Help with nbt tags

I am trying to make a item that if the player right clicks on a block while holding it, if they use a keybind and can open a GUI or interface from anywhere, but i am having trouble detecting where the player is looking and saving the x y and z of the block, i think if i give a nbt tag to a block when its right clicked with the item i can solve the problem with saving the x y and z but not the player direction, any help?