }
 235
 236             // global SCSS
 237             if (\file_exists(WCF_DIR . self::FILE_GLOBAL_VALUES)) {
 238                 $files[] = WCF_DIR . self::FILE_GLOBAL_VALUES;
 239             }
 240
 241             $this->files = $files;
 242         }
 243
 244         return $this->files;
 245     }
 246
 247     /**
 248      * Compiles SCSS stylesheets.
 249      *
 250      * @param Style $style
 251      */
 252     public function compile(Style $style)
 253     {
 254         // get style variables
 255         $variables = $style->getVariables();
 256         $individualScss = '';
 257         if (isset($variables['individualScss'])) {
 258             $individualScss = $variables['individualScss'];
 259             unset($variables['individualScss']);
 260         }
 261
 262         // add style image path
 263         $imagePath = '../images/';
 264         if ($style->imagePath) {
 265             $imagePath = FileUtil::getRelativePath(WCF_DIR . 'style/', WCF_DIR . $style->imagePath);
 266             $imagePath = FileUtil::addTrailingSlash(FileUtil::unifyDirSeparator($imagePath));
 267         }
 268         $variables['style_image_path'] = "'{$imagePath}'";
 269
 270         // apply overrides
 271         if (isset($variables['overrideScss'])) {
 272             $lines = \explode("\n", StringUtil::unifyNewlines($variables['overrideScss']));
 273             foreach ($lines as $line) {
 274                 if (\preg_match('~^@([a-zA-Z]+): ?([@a-zA-Z0-9 ,\.\(\)\%\#-]+);$~', $line, $matches)) {
 275                     $variables[$matches[1]] = $matches[2];
 276                 }
 277             }
 278             unset($variables['overrideScss']);
 279         }
 280
 281         // api version
 282         $variables['apiVersion'] = $style->apiVersion;
 283
 284         $parameters = ['scss' => ''];
 285         EventHandler::getInstance()->fireAction($this, 'compile', $parameters);
 286
 287         $scss = "/*!\n\nstylesheet for '" . $style->styleName . "', generated on " . \gmdate('r') . " -- DO NOT EDIT\n\n*/\n";
 288         $scss .= $this->bootstrap($variables);
 289         foreach ($this->getFiles() as $file) {
 290             $scss .= $this->prepareFile($file);
 291         }
 292         $scss .= $individualScss;
 293         if (!empty($parameters['scss'])) {
 294             $scss .= "\n" . $parameters['scss'];
 295         }
 296
 297         $css = $this->compileStylesheet(
 298             $scss,
 299             $variables
 300         );
 301
 302         $preloadManifest = $this->buildPreloadManifest(
 303             $this->extractPreloadRequests($css)
 304         );
 305
 306         $this->writeCss($this->getFilenameForStyle($style), $css, $preloadManifest);
 307     }
 308
 309     /**
 310      * Builds the preload manifest from the given iterable containing
 311      * preload requests.
 312      *
 313      * @see StyleCompiler::extractPreloadRequests()
 314      * @since 5.4
 315      */
 316     private function buildPreloadManifest(iterable $requests): array
 317     {
 318         $preloadManifest = ['http' => [], 'html' => []];
 319
 320         foreach ($requests as $request) {
 321             if (Url::is($request['filename'])) {
 322                 $filename = $request['filename'];
 323             } else {
 324                 $filename = WCF::getPath() . FileUtil::getRealPath('style/' . $request['filename']);
 325             }
 326
 327             $http = "<{$filename}>; rel=preload; as={$request['as']}";
 328             $html = \sprintf(
 329                 '<link rel="preload" href="%s" as="%s"',
 330                 StringUtil::encodeHTML($filename),
 331                 StringUtil::encodeHTML($request['as'])
 332             );
 333             if ($request['crossorigin']) {
 334                 $http .= "; crossorigin";
 335                 $html .= " crossorigin";
 336             }
 337             if ($request['type']) {
 338                 $http .= \sprintf('; type="%s"', \addslashes($request['type']));
 339                 $html .= \sprintf(' type="%s"', StringUtil::encodeHTML($request['type']));
 340             }
 341             $html .= '>';
 342             $preloadManifest['http'][] = $http;
 343             $preloadManifest['html'][] = $html;
 344         }
 345
 346         return $preloadManifest;
 347     }
 348
 349     /**
 350      * Extracts preload requests from the given CSS string.
