module Dhall.LSP.Backend.Formatting (formatExpr, formatExprWithHeader) where

import Data.Text    (Text)
import Dhall.Core   (Expr)
import Dhall.Parser (Header (..))
import Dhall.Pretty (CharacterSet (..))
import Dhall.Src    (Src)

import qualified Data.Text.Prettyprint.Doc             as Pretty
import qualified Data.Text.Prettyprint.Doc.Render.Text as Pretty
import qualified Dhall.Pretty

-- | Pretty-print the given Dhall expression.
formatExpr :: Pretty.Pretty b => CharacterSet -> Expr Src b -> Text
formatExpr charSet expr =
      Pretty.renderStrict
    . Dhall.Pretty.layout
    $ Dhall.Pretty.prettyCharacterSet charSet expr

-- | Pretty-print the given Dhall expression, prepending the given a "header"
--   (usually consisting of comments and whitespace).
formatExprWithHeader :: Pretty.Pretty b => CharacterSet -> Expr Src b -> Header -> Text
formatExprWithHeader charSet expr (Header header) = Pretty.renderStrict
  (Dhall.Pretty.layout doc)
  where
    doc =
      Pretty.pretty header
        <> Dhall.Pretty.prettyCharacterSet charSet expr
        <> "\n"