{-# OPTIONS_GHC -Wall #-}
{-# Language ScopedTypeVariables #-}

module Casadi.IOSchemes
       ( mkSchemeSX
       , mkSchemeMX
       , mkSchemeCRSSparsity
       ) where

import qualified Data.Map as M
import qualified Data.Set as S
import qualified Data.Foldable as F
import qualified Data.Vector as V

import Casadi.Core.Classes.Sparsity -- ( Sparsity, sparsity' )
import Casadi.Core.Classes.SX -- ( SX, sx )
import Casadi.Core.Classes.MX -- ( MX, mx )
import Casadi.Core.Classes.IOScheme -- ( ioScheme', ioScheme_size, ioScheme_entry )
import Casadi.Core.Enums ( InputOutputScheme(..) )

mkScheme :: forall a . IO a -> InputOutputScheme -> [(String,a)] -> IO (V.Vector a)
mkScheme newEmpty schemeEnum userVals = do
  sch <- ioScheme__22 schemeEnum
  size <- ioScheme_size sch
  let ks = take size [(0::Int)..]
  entries <- mapM (ioScheme_entry sch) ks
  let entrySet :: S.Set String
      entrySet = S.fromList entries

      -- map of user input {String:a}, already checked for duplicates
      userMap :: M.Map String a
      userMap = M.fromListWithKey err userVals
      err k _ _ = error $ "mkScheme: " ++ show schemeEnum ++ ": you gave key \"" ++ k ++ "\" more than once"

      userSet :: S.Set String
      userSet = M.keysSet userMap

  case F.toList (S.difference userSet entrySet) of
    [] -> return ()
    xs ->  error $ "mkScheme: " ++ show schemeEnum ++ ": you gave keys " ++ show xs ++ " which aren't valid, valid entries:\n" ++ show entries

  let getElem str = case M.lookup str userMap of
        Nothing -> newEmpty -- new empty
        Just x -> return x

--  name <- ioScheme_name sch
--  print size
--  print name
--  ioScheme_entryNames sch >>= putStrLn
--  mapM (ioScheme_entry sch) ks >>= print
--  mapM (ioScheme_entryEnum sch) ks >>= print
--  mapM (ioScheme_entryLabel sch) ks >>= print

  fmap V.fromList $ mapM getElem entries

mkSchemeSX :: InputOutputScheme -> [(String,SX)] -> IO (V.Vector SX)
mkSchemeSX = mkScheme sx__14

mkSchemeMX :: InputOutputScheme -> [(String,MX)] -> IO (V.Vector MX)
mkSchemeMX = mkScheme mx__8

mkSchemeCRSSparsity :: InputOutputScheme -> [(String,Sparsity)] -> IO (V.Vector Sparsity)
mkSchemeCRSSparsity = mkScheme sparsity__1