PHP/MySQL web service to EPOS system

General information for the website: We want to read orders from Woocommerce into our EPOS system
Kind of development: Customization of existing website
Description of requirements/features: A Wordpress specialist in WooCommerce and MySQL is needed to create a small module in our Wordpress theme.

We run an Electronic Point of Sales company that help our user to install an EPOS system in their restaurant. Current business model is changing that many of their customers now wishes to order their deliveries online (rather than by phone). We normally use Wordpress template to setup our client's restaurant/takeaway shop as a presence on the Net. Now we need to extend this to include a WebStore.

Setting up a webstore is pretty easy using WooCommerce and we use SagePay to handle for all the monetary transaction. The problem arises that once the payment is clear, the website needs to inform the restaurant that an order is waiting. Currently, we sent up so that an email is sent to the restaurant. But now we want it to be automated.

By automation, we meant that the order will stay in WooCommerce, our software will periodically go online and check if there is any order waiting to be cook. We envisage that our EPOS software will need to FTP to the hosting company and connect to the MySQL database, then we need to read off the data and process within our program.

This is where we need the advise and help in creating the module. We want the WooCommerce part to be intact, ie, we do not modify any of the data tables etc. A module will be added so that once an order is complete, we want this module to pickup data from WooCommerce and place into a separate data table. It will hold in this table (and perhaps more to add) until the EPOS software reads it and empty it. Some sort of handshake will be needed so that both program can share the data without crashing. This module will also needs to read from the table when the order is finished, ie, cook and delivered, so as to complete the transaction.

As our customers have Chinese, Japanese, Pizza and Kebab shops/ restaurant, the online ordering system need to cater for all of their needs. In particular, pizza can have many options as toppings etc where plain vanilla WooCommerce "complex" product will not handle them. Therefore we are looking at a plugin call WPPIZZA. Is it the best one to go for? Do you have any experience in using it? This is where your speciality comes in. Can you advise for a more suitable template / plugin?

To summarise:
1. We want orders once placed and money accepted, to be copied to a new data table for our EPOS system to read.
2. Periodically read from the new data table to see if an order is mark complete. If so mark it in WooCommerce.
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