first commit

lib/classes/plugininfo/antivirus.php

@@ -0,0 +1,171 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core_antivirus
+ * @copyright  2015 Ruslan Kabalin, Lancaster University.
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for Antiviruses
+ *
+ * @package    core_antivirus
+ * @copyright  2015 Ruslan Kabalin, Lancaster University.
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class antivirus extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        if (empty($CFG->antiviruses)) {
+            return array();
+        }
+
+        $enabled = array();
+        foreach (explode(',', $CFG->antiviruses) as $antivirus) {
+            $enabled[$antivirus] = $antivirus;
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+
+        $haschanged = false;
+        $plugins = [];
+        if (!empty($CFG->antiviruses)) {
+            $plugins = array_flip(explode(',', $CFG->antiviruses));
+        }
+        // Only set visibility if it's different from the current value.
+        if ($enabled && !array_key_exists($pluginname, $plugins)) {
+            $plugins[$pluginname] = $pluginname;
+            $haschanged = true;
+        } else if (!$enabled && array_key_exists($pluginname, $plugins)) {
+            unset($plugins[$pluginname]);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            $new = implode(',', array_flip($plugins));
+            add_to_config_log('antiviruses', $CFG->antiviruses, $new, 'core');
+            set_config('antiviruses', $new);
+            // Reset caches.
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Return the node name to use in admin settings menu for this plugin.
+     *
+     * @return string node name
+     */
+    public function get_settings_section_name() {
+        return 'antivirussettings' . $this->name;
+    }
+
+    /**
+     * Loads plugin settings to the settings tree
+     *
+     * This function usually includes settings.php file in plugins folder.
+     * Alternatively it can create a link to some settings page (instance of admin_externalpage)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig whether the current user has moodle/site:config capability
+     */
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $antivirus = $this;  // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig or !file_exists($this->full_path('settings.php'))) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+        include($this->full_path('settings.php')); // This may also set $settings to null.
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Clamav antivirus can not be uninstalled.
+     */
+    public function is_uninstall_allowed() {
+        if ($this->name === 'clamav') {
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/settings.php', array('section' => 'manageantiviruses'));
+    }
+
+    /**
+     * Pre-uninstall hook.
+     */
+    public function uninstall_cleanup() {
+        global $CFG;
+
+        if (!empty($CFG->antiviruses)) {
+            $antiviruses = explode(',', $CFG->antiviruses);
+            $antiviruses = array_unique($antiviruses);
+        } else {
+            $antiviruses = array();
+        }
+        if (($key = array_search($this->name, $antiviruses)) !== false) {
+            unset($antiviruses[$key]);
+            set_config('antiviruses', implode(',', $antiviruses));
+        }
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/auth.php

@@ -0,0 +1,171 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for authentication plugins
+ */
+class auth extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    public function is_uninstall_allowed() {
+        global $DB;
+
+        if (in_array($this->name, array('manual', 'nologin', 'webservice', 'mnet'))) {
+            return false;
+        }
+
+        return !$DB->record_exists('user', array('auth'=>$this->name));
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        // These two are always enabled and can't be disabled.
+        $enabled = array('nologin'=>'nologin', 'manual'=>'manual');
+        foreach (explode(',', $CFG->auth) as $auth) {
+            $enabled[$auth] = $auth;
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+
+        $haschanged = false;
+        $plugins = [];
+        if (!empty($CFG->auth)) {
+            $plugins = array_flip(explode(',', $CFG->auth));
+        }
+        // Only set visibility if it's different from the current value.
+        if ($enabled && !array_key_exists($pluginname, $plugins)) {
+            $plugins[$pluginname] = $pluginname;
+            $haschanged = true;
+        } else if (!$enabled && array_key_exists($pluginname, $plugins)) {
+            unset($plugins[$pluginname]);
+            $haschanged = true;
+
+            if ($pluginname == $CFG->registerauth) {
+                set_config('registerauth', '');
+            }
+        }
+
+        if ($haschanged) {
+            $new = implode(',', array_flip($plugins));
+            add_to_config_log('auth', $CFG->auth, $new, 'core');
+            set_config('auth', $new);
+            // Remove stale sessions.
+            \core\session\manager::gc();
+            // Reset caches.
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    public function get_settings_section_name() {
+        return 'authsetting' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $auth = $this;       // Also to be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            // TODO: finish implementation of common settings - locking, etc.
+            $settings = new admin_settingpage($section, $this->displayname,
+                'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/settings.php', array('section'=>'manageauths'));
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        global $CFG;
+
+        if (!empty($CFG->auth)) {
+            $auths = explode(',', $CFG->auth);
+            $auths = array_unique($auths);
+        } else {
+            $auths = array();
+        }
+        if (($key = array_search($this->name, $auths)) !== false) {
+            unset($auths[$key]);
+            $value = implode(',', $auths);
+            add_to_config_log('auth', $CFG->auth, $value, 'core');
+            set_config('auth', $value);
+        }
+
+        if (!empty($CFG->registerauth) and $CFG->registerauth === $this->name) {
+            unset_config('registerauth');
+        }
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/availability.php

@@ -0,0 +1,136 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Class for availability plugins.
+ *
+ * @package core
+ * @copyright 2014 The Open University
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+
+/**
+ * Class for availability plugins.
+ *
+ * @package core
+ * @copyright 2014 The Open University
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class availability extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    public static function get_enabled_plugins() {
+        global $DB;
+
+        // Get all available plugins.
+        $plugins = \core_plugin_manager::instance()->get_installed_plugins('availability');
+        if (!$plugins) {
+            return array();
+        }
+
+        // Check they are enabled using get_config (which is cached and hopefully fast).
+        $enabled = array();
+        foreach ($plugins as $plugin => $version) {
+            $disabled = get_config('availability_' . $plugin, 'disabled');
+            if (empty($disabled)) {
+                $enabled[$plugin] = $plugin;
+            }
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $plugin = 'availability_' . $pluginname;
+        $oldvalue = get_config($plugin, 'disabled');
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            set_config('disabled', $disabled, $plugin);
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config('disabled', $plugin);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('disabled', $oldvalue, $disabled, $plugin);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Defines if there should be a way to uninstall the plugin via the administration UI.
+     *
+     * @return bool
+     */
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Get the name for the settings section.
+     *
+     * @return string
+     */
+    public function get_settings_section_name() {
+        return 'availabilitysetting' . $this->name;
+    }
+
+    /**
+     * Load the global settings for a particular availability plugin (if there are any)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php
+        $availability = $this; // Also to be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+}

