[ Calculating local time with UTC offset ]
This is probably basic, but I can't seem to think straight when it comes to offset.
Currently, I display time by converting datetime from db like this:
date('g:i A', strtotime($given_date));
However, now I get an additional value from db, which UTC shows offset time in minutes, Currently it is: $offsetTime = -300;
So, to get the current local time, in this case I need to subtract, something like this
date('g:i A', strtotime($given_date) - $offsetTime * 60);
But what if offset is a positive number?
You state that $offsetTime already is a negative value
$offsetTime = -300;
Therefore you must add it to the date
date('g:i A', strtotime($given_date) + ($offsetTime * 60); // use plus-char
+ (-300 * 60) = + -18000 = - 18000
If you have a positive offset of let's say 120 you will get:
+ (120 * 60) = + 7200