fixes #4133

Closes #4133

Merge request studip/studip!2978

24 files changed, 45 insertions, 48 deletions

diff --git a/lib/archiv.inc.php b/lib/archiv.inc.php
index 8fe4bc9..e40685f 100644
--- a/lib/archiv.inc.php
+++ b/lib/archiv.inc.php
@@ -64,7 +64,7 @@ function lastActivity ($sem_id)
                           WHERE `range_id` = :id";
         }
 
-        foreach (PluginEngine::getPlugins('ForumModule') as $plugin) {
+        foreach (PluginEngine::getPlugins(ForumModule::class) as $plugin) {
             $table = $plugin->getEntryTableInfo();
             $queries[] = 'SELECT MAX(`'. $table['chdate'] .'`) AS chdate FROM `'. $table['table'] .'` WHERE `'. $table['seminar_id'] .'` = :id';
         }
diff --git a/lib/classes/JsonApi/RouteMap.php b/lib/classes/JsonApi/RouteMap.php
index 4f44165..d81bbbf 100644
--- a/lib/classes/JsonApi/RouteMap.php
+++ b/lib/classes/JsonApi/RouteMap.php
@@ -122,7 +122,7 @@ class RouteMap
         $this->addAuthenticatedContactsRoutes($group);
         $this->addAuthenticatedCoursesRoutes($group);
 
-        if (\PluginManager::getInstance()->getPlugin('CoursewareModule')) {
+        if (\PluginManager::getInstance()->getPlugin(\CoursewareModule::class)) {
             $this->addAuthenticatedCoursewareRoutes($group);
         }
 
@@ -155,7 +155,7 @@ class RouteMap
 
         $group->get('/studip/properties', Routes\Studip\PropertiesIndex::class);
 
-        if (\PluginManager::getInstance()->getPlugin('CoursewareModule')) {
+        if (\PluginManager::getInstance()->getPlugin(\CoursewareModule::class)) {
             $group->get('/public/courseware/{link_id}/courseware-structural-elements/{id}', Routes\Courseware\PublicStructuralElementsShow::class);
             $group->get('/public/courseware/{link_id}/courseware-structural-elements', Routes\Courseware\PublicStructuralElementsIndex::class);
         }
diff --git a/lib/classes/Metrics.php b/lib/classes/Metrics.php
index c3874d5..e6a2925 100644
--- a/lib/classes/Metrics.php
+++ b/lib/classes/Metrics.php
@@ -191,7 +191,7 @@ class Metrics {
 
         // cache the activated MetricsPlugins
         if (!self::$metricPlugins) {
-            self::$metricPlugins = \PluginEngine::getPlugins('MetricsPlugin');
+            self::$metricPlugins = \PluginEngine::getPlugins(MetricsPlugin::class);
         }
 
         // call every MetricPlugin
diff --git a/lib/classes/MyRealmModel.php b/lib/classes/MyRealmModel.php
index ab9aa20..8997e78 100644
--- a/lib/classes/MyRealmModel.php
+++ b/lib/classes/MyRealmModel.php
@@ -475,7 +475,7 @@ class MyRealmModel
     public static function setObjectVisits($object, $user_id, $timestamp = null)
     {
         // load plugins, so they have a chance to register themselves as observers
-        PluginEngine::getPlugins('StandardPlugin');
+        PluginEngine::getPlugins(StandardPlugin::class);
 
         // Update news and votes
         $query = "INSERT INTO object_user_visits
diff --git a/lib/classes/Privacy.php b/lib/classes/Privacy.php
index 0ba296a..b38838c 100644
--- a/lib/classes/Privacy.php
+++ b/lib/classes/Privacy.php
@@ -114,7 +114,7 @@ class Privacy
         }
 
         if (!$section || $section === 'plugins') {
-            foreach (PluginEngine::getPlugins('PrivacyPlugin') as $plugin) {
+            foreach (PluginEngine::getPlugins(PrivacyPlugin::class) as $plugin) {
                 $plugin->exportUserData($storage);
             }
         }
diff --git a/lib/classes/Score.class.php b/lib/classes/Score.class.php
index f7d8ea3..4d114d5 100644
--- a/lib/classes/Score.class.php
+++ b/lib/classes/Score.class.php
@@ -212,7 +212,7 @@ class Score
             'date_column' => 'chdate'
         ];
 
