Prestashop Stock Management Systeme

What i'm looking for is a stock management system for my Prestashop store. Firstly it will need to be able to upload products in bulk from a csv file, that includes images, titles, categories, EAN numbers and quantities. After that i want to be able to upload my supplier csv files, to automatically change the stock and price on my site. As i have several suppliers, some will have the same products and i will need the software to be able to choose the cheapest price is they have over 4 in stock. For example; Supplier 1 - £39.99 10 in stock, Supplier 2 - £49.99 5 in stock, Supplier 3 £34.99 3 in stock. Software would need to choose Supplier 1 and use that price. The system will also need to add shipping costs to all products but is shown as Free Shipping to the customer. All the products will have a unique EAN number, so that they can be identified easily.