Code to Change Visio VDW file programatically

We need a piece of C# code that would be able to open a Visio VDW (Visio Web Drawing file) and change the data connection from a Sharepoint list to other. The problem that we have is that we have a Visio file that connects to a Sharepoint List and works OK. But I need to be able to change the URL for that List programatically to another list in another site.