-        foreach (PluginManager::getInstance()->getPlugins('ScorePlugin') as $plugin) {
+        foreach (PluginManager::getInstance()->getPlugins(ScorePlugin::class) as $plugin) {
             foreach ((array) $plugin->getPluginActivityTables() as $table) {
                 if ($table['table']) {
                     $tables[] = $table;
diff --git a/lib/classes/Seminar.class.php b/lib/classes/Seminar.class.php
index dda25ee..8aa3d41 100644
--- a/lib/classes/Seminar.class.php
+++ b/lib/classes/Seminar.class.php
@@ -1565,7 +1565,7 @@ class Seminar
         SeminarCycleDate::deleteBySQL('seminar_id = ' . DBManager::get()->quote($s_id));
 
         // Alle weiteren Postings zu diesem Seminar in den Forums-Modulen löschen
-        foreach (PluginEngine::getPlugins('ForumModule') as $plugin) {
+        foreach (PluginEngine::getPlugins(ForumModule::class) as $plugin) {
             $plugin->deleteContents($s_id);  // delete content irrespective of plugin-activation in the seminar
 
             if ($plugin->isActivated($s_id)) {   // only show a message, if the plugin is activated, to not confuse the user
diff --git a/lib/classes/Siteinfo.php b/lib/classes/Siteinfo.php
index 9043ce3..0d849ca 100644
--- a/lib/classes/Siteinfo.php
+++ b/lib/classes/Siteinfo.php
@@ -480,7 +480,7 @@ class SiteinfoMarkupEngine {
                 // get TopTen of seminars from all ForumModules and add up the
                 // count for seminars with more than one active ForumModule
                 // to get a combined toplist
-                foreach (PluginEngine::getPlugins('ForumModule') as $plugin) {
+                foreach (PluginEngine::getPlugins(ForumModule::class) as $plugin) {
                     $new_seminars = $plugin->getTopTenSeminars();
                     foreach ($new_seminars as $sem) {
                         if (!isset($seminars[$sem['seminar_id']])) {
@@ -589,7 +589,7 @@ class SiteinfoMarkupEngine {
             $count = 0;
 
             // sum up number of postings for all availabe ForumModules
-            foreach (PluginEngine::getPlugins('ForumModule') as $plugin) {
+            foreach (PluginEngine::getPlugins(ForumModule::class) as $plugin) {
                 $count += $plugin->getNumberOfPostings();
             }
 
diff --git a/lib/classes/StudipKing.class.php b/lib/classes/StudipKing.class.php
index 3a61c57..ae5a14e 100644
--- a/lib/classes/StudipKing.class.php
+++ b/lib/classes/StudipKing.class.php
@@ -118,7 +118,7 @@ class StudipKing {
         $kings = [];
 
         // sum up postings for all users from all ForumModules available
-        foreach (PluginEngine::getPlugins('ForumModule') as $plugin) {
+        foreach (PluginEngine::getPlugins(ForumModule::class) as $plugin) {
             $table = $plugin->getEntryTableInfo();
             $query = "SELECT user_id AS id, COUNT(*) AS num FROM ". $table['table'] ." GROUP BY user_id";
             $new_kings = self::select_kings($query);
diff --git a/lib/classes/UserManagement.class.php b/lib/classes/UserManagement.class.php
index 7805594..015e6cd 100644
--- a/lib/classes/UserManagement.class.php
+++ b/lib/classes/UserManagement.class.php
@@ -898,7 +898,7 @@ class UserManagement
 
         // Load privacy plugins to ensure all event handlers can react to the
         // UserDataDidRemove event
-        PluginEngine::getPlugins('PrivacyPlugin');
+        PluginEngine::getPlugins(PrivacyPlugin::class);
 
