Create/Update/Delete Material Master and InfoRecord

What would be the best way to accomplish this ? BAPIS or BDC or anything else ? Can anyone who has done this before share their thoughts ?

I need to build an interface program that will read a file and automatically create/update/delete material master and inforecord (based on the indicator field).

The input file format is flexible.

What wolud be the best and least painful way to go ?