From 0b29541706ed1e242c12fc6938472c107145efc0 Mon Sep 17 00:00:00 2001
From: Sergei Porfenovich <sergei.porfenovich@gmail.com>
Date: Fri, 2 Aug 2019 22:23:20 +0300
Subject: [PATCH] Autogroup Bug

---
 classes/domain/autogroup_set.php | 33 +++++++++++++++++++++++++-------
 classes/domain/group.php         |  8 ++++++--
 version.php                      |  2 +-
 3 files changed, 33 insertions(+), 10 deletions(-)

diff --git a/classes/domain/autogroup_set.php b/classes/domain/autogroup_set.php
index 8f1cafe..e4e9143 100644
--- a/classes/domain/autogroup_set.php
+++ b/classes/domain/autogroup_set.php
@@ -295,18 +295,27 @@ public function verify_user_group_membership(\stdclass $user, \moodle_database $
 
         //an array of groupids which will be populated as we ensure membership
         $validgroups = array();
+        $new_group = false;
 
         foreach ($eligiblegroups as $eligiblegroup){
-            if($group = $this->get_or_create_group_by_idnumber($eligiblegroup, $db)) {
+            list($group, $group_created) = $this->get_or_create_group_by_idnumber($eligiblegroup, $db);
+            if($group) {
                 $validgroups[] = $group->id;
                 $group->ensure_user_is_member($user->id);
+                if ($group->courseid == $this->courseid){
+                    if (!$new_group or $group_created){
+                        $new_group = $group->id;
+                    }
+                }
             }
         }
 
         //now run through other groups and ensure user is not a member
         foreach($this->groups as $key => $group){
             if(!in_array($group->id,$validgroups)){
-                $group->ensure_user_is_not_member($user->id);
+                if($group->ensure_user_is_not_member($user->id) and $new_group){
+                    $this->check_forums($user->id, $group->id, $new_group, $db);
+                }
             }
         }
 
@@ -358,7 +367,7 @@ private function get_autogroups(\moodle_database $db)
     /**
      * @param string $groupname
      * @param \moodle_database $db
-     * @return bool|domain/group
+     * @return [bool|domain/group, bool]
      */
     private function get_or_create_group_by_idnumber($group, \moodle_database $db)
     {
@@ -372,7 +381,6 @@ private function get_or_create_group_by_idnumber($group, \moodle_database $db)
         }
 
         $idnumber = $this->generate_group_idnumber($groupidnumber);
-        $result = null;
 
         //firstly run through existing groups and check for matches
         foreach($this->groups as $group){
@@ -383,7 +391,7 @@ private function get_or_create_group_by_idnumber($group, \moodle_database $db)
                     $group->update();
                 }
 
-                return $group;
+                return [$group, false];
             }
         }
 
@@ -404,10 +412,10 @@ private function get_or_create_group_by_idnumber($group, \moodle_database $db)
             $newgroup->create();
             $this->groups[$newgroup->id] = $newgroup;
         } catch (exception\invalid_group_argument $e){
-            return false;
+            return [false, false];
         }
 
-        return $this->groups[$newgroup->id];
+        return [$this->groups[$newgroup->id], true];
     }
 
     /**
@@ -602,6 +610,17 @@ private function validate_object($autogroupset)
         && $autogroupset->courseid > 0;
     }
 
+    /**
+     * @param int $user_id
+     * @param int $old_group_id
+     * @param int $new_group_id
+     * @param \moodle_database $db
+     */
+    private function check_forums($user_id, $old_group_id, $new_group_id,  \moodle_database $db){
+        $conditions = ['course' => $this->courseid, 'userid' => $user_id, 'groupid' => $old_group_id];
+        $db->set_field('forum_discussions', 'groupid', $new_group_id, $conditions);
+    }
+
     /**
      * An array of DB level attributes for an autogroup set
      * used for handling stdclass object conversion.
diff --git a/classes/domain/group.php b/classes/domain/group.php
index c487398..5d00f42 100644
--- a/classes/domain/group.php
+++ b/classes/domain/group.php
@@ -73,28 +73,32 @@ public function __construct ($group, \moodle_database $db)
 
     /**
      * @param int $userid
+     * @return bool
      */
     public function ensure_user_is_member($userid){
         foreach($this->members as $member){
             if ($member == $userid) {
-                return;
+                return false;
             }
         }
 
         //user was not found as a member so will now make member a user
         \groups_add_member($this->as_object(), $userid, 'local_autogroup');
-        return;
+        return true;
     }
 
     /**
      * @param int $userid
+     * @return bool
      */
     public function ensure_user_is_not_member($userid){
         foreach($this->members as $member){
             if ($member == $userid) {
                 \groups_remove_member($this->as_object(), $userid);
+                return true;
             }
         }
+        return false;
     }
 
     /**
diff --git a/version.php b/version.php
index bedfefd..0d010a3 100644
--- a/version.php
+++ b/version.php
@@ -30,7 +30,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version = 2018070300;
+$plugin->version = 2019080200;
 $plugin->requires = 2013111800.00;       // Requires this Moodle version (2.7).
 $plugin->release = '2.4';                // Plugin release.
 $plugin->component = 'local_autogroup';  // Full name of the plugin (used for diagnostics).