{-# LANGUAGE TemplateHaskell   #-}
{-# LANGUAGE DeriveGeneric     #-}
{-# LANGUAGE TypeOperators     #-}
{-# LANGUAGE DataKinds         #-}
{-# LANGUAGE OverloadedStrings #-}

-- | Example that tweets from a "Madlibs" file.
module Web.Toboggan
    ( act
    , program
    , TwitterBot (..)
    ) where

import Text.Madlibs
import qualified Data.Text as T
import Web.Tweet
import Control.Monad
import System.Directory
import Options.Generic
import Data.Maybe

-- | Data type for a twitter bot: configuration options and a CLI option
data TwitterBot = TwitterBot { config :: FilePath <?> "Path to the .mad template"
                             , cred   :: Maybe FilePath <?> "Path to credentials file (default ~/.cred)"
                             , cron   :: Bool     <?> "Display example crontab for a twitter bot"
                             , extras :: [String] <?> "Extra inputs from command line"
                             } deriving (Generic)

instance ParseRecord TwitterBot

-- | The command-line executable
act :: IO ()
act = do
    twitterBot <- getRecord "Twitter bot generator"
    program twitterBot

-- | Turn a `TwitterBot` into an IO action
program :: TwitterBot -> IO ()
program twitterBot = do
    homeDir <- getHomeDirectory
    let configR = unHelpful . config $ twitterBot
    let ins = map T.pack $ unHelpful . extras $ twitterBot
    generatedText <- runFile ins configR
    let credR = fromMaybe (homeDir ++ "/.cred") . unHelpful . cred $ twitterBot
    if (unHelpful . cron $ twitterBot) then do
        dir <- getCurrentDirectory
        putStrLn (cronStr ++ "~/.local/bin/toboggan --cred " ++ dir ++ "/" ++ credR ++ " --config " ++ dir ++ "/" ++ configR ++ "\n")
    else
        pure ()
    void $ basicTweet (T.unpack generatedText) credR

-- | helper string for printing the crontab
cronStr :: String
cronStr = "\n# m  h  dom mon dow   command\
\  0 13  *   *   *    "