An API to get the npc type?

[Tercio]

I'm looking for a better way to know which type the npc is.
For instance, I do click on a npc to select it, and, how do I know if this npc I've selected is a merchant, flight master or an tailor trainer?
At the moment I'm scanning the tooltip and searching for some keywords which can tell me what the npc does, but I'm wondering/searching if isn't an API or a better way to get this information.

Thank you.

[Platinengel]

I would try something like

if tooltip contains XXXXXX return true



http://wowprogramming.com/docs/widgets/GameTooltip

Here you could find something.

isUnit = GameTooltip:IsUnit("unit")

name, unit = GameTooltip:GetUnit()