Like in Diablo, ESO items are randomly generated upon the creation of that item (looking a corpse, opening a chest, etc.). Items have a base item ID and an instance ID. Every item with the same name will have the same base item ID. This does not change, even though enchants and stats will be different from item to item. The instance ID is the identifier of that specific instance of the item. It is only useful to the client itself and the game devs.
The ESO API is limited in how much data may be gathered (and how that data is gathered) about items, unfortunately. For example, there are two ways to look at an item's level, which may give two different numbers. (The level might be weighted, return 0 instead of a level requirement, or just 50 for every VR Rank.) This is why some data must be entered into the addon and/or confirmed by you.
A future version of the addon will have enchant detection, though. I could do it based on the suffix added to the item name, but that would need to be localized. Another way is to look at the enchant id in the item link, but that requires compiling a list of every enchant ID. (Something that has been
started, but not completed yet.)
/edit: also in an AMA on Reddit, a dev said that they will add API for the detection of weapon and armor types. This should (hopefully) eliminate the dropdown for staff type as well, and allow me to not have to use a hack to figure this stuff out.