lib/classes/plugininfo/base.php

@@ -0,0 +1,720 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use coding_exception;
+use core_component;
+use core_plugin_manager;
+use moodle_url;
+
+/**
+ * Base class providing access to the information about a plugin
+ *
+ * @property-read string component the component name, type_name
+ */
+abstract class base {
+
+    /** @var string the plugintype name, eg. mod, auth or workshopform */
+    public $type;
+    /** @var string full path to the location of all the plugins of this type */
+    public $typerootdir;
+    /** @var string the plugin name, eg. assignment, ldap */
+    public $name;
+    /** @var string the localized plugin name */
+    public $displayname;
+    /** @var string the plugin source, one of core_plugin_manager::PLUGIN_SOURCE_xxx constants */
+    public $source;
+    /** @var string fullpath to the location of this plugin */
+    public $rootdir;
+    /** @var int|string the version of the plugin's source code */
+    public $versiondisk;
+    /** @var int|string the version of the installed plugin */
+    public $versiondb;
+    /** @var int|float|string required version of Moodle core  */
+    public $versionrequires;
+    /** @var array explicitly supported branches of Moodle core  */
+    public $pluginsupported;
+    /** @var int first incompatible branch of Moodle core  */
+    public $pluginincompatible;
+    /** @var mixed human-readable release information */
+    public $release;
+    /** @var array other plugins that this one depends on, lazy-loaded by {@link get_other_required_plugins()} */
+    public $dependencies;
+    /** @var int number of instances of the plugin - not supported yet */
+    public $instances;
+    /** @var int order of the plugin among other plugins of the same type - not supported yet */
+    public $sortorder;
+    /** @var core_plugin_manager the plugin manager this plugin info is part of */
+    public $pluginman;
+
+    /** @var array|null array of {@link \core\update\info} for this plugin */
+    protected $availableupdates;
+
+    /** @var int Move a plugin up in the plugin order */
+    public const MOVE_UP = -1;
+
+    /** @var int Move a plugin down in the plugin order */
+    public const MOVE_DOWN = 1;
+
+    /** @var array hold $plugin->supported in version.php */
+    public $supported;
+
+    /** @var int hold $plugin->incompatible in version.php  */
+    public $incompatible;
+
+    /** @var string Name of the plugin */
+    public $component = '';
+
+    /**
+     * Whether this plugintype supports its plugins being disabled.
+     *
+     * @return bool
+     */
+    public static function plugintype_supports_disabling(): bool {
+        return false;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        return null;
+    }
+
+    /**
+     * Enable or disable a plugin.
+     * When possible, the change will be stored into the config_log table, to let admins check when/who has modified it.
+     *
+     * @param string $pluginname The plugin name to enable/disable.
+     * @param int $enabled Whether the pluginname should be enabled (1) or not (0). This is an integer because some plugins, such
+     * as filters or repositories, might support more statuses than just enabled/disabled.
+     *
+     * @return bool Whether $pluginname has been updated or not.
+     */
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        return false;
+    }
+
+    /**
+     * Returns current status for a pluginname.
+     *
+     * @param string $pluginname The plugin name to check.
+     * @return int The current status (enabled, disabled...) of $pluginname.
+     */
+    public static function get_enabled_plugin(string $pluginname): int {
+        $enabledplugins = static::get_enabled_plugins();
+        $value = $enabledplugins && array_key_exists($pluginname, $enabledplugins);
+        return (int) $value;
+    }
+
+    /**
+     * Gathers and returns the information about all plugins of the given type,
+     * either on disk or previously installed.
+     *
+     * This is supposed to be used exclusively by the plugin manager when it is
+     * populating its tree of plugins.
+     *
+     * @param string $type the name of the plugintype, eg. mod, auth or workshopform
+     * @param string $typerootdir full path to the location of the plugin dir
+     * @param string $typeclass the name of the actually called class
+     * @param core_plugin_manager $pluginman the plugin manager calling this method
+     * @return array of plugintype classes, indexed by the plugin name
+     */
+    public static function get_plugins($type, $typerootdir, $typeclass, $pluginman) {
+        // Get the information about plugins at the disk.
+        $plugins = core_component::get_plugin_list($type);
+        $return = array();
+        foreach ($plugins as $pluginname => $pluginrootdir) {
+            $return[$pluginname] = self::make_plugin_instance($type, $typerootdir,
+                $pluginname, $pluginrootdir, $typeclass, $pluginman);
+        }
+
+        // Fetch missing incorrectly uninstalled plugins.
+        $plugins = $pluginman->get_installed_plugins($type);
+
+        foreach ($plugins as $name => $version) {
+            if (isset($return[$name])) {
+                continue;
+            }
+            $plugin              = new $typeclass();
+            $plugin->type        = $type;
+            $plugin->typerootdir = $typerootdir;
+            $plugin->name        = $name;
+            $plugin->component   = $plugin->type.'_'.$plugin->name;
+            $plugin->rootdir     = null;
+            $plugin->displayname = $name;
+            $plugin->versiondb   = $version;
+            $plugin->pluginman   = $pluginman;
+            $plugin->init_is_standard();
+
+            $return[$name] = $plugin;
+        }
+
+        return $return;
+    }
+
+    /**
+     * Makes a new instance of the plugininfo class
+     *
+     * @param string $type the plugin type, eg. 'mod'
+     * @param string $typerootdir full path to the location of all the plugins of this type
+     * @param string $name the plugin name, eg. 'workshop'
+     * @param string $namerootdir full path to the location of the plugin
+     * @param string $typeclass the name of class that holds the info about the plugin
+     * @param core_plugin_manager $pluginman the plugin manager of the new instance
+     * @return base the instance of $typeclass
+     */
+    protected static function make_plugin_instance($type, $typerootdir, $name, $namerootdir, $typeclass, $pluginman) {
+        $plugin              = new $typeclass();
+        $plugin->type        = $type;
+        $plugin->typerootdir = $typerootdir;
+        $plugin->name        = $name;
+        $plugin->rootdir     = $namerootdir;
+        $plugin->pluginman   = $pluginman;
+        $plugin->component   = $plugin->type.'_'.$plugin->name;
+
+        $plugin->init_display_name();
+        $plugin->load_disk_version();
+        $plugin->load_db_version();
+        $plugin->init_is_standard();
+
+        return $plugin;
+    }
+
+    /**
+     * Is this plugin already installed and updated?
+     * @return bool true if plugin installed and upgraded.
+     */
+    public function is_installed_and_upgraded() {
+        if (!$this->rootdir) {
+            return false;
+        }
+        if ($this->versiondb === null and $this->versiondisk === null) {
+            // There is no version.php or version info inside it.
+            return false;
+        }
+
+        return ((float)$this->versiondb === (float)$this->versiondisk);
+    }
+
+    /**
+     * Sets {@link $displayname} property to a localized name of the plugin
+     */
+    public function init_display_name() {
+        if (!get_string_manager()->string_exists('pluginname', $this->component)) {
+            $this->displayname = '[pluginname,' . $this->component . ']';
+        } else {
+            $this->displayname = get_string('pluginname', $this->component);
+        }
+    }
+
+    /**
+     * Magic method getter, redirects to read only values.
+     *
+     * @param string $name
+     * @return mixed
+     */
+    public function __get($name) {
+        switch ($name) {
+            case 'component': return $this->type . '_' . $this->name;
+
+            default:
+                debugging('Invalid plugin property accessed! '.$name);
+                return null;
+        }
+    }
+
+    /**
+     * Return the full path name of a file within the plugin.
+     *
+     * No check is made to see if the file exists.
+     *
+     * @param string $relativepath e.g. 'version.php'.
+     * @return string e.g. $CFG->dirroot . '/mod/quiz/version.php'.
+     */
+    public function full_path($relativepath) {
+        if (empty($this->rootdir)) {
+            return '';
+        }
+        return $this->rootdir . '/' . $relativepath;
+    }
+
+    /**
+     * Sets {@link $versiondisk} property to a numerical value representing the
+     * version of the plugin's source code.
+     *
+     * If the value is null after calling this method, either the plugin
+     * does not use versioning (typically does not have any database
+     * data) or is missing from disk.
+     */
+    public function load_disk_version() {
+        $versions = $this->pluginman->get_present_plugins($this->type);
+
+        $this->versiondisk = null;
+        $this->versionrequires = null;
+        $this->pluginsupported = null;
+        $this->pluginincompatible = null;
+        $this->dependencies = array();
+
+        if (!isset($versions[$this->name])) {
+            return;
+        }
+
+        $plugin = $versions[$this->name];
+
+        if (isset($plugin->version)) {
+            $this->versiondisk = $plugin->version;
+        }
+        if (isset($plugin->requires)) {
+            $this->versionrequires = $plugin->requires;
+        }
+        if (isset($plugin->release)) {
+            $this->release = $plugin->release;
+        }
+        if (isset($plugin->dependencies)) {
+            $this->dependencies = $plugin->dependencies;
+        }
+
+        // Check that supports and incompatible are wellformed, exception otherwise.
+        if (isset($plugin->supported)) {
+            // Checks for structure of supported.
+            $isint = (is_int($plugin->supported[0]) && is_int($plugin->supported[1]));
+            $isrange = ($plugin->supported[0] <= $plugin->supported[1] && count($plugin->supported) == 2);
+
+            if (is_array($plugin->supported) && $isint && $isrange) {
+                $this->pluginsupported = $plugin->supported;
+            } else {
+                throw new coding_exception('Incorrect syntax in plugin supported declaration in '."$this->name");
+            }
+        }
+
+        if (isset($plugin->incompatible) && $plugin->incompatible !== null) {
+            if (((is_string($plugin->incompatible) && ctype_digit($plugin->incompatible)) || is_int($plugin->incompatible))
+                    && (int) $plugin->incompatible > 0) {
+                $this->pluginincompatible = intval($plugin->incompatible);
+            } else {
+                throw new coding_exception('Incorrect syntax in plugin incompatible declaration in '."$this->name");
+            }
+        }
+
+    }
+
+    /**
+     * Get the list of other plugins that this plugin requires to be installed.
+     *
+     * @return array with keys the frankenstyle plugin name, and values either
+     *      a version string (like '2011101700') or the constant ANY_VERSION.
+     */
+    public function get_other_required_plugins() {
+        if (is_null($this->dependencies)) {
+            $this->load_disk_version();
+        }
+        return $this->dependencies;
+    }
+
+    /**
+     * Is this is a subplugin?
+     *
+     * @return boolean
+     */
+    public function is_subplugin() {
+        return ($this->get_parent_plugin() !== false);
+    }
+
+    /**
+     * If I am a subplugin, return the name of my parent plugin.
+     *
+     * @return string|bool false if not a subplugin, name of the parent otherwise
+     */
+    public function get_parent_plugin() {
+        return $this->pluginman->get_parent_of_subplugin($this->type);
+    }
+
+    /**
+     * Sets {@link $versiondb} property to a numerical value representing the
+     * currently installed version of the plugin.
+     *
+     * If the value is null after calling this method, either the plugin
+     * does not use versioning (typically does not have any database
+     * data) or has not been installed yet.
+     */
+    public function load_db_version() {
+        $versions = $this->pluginman->get_installed_plugins($this->type);
+
+        if (isset($versions[$this->name])) {
+            $this->versiondb = $versions[$this->name];
+        } else {
+            $this->versiondb = null;
+        }
+    }
+
+    /**
+     * Sets {@link $source} property to one of core_plugin_manager::PLUGIN_SOURCE_xxx
+     * constants.
+     *
+     * If the property's value is null after calling this method, then
+     * the type of the plugin has not been recognized and you should throw
+     * an exception.
+     */
+    public function init_is_standard() {
+
+        $pluginman = $this->pluginman;
+        $standard = $pluginman::standard_plugins_list($this->type);
+
+        if ($standard !== false) {
+            $standard = array_flip($standard);
+            if (isset($standard[$this->name])) {
+                $this->source = core_plugin_manager::PLUGIN_SOURCE_STANDARD;
+            } else if (!is_null($this->versiondb) and is_null($this->versiondisk)
+                and $pluginman::is_deleted_standard_plugin($this->type, $this->name)) {
+                $this->source = core_plugin_manager::PLUGIN_SOURCE_STANDARD; // To be deleted.
+            } else {
+                $this->source = core_plugin_manager::PLUGIN_SOURCE_EXTENSION;
+            }
+        }
+    }
+
+    /**
+     * Returns true if the plugin is shipped with the official distribution
+     * of the current Moodle version, false otherwise.
+     *
+     * @return bool
+     */
+    public function is_standard() {
+        return $this->source === core_plugin_manager::PLUGIN_SOURCE_STANDARD;
+    }
+
+    /**
+     * Returns true if the the given Moodle version is enough to run this plugin
+     *
+     * @param string|int|double $moodleversion
+     * @return bool
+     */
+    public function is_core_dependency_satisfied($moodleversion) {
+
+        if (empty($this->versionrequires)) {
+            return true;
+
+        } else {
+            return (double)$this->versionrequires <= (double)$moodleversion;
+        }
+    }
+
+    /**
+     * Returns true if the the given moodle branch is not stated incompatible with the plugin
+     *
+     * @param int $branch the moodle branch number
+     * @return bool true if not incompatible with moodle branch
+     */
+    public function is_core_compatible_satisfied(int $branch): bool {
+        if (!empty($this->pluginincompatible) && ($branch >= $this->pluginincompatible)) {
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    /**
+     * Returns the status of the plugin
+     *
+     * @return string one of core_plugin_manager::PLUGIN_STATUS_xxx constants
+     */
+    public function get_status() {
+
+        $pluginman = $this->pluginman;
+
+        if (is_null($this->versiondb) and is_null($this->versiondisk)) {
+            return core_plugin_manager::PLUGIN_STATUS_NODB;
+
+        } else if (is_null($this->versiondb) and !is_null($this->versiondisk)) {
+            return core_plugin_manager::PLUGIN_STATUS_NEW;
+
+        } else if (!is_null($this->versiondb) and is_null($this->versiondisk)) {
+            if ($pluginman::is_deleted_standard_plugin($this->type, $this->name)) {
+                return core_plugin_manager::PLUGIN_STATUS_DELETE;
+            } else {
+                return core_plugin_manager::PLUGIN_STATUS_MISSING;
+            }
+
+        } else if ((float)$this->versiondb === (float)$this->versiondisk) {
+            // Note: the float comparison should work fine here
+            //       because there are no arithmetic operations with the numbers.
+            return core_plugin_manager::PLUGIN_STATUS_UPTODATE;
+
+        } else if ($this->versiondb < $this->versiondisk) {
+            return core_plugin_manager::PLUGIN_STATUS_UPGRADE;
+
+        } else if ($this->versiondb > $this->versiondisk) {
+            return core_plugin_manager::PLUGIN_STATUS_DOWNGRADE;
+
+        } else {
+            // $version = pi(); and similar funny jokes - hopefully Donald E. Knuth will never contribute to Moodle ;-)
+            throw new coding_exception('Unable to determine plugin state, check the plugin versions');
+        }
+    }
+
+    /**
+     * Returns the information about plugin availability
+     *
+     * True means that the plugin is enabled. False means that the plugin is
+     * disabled. Null means that the information is not available, or the
+     * plugin does not support configurable availability or the availability
+     * can not be changed.
+     *
+     * @return null|bool
+     */
+    public function is_enabled() {
+        if (!$this->rootdir) {
+            // Plugin missing.
+            return false;
+        }
+
+        $enabled = $this->pluginman->get_enabled_plugins($this->type);
+
+        if (!is_array($enabled)) {
+            return null;
+        }
+
+        return isset($enabled[$this->name]);
+    }
+
+    /**
+     * If there are updates for this plugin available, returns them.
+     *
+     * Returns array of {@link \core\update\info} objects, if some update
+     * is available. Returns null if there is no update available or if the update
+     * availability is unknown.
+     *
+     * Populates the property {@link $availableupdates} on first call (lazy
+     * loading).
+     *
+     * @return array|null
+     */
+    public function available_updates() {
+
+        if ($this->availableupdates === null) {
+            // Lazy load the information about available updates.
+            $this->availableupdates = $this->pluginman->load_available_updates_for_plugin($this->component);
+        }
+
+        if (empty($this->availableupdates) or !is_array($this->availableupdates)) {
+            $this->availableupdates = array();
+            return null;
+        }
+
+        $updates = array();
+
+        foreach ($this->availableupdates as $availableupdate) {
+            if ($availableupdate->version > $this->versiondisk) {
+                $updates[] = $availableupdate;
+            }
+        }
+
+        if (empty($updates)) {
+            return null;
+        }
+
+        return $updates;
+    }
+
+    /**
+     * Returns the node name used in admin settings menu for this plugin settings (if applicable)
+     *
+     * @return null|string node name or null if plugin does not create settings node (default)
+     */
+    public function get_settings_section_name() {
+        return null;
+    }
+
+    /**
+     * Returns the URL of the plugin settings screen
+     *
+     * Null value means that the plugin either does not have the settings screen
+     * or its location is not available via this library.
+     *
+     * @return null|moodle_url
+     */
+    public function get_settings_url(): ?moodle_url {
+        $section = $this->get_settings_section_name();
+        if ($section === null) {
+            return null;
+        }
+
+        $settings = admin_get_root()->locate($section);
+        if ($settings && $settings instanceof \core_admin\local\settings\linkable_settings_page) {
+            return $settings->get_settings_page_url();
+        }
+
+        return null;
+    }
+
+    /**
+     * Loads plugin settings to the settings tree
+     *
+     * This function usually includes settings.php file in plugins folder.
+     * Alternatively it can create a link to some settings page (instance of admin_externalpage)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig whether the current user has moodle/site:config capability
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+    }
+
+    /**
+     * Should there be a way to uninstall the plugin via the administration UI.
+     *
+     * By default uninstallation is not allowed, plugin developers must enable it explicitly!
+     *
+     * @return bool
+     */
+    public function is_uninstall_allowed() {
+        return false;
+    }
+
+    /**
+     * Optional extra warning before uninstallation, for example number of uses in courses.
+     *
+     * @return string
+     */
+    public function get_uninstall_extra_warning() {
+        return '';
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        // Override when extending class,
+        // do not forget to call parent::pre_uninstall_cleanup() at the end.
+    }
+
+    /**
+     * Returns relative directory of the plugin with heading '/'
+     *
+     * @return string
+     */
+    public function get_dir() {
+        global $CFG;
+
+        if (!isset($this->rootdir)) {
+            return '';
+        }
+
+        return substr($this->rootdir, strlen($CFG->dirroot));
+    }
+
+    /**
+     * Hook method to implement certain steps when uninstalling the plugin.
+     *
+     * This hook is called by {@link core_plugin_manager::uninstall_plugin()} so
+     * it is basically usable only for those plugin types that use the default
+     * uninstall tool provided by {@link self::get_default_uninstall_url()}.
+     *
+     * @param \progress_trace $progress traces the process
+     * @return bool true on success, false on failure
+     */
+    public function uninstall(\progress_trace $progress) {
+        return true;
+    }
+
+    /**
+     * Where should we return after plugin of this type is uninstalled?
+     * @param string $return
+     * @return moodle_url
+     */
+    public function get_return_url_after_uninstall($return) {
+        if ($return === 'manage') {
+            if ($url = $this->get_manage_url()) {
+                return $url;
+            }
+        }
+        return new moodle_url('/admin/plugins.php#plugin_type_cell_'.$this->type);
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return null;
+    }
+
+    /**
+     * Returns URL to a script that handles common plugin uninstall procedure.
+     *
+     * This URL is intended for all plugin uninstallations.
+     *
+     * @param string $return either 'overview' or 'manage'
+     * @return moodle_url
+     */
+    final public function get_default_uninstall_url($return = 'overview') {
+        return new moodle_url('/admin/plugins.php', array(
+            'uninstall' => $this->component,
+            'confirm' => 0,
+            'return' => $return,
+        ));
+    }
+
+    /**
+     * Whether this plugintype supports ordering of plugins using native functionality.
+     *
+     * Please note that plugintypes which pre-date this native functionality may still support ordering
+     * but will not use the built-in functionality.
+     *
+     * @return bool
+     */
+    public static function plugintype_supports_ordering(): bool {
+        return false;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     *
+     * @param bool $enabledonly Show all plugins, or only those which are enabled
+     * @return array|null of sorted plugins $pluginname => $pluginname, null means unknown
+     */
+    public static function get_sorted_plugins(bool $enabledonly = false): ?array {
+        return null;
+    }
+
+    /**
+     * Change the order of the plugin relative to other plugins in the plugintype.
+     *
+     * When possible, the change will be stored into the config_log table, to let admins check when/who has modified it.
+     *
+     * @param string $pluginname The plugin name to enable/disable.
+     * @param int $direction The direction to move the plugin. Negative numbers mean up, Positive mean down.
+     * @return bool Whether $pluginname has been updated or not.
+     */
+    public static function change_plugin_order(string $pluginname, int $direction): bool {
+        return false;
+    }
+}

