module Hakyll.Alias
    ( aliasCtxt
    , personCtxt
    ) where

import Prolog
import Hakyll
import Data.Alias
import Data.Name
import Data.Person


functionField1 :: String -> (String -> Compiler String) -> Context a
functionField1 n f = functionField n $ \case
    [x] -> \_ -> f x
    _ -> \_ -> fail $ "Expecting exactly one argument to " <> n

aliasCtxt :: (Ord a, FromAlias a x) => String -> (String -> Compiler a) -> (x -> Compiler String) -> AliasMap a x -> Context c
aliasCtxt name toa fromx amap = functionField1 name $ toa >=> flip resolveAlias amap >=> fromx


personCtxt :: AliasMap Name_ Person_ -> Context a
personCtxt = aliasCtxt "person" (parseName . toSL) (pure . toSL . personHtml)