 351      *
 352      * @since 5.4
 353      */
 354     private function extractPreloadRequests(string $css): iterable
 355     {
 356         $regex = '/--woltlab-suite-preload:\\s*preload_dummy\\(((?:"(?:\\\\.|[^\\\\"])*"|[^")])+)\\)\\s*[;\\}]/';
 357         if (!\preg_match_all($regex, $css, $requests)) {
 358             return [];
 359         }
 360
 361         foreach ($requests[1] as $request) {
 362             $regex = '/\s*("(?:\\\\.|[^\\\\"])*"|[^",]+)\s*(?:,|$)\s*/';
 363             if (!\preg_match_all($regex, $request, $parameters)) {
 364                 continue;
 365             }
 366             $parameters = $parameters[1];
 367             if (\count($parameters) < 4) {
 368                 continue;
 369             }
 370             $parameters = \array_map(static function (string $parameter) {
 371                 if ($parameter[0] === '"') {
 372                     return \stripslashes(\substr($parameter, 1, -1));
 373                 }
 374
 375                 return $parameter;
 376             }, $parameters);
 377             [$filename, $as, $crossorigin, $type] = $parameters;
 378
 379             yield [
 380                 'filename' => $filename,
 381                 'as' => $as,
 382                 'crossorigin' => !!$crossorigin,
 383                 'type' => $type ?: null,
 384             ];
 385         }
 386     }
 387
 388     /**
 389      * Compiles SCSS stylesheets for ACP usage.
 390      */
 391     public function compileACP()
 392     {
 393         $files = $this->getCoreFiles();
 394
 395         // ACP uses a slightly different layout
 396         $files[] = WCF_DIR . 'acp/style/layout.scss';
 397
 398         // include stylesheets from other apps in arbitrary order
 399         if (PACKAGE_ID) {
 400             foreach (ApplicationHandler::getInstance()->getApplications() as $application) {
 401                 $files = \array_merge($files, $this->getAcpStylesheets($application));
 402             }
 403         }
 404
 405         // read default values
 406         $sql = "SELECT      variableName, defaultValue
 407                 FROM        wcf" . WCF_N . "_style_variable
 408                 ORDER BY    variableID ASC";
 409         $statement = WCF::getDB()->prepareStatement($sql);
 410         $statement->execute();
 411         $variables = [];
 412         while ($row = $statement->fetchArray()) {
 413             $value = $row['defaultValue'];
 414             if (empty($value)) {
 415                 $value = '~""';
 416             }
 417
 418             $variables[$row['variableName']] = $value;
 419         }
 420
 421         $variables['style_image_path'] = "'../images/'";
 422
 423         $scss = "/*!\n\nstylesheet for the admin panel, generated on " . \gmdate('r') . " -- DO NOT EDIT\n\n*/\n";
 424         $scss .= $this->bootstrap($variables);
 425         foreach ($files as $file) {
 426             $scss .= $this->prepareFile($file);
 427         }
 428
 429         $css = $this->compileStylesheet(
 430             $scss,
 431             $variables
 432         );
 433
 434         // fix relative paths
 435         $css = \str_replace('../font/', '../../font/', $css);
 436         $css = \str_replace('../icon/', '../../icon/', $css);
 437         $css = \preg_replace('~\.\./images/~', '../../images/', $css);
 438
 439         $this->writeCss(WCF_DIR . 'acp/style/style', $css);
 440     }
 441
 442     /**
 443      * Returns a list of common stylesheets provided by the core.
 444      *
 445      * @return      string[]        list of common stylesheets
 446      */
 447     protected function getCoreFiles()
 448     {
 449         $files = [];
 450         if ($handle = \opendir(WCF_DIR . 'style/')) {
 451             while (($file = \readdir($handle)) !== false) {
 452                 if ($file === '.' || $file === '..' || $file === 'bootstrap' || \is_file(WCF_DIR . 'style/' . $file)) {
 453                     continue;
 454                 }
 455
 456                 $file = WCF_DIR . "style/{$file}/";
 457                 if ($innerHandle = \opendir($file)) {
 458                     while (($innerFile = \readdir($innerHandle)) !== false) {
 459                         if (
 460                             $innerFile === '.'
 461                             || $innerFile === '..'
 462                             || !\is_file($file . $innerFile)
 463                             || !\preg_match('~^[a-zA-Z0-9\-\.]+\.scss$~', $innerFile)
 464                         ) {
 465                             continue;
 466                         }
 467
 468                         $files[] = $file . $innerFile;
 469                     }
 470                     \closedir($innerHandle);
 471                 }
 472             }
 473
 474             \closedir($handle);
 475
 476             // directory order is not deterministic in some cases
 477             \sort($files);
 478         }
 479
 480         return $files;
 481     }
 482
 483     /**
 484      * Returns the list of SCSS stylesheets of an application.