lib/classes/plugininfo/block.php

@@ -0,0 +1,196 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for page side blocks
+ */
+class block extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $DB;
+
+        return $DB->get_records_menu('block', array('visible'=>1), 'name ASC', 'name, name AS val');
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $DB;
+
+        if (!$block = $DB->get_record('block', ['name' => $pluginname])) {
+            throw new \moodle_exception('blockdoesnotexist', 'error');
+        }
+
+        $haschanged = false;
+
+        // Only set visibility if it's different from the current value.
+        if ($block->visible != $enabled) {
+            // Set block visibility.
+            $DB->set_field('block', 'visible', $enabled, ['id' => $block->id]);
+            $haschanged = true;
+
+            // Include this information into config changes table.
+            add_to_config_log('block_visibility', $block->visible, $enabled, $pluginname);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Magic method getter, redirects to read only values.
+     *
+     * For block plugins pretends the object has 'visible' property for compatibility
+     * with plugins developed for Moodle version below 2.4
+     *
+     * @param string $name
+     * @return mixed
+     */
+    public function __get($name) {
+        if ($name === 'visible') {
+            debugging('This is now an instance of plugininfo_block, please use $block->is_enabled() instead of $block->visible', DEBUG_DEVELOPER);
+            return ($this->is_enabled() !== false);
+        }
+        return parent::__get($name);
+    }
+
+    public function init_display_name() {
+
+        if (get_string_manager()->string_exists('pluginname', 'block_' . $this->name)) {
+            $this->displayname = get_string('pluginname', 'block_' . $this->name);
+
+        } else if (($block = block_instance($this->name)) !== false) {
+            $this->displayname = $block->get_title();
+
+        } else {
+            parent::init_display_name();
+        }
+    }
+
+    public function get_settings_section_name() {
+        return 'blocksetting' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $block = $this;      // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        if (!$hassiteconfig || (($blockinstance = block_instance($this->name)) === false)) {
+            return;
+        }
+
+        $settings = null;
+        if ($blockinstance->has_config()) {
+            if (file_exists($this->full_path('settings.php'))) {
+                $settings = new admin_settingpage($section, $this->displayname,
+                    'moodle/site:config', $this->is_enabled() === false);
+                include($this->full_path('settings.php')); // This may also set $settings to null.
+            }
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    public function is_uninstall_allowed() {
+        if ($this->name === 'settings' or $this->name === 'navigation') {
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/blocks.php');
+    }
+
+    /**
+     * Warning with number of block instances.
+     *
+     * @return string
+     */
+    public function get_uninstall_extra_warning() {
+        global $DB;
+
+        if (!$count = $DB->count_records('block_instances', array('blockname'=>$this->name))) {
+            return '';
+        }
+
+        return '<p>'.get_string('uninstallextraconfirmblock', 'core_plugin', array('instances'=>$count)).'</p>';
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        global $DB, $CFG;
+
+        if ($block = $DB->get_record('block', array('name'=>$this->name))) {
+            // Inform block it's about to be deleted.
+            $blockobject = block_instance($block->name);
+            if ($blockobject) {
+                $blockobject->before_delete();  // Only if we can create instance, block might have been already removed.
+            }
+
+            // First delete instances and related contexts.
+            $instances = $DB->get_records('block_instances', array('blockname' => $block->name));
+            foreach ($instances as $instance) {
+                blocks_delete_instance($instance);
+            }
+
+            // Delete block.
+            $DB->delete_records('block', array('id'=>$block->id));
+        }
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/cachelock.php

@@ -0,0 +1,36 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class cachelock extends base {
+
+    public function is_uninstall_allowed() {
+        return false;
+    }
+}

lib/classes/plugininfo/cachestore.php

@@ -0,0 +1,42 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for cache store plugins
+ */
+class cachestore extends base {
+
+    public function is_uninstall_allowed() {
+        $instance = \cache_config::instance();
+        foreach ($instance->get_all_stores() as $store) {
+            if ($store['plugin'] == $this->name) {
+                return false;
+            }
+        }
+        return true;
+    }
+}

lib/classes/plugininfo/calendartype.php

@@ -0,0 +1,75 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use part_of_admin_tree, admin_settingpage;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for calendar type plugins.
+ */
+class calendartype extends base {
+
+    public function is_uninstall_allowed() {
+        // We can delete all calendar types, except Gregorian. Gregorian comes with core and was the calendar
+        // type used before the calendar types were introduced as plugins in Moodle. If all calendar types were
+        // deleted then Moodle would break completely wherever any dates are displayed.
+        if ($this->name !== 'gregorian') {
+            return true;
+        }
+
+        return false;
+    }
+
+    public function get_settings_section_name() {
+        return 'calendartype_' . $this->name . '_settings';
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $qtype = $this;      // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        $systemcontext = \context_system::instance();
+        if (($hassiteconfig) &&
+            file_exists($this->full_path('settings.php'))) {
+            $settings = new admin_settingpage($section, $this->displayname,
+                'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+}

lib/classes/plugininfo/communication.php

@@ -0,0 +1,139 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core\plugininfo;
+
+use admin_settingpage;
+use core_communication\processor;
+use core_plugin_manager;
+use moodle_url;
+
+/**
+ * Class for communication provider.
+ *
+ * @package    core
+ * @copyright  2023 Huong Nguyen <huongnv13@gmail.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class communication extends base {
+
+    public static function get_manage_url(): ?moodle_url {
+        if (!\core_communication\api::is_available()) {
+            return null;
+        }
+
+        return new moodle_url('/admin/settings.php', ['section' => 'managecommunicationproviders']);
+    }
+
+    public function get_settings_section_name(): string {
+        return $this->type . '_' . $this->name;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $plugin = 'communication_' . $pluginname;
+        $oldvalue = get_config($plugin, 'disabled');
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            set_config('disabled', $disabled, $plugin);
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config('disabled', $plugin);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('disabled', $oldvalue, $disabled, $plugin);
+            core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    public static function get_enabled_plugins(): ?array {
+        $pluginmanager = core_plugin_manager::instance();
+        $plugins = $pluginmanager->get_installed_plugins('communication');
+
+        if (!$plugins) {
+            return [];
+        }
+
+        $plugins = array_keys($plugins);
+
+        // Filter to return only enabled plugins.
+        $enabled = [];
+        foreach ($plugins as $plugin) {
+            $disabled = get_config('communication_' . $plugin, 'disabled');
+            if (empty($disabled)) {
+                $enabled[$plugin] = $plugin;
+            }
+        }
+        return $enabled;
+    }
+
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this;      // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            $settings = new admin_settingpage($section, $this->displayname,
+                'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    public function is_uninstall_allowed(): bool {
+        if (in_array($this->name, \core_plugin_manager::standard_plugins_list('communication'))) {
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Checks if a communication plugin is ready to be used.
+     * It checks the plugin status as well as the plugin is missing or not.
+     *
+     * @param string $fullpluginname the name of the plugin
+     * @return bool
+     */
+    public static function is_plugin_enabled($fullpluginname): bool {
+        $pluginmanager = \core_plugin_manager::instance();
+        $communicationinfo = $pluginmanager->get_plugin_info($fullpluginname);
+        if (empty($communicationinfo)) {
+            return false;
+        }
+        $communicationavailable = $communicationinfo->get_status();
+        return !($communicationavailable === \core_plugin_manager::PLUGIN_STATUS_MISSING ||
+            !empty(get_config($fullpluginname, 'disabled')));
+    }
+
+}

lib/classes/plugininfo/contenttype.php

@@ -0,0 +1,228 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core_contentbank
+ * @copyright  2020 Amaia Anabitarte <amaia@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+/**
+ * Class for contentbank plugins
+ *
+ * @package    core_contentbank
+ * @copyright  2020 Amaia Anabitarte <amaia@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class contenttype extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Defines if there should be a way to uninstall the plugin via the administration UI.
+     *
+     * @return bool
+     */
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Get the name for the settings section.
+     *
+     * @return string
+     */
+    public function get_settings_section_name() {
+        return 'contentbanksetting' . $this->name;
+    }
+
+    /**
+     * Load the global settings for a particular contentbank plugin (if there are any)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php
+        $contenttype = $this; // Also to be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            $settings = new \admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return \moodle_url
+     */
+    public static function get_manage_url() {
+        return new \moodle_url('/admin/settings.php', array('section' => 'managecontentbanktypes'));
+    }
+
+
+    /**
+     * Gathers and returns the information about all plugins of the given type
+     *
+     * @param string $type the name of the plugintype, eg. mod, auth or workshopform
+     * @param string $typerootdir full path to the location of the plugin dir
+     * @param string $typeclass the name of the actually called class
+     * @param \core_plugin_manager $pluginman the plugin manager calling this method
+     * @return array of plugintype classes, indexed by the plugin name
+     */
+    public static function get_plugins($type, $typerootdir, $typeclass, $pluginman) {
+        global $CFG;
+
+        $contents = parent::get_plugins($type, $typerootdir, $typeclass, $pluginman);
+        if (!empty($CFG->contentbank_plugins_sortorder)) {
+            $order = explode(',', $CFG->contentbank_plugins_sortorder);
+            $order = array_merge(array_intersect($order, array_keys($contents)),
+                array_diff(array_keys($contents), $order));
+        } else {
+            $order = array_keys($contents);
+        }
+        $sortedcontents = array();
+        foreach ($order as $contentname) {
+            $sortedcontents[$contentname] = $contents[$contentname];
+        }
+        return $sortedcontents;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        $plugins = \core_plugin_manager::instance()->get_installed_plugins('contenttype');
+
+        if (!$plugins) {
+            return array();
+        }
+
+        $plugins = array_keys($plugins);
+        // Order the plugins.
+        if (!empty($CFG->contentbank_plugins_sortorder)) {
+            $order = explode(',', $CFG->contentbank_plugins_sortorder);
+            $order = array_merge(array_intersect($order, $plugins),
+                array_diff($plugins, $order));
+        } else {
+            $order = $plugins;
+        }
+
+        // Filter to return only enabled plugins.
+        $enabled = array();
+        foreach ($order as $plugin) {
+            $disabled = get_config('contentbank_' . $plugin, 'disabled');
+            if (empty($disabled)) {
+                $enabled[$plugin] = $plugin;
+            }
+        }
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $plugin = 'contentbank_' . $pluginname;
+        $oldvalue = get_config($plugin, 'disabled');
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            set_config('disabled', $disabled, $plugin);
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config('disabled', $plugin);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('disabled', $oldvalue, $disabled, $plugin);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Optional extra warning before uninstallation adding number of existing contenttype contents.
+     *
+     * @return string
+     */
+    public function get_uninstall_extra_warning() {
+        global $DB;
+
+        $contentcount = $DB->count_records('contentbank_content', ['contenttype' => "contenttype_$this->name"]);
+        if (!$contentcount) {
+            return '';
+        }
+
+        $message = get_string('contenttypeuninstalling',
+            'core_admin',
+            (object)['count' => $contentcount, 'type' => $this->displayname]
+        );
+
+        return $message;
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     */
+    public function uninstall_cleanup() {
+        global $DB;
+
+        $records = $DB->get_records('contentbank_content', ['contenttype' => 'contenttype_'.$this->name]);
+        $contenttypename = 'contenttype_'.$this->name;
+        $contenttypeclass = "\\$contenttypename\\contenttype";
+        foreach ($records as $record) {
+            $context = \context::instance_by_id($record->contextid, MUST_EXIST);
+            $contenttype = new $contenttypeclass($context);
+            $contentclass = "\\$contenttypename\\content";
+            $content = new $contentclass($record);
+            $contenttype->delete_content($content);
+        }
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/coursereport.php

@@ -0,0 +1,36 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class coursereport extends base {
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+}

lib/classes/plugininfo/customfield.php

@@ -0,0 +1,161 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2018 Toni Barbera {@link http://www.moodle.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+
+/**
+ * Class for admin tool plugins
+ *
+ * @package    core
+ * @copyright  2018 Toni Barbera {@link http://www.moodle.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class customfield extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Allow uninstall
+     * @return bool
+     */
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/settings.php', array('section' => 'managecustomfields'));
+    }
+
+    /**
+     * Enabled plugins
+     * @return array|null
+     */
+    public static function get_enabled_plugins() {
+        global $DB;
+
+        // Get all available plugins.
+        $plugins = \core_plugin_manager::instance()->get_installed_plugins('customfield');
+        if (!$plugins) {
+            return array();
+        }
+
+        // Check they are enabled using get_config (which is cached and hopefully fast).
+        $enabled = array();
+        foreach ($plugins as $plugin => $version) {
+            $disabled = get_config('customfield_' . $plugin, 'disabled');
+            if (empty($disabled)) {
+                $enabled[$plugin] = $plugin;
+            }
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $plugin = 'customfield_' . $pluginname;
+        $oldvalue = get_config($plugin, 'disabled');
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            set_config('disabled', $disabled, $plugin);
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config('disabled', $plugin);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('disabled', $oldvalue, $disabled, $plugin);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     */
+    public function uninstall_cleanup() {
+        global $DB;
+        $DB->delete_records_select('customfield_data',
+            'fieldid IN (SELECT f.id FROM {customfield_field} f WHERE f.type = ?)', [$this->name]);
+        $DB->delete_records('customfield_field', ['type' => $this->name]);
+        parent::uninstall_cleanup();
+    }
+
+    /**
+     * Setting section name
+     *
+     * @return null|string
+     */
+    public function get_settings_section_name() {
+        return 'customfieldsetting' . $this->name;
+    }
+
+    /**
+     * Load the global settings for a particular availability plugin (if there are any)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php
+        $availability = $this; // Also to be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig or !file_exists($this->full_path('settings.php'))) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+        include($this->full_path('settings.php')); // This may also set $settings to null.
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+}

