module StateIdentifiers where

import SplittingTree
import Trie qualified

import Data.Map.Strict qualified as Map

stateIdentifierFor :: (Ord i, Ord s) => s -> Partition s -> SplittingTree s i o -> Trie.Trie i
stateIdentifierFor state Partition{..} SplittingTree{..} = go firstNode
 where
  firstNode = fst <$> blockParent Map.!? (getPartition Map.! state)
  getParent n = fst <$> innerParent Map.!? n
  go Nothing = Trie.empty
  go (Just n) = Trie.insert (label Map.! n) (go (getParent n))