From 90021290ee217976ecf9bb339acc58ecdea1dffe Mon Sep 17 00:00:00 2001
From: sam marshall <s.marshall@open.ac.uk>
Date: Tue, 22 Nov 2011 16:16:23 +0000
Subject: [PATCH] MDL-30408 Allow modules the choice to not appear on 'Add
 a...' lists

This is useful for modules which are created by the system and are not supposed to be created by users. There are various reasons for doing this in third-party modules.
---
 course/edit_form.php | 10 +++++++++-
 course/lib.php       |  2 ++
 lib/adminlib.php     | 15 +++++++++++++--
 lib/moodlelib.php    |  2 ++
 4 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/course/edit_form.php b/course/edit_form.php
index a5bad505cb845..d87c9d13275d4 100644
--- a/course/edit_form.php
+++ b/course/edit_form.php
@@ -270,7 +270,15 @@ function definition() {
                 }
 
                 $mods = array(0=>get_string('allownone'));
-                $mods += $DB->get_records_menu('modules', array('visible'=>1), 'name', 'id, name');
+                $allmods = $DB->get_records_menu('modules', array('visible' => 1),
+                        'name', 'id, name');
+                foreach ($allmods as $key => $value) {
+                    // Add module to list unless it cannot be added by users anyway
+                    if (plugin_supports('mod', $value, FEATURE_MOD_ARCHETYPE, MOD_ARCHETYPE_OTHER) !==
+                            MOD_ARCHETYPE_SYSTEM) {
+                        $mods[$key] = get_string('pluginname', $value);
+                    }
+                }
                 $mform->addElement('select', 'allowedmods', get_string('to'), $mods, array('multiple'=>'multiple', 'size'=>'10'));
                 $mform->disabledIf('allowedmods', 'restrictmodules', 'eq', 0);
                 // defaults are already in $course
diff --git a/course/lib.php b/course/lib.php
index d9cbc003d1602..ae6bd994d40c4 100644
--- a/course/lib.php
+++ b/course/lib.php
@@ -1853,6 +1853,8 @@ function print_section_add_menus($course, $section, $modnames, $vertical=false,
             $archetype = plugin_supports('mod', $modname, FEATURE_MOD_ARCHETYPE, MOD_ARCHETYPE_OTHER);
             if ($archetype == MOD_ARCHETYPE_RESOURCE) {
                 $resources[$urlbase.$modname] = $modnamestr;
+            } else if ($archetype === MOD_ARCHETYPE_SYSTEM) {
+                // System modules cannot be added by user, do not add to dropdown
             } else {
                 // all other archetypes are considered activity
                 $activities[$urlbase.$modname] = $modnamestr;
diff --git a/lib/adminlib.php b/lib/adminlib.php
index 4eaaecb4ad79d..a071fdf4eda12 100644
--- a/lib/adminlib.php
+++ b/lib/adminlib.php
@@ -7896,6 +7896,8 @@ protected function process_form_data(array $form) {
  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class admin_setting_configmultiselect_modules extends admin_setting_configmultiselect {
+    private $excludesystem;
+
     /**
      * Calls parent::__construct - note array $choices is not required
      *
@@ -7903,9 +7905,12 @@ class admin_setting_configmultiselect_modules extends admin_setting_configmultis
      * @param string $visiblename localised setting name
      * @param string $description setting description
      * @param array $defaultsetting a plain array of default module ids
+     * @param bool $excludesystem If true, excludes modules with 'system' archetype
      */
-    public function __construct($name, $visiblename, $description, $defaultsetting = array()) {
+    public function __construct($name, $visiblename, $description, $defaultsetting = array(),
+            $excludesystem = true) {
         parent::__construct($name, $visiblename, $description, $defaultsetting, null);
+        $this->excludesystem = $excludesystem;
     }
 
     /**
@@ -7922,8 +7927,14 @@ public function load_choices() {
         global $CFG, $DB;
         $records = $DB->get_records('modules', array('visible'=>1), 'name');
         foreach ($records as $record) {
+            // Exclude modules if the code doesn't exist
             if (file_exists("$CFG->dirroot/mod/$record->name/lib.php")) {
-                $this->choices[$record->id] = $record->name;
+                // Also exclude system modules (if specified)
+                if (!($this->excludesystem &&
+                        plugin_supports('mod', $record->name, FEATURE_MOD_ARCHETYPE) ===
+                        MOD_ARCHETYPE_SYSTEM)) {
+                    $this->choices[$record->id] = $record->name;
+                }
             }
         }
         return true;
diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index 29142057ae13d..2b62236e374b8 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -417,6 +417,8 @@
 define('MOD_ARCHETYPE_RESOURCE', 1);
 /** Assignment module archetype */
 define('MOD_ARCHETYPE_ASSIGNMENT', 2);
+/** System (not user-addable) module archetype */
+define('MOD_ARCHETYPE_SYSTEM', 3);
 
 /**
  * Security token used for allowing access