module Dodge.Inventory.CheckSlots (
    checkInvSlotsYou,
    crNumFreeSlots,
    maxInvSlots,
) where

import NewInt
import Control.Monad
import Dodge.Item.InvSize
import Control.Lens
import Data.Monoid
import Dodge.Data.World
import qualified IntMapHelp as IM

{- | checks whether or not an item will fit in your inventory
 if so return Just the next slot to be used
-}
checkInvSlotsYou :: Item -> World -> Maybe (NewInt InvInt)
checkInvSlotsYou it w = do
    ycr <- w ^? cWorld . lWorld . creatures . ix 0
    guard $ crNumFreeSlots (w ^. cWorld . lWorld . items) ycr >= itInvHeight it
    Just . NInt . IM.newKey . _unNIntMap $ _crInv ycr

-- the intmap should be _items
crNumFreeSlots :: IM.IntMap Item -> Creature -> Int
crNumFreeSlots m cr = maxInvSlots - invSize (fmap f (_crInv cr))
  where
    f i = m ^?! ix i

maxInvSlots :: Int
maxInvSlots = 250

invSize :: NewIntMap InvInt Item -> Int
invSize = alaf Sum foldMap itInvHeight