         // delete user from instituts
         $this->logInstUserDel($this->user_data['auth_user_md5.user_id']);
diff --git a/lib/classes/Visibility.php b/lib/classes/Visibility.php
index 1b87230..99b3907 100644
--- a/lib/classes/Visibility.php
+++ b/lib/classes/Visibility.php
@@ -614,7 +614,7 @@ class Visibility
     private function createHomepagePluginEntries($user)
     {
         self::getUser($user);
-        $homepageplugins = PluginEngine::getPlugins('HomepagePlugin');
+        $homepageplugins = PluginEngine::getPlugins(HomepagePlugin::class);
         foreach ($homepageplugins as $plugin) {
             self::addPrivacySetting($plugin->getPluginName(), ("plugin".$plugin->getPluginId()), 'plugins', 1, $user, null, $plugin->getPluginId());
         }
diff --git a/lib/classes/WidgetHelper.php b/lib/classes/WidgetHelper.php
index ba82ee9..ff4d7a6 100644
--- a/lib/classes/WidgetHelper.php
+++ b/lib/classes/WidgetHelper.php
@@ -348,7 +348,7 @@ class WidgetHelper
      */
     public static function getAvailableWidgets($user_id = null)
     {
-        $all_widgets = PluginEngine::getPlugins('PortalPlugin');
+        $all_widgets = PluginEngine::getPlugins(PortalPlugin::class);
 
         $used_widgets = is_null($user_id)
                 ? []
diff --git a/lib/extern/ExternPage.php b/lib/extern/ExternPage.php
index 308caeb..d3c5ec2 100644
--- a/lib/extern/ExternPage.php
+++ b/lib/extern/ExternPage.php
@@ -110,7 +110,7 @@ abstract class ExternPage
         $page_name = 'ExternPage' . $config->type;
         if (!class_exists($page_name)) {
             // lookup plugins
-            $plugins = PluginEngine::getPlugins('ExternPagePlugin');
+            $plugins = PluginEngine::getPlugins(ExternPagePlugin::class);
             foreach ($plugins as $plugin) {
                 if ($config->type === $plugin->getExternPageName()) {
                     return $plugin->getExternPage($config);
diff --git a/lib/extern/ExternPagePersonDetails.php b/lib/extern/ExternPagePersonDetails.php
index 49c754c..8fb6540 100644
--- a/lib/extern/ExternPagePersonDetails.php
+++ b/lib/extern/ExternPagePersonDetails.php
@@ -439,7 +439,7 @@ class ExternPagePersonDetails extends ExternPage
     private function getContentHomepagePlugins(User $user)
     {
         $content = [];
-        $plugins = PluginEngine::getPlugins('HomepagePlugin');
+        $plugins = PluginEngine::getPlugins(HomepagePlugin::class);
         foreach ($plugins as $plugin) {
             $template = $plugin->getHomepageTemplate($user->id);
             if ($template) {
diff --git a/lib/filesystem/LibraryFile.class.php b/lib/filesystem/LibraryFile.class.php
index 0c2bcb6..c9524e3 100644
--- a/lib/filesystem/LibraryFile.class.php
+++ b/lib/filesystem/LibraryFile.class.php
@@ -212,7 +212,7 @@ class LibraryFile extends StandardFile
         );
         if (Config::get()->LITERATURE_ENABLE && Context::get() && $GLOBALS['perm']->have_studip_perm('tutor', Context::getId())) {
             $plugin_manager = PluginManager::getInstance();
-            $library_plugins = $plugin_manager->getPlugins('LibraryPlugin');
+            $library_plugins = $plugin_manager->getPlugins(LibraryPlugin::class);
             if (count($library_plugins)) {
                 $plugin = $library_plugins[0];
                 $action_menu->addLink(
diff --git a/lib/models/BlubberThread.php b/lib/models/BlubberThread.php
index aa6016f..590a600 100644
--- a/lib/models/BlubberThread.php
+++ b/lib/models/BlubberThread.php
@@ -1081,7 +1081,7 @@ class BlubberThread extends SimpleORMap implements PrivacyObject
                   FROM user_inst
                   WHERE user_id = ?";
         $institut_ids = DBManager::get()->fetchFirst($query, [$user_id]);
-        $blubberplugin = PluginManager::getInstance()->getPlugin("Blubber");
+        $blubberplugin = PluginManager::getInstance()->getPlugin(Blubber::class);
         if (!$blubberplugin) {
             return [];
         }
diff --git a/lib/models/Questionnaire.php b/lib/models/Questionnaire.php
index f29a2de..777182d 100644
--- a/lib/models/Questionnaire.php
+++ b/lib/models/Questionnaire.php
@@ -129,7 +129,7 @@ class Questionnaire extends SimpleORMap implements PrivacyObject
                 return true;
             } else {
                 //now look through all plugin if this assignment is related to plugin contents:
-                foreach (PluginManager::getInstance()->getPlugins("QuestionnaireAssignmentPlugin") as $plugin) {
+                foreach (PluginManager::getInstance()->getPlugins(QuestionnaireAssignmentPlugin::class) as $plugin) {
                     if ($plugin->isQuestionnaireViewable($assignment)) {
                         return true;
                     }
@@ -172,7 +172,7 @@ class Questionnaire extends SimpleORMap implements PrivacyObject
                     return true;
                 } else {
                     //now look through all plugin if this assignment is related to plugin contents:
-                    foreach (PluginManager::getInstance()->getPlugins("QuestionnaireAssignmentPlugin") as $plugin) {
+                    foreach (PluginManager::getInstance()->getPlugins(QuestionnaireAssignmentPlugin::class) as $plugin) {
                         if ($plugin->isQuestionnaireEditable($assignment)) {
                             return true;
                         }
diff --git a/lib/models/User.class.php b/lib/models/User.class.php
index b71464c..a9dbc14 100644
--- a/lib/models/User.class.php
+++ b/lib/models/User.class.php
@@ -1189,7 +1189,7 @@ class User extends AuthUserMd5 implements Range, PrivacyObject, Studip\Calendar\
         // Restliche Daten übertragen
 
