{-# LANGUAGE DeriveDataTypeable #-}

module Data.TeLML.Type (Document, Fragment (..), Tag (..)) where

import Control.DeepSeq (NFData (..))
import Data.Data (Data)
import Data.String (IsString (..))
import qualified Data.Text as T
import Data.Typeable (Typeable)

-- | A 'Document' is zero or more 'Fragment's.
type Document = [Fragment]

-- | A 'Fragment' is either a snippet of text (as indicated by the
--   'Text' constructor) or a tag (as indicated by the 'Tag'
--   constructor). The former is a raw string, and the latter consists
--   of a name followed by zero or more 'Document's.
data Fragment
  = TextFrag T.Text
  | TagFrag Tag
  deriving (Eq, Show, Typeable, Data)

data Tag = Tag
  { tagName :: T.Text,
    tagPayload :: [Document]
  }
  deriving (Eq, Show, Typeable, Data)

instance IsString Fragment where
  fromString = TextFrag . fromString

instance NFData Fragment where
  rnf (TextFrag s) = rnf s
  rnf (TagFrag t) = rnf t

instance NFData Tag where
  rnf (Tag n l) = rnf n `seq` rnf l