Revert "refactor: plan media type"

This reverts commit 3cd3a3f8c6.

src/PostgREST/MediaType.hs

@@ -1,9 +1,7 @@
 {-# LANGUAGE DuplicateRecordFields #-}
-{-# LANGUAGE LambdaCase            #-}
 
 module PostgREST.MediaType
   ( MediaType(..)
-  , NormalMedia(..)
   , MTPlanOption (..)
   , MTPlanFormat (..)
   , MTPlanAttrs(..)
@@ -15,29 +13,14 @@ module PostgREST.MediaType
 
 import qualified Data.ByteString          as BS
 import qualified Data.ByteString.Internal as BS (c2w)
-import qualified Data.List                as L
 import           Data.Maybe               (fromJust)
 
 import Network.HTTP.Types.Header (Header, hContentType)
 
 import Protolude
---
--- $setup
--- Setup for doctests
--- >>> import Text.Pretty.Simple (pPrint)
--- >>> deriving instance Show NormalMedia
--- >>> deriving instance Show MTPlanFormat
--- >>> deriving instance Show MTPlanOption
--- >>> deriving instance Show MTPlanAttrs
--- >>> deriving instance Show MediaType
 
 -- | Enumeration of currently supported media types
 data MediaType
-  = MTNormal NormalMedia
-  | MTPlan   MTPlanAttrs
-  deriving Eq
-
-data NormalMedia
   = MTApplicationJSON
   | MTSingularJSON
   | MTGeoJSON
@@ -49,95 +32,83 @@ data NormalMedia
   | MTOctetStream
   | MTAny
   | MTOther ByteString
+  | MTPlan MTPlanAttrs
   deriving Eq
 
-
-data MTPlanAttrs = MTPlanAttrs (Maybe NormalMedia) MTPlanFormat [MTPlanOption]
+data MTPlanAttrs = MTPlanAttrs (Maybe MediaType) MTPlanFormat [MTPlanOption]
 instance Eq MTPlanAttrs where
   MTPlanAttrs {} == MTPlanAttrs {} = True -- we don't care about the attributes when comparing two MTPlan media types
 
 data MTPlanOption
   = PlanAnalyze | PlanVerbose | PlanSettings | PlanBuffers | PlanWAL
-  deriving Eq
 
 data MTPlanFormat
   = PlanJSON | PlanText
-  deriving Eq
 
 -- | Convert MediaType to a Content-Type HTTP Header
 toContentType :: MediaType -> Header
 toContentType ct = (hContentType, toMime ct <> charset)
   where
     charset = case ct of
-      MTNormal MTOctetStream -> mempty
-      MTNormal (MTOther _)   -> mempty
-      _                      -> "; charset=utf-8"
+      MTOctetStream -> mempty
+      MTOther _     -> mempty
+      _             -> "; charset=utf-8"
 
 -- | Convert from MediaType to a ByteString representing the mime type
 toMime :: MediaType -> ByteString
-toMime (MTNormal x) = toMimeNormal x
+toMime MTApplicationJSON = "application/json"
+toMime MTGeoJSON         = "application/geo+json"
+toMime MTTextCSV         = "text/csv"
+toMime MTTextPlain       = "text/plain"
+toMime MTTextXML         = "text/xml"
+toMime MTOpenAPI         = "application/openapi+json"
+toMime MTSingularJSON    = "application/vnd.pgrst.object+json"
+toMime MTUrlEncoded      = "application/x-www-form-urlencoded"
+toMime MTOctetStream     = "application/octet-stream"
+toMime MTAny             = "*/*"
+toMime (MTOther ct)      = ct
 toMime (MTPlan (MTPlanAttrs mt fmt opts)) =
   "application/vnd.pgrst.plan+" <> toMimePlanFormat fmt <>
-  (if isNothing mt then mempty else "; for=\"" <> toMimeNormal (fromJust mt) <> "\"") <>
+  (if isNothing mt then mempty else "; for=\"" <> toMime (fromJust mt) <> "\"") <>
   (if null opts then mempty else "; options=" <> BS.intercalate "|" (toMimePlanOption <$> opts))
 
-toMimeNormal :: NormalMedia -> ByteString
-toMimeNormal = \case
-  MTApplicationJSON -> "application/json"
-  MTGeoJSON         -> "application/geo+json"
-  MTTextCSV         -> "text/csv"
-  MTTextPlain       -> "text/plain"
-  MTTextXML         -> "text/xml"
-  MTOpenAPI         -> "application/openapi+json"
-  MTSingularJSON    -> "application/vnd.pgrst.object+json"
-  MTUrlEncoded      -> "application/x-www-form-urlencoded"
-  MTOctetStream     -> "application/octet-stream"
-  MTAny             -> "*/*"
-  (MTOther ct)      -> ct
-
 toMimePlanOption :: MTPlanOption -> ByteString
-toMimePlanOption = \case
-  PlanAnalyze  -> "analyze"
-  PlanVerbose  -> "verbose"
-  PlanSettings -> "settings"
-  PlanBuffers  -> "buffers"
-  PlanWAL      -> "wal"
+toMimePlanOption PlanAnalyze  = "analyze"
+toMimePlanOption PlanVerbose  = "verbose"
+toMimePlanOption PlanSettings = "settings"
+toMimePlanOption PlanBuffers  = "buffers"
+toMimePlanOption PlanWAL      = "wal"
 
 toMimePlanFormat :: MTPlanFormat -> ByteString
 toMimePlanFormat PlanJSON = "json"
 toMimePlanFormat PlanText = "text"
 