         // ForumsModule migrieren
-        foreach (PluginEngine::getPlugins('ForumModule') as $plugin) {
+        foreach (PluginEngine::getPlugins(ForumModule::class) as $plugin) {
             $plugin->migrateUser($old_id, $new_id);
         }
 
diff --git a/lib/navigation/AdminNavigation.php b/lib/navigation/AdminNavigation.php
index a1762c6..a725082 100644
--- a/lib/navigation/AdminNavigation.php
+++ b/lib/navigation/AdminNavigation.php
@@ -126,7 +126,7 @@ class AdminNavigation extends Navigation
                 $navigation->addSubNavigation('banner', new Navigation(_('Werbebanner'), 'dispatch.php/admin/banner'));
             }
 
-            if (PluginManager::getInstance()->getPlugin('CoursewareModule')) {
+            if (PluginManager::getInstance()->getPlugin(CoursewareModule::class)) {
                 $navigation->addSubNavigation(
                     'courseware',
                     new Navigation(
diff --git a/lib/navigation/ContentsNavigation.php b/lib/navigation/ContentsNavigation.php
index f6190e2..a00adb6 100644
--- a/lib/navigation/ContentsNavigation.php
+++ b/lib/navigation/ContentsNavigation.php
@@ -42,7 +42,7 @@ class ContentsNavigation extends Navigation
 
         $this->addSubNavigation('overview', $overview);
 
-        if (PluginManager::getInstance()->getPlugin('CoursewareModule')) {
+        if (PluginManager::getInstance()->getPlugin(CoursewareModule::class)) {
             $courseware = new Navigation(_('Courseware'));
             $courseware->setDescription(_('Erstellen und Sammeln von Lernmaterialien'));
             $courseware->setImage(Icon::create('courseware'));
diff --git a/lib/navigation/ProfileNavigation.php b/lib/navigation/ProfileNavigation.php
index 50dcfec..4827fe4 100644
--- a/lib/navigation/ProfileNavigation.php
+++ b/lib/navigation/ProfileNavigation.php
@@ -139,7 +139,7 @@ class ProfileNavigation extends Navigation
 
         // Add consultations if appropriate
         if (Config::get()->CONSULTATION_ENABLED) {
-            $plugin = PluginEngine::getPlugin('ConsultationModule');
+            $plugin = PluginEngine::getPlugin(ConsultationModule::class);
             if ($current_user && $plugin && PluginManager::getInstance()->isPluginActivatedForUser($plugin->getPluginId(), $current_user->id)) {
                 $this->addSubNavigation('consultation', new ConsultationNavigation($current_user));
             }
diff --git a/lib/navigation/StartNavigation.php b/lib/navigation/StartNavigation.php
index acd5ee3..0a6d52a 100644
--- a/lib/navigation/StartNavigation.php
+++ b/lib/navigation/StartNavigation.php
@@ -222,7 +222,7 @@ class StartNavigation extends Navigation
         // contents
         $navigation = new Navigation(_('Mein Arbeitsplatz'), 'dispatch.php/contents/overview');
 
