Check if Powershell runs in interactive or unattended mode

Is there a way to determine within a powershell scripts if it is being executeded in interactive or unattended mode?

pseudo code:

if (interactiveMode) {
    DoInteractiveStuff()
}

if (unattendedMode) {
 DoUnattendedStuff()
}

Of cource i could pass some argument to the script but it would be better if the scripts itself was able to determine the mode.

@fabian:Um, what's the difference?

Generally speaking a script should provide parameters which allow it to run completely silently, with interaction only being sought when required parameters aren't provided (and can't sensibly default to something)

@AndyC:Just a nice to have feature ... one less thing for the user to configure when executing the script. Also the way or powershell framework i structured it is a bit complicated to parse that paramter a lot of places. It would be a lot easier if the script it self could determine the mode