Get TranslationUnit right before AddOrUpdateTranslationUnits()

Hi!

The problem is that I'm working on an Adaptive MT plugin that supports updates, so I have my implementation of the method:

AddOrUpdateTranslationUnits(AddOrUpdateTranslationUnits(TranslationUnit[] translationUnits, int[] previousTranslationHashes, ImportSettings settings)

Here's the problem: my server in order to update a Translation unit requires the (1) source segment, the (2) existing taget segment and of course the (3) updated target segment. So as far as I understand here I don't have a direct way to access the segment right before the new edit.

My question here is: is there a way to achieve that?

A possible solution would be to store the target segment in some kind of persisten TranslationUnit metadata so that every time I receive this call, I will check if a previous translatition is available (if not, this is a simple Add and not an Update). But I cannot find anything that could do the trick.

Thanks for your help and support!