pituicat/src/Affection/MessageBus/Message.hs

{-# LANGUAGE RankNTypes #-}
module Affection.MessageBus.Message where

import Data.Time.Clock (UTCTime(..))

class Message msg where
  msgTime :: msg -> UTCTime

data SystemMessage m
  = MsgUserMessage
    { msgPayload :: m
    , msgWhen :: UTCTime
    }  -- ^ Generic user defined message with custom payload
  | MsgEngineReady UTCTime

instance Message (SystemMessage m) where
  msgTime (MsgUserMessage _ t) = t
  msgTime (MsgEngineReady t)   = t