Can we have an indicator for key fragments?

Can we please have something on your profile, like it does with the first win of the day bonus, that shows you how many keys you have left and a countdown timer to your next key refresh? I'm not positive but I think that you have a system where you get like 4 keys, and then u wait like a week or so, and then the system refreshes and you can get 4 keys again, and so on. This makes it so I know when I can try out new champs that I don't own and not risk not getting a key,