Add Online food ordering for static website.

We have a static website for our restaurant , we want to add menu page and ability for guests to pre-order and make payment before they walk to our restaurant. This requires providing flexible menu management console for the restaurant manager to add menu items, modify items, change price, quantity, activate, deactivate items etc For the user, the ability to order one or more items from the menu, either via regular website or mobile device (most of the users will do it via mobile) , on checkout , make payment and select a time for the meal to be ready in the same day. This will require integrating with a payment gateway in India, that accept all debit and credit cards ( I can help suggest payment gateways, or hear to your suggestions on this, we can decide later) Once the order is placed, we would like to get order details sent via email, SMS and if possible by whatsup to our restaurant mobile phone. . Thanks, Diwakar