So sorry to hear that . Two type of people I detest the most, thieves and liars !
I am assuming from your avatar that you have an E85 (soft top). And I also assume that you (wisely) leave the doors unlocked, if you didn't you would also be telling us of a roof sliced open.
My brother told me years ago that you never lock a convertible...you only need a knife for a key!
Do you have comprehensive insurance? If so, depending on your deductible, it should cover most of the repair. At least that is the way it works over here.