{-# LANGUAGE OverloadedStrings #-}
module Main where

import Control.Monad
import Control.Monad.Identity
import Data.Char
import Data.Version
import Lambdabot.Main
import System.Console.GetOpt
import System.Environment
import System.Exit
import System.IO

import Lambdabot.Config.Telegram
import Modules      (modulesInfo)
import qualified Paths_lambdabot_telegram_plugins as P

flags :: [OptDescr (IO (DSum Config Identity))]
flags = 
  [ Option "h?" ["help"]  (NoArg (usage []))                      "Print this help message"
  , Option "l"  []        (arg "<level>"   consoleLogLevel level) "Set the logging level"
  , Option "t"  ["trust"] (arg "<package>" trustedPackages strs)  "Trust the specified packages when evaluating code"
  , Option "V"  ["version"] (NoArg version)                       "Print the version of lambdabot"
  , Option "X"  []        (arg "<extension>" languageExts strs)   "Set a GHC language extension for @run"
  , Option "n"  ["name"]  (arg "<name>" telegramBotName name)     "Set telegram bot name"
  ]
  where 
    arg :: String -> Config t -> (String -> IO t) -> ArgDescr (IO (DSum Config Identity))
    arg descr key fn = ReqArg (fmap (key ==>) . fn) descr
        
    strs = return . (:[])

    name  = return
        
    level str = case reads (map toUpper str) of
      (lv, []):_ -> return lv
      _          -> usage
        [ "Unknown log level."
        , "Valid levels are: " ++ show [minBound .. maxBound :: Priority]
        ]
        
versionString :: String
versionString = ("lambdabot version " ++ showVersion P.version)

version :: IO a
version = do
  putStrLn versionString
  exitWith ExitSuccess

usage :: [String] -> IO a
usage errors = do
  cmd <- getProgName
    
  let isErr = not (null errors)
      out = if isErr then stderr else stdout
    
  mapM_ (hPutStrLn out) errors
  when isErr (hPutStrLn out "")
    
  hPutStrLn out versionString
  hPutStr   out (usageInfo (cmd ++ " [options]") flags)
    
  exitWith (if isErr then ExitFailure 1 else ExitSuccess)

-- do argument handling
main :: IO ()
main = do
  (config, nonOpts, errors) <- getOpt Permute flags <$> getArgs
  when (not (null errors && null nonOpts)) (usage errors)
  config' <- sequence config
  dir <- P.getDataDir
  exitWith <=< lambdabotMain modulesInfo $
    [ dataDir ==> dir
    , disabledCommands ==> ["quit"]
    , telegramLambdabotVersion ==> P.version
    , onStartupCmds ==> ["telegram"]
    , enableInsults ==> False
    ] ++ config'