-        if (PluginManager::getInstance()->getPlugin('CoursewareModule')) {
+        if (PluginManager::getInstance()->getPlugin(CoursewareModule::class)) {
             $navigation->addSubNavigation('courseware',
                 new Navigation(_('Courseware'), 'dispatch.php/contents/courseware'));
         }
diff --git a/lib/plugins/engine/PluginEngine.class.php b/lib/plugins/engine/PluginEngine.class.php
index ecf00cf..25974c5 100644
--- a/lib/plugins/engine/PluginEngine.class.php
+++ b/lib/plugins/engine/PluginEngine.class.php
@@ -3,8 +3,7 @@
 /**
  * Factory Class for the plugin engine
  * @author Dennis Reil, <dennis.reil@offis.de>
- * @package pluginengine
- * @subpackage engine
+ * @template P of StudIPPlugin
  */
 
 class PluginEngine
@@ -38,27 +37,28 @@ class PluginEngine
         global $user, $perm;
 
         // load system plugins
-        self::getPlugins('SystemPlugin');
+        self::getPlugins(SystemPlugin::class);
 
         // load homepage plugins
-        self::getPlugins('HomepagePlugin');
+        self::getPlugins(HomepagePlugin::class);
 
         // load course plugins
         if (Context::getId()) {
-            self::getPlugins('StudipModule');
-            self::getPlugins('StandardPlugin');
+            self::getPlugins(StudipModule::class);
+            self::getPlugins(StandardPlugin::class);
         }
 
         // load admin plugins
         if (is_object($user) && $perm->have_perm('admin')) {
-            self::getPlugins('AdministrationPlugin');
+            self::getPlugins(AdministrationPlugin::class);
         }
     }
 
     /**
      * Get instance of the plugin specified by plugin class name.
      *
-     * @param string $class class name of plugin
+     * @param class-string<P> $class class name of plugin
+     * @return P
      */
     public static function getPlugin ($class)
     {
@@ -70,10 +70,9 @@ class PluginEngine
      * returns all enabled plugins. The optional context parameter can be
      * used to get only plugins that are activated in the given context.
      *
-     * @template T
-     * @param T $type plugin type or null (all types)
+     * @param class-string<P>|null $type plugin type or null (all types)
      * @param string $context context range id (optional)
-     * @return T[] all plugins of the specified type
+     * @return P[]|StudIPPlugin[] all plugins of the specified type
      */
     public static function getPlugins ($type, $context = null)
     {
diff --git a/lib/plugins/engine/PluginManager.class.php b/lib/plugins/engine/PluginManager.class.php
index f08b5fa..fc81d7f 100644
--- a/lib/plugins/engine/PluginManager.class.php
+++ b/lib/plugins/engine/PluginManager.class.php
@@ -1,14 +1,11 @@
 <?php
-# Lifter010: TODO
-/*
+/**
  * PluginManager.class.php - plugin manager for Stud.IP
  *
- * Copyright (c) 2009  Elmar Ludwig
+ * @copyright  2009  Elmar Ludwig
+ * @license GPL2 or any later version
  *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
+ * @template P of StudIPPlugin
  */
 
 class PluginManager
@@ -576,7 +573,7 @@ class PluginManager
      * Get instance of the plugin specified by plugin meta data.
      *
      * @param array $plugin_info plugin meta data
-     * @return object
+     * @return P
      */
     protected function getCachedPlugin ($plugin_info)
     {
@@ -603,8 +600,8 @@ class PluginManager
     /**
      * Get instance of the plugin specified by plugin class name.
      *
-     * @param string $class class name of plugin
-     * @return object
+     * @param class-string<P> $class class name of plugin
+     * @return P|null
      */
     public function getPlugin ($class)
     {
@@ -623,7 +620,7 @@ class PluginManager
      * Get instance of the plugin specified by plugin id.
      *
      * @param int $id id of the plugin
-     * @return object $plugin
+     * @return P|null $plugin
      */
     public function getPluginById ($id)
     {
@@ -643,8 +640,9 @@ class PluginManager
      * returns all enabled plugins. The optional context parameter can be
      * used to get only plugins that are activated in the given context.
      *
-     * @param string $type plugin type or null (all types)
+     * @param class-string<P>|null $type plugin type or null (all types)
      * @param string $context context range id (optional)
+     * @return P[]|StudIPPlugin[]
      */
     public function getPlugins ($type, $context = null)
     {