{-# LANGUAGE TypeFamilies #-}

module HaskellWorks.Data.Json.Standard.Cursor.Slow
  ( Cursor
  , fromBsIbBp
  , fromByteString
  , fromForeignRegion
  , fromString
  ) where

import Data.Word
import Foreign.ForeignPtr
import HaskellWorks.Data.Json.Standard.Cursor.Generic
import HaskellWorks.Data.Json.Standard.Cursor.IbBp
import HaskellWorks.Data.Json.Standard.Cursor.Specific

import qualified Data.ByteString                             as BS
import qualified Data.ByteString.Char8                       as BSC
import qualified Data.ByteString.Internal                    as BSI
import qualified Data.Vector.Storable                        as DVS
import qualified HaskellWorks.Data.BalancedParens            as BP
import qualified HaskellWorks.Data.FromForeignRegion         as F
import qualified HaskellWorks.Data.Json.Standard.Cursor.IbBp as J

data Slow

instance SpecificCursor Slow where
  type CursorOf Slow = Cursor

type Cursor = GenericCursor BS.ByteString (DVS.Vector Word64) (BP.SimpleBalancedParens (DVS.Vector Word64))

fromBsIbBp :: BS.ByteString -> IbBp -> Cursor
fromBsIbBp bs ibBp = GenericCursor
  { cursorText      = bs
  , interests       = ibPart
  , balancedParens  = BP.SimpleBalancedParens bpPart
  , cursorRank      = 1
  }
  where J.IbBp ibPart bpPart = ibBp

fromByteString :: BS.ByteString -> Cursor
fromByteString bs = fromBsIbBp bs (J.slowToIbBp bs)

fromForeignRegion :: F.ForeignRegion -> Cursor
fromForeignRegion (fptr, offset, size) = fromByteString (BSI.fromForeignPtr (castForeignPtr fptr) offset size)

fromString :: String -> Cursor
fromString = fromByteString . BSC.pack