Import CSV from location - Export XML to another location - repost

We need to intergrate a courier to our E Commerce system Our E commerce system generates CSV files with the package data ( address / name etc ) but a new courier only accepts XML files so we need a bit of sftware to pole a directory for a new CSV file - then convert to XML and put in a new directory. Also we then need the tracking details to go from the courier software back into our E commerce system so we need to do the same thing again in reverse ( sort of ). So it needs to pole a location and open any XML file (containing the tracking data) and then convert this to a CSV and deposit it into another location where the E Commerce system poles looking for new data.