 485      *
 486      * @param Application $application
 487      * @return      string[]
 488      */
 489     protected function getAcpStylesheets(Application $application)
 490     {
 491         if ($application->packageID == 1) {
 492             return [];
 493         }
 494
 495         $files = [];
 496
 497         $basePath = FileUtil::addTrailingSlash(FileUtil::getRealPath(WCF_DIR . $application->getPackage()->packageDir)) . 'acp/style/';
 498         $result = \glob($basePath . '*.scss');
 499         if (\is_array($result)) {
 500             foreach ($result as $file) {
 501                 $files[] = $file;
 502             }
 503         }
 504
 505         return $files;
 506     }
 507
 508     /**
 509      * Reads in the SCSS files that form the foundation of the stylesheet. This includes
 510      * the CSS reset and mixins.
 511      */
 512     protected function bootstrap(array $variables): string
 513     {
 514         // add reset like a boss
 515         $content = $this->prepareFile(WCF_DIR . 'style/bootstrap/reset.scss');
 516
 517         // add mixins
 518         $content .= $this->prepareFile(WCF_DIR . 'style/bootstrap/mixin.scss');
 519
 520         // add newer mixins added with version 3.0
 521         foreach (\glob(WCF_DIR . 'style/bootstrap/mixin/*.scss') as $mixin) {
 522             $content .= $this->prepareFile($mixin);
 523         }
 524
 525         $content .= <<<'EOT'
 526             @function preload($filename, $as, $crossorigin: false, $type: "") {
 527                 @if $crossorigin {
 528                     @return preload_dummy($filename, $as, 1, $type);
 529                 } @else {
 530                     @return preload_dummy($filename, $as, 0, $type);
 531                 }
 532             }
 533 EOT;
 534
 535         if (ApplicationHandler::getInstance()->isMultiDomainSetup()) {
 536             $content .= <<<'EOT'
 537                 @function getFont($filename, $family: "/", $version: "") {
 538                     @return "../font/getFont.php?family=" + $family + "&filename=" + $filename + "&v=" + $version;
 539                 }
 540 EOT;
 541         } else {
 542             $content .= <<<'EOT'
 543                 @function getFont($filename, $family: "/", $version: "") {
 544                     @if ($family != "") {
 545                         $family: "families/" + $family + "/";
 546                     }
 547                     @if ($version != "") {
 548                         $version: "?v=" + $version;
 549                     }
 550
 551                     @return "../font/" + $family + $filename + $version;
 552                 }
 553 EOT;
 554         }
 555
 556         if (!empty($variables['wcfFontFamilyGoogle'])) {
 557             $content .= $this->getGoogleFontScss($variables['wcfFontFamilyGoogle']);
 558         }
 559
 560         return $content;
 561     }
 562
 563     /**
 564      * Prepares a SCSS stylesheet for importing.
 565      *
 566      * @param string $filename
 567      * @return  string
 568      * @throws  SystemException
 569      */
 570     protected function prepareFile($filename)
 571     {
 572         if (!\file_exists($filename) || !\is_readable($filename)) {
 573             throw new SystemException("Unable to access '" . $filename . "', does not exist or is not readable");
 574         }
 575
 576         // use a relative path
 577         $filename = FileUtil::getRelativePath(WCF_DIR, \dirname($filename)) . \basename($filename);
 578
 579         return '@import "' . $filename . '";' . "\n";
 580     }
 581
 582     /**
 583      * Compiles the given SCSS into one CSS stylesheet and returns it.
 584      *
 585      * @param string[] $variables
 586      */
 587     protected function compileStylesheet(string $scss, array $variables): string
 588     {
 589         foreach ($variables as &$value) {
 590             if (StringUtil::startsWith($value, '../')) {
 591                 $value = '~"' . $value . '"';
 592             }
 593         }
 594         unset($value);
 595
 596         $variables['wcfFontFamily'] = $variables['wcfFontFamilyFallback'];
 597         if (!empty($variables['wcfFontFamilyGoogle']) && $variables['wcfFontFamilyGoogle'] !== '~""') {
 598             // The SCSS parser attempts to evaluate the variables, causing issues with font names that
 599             // include logical operators such as "And" or "Or".
 600             $variables['wcfFontFamilyGoogle'] = '"' . $variables['wcfFontFamilyGoogle'] . '"';
 601
 602             $variables['wcfFontFamily'] = $variables['wcfFontFamilyGoogle'] . ', ' . $variables['wcfFontFamily'];
 603         }
 604
 605         // Define the font family set for the OS default fonts. This needs to be happen statically to
 606         // allow modifications in the future in case of changes.
