Write some Software

I'm looking for an integration between a Windows-based CRM program and Google's contacts and calendar. The CRM program is written in Visual FoxPro, and stores it's data in VFP data files. This application has a central calendar, and potentially multiple databases. What I want is an app that will, subject to each user's profile, find all calendar entries within a time range (for example, 7 days in the past thru 30 days in the future), take those entries along with selected information from linked contact records in a database, and add that information to the user's Google contacts and calendar. Then, look at the Google calendar and/or contacts, and see if any of those records need to be merged into the CRM's calendar and/or contact records, indicating completed or updated calendar entries and/or contact information. The app will probably need a user table, storing individual user's google information and preferences, and perhaps a gui to maintain those fields. The bulk of the app will need to be designed so that it can run from the task scheduler, and update multiple users with one run.