Zen Cart import XML feed - repost

I use different suppliers who have .CSV and XML feeds available to download from their websites. These feeds include category and products details and attributes, prices, quantity etc. I need a script that would parse the xml feeds and import the data into my zen cart MySql DB in such a way that it would update existing product prices, sales prices, quantities and check if a product does not exist or is maked as deleted in the feed then add or delete the product accordingly.