@hackage / discord-haskell

{-# LANGUAGE OverloadedStrings #-}  -- allows "string literals" to be Text

import           Control.Monad (when, void)

import           UnliftIO.Concurrent

import           Data.Text (isPrefixOf, toLower, Text)

import qualified Data.Text.IO as TIO



import           Discord

import           Discord.Types

import qualified Discord.Requests as R



-- | Replies "pong" to every message that starts with "ping"

pingpongExample :: IO ()

pingpongExample = do

    userFacingError <- runDiscord $ def

             { discordToken = "Bot ZZZZZZZZZZZZZZZZZZZ"

             , discordOnEvent = eventHandler

             , discordOnLog = \s -> TIO.putStrLn s >> TIO.putStrLn ""

             } -- if you see OnLog error, post in the discord / open an issue



    TIO.putStrLn userFacingError

    -- userFacingError is an unrecoverable error

    -- put normal 'cleanup' code in discordOnEnd (see examples)



eventHandler :: Event -> DiscordHandler ()

eventHandler event = case event of

    MessageCreate m -> when (isPing m && not (fromBot m)) $ do

        void $ restCall (R.CreateReaction (messageChannelId m, messageId m) "eyes")

        threadDelay (2 * 10^6)

        void $ restCall (R.CreateMessage (messageChannelId m) "Pong!")

    _ -> return ()



fromBot :: Message -> Bool

fromBot = userIsBot . messageAuthor



isPing :: Message -> Bool

isPing = ("ping" `isPrefixOf`) . toLower . messageContent