lib/classes/plugininfo/dataformat.php

@@ -0,0 +1,205 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU Public License
+ * @copyright  2016 Brendan Heywood (brendan@catalyst-au.net)
+ * @package    core
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use core_plugin_manager;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for dataformats
+ *
+ * @package    core
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU Public License
+ * @copyright  2016 Brendan Heywood (brendan@catalyst-au.net)
+ */
+class dataformat extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Display name
+     */
+    public function init_display_name() {
+        if (!get_string_manager()->string_exists('dataformat', $this->component)) {
+            $this->displayname = '[dataformat,' . $this->component . ']';
+        } else {
+            $this->displayname = get_string('dataformat', $this->component);
+        }
+    }
+
+    /**
+     * Given a list of dataformat types, return them sorted according to site configuration (if set)
+     *
+     * @param string[] $formats List of formats, ['csv', 'pdf', etc]
+     * @return string[] List of formats according to configured sort, ['csv', 'odf', etc]
+     */
+    private static function get_plugins_sortorder(array $formats): array {
+        global $CFG;
+
+        if (!empty($CFG->dataformat_plugins_sortorder)) {
+            $order = explode(',', $CFG->dataformat_plugins_sortorder);
+            $order = array_merge(array_intersect($order, $formats), array_diff($formats, $order));
+        } else {
+            $order = $formats;
+        }
+
+        return $order;
+    }
+
+    /**
+     * Gathers and returns the information about all plugins of the given type
+     *
+     * @param string $type the name of the plugintype, eg. mod, auth or workshopform
+     * @param string $typerootdir full path to the location of the plugin dir
+     * @param string $typeclass the name of the actually called class
+     * @param core_plugin_manager $pluginman the plugin manager calling this method
+     * @return array of plugintype classes, indexed by the plugin name
+     */
+    public static function get_plugins($type, $typerootdir, $typeclass, $pluginman) {
+        $formats = parent::get_plugins($type, $typerootdir, $typeclass, $pluginman);
+
+        $order = static::get_plugins_sortorder(array_keys($formats));
+        $sortedformats = array();
+        foreach ($order as $formatname) {
+            $sortedformats[$formatname] = $formats[$formatname];
+        }
+        return $sortedformats;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        $plugins = core_plugin_manager::instance()->get_installed_plugins('dataformat');
+        if (!$plugins) {
+            return array();
+        }
+
+        $order = static::get_plugins_sortorder(array_keys($plugins));
+        $enabled = array();
+        foreach ($order as $formatname) {
+            $disabled = get_config('dataformat_' . $formatname, 'disabled');
+            if (empty($disabled)) {
+                $enabled[$formatname] = $formatname;
+            }
+        }
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $plugin = 'dataformat_' . $pluginname;
+        $oldvalue = get_config($plugin, 'disabled');
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            set_config('disabled', $disabled, $plugin);
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config('disabled', $plugin);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('disabled', $oldvalue, $disabled, $plugin);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Returns the node name used in admin settings menu for this plugin settings (if applicable)
+     *
+     * @return null|string node name or null if plugin does not create settings node (default)
+     */
+    public function get_settings_section_name() {
+        return 'dataformatsetting' . $this->name;
+    }
+
+    /**
+     * Loads plugin settings to the settings tree
+     *
+     * This function usually includes settings.php file in plugins folder.
+     * Alternatively it can create a link to some settings page (instance of admin_externalpage)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig whether the current user has moodle/site:config capability
+     */
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $dataformat = $this;     // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+        if (file_exists($this->full_path('settings.php'))) {
+            $fullpath = $this->full_path('settings.php');
+        } else if (file_exists($this->full_path('dataformatsettings.php'))) {
+            $fullpath = $this->full_path('dataformatsettings.php');
+        } else {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+        include($fullpath); // This may also set $settings to null.
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * dataformats can be uninstalled
+     *
+     * @return bool
+     */
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/settings.php?section=managedataformats');
+    }
+
+}

lib/classes/plugininfo/editor.php

@@ -0,0 +1,213 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for HTML editors
+ */
+class editor extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        if (empty($CFG->texteditors)) {
+            return array('atto'=>'atto', 'tinymce'=>'tinymce', 'textarea'=>'textarea');
+        }
+
+        $enabled = array();
+        foreach (explode(',', $CFG->texteditors) as $editor) {
+            $enabled[$editor] = $editor;
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+
+        $haschanged = false;
+        if (!empty($CFG->texteditors)) {
+            $plugins = array_flip(explode(',', $CFG->texteditors));
+        } else {
+            $plugins = [];
+        }
+
+        // Only set visibility if it's different from the current value.
+        if ($enabled && !array_key_exists($pluginname, $plugins)) {
+            $plugins[$pluginname] = $pluginname;
+            $haschanged = true;
+        } else if (!$enabled && array_key_exists($pluginname, $plugins)) {
+            unset($plugins[$pluginname]);
+            $haschanged = true;
+        }
+
+        // At least one editor must be active.
+        if (empty($plugins)) {
+            $plugins['textarea'] = 'textarea';
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            $new = implode(',', array_flip($plugins));
+            add_to_config_log('editor_visibility', !$enabled, $enabled, $pluginname);
+            set_config('texteditors', $new);
+            // Reset caches.
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    public function get_settings_section_name() {
+        return 'editorsettings' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $editor = $this;     // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig or !file_exists($this->full_path('settings.php'))) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+        include($this->full_path('settings.php')); // This may also set $settings to null.
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Basic textarea editor can not be uninstalled.
+     */
+    public function is_uninstall_allowed() {
+        if ($this->name === 'textarea') {
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/settings.php', array('section'=>'manageeditors'));
+    }
+
+    public static function plugintype_supports_ordering(): bool {
+        return true;
+    }
+
+    public static function get_sorted_plugins(bool $enabledonly = false): ?array {
+        global $CFG;
+
+        $pluginmanager = \core_plugin_manager::instance();
+        $plugins = $pluginmanager->get_plugins_of_type('editor');
+
+        // The Editor list is stored in an ordered string.
+        $activeeditors = explode(',', $CFG->texteditors);
+
+        $sortedplugins = [];
+        foreach ($activeeditors as $editor) {
+            if (isset($plugins[$editor])) {
+                $sortedplugins[$editor] = $plugins[$editor];
+                unset($plugins[$editor]);
+            }
+        }
+
+        if ($enabledonly) {
+            return $sortedplugins;
+        }
+
+        // Sort the rest of the plugins lexically.
+        uasort($plugins, function ($a, $b) {
+            return strnatcasecmp($a->name, $b->name);
+        });
+
+        return array_merge(
+            $sortedplugins,
+            $plugins,
+        );
+    }
+
+    public static function change_plugin_order(string $pluginname, int $direction): bool {
+        $activeeditors = array_keys(self::get_sorted_plugins(true));
+        $key = array_search($pluginname, $activeeditors);
+
+        if ($key === false) {
+            return false;
+        }
+
+        if ($direction === self::MOVE_DOWN) {
+            // Move down the list.
+            if ($key < (count($activeeditors) - 1)) {
+                $fsave = $activeeditors[$key];
+                $activeeditors[$key] = $activeeditors[$key + 1];
+                $activeeditors[$key + 1] = $fsave;
+                add_to_config_log('editor_position', $key, $key + 1, $pluginname);
+                set_config('texteditors', implode(',', $activeeditors));
+                \core_plugin_manager::reset_caches();
+
+                return true;
+            }
+        } else if ($direction === self::MOVE_UP) {
+            if ($key >= 1) {
+                $fsave = $activeeditors[$key];
+                $activeeditors[$key] = $activeeditors[$key - 1];
+                $activeeditors[$key - 1] = $fsave;
+                add_to_config_log('editor_position', $key, $key - 1, $pluginname);
+                set_config('texteditors', implode(',', $activeeditors));
+                \core_plugin_manager::reset_caches();
+
+                return true;
+            }
+        }
+
+        return false;
+    }
+}

lib/classes/plugininfo/enrol.php

@@ -0,0 +1,199 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for enrolment plugins
+ */
+class enrol extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     *
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        $enabled = array();
+        foreach (explode(',', $CFG->enrol_plugins_enabled) as $enrol) {
+            $enabled[$enrol] = $enrol;
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+
+        $haschanged = false;
+        $plugins = [];
+        if (!empty($CFG->enrol_plugins_enabled)) {
+            $plugins = array_flip(explode(',', $CFG->enrol_plugins_enabled));
+        }
+        // Only set visibility if it's different from the current value.
+        if ($enabled && !array_key_exists($pluginname, $plugins)) {
+            $plugins[$pluginname] = $pluginname;
+            $haschanged = true;
+        } else if (!$enabled && array_key_exists($pluginname, $plugins)) {
+            unset($plugins[$pluginname]);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            $new = implode(',', array_flip($plugins));
+            add_to_config_log('enrol_plugins_enabled', !$enabled, $enabled, $pluginname);
+            set_config('enrol_plugins_enabled', $new);
+            // Reset caches.
+            \core_plugin_manager::reset_caches();
+            // Resets all enrol caches.
+            $syscontext = \context_system::instance();
+            $syscontext->mark_dirty();
+        }
+
+        return $haschanged;
+    }
+
+    public function get_settings_section_name() {
+        if (file_exists($this->full_path('settings.php'))) {
+            return 'enrolsettings' . $this->name;
+        } else {
+            return null;
+        }
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $enrol = $this;      // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig or !file_exists($this->full_path('settings.php'))) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+
+        include($this->full_path('settings.php')); // This may also set $settings to null!
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    public function is_uninstall_allowed() {
+        if ($this->name === 'manual') {
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/settings.php', array('section'=>'manageenrols'));
+    }
+
+    /**
+     * Return warning with number of activities and number of affected courses.
+     *
+     * @return string
+     */
+    public function get_uninstall_extra_warning() {
+        global $DB, $OUTPUT;
+
+        $sql = "SELECT COUNT('x')
+                  FROM {user_enrolments} ue
+                  JOIN {enrol} e ON e.id = ue.enrolid
+                 WHERE e.enrol = :plugin";
+        $count = $DB->count_records_sql($sql, array('plugin'=>$this->name));
+
+        if (!$count) {
+            return '';
+        }
+
+        $migrateurl = new moodle_url('/admin/enrol.php', array('action'=>'migrate', 'enrol'=>$this->name, 'sesskey'=>sesskey()));
+        $migrate = new \single_button($migrateurl, get_string('migratetomanual', 'core_enrol'));
+        $button = $OUTPUT->render($migrate);
+
+        $result = '<p>'.get_string('uninstallextraconfirmenrol', 'core_plugin', array('enrolments'=>$count)).'</p>';
+        $result .= $button;
+
+        return $result;
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        global $DB, $CFG;
+
+        // NOTE: this is a bit brute force way - it will not trigger events and hooks properly.
+
+        // Nuke all role assignments.
+        role_unassign_all(array('component'=>'enrol_'.$this->name));
+
+        // Purge participants.
+        $DB->delete_records_select('user_enrolments', "enrolid IN (SELECT id FROM {enrol} WHERE enrol = ?)", array($this->name));
+
+        // Purge enrol instances.
+        $DB->delete_records('enrol', array('enrol'=>$this->name));
+
+        // Tweak enrol settings.
+        if (!empty($CFG->enrol_plugins_enabled)) {
+            $enabledenrols = explode(',', $CFG->enrol_plugins_enabled);
+            $enabledenrols = array_unique($enabledenrols);
+            $enabledenrols = array_flip($enabledenrols);
+            unset($enabledenrols[$this->name]);
+            $enabledenrols = array_flip($enabledenrols);
+            if (is_array($enabledenrols)) {
+                set_config('enrol_plugins_enabled', implode(',', $enabledenrols));
+            }
+        }
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/fileconverter.php

@@ -0,0 +1,193 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2017 Damyon Wiese
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+/**
+ * Class for document converter plugins
+ *
+ * @package    core
+ * @copyright  2017 Damyon Wiese
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class fileconverter extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Should there be a way to uninstall the plugin via the administration UI.
+     *
+     * Uninstallation is allowed for fileconverter plugins.
+     *
+     * @return bool
+     */
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Get the name for the settings section.
+     *
+     * @return string
+     */
+    public function get_settings_section_name() {
+        return 'fileconverter' . $this->name;
+    }
+
+    /**
+     * Load the global settings for a particular availability plugin (if there are any)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            $settings = new \admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return \moodle_url
+     */
+    public static function get_manage_url() {
+        return new \moodle_url('/admin/settings.php', array('section' => 'managefileconverterplugins'));
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     *
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        $order = (!empty($CFG->converter_plugins_sortorder)) ? explode(',', $CFG->converter_plugins_sortorder) : [];
+        if ($order) {
+            $plugins = \core_plugin_manager::instance()->get_installed_plugins('fileconverter');
+            $order = array_intersect($order, array_keys($plugins));
+        }
+
+        return array_combine($order, $order);
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+
+        $haschanged = false;
+        $plugins = [];
+        if (!empty($CFG->converter_plugins_sortorder)) {
+            $plugins = array_flip(explode(',', $CFG->converter_plugins_sortorder));
+        }
+        // Only set visibility if it's different from the current value.
+        if ($enabled && !array_key_exists($pluginname, $plugins)) {
+            $plugins[$pluginname] = $pluginname;
+            $haschanged = true;
+        } else if (!$enabled && array_key_exists($pluginname, $plugins)) {
+            unset($plugins[$pluginname]);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('converter_plugins_sortorder', !$enabled, $enabled, $pluginname);
+            self::set_enabled_plugins(array_flip($plugins));
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Sets the current plugin as enabled or disabled
+     * When enabling tries to guess the sortorder based on default rank returned by the plugin.
+     * @param bool $newstate
+     */
+    public function set_enabled($newstate = true) {
+        self::enable_plugin($this->name, $newstate);
+    }
+
+    /**
+     * Set the list of enabled converter players in the specified sort order
+     * To be used when changing settings or in unit tests
+     * @param string|array $list list of plugin names without frankenstyle prefix - comma-separated string or an array
+     */
+    public static function set_enabled_plugins($list) {
+        if (empty($list)) {
+            $list = [];
+        } else if (!is_array($list)) {
+            $list = explode(',', $list);
+        }
+        if ($list) {
+            $plugins = \core_plugin_manager::instance()->get_installed_plugins('fileconverter');
+            $list = array_intersect($list, array_keys($plugins));
+        }
+        set_config('converter_plugins_sortorder', join(',', $list));
+        \core_plugin_manager::reset_caches();
+    }
+
+    /**
+     * Returns a string describing the formats this engine can converter from / to.
+     *
+     * @return string
+     */
+    public function get_supported_conversions() {
+        $classname = self::get_classname($this->name);
+        if (class_exists($classname)) {
+            $object = new $classname();
+            return $object->get_supported_conversions();
+        }
+        return '';
+    }
+
+    /**
+     * Return the class name for the plugin.
+     *
+     * @param   string $plugin
+     * @return  string
+     */
+    public static function get_classname($plugin) {
+        return "\\fileconverter_{$plugin}\\converter";
+    }
+}

