以编程方式创建优惠券

Question

如何以编程方式在magento中为购物车价格规则创建规则和操作，条件小计等于或大于500.

Here Image that condition i want to write programmatically 那样：

conditions => array(
                        array(
                            'type' => 'salesrule/rule_condition_combine',
                            'aggregator' => 'all',
                            'value' => 1,
                            'new_child' => null
                        )
                    )