{-# LANGUAGE BangPatterns #-}
module HaskellWorks.Data.Json.Internal.Slurp
( JsonState(..)
, slurpText
, slurpNumber
) where
import Data.Text
import Data.Word
import Data.Word8
import HaskellWorks.Data.Json.Standard.Cursor.Internal.Word8
import Prelude hiding (drop)
import qualified Data.Aeson.Parser.Internal as AP
import qualified Data.Attoparsec.ByteString as PBS
import qualified Data.ByteString as BS
import qualified Data.Text as T
data JsonState
= Escaped
| InJson
| InString
| InNumber
| InIdent
slurpText :: BS.ByteString -> Either Text Text
slurpText bs = case PBS.parseOnly AP.jstring bs of
Right t -> Right t
Left e -> Left (T.pack e)
slurpNumber :: BS.ByteString -> BS.ByteString
slurpNumber bs = let (!cs, _) = BS.unfoldrN (BS.length bs) genNumber (InJson, bs) in cs
where genNumber :: (JsonState, BS.ByteString) -> Maybe (Word8, (JsonState, BS.ByteString))
genNumber (InJson, cs) = case BS.uncons cs of
Just (!d, !ds) | isLeadingDigit d -> Just (d , (InNumber , ds))
Just (!d, !ds) -> Just (d , (InJson , ds))
Nothing -> Nothing
genNumber (InNumber, cs) = case BS.uncons cs of
Just (!d, !ds) | isTrailingDigit d -> Just (d , (InNumber , ds))
Just (!d, !ds) | d == _quotedbl -> Just (_parenleft , (InString , ds))
_ -> Nothing
genNumber (_, _) = Nothing