{-# LANGUAGE
    UnicodeSyntax
  , ViewPatterns
  #-}
-- |A module to provide 'QuasiQuoter' for 'MIMEType' literals.
module Network.HTTP.Lucu.MIMEType.TH
    ( mimeType
    )
    where
import Control.Monad.Unicode
import Data.Ascii (Ascii)
import qualified Data.Ascii as A
import Language.Haskell.TH.Syntax
import Language.Haskell.TH.Quote
import Network.HTTP.Lucu.MIMEType hiding (mimeType)
import Network.HTTP.Lucu.Utils
import Prelude.Unicode

-- |'QuasiQuoter' for 'MIMEType' literals.
--
-- @
--   textPlain :: 'MIMEType'
--   textPlain = ['mimeType'| text/plain; charset=\"UTF-8\" |]
-- @
mimeType ∷ QuasiQuoter
mimeType = QuasiQuoter {
             quoteExp  = (lift ∘ parseMIMEType =≪) ∘ toAscii
           , quotePat  = const unsupported
           , quoteType = const unsupported
           , quoteDec  = const unsupported
           }
    where
      toAscii ∷ Monad m ⇒ String → m Ascii
      toAscii (A.fromChars ∘ trim → Just a) = return a
      toAscii str = fail $ "Malformed MIME Type: " ⧺ str

      unsupported ∷ Monad m ⇒ m α
      unsupported = fail "Unsupported usage of mimeType quasi-quoter."