AutoAssist addon

Hey guys,

When I played WoTLK retail I recall having an addon which automatically targeted the target of my target with spells and abilities (when they cannot be cast on target). For example, I can target my tank and cast Smite, it gets cast on my tanks target. Vice versa, I can target an enemy and cast heal, it heals the target of the enemy.

I believe this kind of behaviour was called "Auto Assist"

I've been trying to find an addon which does this but not found anything. I know this can be done with macros, but I've very used to this behaviour and would have to make a macro of basically every ability, which is tiresome. Thank you very much if you can help.