Air carrier flight attendant reported luggage tug hit and critically damaged wing.

Narrative

Luggage tug hit the left wing. Shook the airplane and he dropped luggage off and left. The CA got off and checked the plane and asked what happened. I guess the ground crew gave a bogus story. That the belt loader hit the plane too hard which was impossible because it was already at the plane;stopped. The CA got back on the plane after saying he didn't see any damage and said we was ok to close as we was already loaded up with pax and ready for door closure. As I closed the cockpit door the ramp supervisor came up and said he needed to speak to the CA I called the CA on the inter phone and told him the ramp supervisor wanted to speak with him. He cracked the door and said what's wrong. They spoke and the CA said we're good to close a second time. Finally the ramp supervisor said he found a static wick on the ground and other damage to the wing. There was a huge crack in the wing. We deplaned and next came and said yes this plane isn't going anywhere so we went to the next gate for a plane swap. Airport Management called to make sure I was ok. I didn't know who they were so I had them speak to the captain but I also wanted them to get his side of what happened as well. I was truly disturbed by this whole situation. I had terrible thoughts and visions in my head about what could have possibly happened if we took that plane in the air.