Discount engine in Javascript (Ionic framework/jQuery)

I want a promotion/discount rule engine in Javascript (Jquery/ionic framwork) format for use in a Ionic Framework mobile application (should be usable via a browser also). A suggestion would be to use node-rules open source as a framework. The final solution would be scalable, modular and tested by seeing it work in a simple IONIC framework application (offline). (GUI can be as simplistic or plain. Its strictly to test the feature works). High level Required promotion/discount rules are: - Discounts with quantity steps, of ‘Buy X Get Y’ type: Buy x Quantity of selected products or category of products (excluding some products or category of products) and get the cheapest Y quantity of products (category of products) free - Discount items to a fixed price discount (unconditional or based on minimum qua - Discount items to a percentage discount some rules: The following must be options in the rules • Must be assigned to a customer, or customer category (excluding xxx customers or yyy customer categories. • Customer had spent a certain amount in the cart • Customer had spent a certain amount on these products or categories of products • Customer has the product categories in the cart (excluding some products or product categories.) • Customer has all of these products or categories of products in the cart • Customer has one of these products or categories of products in the cart Feel free to setup a database as you deem to enable demonstration of the demo. I can also provide a sample database structure if that would make it easier. User requirement design document is also attached. Kindly bid with your final fixed fee offer. I will not go into side negotiations or upfront payments or other games played by some developers here. Payments will be via Freelancer Milestones for complete project. IN SUMMARY: It is making a Javascript library replica version of "WooCommerce All discounts" plugin [login to view URL] that can be used offline on a mobile ionic framework shopping cart or custom web app.