Tried it. Actually it's kinda cool. I was just about to start writing something like that

You saved me some time. I wouldn't mind buying it if it had more features.
The daily files are getting deleted from Apple web-site, so people download and keep them locally. Some option to pick those files would be useful. What I did, I ungziped and copied them to "/Documents and Files/Appliaction Data/blablabla/sales_data/" and it worked.
Of course lot's of features are missing, but even this light version I find useful.