Kiosk: fixing time=0 bug

[srietkerk]

For the time flag, I made sure that the user couldn't specify higher than 240, but didn't check the floor. The regex allows the time=0 to pass through, and right now, it makes the UI kinda freak out. It wasn't apparent to me whether or not it was making a lot of requests to the backend at the time, but either way, it's something to be fixed.

We don't want time=0 to be possible, so I've made it so that if time=0 is specified, it will just resort to the default.

One thing to note as this change will still allow time entries like 024 or any number that starts with 0 or 00. It will just take the value of the first non-zero numbers. For example, 024 just resulted in a 24 hour code. Something like 001 will just result in an hour long code.

I know we can limit this with the regex by making it so leading zeros aren't valid; this will just make the timeout the default 30 minutes.

I don't have a strong preference for one over the other, but the zero check is the first solution I thought of.

[eanders-ms]

You mention this is a user supplied value. Can it be negative? Can it parse to NaN?

[srietkerk]

You mention this is a user supplied value. Can it be negative? Can it parse to NaN?

@eanders-ms, no, it can't be negative because of the regex. If the user passes in something like -1 or (x+5) or anything that is not a number after the equal sign first, it will be viewed as an invalid entry. If a user input something like time=0-1, the regex would only take the 0.

[jwunderl]

behavior change lgtm but I'd lean towards avoiding nested ternaries when it's easy~