module Hakyll.Web.Template.Internal
( Template (..)
, TemplateElement (..)
) where
import Control.Applicative (pure, (<$>), (<*>))
import Data.Binary (Binary, get, getWord8, put, putWord8)
import Data.Typeable (Typeable)
import Hakyll.Core.Writable
newtype Template = Template
{ unTemplate :: [TemplateElement]
} deriving (Show, Eq, Binary, Typeable)
instance Writable Template where
write _ _ = return ()
data TemplateElement
= Chunk String
| Key String
| Escaped
| If String Template (Maybe Template)
| For String Template (Maybe Template)
| Partial String
deriving (Show, Eq, Typeable)
instance Binary TemplateElement where
put (Chunk string) = putWord8 0 >> put string
put (Key key) = putWord8 1 >> put key
put (Escaped) = putWord8 2
put (If key t f) = putWord8 3 >> put key >> put t >> put f
put (For key b s) = putWord8 4 >> put key >> put b >> put s
put (Partial p) = putWord8 5 >> put p
get = getWord8 >>= \tag -> case tag of
0 -> Chunk <$> get
1 -> Key <$> get
2 -> pure Escaped
3 -> If <$> get <*> get <*> get
4 -> For <$> get <*> get <*> get
5 -> Partial <$> get
_ -> error $
"Hakyll.Web.Template.Internal: Error reading cached template"