Relink AI files in AI document

Ok. They don't have the property, but if I loop into placedItems, those embedded ones are in the loop?

If not, they're not my problem.

I just need to relink AI files, so, I need to have the name of the placedItem to  check if it's an AI file or not. Am I clear?

So, I'm trying something like:

for (var i=0; i<app.activeDocument.placedItems.length; i++) {
    if (app.activeDocument.placedItems.file.name.match(/\.ai$/i)) {
        alert(app.activeDocument.placedItems.name);
        }
    }

and a lot of variations like:

app.activeDocument.placedItems.file.name.match(/\.ai$/i)
app.activeDocument.placedItems.file.match(/\.ai$/i)
app.activeDocument.placedItems.name.match(/\.ai$/i)

None of them works, just because the code stops with the mentioned error.

Thank you so much for your help!