lib/classes/plugininfo/filter.php

@@ -0,0 +1,187 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for text filters
+ */
+class filter extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    public function init_display_name() {
+        if (!get_string_manager()->string_exists('filtername', $this->component)) {
+            $this->displayname = '[filtername,' . $this->component . ']';
+        } else {
+            $this->displayname = get_string('filtername', $this->component);
+        }
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $DB, $CFG;
+        require_once("$CFG->libdir/filterlib.php");
+
+        $enabled = array();
+        $filters = $DB->get_records_select('filter_active', "active <> :disabled AND contextid = :contextid", array(
+            'disabled' => TEXTFILTER_DISABLED, 'contextid' => \context_system::instance()->id), 'filter ASC', 'id, filter');
+        foreach ($filters as $filter) {
+            $enabled[$filter->filter] = $filter->filter;
+        }
+
+        return $enabled;
+    }
+
+    /**
+     * Enable or disable a plugin.
+     * When possible, the change will be stored into the config_log table, to let admins check when/who has modified it.
+     *
+     * @param string $pluginname The plugin name to enable/disable.
+     * @param int $enabled Whether the pluginname should be TEXTFILTER_ON, TEXTFILTER_OFF or TEXTFILTER_DISABLED.
+     *
+     * @return bool It always return true because we don't know if the value has changed or not. That way, we guarantee any action
+     * required if it's changed will be executed.
+     */
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+        require_once("$CFG->libdir/filterlib.php");
+        require_once("$CFG->libdir/weblib.php");
+
+        filter_set_global_state($pluginname, $enabled);
+        if ($enabled == TEXTFILTER_DISABLED) {
+            filter_set_applies_to_strings($pluginname, false);
+        }
+
+        reset_text_filters_cache();
+        \core_plugin_manager::reset_caches();
+
+        return true;
+    }
+
+    /**
+     * Returns current status for a pluginname.
+     *
+     * Filters have different values for enabled/disabled plugins so the current value needs to be calculated in a
+     * different way than the default method in the base class.
+     *
+     * @param string $pluginname The plugin name to check.
+     * @return int The current status (enabled, disabled...) of $pluginname.
+     */
+    public static function get_enabled_plugin(string $pluginname): int {
+        global $DB, $CFG;
+        require_once("$CFG->libdir/filterlib.php");
+
+        $conditions = ['filter' => $pluginname, 'contextid' => \context_system::instance()->id];
+        $record = $DB->get_record('filter_active', $conditions, 'active');
+
+        return $record ? (int) $record->active : TEXTFILTER_DISABLED;
+    }
+
+    public function get_settings_section_name() {
+        return 'filtersetting' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $filter = $this;     // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+        if (file_exists($this->full_path('settings.php'))) {
+            $fullpath = $this->full_path('settings.php');
+        } else if (file_exists($this->full_path('filtersettings.php'))) {
+            $fullpath = $this->full_path('filtersettings.php');
+        } else {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+        include($fullpath); // This may also set $settings to null.
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/filters.php');
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        global $DB, $CFG;
+
+        $DB->delete_records('filter_active', array('filter' => $this->name));
+        $DB->delete_records('filter_config', array('filter' => $this->name));
+
+        if (empty($CFG->filterall)) {
+            $stringfilters = array();
+        } else if (!empty($CFG->stringfilters)) {
+            $stringfilters = explode(',', $CFG->stringfilters);
+            $stringfilters = array_combine($stringfilters, $stringfilters);
+        } else {
+            $stringfilters = array();
+        }
+
+        unset($stringfilters[$this->name]);
+
+        set_config('stringfilters', implode(',', $stringfilters));
+        set_config('filterall', !empty($stringfilters));
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/format.php

@@ -0,0 +1,203 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url, part_of_admin_tree, admin_settingpage, core_plugin_manager;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for course formats
+ */
+class format extends base {
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $DB;
+
+        $plugins = core_plugin_manager::instance()->get_installed_plugins('format');
+        if (!$plugins) {
+            return array();
+        }
+        $installed = array();
+        foreach ($plugins as $plugin => $version) {
+            $installed[] = 'format_'.$plugin;
+        }
+
+        list($installed, $params) = $DB->get_in_or_equal($installed, SQL_PARAMS_NAMED);
+        $disabled = $DB->get_records_select('config_plugins', "plugin $installed AND name = 'disabled'", $params, 'plugin ASC');
+        foreach ($disabled as $conf) {
+            if (empty($conf->value)) {
+                continue;
+            }
+            list($type, $name) = explode('_', $conf->plugin, 2);
+            unset($plugins[$name]);
+        }
+
+        $enabled = array();
+        foreach ($plugins as $plugin => $version) {
+            $enabled[$plugin] = $plugin;
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $plugin = 'format_' . $pluginname;
+        $oldvalue = get_config($plugin, 'disabled');
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            if (get_config('moodlecourse', 'format') === $pluginname) {
+                // The default course format can't be disabled.
+                throw new \moodle_exception('cannotdisableformat', 'error');
+            }
+            set_config('disabled', $disabled, $plugin);
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config('disabled', $plugin);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('disabled', $oldvalue, $disabled, $plugin);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Gathers and returns the information about all plugins of the given type
+     *
+     * @param string $type the name of the plugintype, eg. mod, auth or workshopform
+     * @param string $typerootdir full path to the location of the plugin dir
+     * @param string $typeclass the name of the actually called class
+     * @param core_plugin_manager $pluginman the plugin manager calling this method
+     * @return array of plugintype classes, indexed by the plugin name
+     */
+    public static function get_plugins($type, $typerootdir, $typeclass, $pluginman) {
+        global $CFG;
+        require_once($CFG->dirroot.'/course/lib.php');
+
+        $formats = parent::get_plugins($type, $typerootdir, $typeclass, $pluginman);
+        $order = get_sorted_course_formats();
+        $sortedformats = array();
+        foreach ($order as $formatname) {
+            $sortedformats[$formatname] = $formats[$formatname];
+        }
+        return $sortedformats;
+    }
+
+    public function get_settings_section_name() {
+        return 'formatsetting' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig or !file_exists($this->full_path('settings.php'))) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+        include($this->full_path('settings.php')); // This may also set $settings to null.
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    public function is_uninstall_allowed() {
+        if ($this->name !== get_config('moodlecourse', 'format') && $this->name !== 'site') {
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/settings.php', array('section'=>'manageformats'));
+    }
+
+    public function get_uninstall_extra_warning() {
+        global $DB;
+
+        $coursecount = $DB->count_records('course', array('format' => $this->name));
+
+        if (!$coursecount) {
+            return '';
+        }
+
+        $defaultformat = $this->pluginman->plugin_name('format_'.get_config('moodlecourse', 'format'));
+        $message = get_string(
+            'formatuninstallwithcourses', 'core_admin',
+            (object)array('count' => $coursecount, 'format' => $this->displayname,
+                'defaultformat' => $defaultformat));
+
+        return $message;
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        global $DB;
+
+        if (($defaultformat = get_config('moodlecourse', 'format')) && $defaultformat !== $this->name) {
+            $courses = $DB->get_records('course', array('format' => $this->name), 'id');
+            $data = (object)array('id' => null, 'format' => $defaultformat);
+            foreach ($courses as $record) {
+                $data->id = $record->id;
+                update_course($data);
+            }
+        }
+
+        $DB->delete_records('course_format_options', array('format' => $this->name));
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/general.php

@@ -0,0 +1,36 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+
+/**
+ * General class for all plugin types that do not have their own class
+ */
+class general extends base {
+    public function is_uninstall_allowed() {
+        return false;
+    }
+}

lib/classes/plugininfo/gradeexport.php

@@ -0,0 +1,36 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class gradeexport extends base {
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+}

lib/classes/plugininfo/gradeimport.php

@@ -0,0 +1,36 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class gradeimport extends base {
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+}

lib/classes/plugininfo/gradereport.php

@@ -0,0 +1,36 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class gradereport extends base {
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+}

lib/classes/plugininfo/gradingform.php

@@ -0,0 +1,60 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class gradingform extends base {
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Pre-uninstall hook.
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     */
+    public function uninstall_cleanup() {
+        global $DB;
+
+        // Find all definitions and templates.
+        $definitions = $DB->get_fieldset_select('grading_definitions', 'id', 'method = ?', [$this->name]);
+        if ($definitions) {
+            // Delete instances and definitions. Deleting instance will not delete grades because they were
+            // already pushed to the module and gradebook.
+            list($sqld, $paramsd) = $DB->get_in_or_equal($definitions);
+            $DB->delete_records_select('grading_instances', 'definitionid ' . $sqld, $paramsd);
+            $DB->delete_records_select('grading_definitions', 'id ' . $sqld, $paramsd);
+        }
+        // Delete templates for this grading method.
+        $DB->delete_records_select('grading_areas', 'component = ? AND activemethod = ?', array('core_grading', $this->name));
+        // Update the remaining grading areas to use simple grading method instead of this grading method.
+        $DB->execute('UPDATE {grading_areas} SET activemethod = NULL WHERE activemethod = ?', [$this->name]);
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/h5plib.php

@@ -0,0 +1,88 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2019 Andrew Nicols <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for H5P libraries.
+ */
+class h5plib extends base {
+
+    /**
+     * Defines if there should be a way to uninstall the plugin via the administration UI.
+     *
+     * @return bool
+     */
+    public function is_uninstall_allowed(): bool {
+        return true;
+    }
+
+    /**
+     * H5P versions cannot be disabled.
+     *
+     * @return boolean
+     */
+    public function is_enabled(): bool {
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url(): \moodle_url {
+        return new moodle_url('/admin/settings.php', ['section' => 'h5psettings']);
+    }
+
+    /**
+     * Loads plugin settings to the settings tree
+     *
+     * This function usually includes settings.php file in plugins folder.
+     * Alternatively it can create a link to some settings page (instance of admin_externalpage)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig whether the current user has moodle/site:config capability
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        if (file_exists($this->full_path('settings.php'))) {
+            include($this->full_path('settings.php'));
+        }
+    }
+}

lib/classes/plugininfo/local.php

@@ -0,0 +1,70 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for local plugins
+ */
+class local extends base {
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/localplugins.php');
+    }
+
+    /**
+     * Loads plugin settings to the settings tree
+     *
+     * This function usually includes settings.php file in plugins folder.
+     * Alternatively it can create a link to some settings page (instance of admin_externalpage)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig whether the current user has moodle/site:config capability
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (file_exists($this->full_path('settings.php'))) {
+            include($this->full_path('settings.php'));
+        }
+    }
+}