--- | Convert from ByteString to MediaType.
---
--- >>> decodeMediaType "application/json"
--- MTNormal MTApplicationJSON
---
--- >>> decodeMediaType "application/vnd.pgrst.plan;"
--- MTPlan (MTPlanAttrs Nothing PlanText [])
---
--- >>> decodeMediaType "application/vnd.pgrst.plan;for=\"application/json\""
--- MTPlan (MTPlanAttrs (Just MTApplicationJSON) PlanText [])
---
--- >>> decodeMediaType "application/vnd.pgrst.plan;for=\"text/csv\""
--- MTPlan (MTPlanAttrs (Just MTTextCSV) PlanText [])
---
--- A plan media type inside "for" shouldn't recurse
---
--- >>> decodeMediaType "application/vnd.pgrst.plan;for=\"application/vnd.pgrst.plan\""
--- MTPlan (MTPlanAttrs (Just (MTOther "application/vnd.pgrst.plan")) PlanText [])
+-- | Convert from ByteString to MediaType. Warning: discards MIME parameters
 decodeMediaType :: BS.ByteString -> MediaType
-decodeMediaType bs =
-  case BS.split (BS.c2w ';') bs of
+decodeMediaType mt =
+  case BS.split (BS.c2w ';') mt of
+    "application/json":_                   -> MTApplicationJSON
+    "application/geo+json":_               -> MTGeoJSON
+    "text/csv":_                           -> MTTextCSV
+    "text/plain":_                         -> MTTextPlain
+    "text/xml":_                           -> MTTextXML
+    "application/openapi+json":_           -> MTOpenAPI
+    "application/vnd.pgrst.object+json":_  -> MTSingularJSON
+    "application/vnd.pgrst.object":_       -> MTSingularJSON
+    "application/x-www-form-urlencoded":_  -> MTUrlEncoded
+    "application/octet-stream":_           -> MTOctetStream
     "application/vnd.pgrst.plan":rest      -> getPlan PlanText rest
     "application/vnd.pgrst.plan+text":rest -> getPlan PlanText rest
     "application/vnd.pgrst.plan+json":rest -> getPlan PlanJSON rest
-    mt                                     -> MTNormal $ decodeNormalMediaType mt
+    "*/*":_                                -> MTAny
+    other:_                                -> MTOther other
+    _                                      -> MTAny
   where
     getPlan fmt rest =
      let
        opts         = BS.split (BS.c2w '|') $ fromMaybe mempty (BS.stripPrefix "options=" =<< find (BS.isPrefixOf "options=") rest)
        inOpts str   = str `elem` opts
-       mtFor        = decodeNormalMediaType . L.singleton . dropAround (== BS.c2w '"') <$> (BS.stripPrefix "for=" =<< find (BS.isPrefixOf "for=") rest)
+       mtFor        = decodeMediaType . dropAround (== BS.c2w '"') <$> (BS.stripPrefix "for=" =<< find (BS.isPrefixOf "for=") rest)
        dropAround p = BS.dropWhile p . BS.dropWhileEnd p in
      MTPlan $ MTPlanAttrs mtFor fmt $
       [PlanAnalyze  | inOpts "analyze" ] ++
@@ -146,26 +117,8 @@ decodeMediaType bs =
       [PlanBuffers  | inOpts "buffers" ] ++
       [PlanWAL      | inOpts "wal"     ]
 
--- | Convert from ByteString to MediaType. Warning: discards MIME parameters
-decodeNormalMediaType :: [BS.ByteString] -> NormalMedia
-decodeNormalMediaType bs =
-  case bs of
-    "application/json":_                  -> MTApplicationJSON
-    "application/geo+json":_              -> MTGeoJSON
-    "text/csv":_                          -> MTTextCSV
-    "text/plain":_                        -> MTTextPlain
-    "text/xml":_                          -> MTTextXML
-    "application/openapi+json":_          -> MTOpenAPI
-    "application/vnd.pgrst.object+json":_ -> MTSingularJSON
-    "application/vnd.pgrst.object":_      -> MTSingularJSON
-    "application/x-www-form-urlencoded":_ -> MTUrlEncoded
-    "application/octet-stream":_          -> MTOctetStream
-    "*/*":_                               -> MTAny
-    other:_                               -> MTOther other
-    _                                     -> MTAny
-
-getMediaType :: MediaType -> NormalMedia
+getMediaType :: MediaType -> MediaType
 getMediaType mt = case mt of
   MTPlan (MTPlanAttrs (Just mType) _ _) -> mType
   MTPlan (MTPlanAttrs Nothing _ _)      -> MTApplicationJSON
-  MTNormal x                            -> x
+  other                                 -> other