Warding weapon clarification

[MyrddinCCI]

I just picked up UC and noticed the spell Warding Weapon.

in the description it says:
"It lunges at opponents, as if guided by a martially trained hand, parrying and turning back melee attacks aimed at you, but does not strike back at any opponent nor does it damage them. The weapon serves only as a defense. While it protects you, you can cast spells without provoking attacks of opportunity, without the need to cast them defensively."

Does this mean that it basically turns back ALL attacks? Or just AoOs?

Thanks for help!

[Meister]

I think the effect of this spell is just "you can cast spells whitout aoos; enjoy your rounds".

But I add a question: what does it happen to the weapon when the duration is over? Does it fall on the ground? Does the arcanist catch it as a free action a second before the end of the spell?