Well you have an online system. Then you really don't have a choice. So yeah stick with the online system.
Now are you saying you need to out put that format or do you need to interpret the string into usable number?
Personally either way I would suggest going to where your getting the number and changing the way your getting the time.
in PHP using
mixed microtime ([ bool $get_as_float = false ] )
would return the time in milliseconds as of . which would be more fine precision for games.(http://php.net/manual/en/function.microtime.php). I really wouldn't suggest working with a full calender time stamp, but instead a numerical one where time is measured off of unix epoch.
If you need to work with the string value. I would suggest using this as as a starting sample.
time = tokenate(date, 1, " ")
hour = int(tokenate(time, 0, ":"))
min = int(tokenate(time, 1, ":"))
sec = int(tokenate(time, 2, ":"))
*to note it might be stringtoint() or toInt() or something like that.
sec += min * 60
sec += hour * 60 * 60
... keep going for day, month and year. except I would get the difference of year as of launch year of the game.
I really suggest getting time in ms or seconds of the epoch. Doing so will reduce your work, the server programmers work, bugs and headaches.
<?php $t=time(); echo($t); ?>
That would be the easier.