refactor: Change checking of unscoping permissions

Instead of checking the page content for a raw `wrapclass` string, look up the current revision's user and check if that user has the permission to enable un-scoping.

This _is_ expensive as each time the tag is handled, a lookup will occur.

In reference to #18

README.md

@@ -33,6 +33,8 @@ Enables or disables css variable support.
 Default: `false`  
 Allows users with `editinterface` permissions to unscope css by setting a `wrapclass` attribute.
 
+**Note**: This is potentially expensive, as each templatestyles tag with `wrapclass` set, will attempt to look up the user of the current page revision, and check if this user has the permission to activate css un-scoping. 
+
 Example:
 `<templatestyles src="Foo/style.css" wrapclass="mediawiki" />` results in the css being scoped to `.mediawiki` instead of `.mw-parser-output`.
 

extension.json

@@ -48,18 +48,13 @@
 	},
 	"HookHandlers": {
 		"MainHooks": {
-			"class": "MediaWiki\\Extension\\TemplateStylesExtender\\Hooks\\MainHooks",
-			"services": [
-				"PermissionManager",
-				"UserFactory"
-			]
+			"class": "MediaWiki\\Extension\\TemplateStylesExtender\\Hooks\\MainHooks"
 		}
 	},
 	"Hooks": {
 		"TemplateStylesPropertySanitizer": "MediaWiki\\Extension\\TemplateStylesExtender\\Hooks\\PropertySanitizerHook::onSanitize",
 		"TemplateStylesStylesheetSanitizer": "MediaWiki\\Extension\\TemplateStylesExtender\\Hooks\\StylesheetSanitizerHook::onSanitize",
-		"ParserFirstCallInit": "MainHooks",
-		"EditPage::attemptSave": "MainHooks"
+		"ParserFirstCallInit": "MainHooks"
 	},
 	"manifest_version": 2
 }

includes/Hooks/MainHooks.php

@@ -2,42 +2,19 @@
 
 namespace MediaWiki\Extension\TemplateStylesExtender\Hooks;
 
-use MediaWiki\EditPage\EditPage;
 use MediaWiki\Extension\TemplateStyles\Hooks;
 use MediaWiki\Extension\TemplateStylesExtender\TemplateStylesExtender;
-use MediaWiki\Hook\EditPage__attemptSaveHook;
 use MediaWiki\Hook\ParserFirstCallInitHook;
-use MediaWiki\Permissions\PermissionManager;
-use MediaWiki\Revision\SlotRecord;
-use MediaWiki\User\UserFactory;
+use MediaWiki\MediaWikiServices;
+use MediaWiki\User\UserIdentity;
 use MWException;
 use Parser;
-use PermissionsError;
 use PPFrame;
 
 /**
  * phpcs:disable MediaWiki.NamingConventions.LowerCamelFunctionsName.FunctionName
  */
-class MainHooks implements ParserFirstCallInitHook, EditPage__attemptSaveHook {
-
-	/**
-	 * @var PermissionManager
-	 */
-	private PermissionManager $manager;
-
-	/**
-	 * @var UserFactory
-	 */
-	private UserFactory $factory;
-
-	/**
-	 * @param PermissionManager $manager
-	 * @param UserFactory $factory
-	 */
-	public function __construct( PermissionManager $manager, UserFactory $factory ) {
-		$this->manager = $manager;
-		$this->factory = $factory;
-	}
+class MainHooks implements ParserFirstCallInitHook {
 
 	/**
 	 * @param Parser $parser
@@ -51,6 +28,9 @@ class MainHooks implements ParserFirstCallInitHook, EditPage__attemptSaveHook {
 	 * This is a wrapper for <templatestyles> tags,
 	 * that allows unscoping of css for users with 'editinterface' permissions
 	 *
+	 * Note this is a potentially expensive operation, as a lookup for the user of the current revision is done.
+	 * The unscoping will only happen, if the editor of the current revision has the rights to do so
+	 *
 	 * @param string $text
 	 * @param string[] $params
 	 * @param Parser $parser
@@ -59,17 +39,40 @@ class MainHooks implements ParserFirstCallInitHook, EditPage__attemptSaveHook {
 	 * @see Hooks::handleTag()
 	 */
 	public static function handleTag( $text, $params, $parser, $frame ): string {
+		$getOutput = static fn() => Hooks::handleTag( $text, $params, $parser, $frame );
+
 		if (
+			!isset( $params['wrapclass'] ) ||
 			$parser->getOptions() === null ||
 			!TemplateStylesExtender::getConfigValue( 'TemplateStylesExtenderEnableUnscopingSupport' )
 		) {
-			return Hooks::handleTag( $text, $params, $parser, $frame );
+			return $getOutput();
 		}
 
+		// 'wrapclass' option is set...
+
+		/** @var \ParserOptions $options - Fix typehint */
 		$options = $parser->getOptions();
 		$wrapClass = $options->getWrapOutputClass();
 
-		if ( isset( $params['wrapclass'] ) ) {
+		$permission = TemplateStylesExtender::getConfigValue( 'TemplateStylesExtenderUnscopingPermission' );
+
+		$rev = MediaWikiServices::getInstance()->getRevisionLookup()->getRevisionByTitle( $frame->getTitle() );
+
+		if ( $rev === null || $rev->getUser() === null ) {
+			return $getOutput();
+		}
+
+		/** @var UserIdentity $user - Fix typehint */
+		$user = $rev->getUser();
+		$user = MediaWikiServices::getInstance()->getUserFactory()->newFromUserIdentity( $user );
+		$permissionManager = MediaWikiServices::getInstance()->getPermissionManager();
+
+		$userCan = $permissionManager->userHasRight( $user, $permission )
+			|| $permissionManager->userCan( $permission, $user, $frame->getTitle() );
+
+		// If the editor of the last revision is allowed to change the wrapclass, set it
+		if ( $userCan ) {
 			$options->setOption( 'wrapclass', $params['wrapclass'] );
 		}
 
@@ -78,40 +81,4 @@ class MainHooks implements ParserFirstCallInitHook, EditPage__attemptSaveHook {
 
 		return $out;
 	}
-
-	/**
-	 * Check if 'wrapclass' was used in the page, if so only users with 'editinterface' permissions may save the page
-	 *
-	 * @param EditPage $editpage_Obj
-	 * @return true
-	 * @throws PermissionsError
-	 */
-	public function onEditPage__attemptSave( $editpage_Obj ): bool {
-		$revision = $editpage_Obj->getExpectedParentRevision();
-
-		if (
-			$revision === null ||
-			!TemplateStylesExtender::getConfigValue( 'TemplateStylesExtenderEnableUnscopingSupport' )
-		) {
-			return true;
-		}
-
-		$content = $revision->getContent( SlotRecord::MAIN );
-		if ( $content === null ) {
-			return true;
-		}
-
-		$permission = TemplateStylesExtender::getConfigValue( 'TemplateStylesExtenderUnscopingPermission' );
-
-		$user = $this->factory->newFromUserIdentity( $editpage_Obj->getContext()->getUser() );
-
-		$userCan = $this->manager->userHasRight( $user, $permission ) ||
-			$this->manager->userCan( $permission, $user, $editpage_Obj->getTitle() );
-
-		if ( strpos( $content->getText(), 'wrapclass' ) !== false && !$userCan ) {
-			throw new PermissionsError( $permission, [ 'templatestylesextender-unscope-no-permisson' ] );
-		}
-
-		return true;
-	}
 }