Method getAllCategories

public static function getAllCategories($filter = 0, $type = array(0, 1))
{
    $db = Factory::getDBO();
    $user = PhocacartUser::getUser();
    $userLevels = implode(',', $user->getAuthorisedViewLevels());
    $userGroups = implode(',', PhocacartGroup::getGroupsById($user->id, 1, 1));
    $wheres = array();
    if ($filter == 1) {
        // POS FILTER
        $paramsC = PhocacartUtils::getComponentParameters();
        $pos_categories = $paramsC->get('pos_categories', array(-1));
        if (in_array(-1, $pos_categories)) {
            // All categories selected
            $whereCat = '';
        } else {
            if (in_array(0, $pos_categories)) {
                // No category selected
                return false;
            } else {
                // Only some selected
                $wheres[] = ' c.id IN (' . implode(',', $pos_categories) . ')';
            }
        }
    }
    $wheres[] = " c.access IN (" . $userLevels . ")";
    $wheres[] = " (gc.group_id IN (" . $userGroups . ") OR gc.group_id IS NULL)";
    $wheres[] = " c.published = 1";
    if (!empty($type) && is_array($type)) {
        $wheres[] = " c.type IN (" . implode(',', $type) . ")";
    }
    $columns = 'c.id, c.title, c.alias, c.parent_id';
    $groupsFull = $columns;
    $groupsFast = 'c.id';
    $groups = PhocacartUtilsSettings::isFullGroupBy() ? $groupsFull : $groupsFast;
    $query = 'SELECT c.id, c.title, c.alias' . ' FROM #__phocacart_categories AS c' . ' LEFT JOIN #__phocacart_item_groups AS gc ON c.id = gc.item_id AND gc.type = 2' . ' WHERE ' . implode(' AND ', $wheres) . ' GROUP BY ' . $groups;
    $db->setQuery($query);
    $categories = $db->loadObjectList();
    return $categories;
}