Shopify script modification and app

1. The xml datasource will come in a ZIP file, so we need to be downloaded and decompressed , code in script must change if need. 2. We need the upload the products that have price 0, if they are missing price node (as most of the cases) they will be uploaded with price 0. 3. Need to change certain products fields based on conditions, ex. some sub-brands should be filled as brands(vendors) in shopify depending of conditions. 4. We are going to need an external app or maybe some sort of modifications in our store to show a "call for price" text, and a form in the products page, so the customer can send the products details to the default email, by doing this the price of these products must be hidden in the entire. We managed to this throught an app in the shopify store, but we dont want to do this product by product, we need to do it in a massive way, example by collections.