lib/classes/plugininfo/media.php

@@ -0,0 +1,271 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2016 Marina Glancy
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+/**
+ * Class for media plugins
+ *
+ * @package    core
+ * @copyright  2016 Marina Glancy
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class media extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Get the name for the settings section.
+     *
+     * @return string
+     */
+    public function get_settings_section_name() {
+        return 'mediasetting' . $this->name;
+    }
+
+    /**
+     * Load the global settings for a particular availability plugin (if there are any)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php
+        $availability = $this; // Also to be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            $settings = new \admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return \moodle_url
+     */
+    public static function get_manage_url() {
+        return new \moodle_url('/admin/settings.php', array('section' => 'managemediaplayers'));
+    }
+
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        $order = (!empty($CFG->media_plugins_sortorder)) ? explode(',', $CFG->media_plugins_sortorder) : [];
+        if ($order) {
+            $plugins = \core_plugin_manager::instance()->get_installed_plugins('media');
+            $order = array_intersect($order, array_keys($plugins));
+        }
+        return array_combine($order, $order);
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+
+        $haschanged = false;
+        $plugins = [];
+        if (!empty($CFG->media_plugins_sortorder)) {
+            $plugins = explode(',', $CFG->media_plugins_sortorder);
+        }
+        // Only set visibility if it's different from the current value.
+        if ($enabled && !in_array($pluginname, $plugins)) {
+            // Enable media plugin.
+
+            /** @var \core\plugininfo\media[] $pluginsbytype */
+            $pluginsbytype = \core_plugin_manager::instance()->get_plugins_of_type('media');
+            if (!array_key_exists($pluginname, $pluginsbytype)) {
+                // Can not be enabled.
+                return false;
+            }
+
+            $rank = $pluginsbytype[$pluginname]->get_rank();
+            $position = 0;
+            // Insert before the first enabled plugin which default rank is smaller than the default rank of this one.
+            foreach ($plugins as $playername) {
+                if (($player = $pluginsbytype[$playername]) && ($rank > $player->get_rank())) {
+                    break;
+                }
+                $position++;
+            }
+            array_splice($plugins, $position, 0, [$pluginname]);
+            $haschanged = true;
+        } else if (!$enabled && in_array($pluginname, $plugins)) {
+            // Disable media plugin.
+            $key = array_search($pluginname, $plugins);
+            unset($plugins[$key]);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('media_plugins_sortorder', !$enabled, $enabled, $pluginname);
+            self::set_enabled_plugins($plugins);
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Sets the current plugin as enabled or disabled
+     * When enabling tries to guess the sortorder based on default rank returned by the plugin.
+     * @param bool $newstate
+     */
+    public function set_enabled($newstate = true) {
+        self::enable_plugin($this->name, $newstate);
+    }
+
+    /**
+     * Set the list of enabled media players in the specified sort order
+     * To be used when changing settings or in unit tests
+     * @param string|array $list list of plugin names without frankenstyle prefix - comma-separated string or an array
+     */
+    public static function set_enabled_plugins($list) {
+        if (empty($list)) {
+            $list = [];
+        } else if (!is_array($list)) {
+            $list = explode(',', $list);
+        }
+        if ($list) {
+            $plugins = \core_plugin_manager::instance()->get_installed_plugins('media');
+            $list = array_intersect($list, array_keys($plugins));
+        }
+        set_config('media_plugins_sortorder', join(',', $list));
+        \core_plugin_manager::reset_caches();
+        \core_media_manager::reset_caches();
+    }
+
+    /**
+     * Returns the default rank of this plugin for default sort order
+     * @return int
+     */
+    public function get_rank() {
+        $classname = '\media_'.$this->name.'_plugin';
+        if (class_exists($classname)) {
+            $object = new $classname();
+            return $object->get_rank();
+        }
+        return 0;
+    }
+
+    /**
+     * Returns human-readable string of supported file/link types for the "Manage media players" page
+     * @param array $extensions
+     * @return string
+     */
+    public function supports(&$extensions) {
+        $classname = '\media_'.$this->name.'_plugin';
+        if (class_exists($classname)) {
+            $object = new $classname();
+            $result = $object->supports($extensions);
+            foreach ($object->get_supported_extensions() as $ext) {
+                $extensions[$ext] = $ext;
+            }
+            return $result;
+        }
+        return '';
+    }
+
+    public static function plugintype_supports_ordering(): bool {
+        return true;
+    }
+
+    // phpcs:ignore VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable
+    public static function get_sorted_plugins(bool $enabledonly = false): ?array {
+        $pluginmanager = \core_plugin_manager::instance();
+
+        $plugins = $pluginmanager->get_plugins_of_type('media');
+        $enabledplugins = $pluginmanager->get_enabled_plugins('media');
+
+        // Sort plugins so enabled plugins are displayed first and all others are displayed in the end sorted by rank.
+        \core_collator::asort_objects_by_method($plugins, 'get_rank', \core_collator::SORT_NUMERIC);
+
+        $order = array_values($enabledplugins);
+        if (!$enabledonly) {
+            $order = array_merge($order, array_diff(array_reverse(array_keys($plugins)), $order));
+        }
+
+        $sortedplugins = [];
+        foreach ($order as $name) {
+            $sortedplugins[$name] = $plugins[$name];
+        }
+
+        return $sortedplugins;
+    }
+
+    public static function change_plugin_order(string $pluginname, int $direction): bool {
+        $activeeditors = array_keys(self::get_sorted_plugins(true));
+        $key = array_search($pluginname, $activeeditors);
+        [$media] = explode('_', $pluginname, 2);
+
+        if ($key === false) {
+            return false;
+        }
+
+        $sortorder = array_values(self::get_enabled_plugins());
+
+        if ($direction === self::MOVE_DOWN) {
+            // Move down the list.
+            if ((($pos = array_search($media, $sortorder)) !== false) && ($pos < count($sortorder) - 1)) {
+                $tmp = $sortorder[$pos + 1];
+                $sortorder[$pos + 1] = $sortorder[$pos];
+                $sortorder[$pos] = $tmp;
+                self::set_enabled_plugins($sortorder);
+
+                return true;
+            }
+        } else if ($direction === self::MOVE_UP) {
+            if (($pos = array_search($media, $sortorder)) > 0) {
+                $tmp = $sortorder[$pos - 1];
+                $sortorder[$pos - 1] = $sortorder[$pos];
+                $sortorder[$pos] = $tmp;
+                self::set_enabled_plugins($sortorder);
+
+                return true;
+            }
+        }
+
+        return false;
+    }
+}

lib/classes/plugininfo/message.php

@@ -0,0 +1,134 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for messaging processors
+ */
+class message extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $DB;
+        return $DB->get_records_menu('message_processors', array('enabled'=>1), 'name ASC', 'name, name AS val');
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $DB;
+
+        if (!$plugin = $DB->get_record('message_processors', ['name' => $pluginname])) {
+            throw new \moodle_exception('invalidplugin', 'message', '', $pluginname);
+        }
+
+        $haschanged = false;
+
+        // Only set visibility if it's different from the current value.
+        if ($plugin->enabled != $enabled) {
+            $haschanged = true;
+            $processor = \core_message\api::get_processed_processor_object($plugin);
+
+            // Include this information into config changes table.
+            add_to_config_log($processor->name, $processor->enabled, $enabled, 'core');
+
+            // Save processor enabled/disabled status.
+            \core_message\api::update_processor_status($processor, $enabled);
+        }
+
+        return $haschanged;
+    }
+
+    public function get_settings_section_name() {
+        return 'messagesetting' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        $processors = get_message_processors();
+        if (isset($processors[$this->name])) {
+            $processor = $processors[$this->name];
+            if ($processor->available && $processor->hassettings) {
+                $settings = new admin_settingpage($section, $this->displayname,
+                    'moodle/site:config', $this->is_enabled() === false);
+                include($this->full_path('settings.php')); // This may also set $settings to null.
+            }
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/message.php');
+    }
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        global $CFG;
+
+        require_once($CFG->libdir.'/messagelib.php');
+        message_processor_uninstall($this->name);
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/mlbackend.php

@@ -0,0 +1,89 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2017 David Monllao
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for analytics machine learning backend plugins
+ *
+ * @package    core
+ * @copyright  2017 David Monllao
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class mlbackend extends base {
+
+    /**
+     * Is uninstall allowed or not.
+     *
+     * @return bool
+     */
+    public function is_uninstall_allowed() {
+
+        return !\core_analytics\manager::is_mlbackend_used('mlbackend_' . $this->name);
+    }
+
+    /**
+     * Returns the node name used in admin settings menu for this plugin settings (if applicable).
+     *
+     * @return null|string node name or null if plugin does not create settings node (default)
+     */
+    public function get_settings_section_name() {
+        return 'mlbackendsettings' . $this->name;
+    }
+
+    /**
+     * Load the global settings for a particular availability plugin (if there are any)
+     *
+     * @param  \part_of_admin_tree $adminroot
+     * @param  string $parentnodename
+     * @param  bool $hassiteconfig
+     * @return void
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            $settings = new \admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+}

lib/classes/plugininfo/mnetservice.php

@@ -0,0 +1,42 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class representing an MNet service
+ */
+class mnetservice extends base {
+
+    public function is_enabled() {
+        global $CFG;
+
+        if (empty($CFG->mnet_dispatcher_mode) || $CFG->mnet_dispatcher_mode !== 'strict') {
+            return false;
+        } else {
+            return parent::is_enabled();
+        }
+    }
+}

lib/classes/plugininfo/mod.php

@@ -0,0 +1,269 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for activity modules
+ */
+class mod extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $DB;
+        return $DB->get_records_menu('modules', array('visible'=>1), 'name ASC', 'name, name AS val');
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $DB;
+
+        if (!$module = $DB->get_record('modules', ['name' => $pluginname])) {
+            throw new \moodle_exception('moduledoesnotexist', 'error');
+        }
+
+        $haschanged = false;
+
+        // Only set visibility if it's different from the current value.
+        if ($module->visible != $enabled) {
+            if ($enabled && component_callback_exists("mod_{$pluginname}", 'pre_enable_plugin_actions')) {
+                // This callback may be used to perform actions that must be completed prior to enabling a plugin.
+                // Example of this may include:
+                // - making a configuration change
+                // - adding an alert
+                // - checking a pre-requisite
+                //
+                // If the return value is falsy, then the change will be prevented.
+                if (!component_callback("mod_{$pluginname}", 'pre_enable_plugin_actions')) {
+                    return false;
+                }
+            }
+            // Set module visibility.
+            $DB->set_field('modules', 'visible', $enabled, ['id' => $module->id]);
+            $haschanged = true;
+
+            if ($enabled) {
+                // Revert the previous saved visible state for the course module.
+                $DB->set_field('course_modules', 'visible', '1', ['visibleold' => 1, 'module' => $module->id]);
+
+                // Increment course.cacherev for courses where we just made something visible.
+                // This will force cache rebuilding on the next request.
+                increment_revision_number('course', 'cacherev',
+                    "id IN (SELECT DISTINCT course
+                                       FROM {course_modules}
+                                      WHERE visible = 1 AND module = ?)",
+                    [$module->id]
+                );
+            } else {
+                // Remember the visibility status in visibleold and hide.
+                $sql = "UPDATE {course_modules}
+                           SET visibleold = visible, visible = 0
+                         WHERE module = ?";
+                $DB->execute($sql, [$module->id]);
+                // Increment course.cacherev for courses where we just made something invisible.
+                // This will force cache rebuilding on the next request.
+                increment_revision_number('course', 'cacherev',
+                    'id IN (SELECT DISTINCT course
+                                       FROM {course_modules}
+                                      WHERE visibleold = 1 AND module = ?)',
+                    [$module->id]
+                );
+            }
+
+            // Include this information into config changes table.
+            add_to_config_log('mod_visibility', $module->visible, $enabled, $pluginname);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Magic method getter, redirects to read only values.
+     *
+     * For module plugins we pretend the object has 'visible' property for compatibility
+     * with plugins developed for Moodle version below 2.4
+     *
+     * @param string $name
+     * @return mixed
+     */
+    public function __get($name) {
+        if ($name === 'visible') {
+            debugging('This is now an instance of plugininfo_mod, please use $module->is_enabled() instead of $module->visible', DEBUG_DEVELOPER);
+            return ($this->is_enabled() !== false);
+        }
+        return parent::__get($name);
+    }
+
+    public function init_display_name() {
+        if (get_string_manager()->string_exists('pluginname', $this->component)) {
+            $this->displayname = get_string('pluginname', $this->component);
+        } else {
+            $this->displayname = get_string('modulename', $this->component);
+        }
+    }
+
+    public function get_settings_section_name() {
+        return 'modsetting' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $module = $this;     // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig or !file_exists($this->full_path('settings.php'))) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+        include($this->full_path('settings.php')); // This may also set $settings to null.
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Allow all activity modules but Forum to be uninstalled.
+     *
+     * This exception for the Forum has been hard-coded in Moodle since ages,
+     * we may want to re-think it one day.
+     */
+    public function is_uninstall_allowed() {
+        if ($this->name === 'forum') {
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/modules.php');
+    }
+
+    /**
+     * Return warning with number of activities and number of affected courses.
+     *
+     * @return string
+     */
+    public function get_uninstall_extra_warning() {
+        global $DB;
+
+        if (!$module = $DB->get_record('modules', array('name'=>$this->name))) {
+            return '';
+        }
+
+        if (!$count = $DB->count_records('course_modules', array('module'=>$module->id))) {
+            return '';
+        }
+
+        $sql = "SELECT COUNT('x')
+                  FROM (
+                    SELECT course
+                      FROM {course_modules}
+                     WHERE module = :mid
+                  GROUP BY course
+                  ) c";
+        $courses = $DB->count_records_sql($sql, array('mid'=>$module->id));
+
+        return '<p>'.get_string('uninstallextraconfirmmod', 'core_plugin', array('instances'=>$count, 'courses'=>$courses)).'</p>';
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        global $DB, $CFG;
+
+        if (!$module = $DB->get_record('modules', array('name' => $this->name))) {
+            parent::uninstall_cleanup();
+            return;
+        }
+
+        // Delete all the relevant instances from all course sections.
+        if ($coursemods = $DB->get_records('course_modules', array('module' => $module->id))) {
+            foreach ($coursemods as $coursemod) {
+                // Do not verify results, there is not much we can do anyway.
+                delete_mod_from_section($coursemod->id, $coursemod->section);
+            }
+        }
+
+        // Increment course.cacherev for courses that used this module.
+        // This will force cache rebuilding on the next request.
+        increment_revision_number('course', 'cacherev',
+            "id IN (SELECT DISTINCT course
+                      FROM {course_modules}
+                     WHERE module=?)",
+            array($module->id));
+
+        // Delete all the course module records.
+        $DB->delete_records('course_modules', array('module' => $module->id));
+
+        // Delete module contexts.
+        if ($coursemods) {
+            foreach ($coursemods as $coursemod) {
+                \context_helper::delete_instance(CONTEXT_MODULE, $coursemod->id);
+            }
+        }
+
+        // Delete the module entry itself.
+        $DB->delete_records('modules', array('name' => $module->name));
+
+        // Cleanup the gradebook.
+        require_once($CFG->libdir.'/gradelib.php');
+        grade_uninstalled_module($module->name);
+
+        // Do not look for legacy $module->name . '_uninstall any more,
+        // they should have migrated to db/uninstall.php by now.
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/orphaned.php

