The other day at some festival a few japanese friends asked me something to the effect of
アイスを買ってくるけど、行く?
But I had already asked a friend, who had not yet returned, to get some for me. So I said
ジェームズがもう買って来てくれたので大丈夫。
What I intended to say in English was "No thanks, James already went to get me some." But it seems that the japanese version of that statement could have multiple meanings.
How do I differentiate between "He already bought it for me (and has completed this process)" and "He has already gone to buy it for me (and has not yet completed this action)"?
(もう買ってきてくれている could be a possibility, but for some reason doesn't sound correct to me. )