{-# LANGUAGE LambdaCase #-}
module Main where

import Data.Functor
import Data.List.Split
import Data.Map (Map)
import qualified Data.Map as Map

parse :: String -> (Map Int [Int], [[Int]])
parse s = let [a,b] = splitOn "\n\n" s in
  ( foldr (\[x,y] m -> Map.insertWith (++) (read x) ([read y]) m) Map.empty . (splitOn "|" <$>) $ lines a
  , ((read <$>) . splitOn "," <$>) $ lines b)

fix1 :: Map Int [Int] -> [Int] -> [Int]
fix1 _     [ ]  = [ ]
fix1 _     [x]  = [x]
fix1 r (x:y:es) = undefined --TODO

solve1 :: Map Int [Int] -> [[Int]] -> Int
solve1 r l = sum $ l <&> (\a -> let t = length a in a !! (t `div` 2)) . fix1 r

solve2 = undefined

main :: IO ()
main = readFile "inputs/5.example" <&> parse >>= \i ->
       print (uncurry solve1 i)
       --print (solve2 i)