@@ -0,0 +1,90 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines class used for orphaned subplugins.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+
+/**
+ * Orphaned subplugins class.
+ */
+class orphaned extends base {
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * We do not know if orphaned subplugins are enabled.
+     * @return bool
+     */
+    public function is_enabled() {
+        return null;
+    }
+
+    /**
+     * No lang strings are present.
+     */
+    public function init_display_name() {
+        $this->displayname = $this->component;
+    }
+
+    /**
+     * Oprhaned plugins can not be enabled.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        return null;
+    }
+
+    /**
+     * Gathers and returns the information about all plugins of the given type,
+     * either on disk or previously installed.
+     *
+     * @param string $type the name of the plugintype, eg. mod, auth or workshopform
+     * @param string $typerootdir full path to the location of the plugin dir
+     * @param string $typeclass the name of the actually called class
+     * @param \core_plugin_manager $pluginman the plugin manager calling this method
+     * @return array of plugintype classes, indexed by the plugin name
+     */
+    public static function get_plugins($type, $typerootdir, $typeclass, $pluginman) {
+        $return = array();
+        $plugins = $pluginman->get_installed_plugins($type);
+
+        foreach ($plugins as $name => $version) {
+            $plugin              = new $typeclass();
+            $plugin->type        = $type;
+            $plugin->typerootdir = $typerootdir;
+            $plugin->name        = $name;
+            $plugin->rootdir     = null;
+            $plugin->displayname = $name;
+            $plugin->versiondb   = $version;
+            $plugin->pluginman   = $pluginman;
+            $plugin->init_is_standard();
+
+            $return[$name] = $plugin;
+        }
+
+        return $return;
+    }
+}

lib/classes/plugininfo/paygw.php

@@ -0,0 +1,154 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Contains subplugin info class for payment gateways.
+ *
+ * @package   core_payment
+ * @copyright 2019 Shamim Rezaie <shamim@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core\plugininfo;
+
+/**
+ * Payment gateway subplugin info class.
+ *
+ * @copyright 2019 Shamim Rezaie <shamim@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class paygw extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    public function get_settings_section_name() {
+        return 'paymentgateway' . $this->name;
+    }
+
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            $settings = new \admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    public static function get_manage_url() {
+        return new \moodle_url('/admin/settings.php', array('section' => 'managepaymentgateways'));
+    }
+
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        $order = (!empty($CFG->paygw_plugins_sortorder)) ? explode(',', $CFG->paygw_plugins_sortorder) : [];
+        if ($order) {
+            $plugins = \core_plugin_manager::instance()->get_installed_plugins('paygw');
+            $order = array_intersect($order, array_keys($plugins));
+        }
+
+        return array_combine($order, $order);
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+
+        $haschanged = false;
+        $plugins = [];
+        if (!empty($CFG->paygw_plugins_sortorder)) {
+            $plugins = array_flip(explode(',', $CFG->paygw_plugins_sortorder));
+        }
+        // Only set visibility if it's different from the current value.
+        if ($enabled && !array_key_exists($pluginname, $plugins)) {
+            $plugins[$pluginname] = $pluginname;
+            $haschanged = true;
+        } else if (!$enabled && array_key_exists($pluginname, $plugins)) {
+            unset($plugins[$pluginname]);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('paygw_plugins_sortorder', !$enabled, $enabled, $pluginname);
+            self::set_enabled_plugins(array_flip($plugins));
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Sets the current plugin as enabled or disabled
+     * When enabling tries to guess the sortorder based on default rank returned by the plugin.
+     *
+     * @param bool $newstate
+     */
+    public function set_enabled(bool $newstate = true) {
+        self::enable_plugin($this->name, $newstate);
+    }
+
+    /**
+     * Set the list of enabled payment gateways in the specified sort order
+     * To be used when changing settings or in unit tests.
+     *
+     * @param string|array $list list of plugin names without frankenstyle prefix - comma-separated string or an array
+     */
+    public static function set_enabled_plugins($list) {
+        if (empty($list)) {
+            $list = [];
+        } else if (!is_array($list)) {
+            $list = explode(',', $list);
+        }
+        if ($list) {
+            $plugins = \core_plugin_manager::instance()->get_installed_plugins('paygw');
+            $list = array_intersect($list, array_keys($plugins));
+        }
+        set_config('paygw_plugins_sortorder', join(',', $list));
+        \core_plugin_manager::reset_caches();
+    }
+
+    /**
+     * Returns the list of currencies that the payment gateway supports.
+     *
+     * @return string[] An array of the currency codes in the three-character ISO-4217 format
+     */
+    public function get_supported_currencies(): array {
+        $classname = '\paygw_'.$this->name.'\gateway';
+
+        return $classname::get_supported_currencies();
+    }
+}

lib/classes/plugininfo/plagiarism.php

@@ -0,0 +1,68 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url, part_of_admin_tree, admin_externalpage;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for plagiarism plugins
+ */
+class plagiarism extends base {
+
+    public function get_settings_section_name() {
+        return 'plagiarism'. $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig or !file_exists($this->full_path('settings.php'))) {
+            return;
+        }
+
+        // No redirects here!!!
+        $section = $this->get_settings_section_name();
+        $settingsurl = new moodle_url($this->get_dir().'/settings.php');
+        $settings = new admin_externalpage($section, $this->displayname, $settingsurl,
+            'moodle/site:config', $this->is_enabled() === false);
+        $adminroot->add($parentnodename, $settings);
+    }
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        global $CFG;
+        return !empty($CFG->enableplagiarism) ? new moodle_url('/admin/plagiarism.php') : null;
+    }
+}

lib/classes/plugininfo/portfolio.php

@@ -0,0 +1,133 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url;
+
+/**
+ * Class for portfolios
+ */
+class portfolio extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $DB;
+
+        $enabled = array();
+        $rs = $DB->get_recordset('portfolio_instance', array('visible'=>1), 'plugin ASC', 'plugin');
+        foreach ($rs as $repository) {
+            $enabled[$repository->plugin] = $repository->plugin;
+        }
+        $rs->close();
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $DB, $CFG;
+
+        require_once($CFG->libdir . '/portfoliolib.php');
+
+        $haschanged = false;
+        $oldvalue = null;
+        $data = ['visible' => $enabled];
+        if ($plugin = $DB->get_record('portfolio_instance', ['plugin' => $pluginname])) {
+            $instance = portfolio_instance($plugin->id);
+            $oldvalue = $instance->get('visible');
+            if (empty($oldvalue) && $instance->instance_sanity_check()) {
+                throw new \moodle_exception('cannotsetvisible', 'portfolio');
+            }
+
+            // Only set visibility if it's different from the current value.
+            if ($oldvalue != $enabled) {
+                $haschanged = true;
+                $instance->set('visible', $enabled);
+                $instance->save();
+            }
+        } else {
+            $haschanged = true;
+            portfolio_static_function($pluginname, 'create_instance', $pluginname, $pluginname, $data);
+        }
+
+        if ($haschanged) {
+            // Include this information into config changes table.
+            add_to_config_log('portfolio_visibility', $oldvalue, $enabled, $pluginname);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/portfolio.php');
+    }
+
+    /**
+     * Defines if there should be a way to uninstall the plugin via the administration UI.
+     * @return boolean
+     */
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Pre-uninstall hook.
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     */
+    public function uninstall_cleanup() {
+        global $DB;
+
+        // Get all instances of this portfolio.
+        $count = $DB->count_records('portfolio_instance', array('plugin' => $this->name));
+        if ($count > 0) {
+            // This portfolio is in use, get the it's ID.
+            $rec = $DB->get_record('portfolio_instance', array('plugin' => $this->name));
+
+            // Remove all records from portfolio_instance_config.
+            $DB->delete_records('portfolio_instance_config', array('instance' => $rec->id));
+            // Remove all records from portfolio_instance_user.
+            $DB->delete_records('portfolio_instance_user', array('instance' => $rec->id));
+            // Remove all records from portfolio_log.
+            $DB->delete_records('portfolio_log', array('portfolio' => $rec->id));
+            // Remove all records from portfolio_tempdata.
+            $DB->delete_records('portfolio_tempdata', array('instance' => $rec->id));
+
+            // Remove the record from the portfolio_instance table.
+            $DB->delete_records('portfolio_instance', array('id' => $rec->id));
+        }
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/profilefield.php

@@ -0,0 +1,47 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class profilefield extends base {
+
+    public function is_uninstall_allowed() {
+        global $DB;
+        return !$DB->record_exists('user_info_field', array('datatype'=>$this->name));
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/user/profile/index.php');
+    }
+}

lib/classes/plugininfo/qbank.php

@@ -0,0 +1,168 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2021 Catalyst IT Australia Pty Ltd
+ * @author     Safat Shahin <safatshahin@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core\plugininfo;
+
+/**
+ * Base class for qbank plugins.
+ *
+ * @package    core
+ * @copyright  2021 Catalyst IT Australia Pty Ltd
+ * @author     Safat Shahin <safatshahin@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class qbank extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    public function is_uninstall_allowed(): bool {
+        if (in_array($this->name, \core_plugin_manager::standard_plugins_list('qbank'))) {
+            return false;
+        }
+        return true;
+    }
+
+    public static function get_manage_url(): \moodle_url {
+        return new \moodle_url('/admin/settings.php', ['section' => 'manageqbanks']);
+    }
+
+    public function get_settings_section_name() {
+        return $this->type . '_' . $this->name;
+    }
+
+    public static function get_plugins($type, $typerootdir, $typeclass, $pluginman): array {
+        global $CFG;
+
+        $qbank = parent::get_plugins($type, $typerootdir, $typeclass, $pluginman);
+        $order = array_keys($qbank);
+        $sortedqbanks = [];
+        foreach ($order as $qbankname) {
+            $sortedqbanks[$qbankname] = $qbank[$qbankname];
+        }
+        return $sortedqbanks;
+    }
+
+    public static function get_enabled_plugins(): ?array {
+        global $CFG;
+        $pluginmanager = \core_plugin_manager::instance();
+        $plugins = $pluginmanager->get_installed_plugins('qbank');
+
+        if (!$plugins) {
+            return [];
+        }
+
+        $plugins = array_keys($plugins);
+
+        // Filter to return only enabled plugins.
+        $enabled = [];
+        foreach ($plugins as $plugin) {
+            $qbankinfo = $pluginmanager->get_plugin_info('qbank_'.$plugin);
+            $qbankavailable = $qbankinfo->get_status();
+            if ($qbankavailable === \core_plugin_manager::PLUGIN_STATUS_MISSING) {
+                continue;
+            }
+            $disabled = get_config('qbank_' . $plugin, 'disabled');
+            if (empty($disabled)) {
+                $enabled[$plugin] = $plugin;
+            }
+        }
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $plugin = 'qbank_' . $pluginname;
+        $oldvalue = get_config($plugin, 'disabled');
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            set_config('disabled', $disabled, $plugin);
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config('disabled', $plugin);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log('disabled', $oldvalue, $disabled, $plugin);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    /**
+     * Checks if a qbank plugin is ready to be used.
+     * It checks the plugin status as well as the plugin is missing or not.
+     *
+     * @param string $fullpluginname the name of the plugin
+     * @return bool
+     */
+    public static function is_plugin_enabled($fullpluginname): bool {
+        $pluginmanager = \core_plugin_manager::instance();
+        $qbankinfo = $pluginmanager->get_plugin_info($fullpluginname);
+        if (empty($qbankinfo)) {
+            return false;
+        }
+        $qbankavailable = $qbankinfo->get_status();
+        if ($qbankavailable === \core_plugin_manager::PLUGIN_STATUS_MISSING ||
+                !empty(get_config($fullpluginname, 'disabled'))) {
+            return false;
+        }
+        return true;
+    }
+
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig): void {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        if (file_exists($this->full_path('settings.php'))) {
+            if ($this->name !== 'columnsortorder') {
+                $settings = new \admin_settingpage($section, $this->displayname,
+                                    'moodle/site:config', $this->is_enabled() === false);
+            }
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+}

lib/classes/plugininfo/qbehaviour.php

@@ -0,0 +1,143 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use core_plugin_manager;
+use moodle_url;
+
+/**
+ * Class for question behaviours.
+ */
+class qbehaviour extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        $plugins = core_plugin_manager::instance()->get_installed_plugins('qbehaviour');
+        if (!$plugins) {
+            return array();
+        }
+        if ($disabled = get_config('question', 'disabledbehaviours')) {
+            $disabled = explode(',', $disabled);
+        } else {
+            $disabled = array();
+        }
+
+        $enabled = array();
+        foreach ($plugins as $plugin => $version) {
+            if (in_array($plugin, $disabled)) {
+                continue;
+            }
+            $enabled[$plugin] = $plugin;
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+        $plugins = [];
+        $oldvalue = get_config('question', 'disabledbehaviours');
+        if (!empty($oldvalue)) {
+            $plugins = array_flip(explode(',', $oldvalue));
+        }
+        // Only set visibility if it's different from the current value.
+        if ($enabled && array_key_exists($pluginname, $plugins)) {
+            unset($plugins[$pluginname]);
+            $haschanged = true;
+        } else if (!$enabled && !array_key_exists($pluginname, $plugins)) {
+            $plugins[$pluginname] = $pluginname;
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            $new = implode(',', array_flip($plugins));
+            add_to_config_log('disabledbehaviours', $oldvalue, $new, 'question');
+            set_config('disabledbehaviours', $new, 'question');
+            // Reset caches.
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    public function is_uninstall_allowed() {
+        global $DB;
+
+        if ($this->name === 'missing') {
+            // qbehaviour_missing is used by the system. It cannot be uninstalled.
+            return false;
+        }
+
+        return !$DB->record_exists('question_attempts', array('behaviour' => $this->name));
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        if ($disabledbehaviours = get_config('question', 'disabledbehaviours')) {
+            $disabledbehaviours = explode(',', $disabledbehaviours);
+            $disabledbehaviours = array_unique($disabledbehaviours);
+        } else {
+            $disabledbehaviours = array();
+        }
+        if (($key = array_search($this->name, $disabledbehaviours)) !== false) {
+            unset($disabledbehaviours[$key]);
+            set_config('disabledbehaviours', implode(',', $disabledbehaviours), 'question');
+        }
+
+        if ($behaviourorder = get_config('question', 'behavioursortorder')) {
+            $behaviourorder = explode(',', $behaviourorder);
+            $behaviourorder = array_unique($behaviourorder);
+        } else {
+            $behaviourorder = array();
+        }
+        if (($key = array_search($this->name, $behaviourorder)) !== false) {
+            unset($behaviourorder[$key]);
+            set_config('behavioursortorder', implode(',', $behaviourorder), 'question');
+        }
+
+        parent::uninstall_cleanup();
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/qbehaviours.php');
+    }
+}

lib/classes/plugininfo/qformat.php

@@ -0,0 +1,35 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for question types
+ */
+class qformat extends base {
+    public function is_uninstall_allowed() {
+        return true;
+    }
+}

