/** * Reduce stock level of the product * Acts as an alias for modify_stock() * * @param int Amount to reduce by * @return int */ public function reduce_stock($by = -1) { if ($this->stock == '-9999999') { $_parent = new fflcommerce_product($this->ID); return $_parent->modify_stock(-$by); } else { return $this->modify_stock(-$by); } }