Add an option for dumping a single table

lib/Graphics/Fountainhead/Metrics.hs

@@ -3,27 +3,66 @@
    obtain one at https://mozilla.org/MPL/2.0/. -}
 
 {-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE RecordWildCards #-}
 
 module Graphics.Fountainhead.Metrics
-    ( FontMetrics(..)
-    , afmFontMetrics
+    ( FontBBox(..)
+    , FontDescriptor(..)
+    , Number
+    , FontDescriptorFlag(..)
     ) where
 
-import qualified Data.Text.Lazy.Builder as Text.Builder
-import Data.Version (Version(..), showVersion)
-import Graphics.Fountainhead.Type (newlineBuilder)
+import Data.Text (Text)
 
-newtype FontMetrics = FontMetrics
-    { version :: Version
+type Number = Double
+
+data FontDescriptorFlag
+    = FixedPitch
+    | Serif
+    | Symbolic
+    | Script
+    | Nonsymbolic
+    | Italic
+    | AllCap
+    | SmallCap
+    | ForceBold
+    deriving (Eq, Show)
+
+instance Enum FontDescriptorFlag
+  where
+    toEnum 1 = FixedPitch
+    toEnum 2 = Serif
+    toEnum 3 = Symbolic
+    toEnum 4 = Script
+    toEnum 6 = Nonsymbolic
+    toEnum 7 = Italic
+    toEnum 17 = AllCap
+    toEnum 18 = SmallCap
+    toEnum 19 = ForceBold
+    toEnum _ = error "Font description flag is not supported."
+    fromEnum FixedPitch = 1
+    fromEnum Serif = 2
+    fromEnum Symbolic = 3
+    fromEnum Script = 4
+    fromEnum Nonsymbolic = 6
+    fromEnum Italic = 7
+    fromEnum AllCap = 17
+    fromEnum SmallCap = 18
+    fromEnum ForceBold = 19
+
+data FontBBox = FontBBox Number Number Number Number
+    deriving (Eq, Show)
+
+data FontDescriptor = FontDescriptor
+    { fontName :: Text
+    , flags :: [FontDescriptorFlag]
+    , fullName :: Text
+    , familyName :: Text
+    , weight :: Text
+    , fontBBox :: FontBBox
+    , version :: Text
+    , notice :: Text
+    , encodingScheme :: Text
+    , isFixedPitch :: Bool
+    , ascender :: Number
+    , descender :: Number
     } deriving (Eq, Show)
-
-afmKeyString :: Text.Builder.Builder -> String -> Text.Builder.Builder
-afmKeyString key value = key <> Text.Builder.singleton '\t'
-    <> Text.Builder.fromString value <> newlineBuilder
-
-afmFontMetrics :: FontMetrics -> Text.Builder.Builder
-afmFontMetrics FontMetrics{..}
-    = afmKeyString "StartFontMetrics" (showVersion version)
-    <> afmKeyString "Comment" "Generated by Fountainhead"
-    <> "EndFontMetrics" <> newlineBuilder