DiscussionModel::getUnreadCount PHP Method

    public function getUnreadCount($Wheres = '')
    {
        if (is_array($Wheres) && count($Wheres) == 0) {
            $Wheres = '';
        }
        // Check permission and limit to categories as necessary
        if ($this->Watching) {
            $Perms = CategoryModel::categoryWatch();
        } else {
            $Perms = self::categoryPermissions();
        }
        if (!$Wheres || count($Wheres) == 1 && isset($Wheres['d.CategoryID'])) {
            // Grab the counts from the faster category cache.
            if (isset($Wheres['d.CategoryID'])) {
                $CategoryIDs = (array) $Wheres['d.CategoryID'];
                if ($Perms === false) {
                    $CategoryIDs = [];
                } elseif (is_array($Perms)) {
                    $CategoryIDs = array_intersect($CategoryIDs, $Perms);
                }
                if (count($CategoryIDs) == 0) {
                    return 0;
                } else {
                    $Perms = $CategoryIDs;
                }
            }
            $Categories = CategoryModel::categories();
            $Count = 0;
            foreach ($Categories as $Cat) {
                if (is_array($Perms) && !in_array($Cat['CategoryID'], $Perms)) {
                    continue;
                }
                $Count += (int) $Cat['CountDiscussions'];
            }
            return $Count;
        }
        if ($Perms !== true) {
            $this->SQL->whereIn('c.CategoryID', $Perms);
        }
        $this->EventArguments['Wheres'] =& $Wheres;
        $this->fireEvent('BeforeGetUnreadCount');
        // @see 'BeforeGet' for consistency in count vs. results
        $this->SQL->select('d.DiscussionID', 'count', 'CountDiscussions')->from('Discussion d')->join('Category c', 'd.CategoryID = c.CategoryID')->join('UserDiscussion w', 'd.DiscussionID = w.DiscussionID and w.UserID = ' . Gdn::session()->UserID, 'left')->where('d.CountComments >', 'COALESCE(w.CountComments, 0)', true, false)->where($Wheres);
        $Result = $this->SQL->get()->firstRow()->CountDiscussions;
        return $Result;
    }