lib/classes/plugininfo/qtype.php

@@ -0,0 +1,161 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use core_plugin_manager;
+use moodle_url;
+use part_of_admin_tree;
+
+/**
+ * Class for question types
+ */
+class qtype extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $DB;
+
+        $plugins = core_plugin_manager::instance()->get_installed_plugins('qtype');
+        if (!$plugins) {
+            return array();
+        }
+        $installed = array();
+        foreach ($plugins as $plugin => $version) {
+            $installed[] = $plugin.'_disabled';
+        }
+
+        list($installed, $params) = $DB->get_in_or_equal($installed, SQL_PARAMS_NAMED);
+        $disabled = $DB->get_records_select('config_plugins', "name $installed AND plugin = 'question'", $params, 'plugin ASC');
+        foreach ($disabled as $conf) {
+            if (empty($conf->value)) {
+                continue;
+            }
+            $name = substr($conf->name, 0, -9);
+            unset($plugins[$name]);
+        }
+
+        $enabled = array();
+        foreach ($plugins as $plugin => $version) {
+            $enabled[$plugin] = $plugin;
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $settingname = $pluginname . '_disabled';
+        $oldvalue = get_config('question', $settingname);
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            set_config($settingname, $disabled, 'question');
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config($settingname, 'question');
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log($settingname, $oldvalue, $disabled, 'question');
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    public function is_uninstall_allowed() {
+        global $DB;
+
+        if ($this->name === 'missingtype') {
+            // qtype_missingtype is used by the system. It cannot be uninstalled.
+            return false;
+        }
+
+        return !$DB->record_exists('question', array('qtype' => $this->name));
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/qtypes.php');
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        // Delete any question configuration records mentioning this plugin.
+        unset_config($this->name . '_disabled', 'question');
+        unset_config($this->name . '_sortorder', 'question');
+
+        parent::uninstall_cleanup();
+    }
+
+    public function get_settings_section_name() {
+        return 'qtypesetting' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $qtype = $this;      // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = null;
+        $systemcontext = \context_system::instance();
+        if (($hassiteconfig || has_capability('moodle/question:config', $systemcontext)) &&
+            file_exists($this->full_path('settings.php'))) {
+            $settings = new admin_settingpage($section, $this->displayname,
+                'moodle/question:config', $this->is_enabled() === false);
+            include($this->full_path('settings.php')); // This may also set $settings to null.
+        }
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+}

lib/classes/plugininfo/report.php

@@ -0,0 +1,46 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class report extends base {
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/reports.php');
+    }
+}

lib/classes/plugininfo/repository.php

@@ -0,0 +1,190 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_externalpage;
+use moodle_url;
+use part_of_admin_tree;
+
+defined('MOODLE_INTERNAL') || die();
+require_once($CFG->dirroot . '/repository/lib.php');
+
+/**
+ * Class for repositories
+ */
+class repository extends base {
+
+    /** @var int Repository state, when it's enabled and visible. */
+    public const REPOSITORY_ON = 1;
+
+    /** @var int Repository state, when it's enabled but hidden. */
+    public const REPOSITORY_OFF = 0;
+
+    /** @var int Repository state, when it's disabled. */
+    public const REPOSITORY_DISABLED = -1;
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array|null of enabled plugins $pluginname=>$pluginname, null means unknown
+     */
+    public static function get_enabled_plugins() {
+        global $DB;
+        return $DB->get_records_menu('repository', null, 'type ASC', 'type, type AS val');
+    }
+
+    /**
+     * Returns current status for a pluginname.
+     *
+     * Repositories needs to be calculated in a different way than the default method in the base class because they need to take
+     * into account the value of the visible column too.
+     *
+     * @param string $pluginname The plugin name to check.
+     * @return int The current status (enabled, disabled...) of $pluginname.
+     */
+    public static function get_enabled_plugin(string $pluginname): int {
+        global $DB;
+
+        $repository = $DB->get_record('repository', ['type' => $pluginname]);
+        if ($repository) {
+            switch ($repository->visible) {
+                case 1:
+                    $value = self::REPOSITORY_ON;
+                    break;
+                default:
+                    $value = self::REPOSITORY_OFF;
+            }
+        } else {
+            $value = self::REPOSITORY_DISABLED;
+        }
+        return $value;
+    }
+
+    /**
+     * Enable or disable a plugin.
+     * When possible, the change will be stored into the config_log table, to let admins check when/who has modified it.
+     *
+     * @param string $pluginname The plugin name to enable/disable.
+     * @param int $enabled Whether the pluginname should be enabled and visible (1), enabled but hidden (0) or disabled (-1).
+     *
+     * @return bool Whether $pluginname has been updated or not.
+     */
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $DB;
+
+        $haschanged = false;
+
+        // Enabled repositories exist in 'repository' table.
+        // Visible = REPOSITORY_ON ==> Enabled and visible.
+        // Visible = REPOSITORY_OFF ==> Enabled but hidden.
+        // Disabled repositories don't exist in 'repository' table.
+        if ($plugin = $DB->get_record('repository', ['type' => $pluginname])) {
+            // The plugin is enabled.
+            $oldvalue = $plugin->visible;
+            $repositorytype = \repository::get_type_by_typename($pluginname);
+            if ($enabled == self::REPOSITORY_DISABLED) {
+                $haschanged = $repositorytype->delete();
+                $enabled = '';
+            } else if ($oldvalue != $enabled) {
+                $haschanged = $repositorytype->update_visibility($enabled);
+            }
+        } else {
+            // Not all repositories have their own 'repository' record created. Disabled repositories don't have one.
+            // Make changes only when we want to enable repository.
+            $oldvalue = '';
+            if ($enabled == self::REPOSITORY_ON || $enabled == self::REPOSITORY_OFF) {
+                $type = new \repository_type($pluginname, [], $enabled);
+                if (!$haschanged = $type->create()) {
+                    throw new \moodle_exception('invalidplugin', 'repository', '', $pluginname);
+                }
+            }
+        }
+        if ($haschanged) {
+            // Include this information into config changes table.
+            add_to_config_log('repository_visibility', $oldvalue, $enabled, $pluginname);
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    public function get_settings_section_name() {
+        return 'repositorysettings'.$this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if ($hassiteconfig && $this->is_enabled()) {
+            // Completely no access to repository setting when it is not enabled.
+            $sectionname = $this->get_settings_section_name();
+            $settings = new admin_externalpage($sectionname, $this->displayname,
+                new moodle_url('/admin/repository.php', ['action' => 'edit', 'repos' => $this->name]), 'moodle/site:config', false);
+            $adminroot->add($parentnodename, $settings);
+        }
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/repository.php');
+    }
+
+    /**
+     * Defines if there should be a way to uninstall the plugin via the administration UI.
+     * @return boolean
+     */
+    public function is_uninstall_allowed() {
+        if ($this->name === 'upload' || $this->name === 'coursefiles' || $this->name === 'user' || $this->name === 'recent') {
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    /**
+     * Pre-uninstall hook.
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     * Converts all linked files to standard files when repository is removed
+     * and cleans up all records in the DB for that repository.
+     */
+    public function uninstall_cleanup() {
+        global $CFG;
+        require_once($CFG->dirroot.'/repository/lib.php');
+
+        $repo = \repository::get_type_by_typename($this->name);
+        if ($repo) {
+            $repo->delete(true);
+        }
+
+        parent::uninstall_cleanup();
+    }
+}

lib/classes/plugininfo/search.php

@@ -0,0 +1,54 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2015 Daniel Neis
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for search plugins
+ *
+ * @package    core
+ * @copyright  2015 Daniel Neis
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class search extends base {
+
+    /**
+     * Is uninstall allowed or not.
+     *
+     * @return bool
+     */
+    public function is_uninstall_allowed() {
+        return true;
+    }
+
+    /**
+     * Returns the node name used in admin settings menu for this plugin settings (if applicable).
+     *
+     * @return null|string node name or null if plugin does not create settings node (default)
+     */
+    public function get_settings_section_name() {
+        return 'searchsetting' . $this->name;
+    }
+}

lib/classes/plugininfo/theme.php

@@ -0,0 +1,96 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2013 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for themes
+ */
+class theme extends base {
+    public function is_uninstall_allowed() {
+        global $CFG;
+
+        if ($this->name === 'boost') {
+            // All of these are protected for now.
+            return false;
+        }
+
+        if (!empty($CFG->theme) and $CFG->theme === $this->name) {
+            // Cannot uninstall default theme.
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Pre-uninstall hook.
+     *
+     * This is intended for disabling of plugin, some DB table purging, etc.
+     *
+     * NOTE: to be called from uninstall_plugin() only.
+     * @private
+     */
+    public function uninstall_cleanup() {
+        global $DB;
+
+        $DB->set_field('course', 'theme', '', array('theme'=>$this->name));
+        $DB->set_field('course_categories', 'theme', '', array('theme'=>$this->name));
+        $DB->set_field('user', 'theme', '', array('theme'=>$this->name));
+        $DB->set_field('mnet_host', 'theme', '', array('theme'=>$this->name));
+
+        if (get_config('core', 'thememobile') === $this->name) {
+            unset_config('thememobile');
+        }
+        if (get_config('core', 'themetablet') === $this->name) {
+            unset_config('themetablet');
+        }
+        if (get_config('core', 'themelegacy') === $this->name) {
+            unset_config('themelegacy');
+        }
+
+        $themelist = get_config('core', 'themelist');
+        if (!empty($themelist)) {
+            $themes = explode(',', $themelist);
+            $key = array_search($this->name, $themes);
+            if ($key !== false) {
+                unset($themes[$key]);
+                set_config('themelist', implode(',', $themes));
+            }
+        }
+
+        parent::uninstall_cleanup();
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/themeselector.php');
+    }
+}

lib/classes/plugininfo/tool.php

@@ -0,0 +1,84 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use moodle_url;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class for admin tool plugins
+ */
+class tool extends base {
+
+    public function is_uninstall_allowed() {
+        // Some mobile settings are used by the core.
+        if ($this->name === 'mobile') {
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    /**
+     * Tools cannot be disabled.
+     *
+     * @return boolean
+     */
+    public function is_enabled() {
+        return true;
+    }
+
+    /**
+     * Return URL used for management of plugins of this type.
+     * @return moodle_url
+     */
+    public static function get_manage_url() {
+        return new moodle_url('/admin/settings.php', ['section' => 'toolsmanagement']);
+    }
+
+    /**
+     * Loads plugin settings to the settings tree
+     *
+     * This function usually includes settings.php file in plugins folder.
+     * Alternatively it can create a link to some settings page (instance of admin_externalpage)
+     *
+     * @param \part_of_admin_tree $adminroot
+     * @param string $parentnodename
+     * @param bool $hassiteconfig whether the current user has moodle/site:config capability
+     */
+    public function load_settings(\part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (file_exists($this->full_path('settings.php'))) {
+            include($this->full_path('settings.php'));
+        }
+    }
+}

lib/classes/plugininfo/webservice.php

@@ -0,0 +1,126 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Defines classes used for plugin info.
+ *
+ * @package    core
+ * @copyright  2011 David Mudrak <david@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core\plugininfo;
+
+use admin_settingpage;
+use part_of_admin_tree;
+
+/**
+ * Class for webservice protocols
+ */
+class webservice extends base {
+
+    public static function plugintype_supports_disabling(): bool {
+        return true;
+    }
+
+    /**
+     * Finds all enabled plugins, the result may include missing plugins.
+     * @return array of enabled plugins $pluginname => $pluginname
+     */
+    public static function get_enabled_plugins() {
+        global $CFG;
+
+        if (empty($CFG->enablewebservices) or empty($CFG->webserviceprotocols)) {
+            return array();
+        }
+
+        $enabled = array();
+        foreach (explode(',', $CFG->webserviceprotocols) as $protocol) {
+            $enabled[$protocol] = $protocol;
+        }
+
+        return $enabled;
+    }
+
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        global $CFG;
+
+        $haschanged = false;
+        $plugins = [];
+        if (!empty($CFG->webserviceprotocols)) {
+            $plugins = array_flip(explode(',', $CFG->webserviceprotocols));
+        }
+
+        // Remove plugins that are no longer available.
+        $availablews = \core_component::get_plugin_list('webservice');
+        foreach ($plugins as $key => $notused) {
+            if (empty($availablews[$key])) {
+                unset($plugins[$key]);
+            }
+        }
+
+        // Only set visibility if it's different from the current value.
+        if ($enabled && !array_key_exists($pluginname, $plugins)) {
+            $plugins[$pluginname] = $pluginname;
+            $haschanged = true;
+        } else if (!$enabled && array_key_exists($pluginname, $plugins)) {
+            unset($plugins[$pluginname]);
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            $new = implode(',', array_flip($plugins));
+            add_to_config_log('webserviceprotocols', $CFG->webserviceprotocols ?? '', $new, 'core');
+            set_config('webserviceprotocols', $new);
+            // Reset caches.
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
+    public function get_settings_section_name() {
+        return 'webservicesetting' . $this->name;
+    }
+
+    public function load_settings(part_of_admin_tree $adminroot, $parentnodename, $hassiteconfig) {
+        global $CFG, $USER, $DB, $OUTPUT, $PAGE; // In case settings.php wants to refer to them.
+        /** @var \admin_root $ADMIN */
+        $ADMIN = $adminroot; // May be used in settings.php.
+        $plugininfo = $this; // Also can be used inside settings.php.
+        $webservice = $this; // Also can be used inside settings.php.
+
+        if (!$this->is_installed_and_upgraded()) {
+            return;
+        }
+
+        if (!$hassiteconfig or !file_exists($this->full_path('settings.php'))) {
+            return;
+        }
+
+        $section = $this->get_settings_section_name();
+
+        $settings = new admin_settingpage($section, $this->displayname, 'moodle/site:config', $this->is_enabled() === false);
+        include($this->full_path('settings.php')); // This may also set $settings to null.
+
+        if ($settings) {
+            $ADMIN->add($parentnodename, $settings);
+        }
+    }
+
+    public function is_uninstall_allowed() {
+        return true;
+    }
+}