How do I run an Apple Script only when the computer is awake at the specified time and NOT upon waking after the specified time?

Question

I've been using Steve Lambert's SelfControl to block myself from certain time-sucking internet sites for a certain period of time every day. I've automated the program launch using an AppleScript that runs based on an iCal alarm, but the problem is that if my computer has been asleep or shut off, the script will run as soon as I wake it up or start it up, and that can be very inconvenient if I'm intending to use my computer not during the hours when I intended to restrict access to such websites.
So, is there any way to schedule an AppleScript to run *only* if the computer is running at the designated time and not upon waking/starting up after the alarm has passed if the computer was asleep/off?
I started investigating launchd, as I understand this is the successor to cron/crontab in OS X Lion, but it appears that launchd has the same behavior I dislike in the iCal alarm approach--the script will run upon waking even if the time when it was supposed to run has already passed...unless there is a way to change this behavior?

Answer 1

The obvious/easy solution would be to add some logic to the script to see what the time is.
If you expect the script to run at, say, 1pm, but the script checks the time and sees that it's 5pm then you can assume the machine was asleep at the time and thefore you can bail out gracefully.
if (hours of (get current date)) = 13 then
  -- it's sometime in the 1pm hour...
end if
You can fine-tune the check as much as you like