 607         $variables['wcfFontFamilyMonospace'] = self::SYSTEM_FONT_FAMILY_MONOSPACE;
 608
 609         if ($variables['wcfFontFamily'] === self::SYSTEM_FONT_NAME) {
 610             $variables['wcfFontFamily'] = self::SYSTEM_FONT_FAMILY;
 611         }
 612
 613         // add options as SCSS variables
 614         if (PACKAGE_ID) {
 615             foreach (Option::getOptions() as $constantName => $option) {
 616                 if (\in_array($option->optionType, static::$supportedOptionType)) {
 617                     $variables['wcf_option_' . \mb_strtolower($constantName)] = \is_int($option->optionValue) ? $option->optionValue : '"' . $option->optionValue . '"';
 618                 }
 619             }
 620
 621             // api version
 622             if (!isset($variables['apiVersion'])) {
 623                 $variables['apiVersion'] = Style::API_VERSION;
 624             }
 625         } else {
 626             // workaround during setup
 627             $variables['wcf_option_attachment_thumbnail_height'] = '~"210"';
 628             $variables['wcf_option_attachment_thumbnail_width'] = '~"280"';
 629             $variables['wcf_option_signature_max_image_height'] = '~"150"';
 630
 631             $variables['apiVersion'] = Style::API_VERSION;
 632         }
 633
 634         // convert into numeric value for comparison, e.g. `3.1` -> `31`
 635         $variables['apiVersion'] = \str_replace('.', '', $variables['apiVersion']);
 636
 637         $compiler = $this->makeCompiler();
 638         $compiler->setVariables($variables);
 639
 640         try {
 641             return $compiler->compile($scss);
 642         } catch (\Exception $e) {
 643             throw new SystemException("Could not compile SCSS: " . $e->getMessage(), 0, '', $e);
 644         }
 645     }
 646
 647     /**
 648      * Converts the given CSS into the RTL variant.
 649      *
 650      * This method differs from StyleUtil::convertCSSToRTL() in that it includes some fixes
 651      * for elements that need to remain LTR.
 652      *
 653      * @see StyleUtil::convertCSSToRTL()
 654      */
 655     private function convertToRtl(string $css): string
 656     {
 657         $css = StyleUtil::convertCSSToRTL($css);
 658
 659         // force code boxes to be always LTR
 660         $css .= "\n/* RTL fix for code boxes */\n";
 661         $css .= ".redactor-layer pre { direction: ltr; text-align: left; }\n";
 662         $css .= ".codeBoxCode { direction: ltr; } \n";
 663         $css .= ".codeBox .codeBoxCode { padding-left: 7ch; padding-right: 0; } \n";
 664         $css .= ".codeBox .codeBoxCode > code .codeBoxLine > a { margin-left: -7ch; margin-right: 0; text-align: right; } \n";
 665
 666         return $css;
 667     }
 668
 669     /**
 670      * Writes the given css into the file with the given prefix.
 671      */
 672     private function writeCss(string $filePrefix, string $css, ?array $preloadManifest = null): void
 673     {
 674         \file_put_contents($filePrefix . '.css', $css);
 675         FileUtil::makeWritable($filePrefix . '.css');
 676
 677         \file_put_contents($filePrefix . '-rtl.css', $this->convertToRtl($css));
 678         FileUtil::makeWritable($filePrefix . '-rtl.css');
 679
 680         if ($preloadManifest) {
 681             \file_put_contents($filePrefix . '-preload.json', JSON::encode($preloadManifest));
 682             FileUtil::makeWritable($filePrefix . '-preload.json');
 683         }
 684     }
 685
 686     /**
 687      * Returns the SCSS required to load a Google font.
 688      */
 689     private function getGoogleFontScss(string $font): string
 690     {
 691         if (!PACKAGE_ID) {
 692             return '';
 693         }
 694
 695         $cssFile = FontManager::getInstance()->getCssFilename($font);
 696         if (!\is_readable($cssFile)) {
 697             return '';
 698         }
 699
 700         return \file_get_contents($cssFile);
 701     }
 702
 703     /**
 704      * Returns the name of the CSS file for a specific style.
 705      *
 706      * @param Style $style
 707      * @return      string
 708      * @since       5.3
 709      */
 710     public static function getFilenameForStyle(Style $style)
 711     {
 712         return WCF_DIR . 'style/style-' . $style->styleID;
 713     }
 714 }