-- | A port of Kris Jenkins' RemoteData Elm module
-- <https://github.com/krisajenkins/remotedata>.
--
module Com.Simatime.Network where

data RemoteData a b
    = NotAsked
    | Loading
    | Failure a
    | Success b
    deriving (Eq, Show)

-- TODO figure out Http.Error
-- type WebData a = RemoteData Http.Error a

instance Functor (RemoteData a) where
    fmap _ NotAsked = NotAsked
    fmap _ Loading = Loading
    fmap _ (Failure a) = Failure a
    fmap f (Success a) = Success (f a)

instance Applicative (RemoteData e) where
    pure = Success
    NotAsked <*> _ = NotAsked
    Loading <*> _ = Loading
    Failure a <*> _ = Failure a
    Success a <*> b = fmap a b

fromEither :: Either a b -> RemoteData a b
fromEither (Left a) = Failure a
fromEither (Right a) = Success a