module Main where

import Control.Monad (unless)
import Data.Maybe (fromMaybe)
import System.Environment (getArgs)
import System.Exit (exitSuccess)

import EnvStatus.Config (getAppConfig, getConfigValue)
import EnvStatus.Output.Parse
import EnvStatus.Output.Render (renderTokenString)

main :: IO ()
main = do
  -- Args
  args <- getArgs
  validateArgs args
  -- Config
  cp <- getAppConfig
  let tokens = parseOutputFormat $ fromMaybe "" $ getConfigValue cp "output_template"
  -- Output result
  result <- renderTokenString cp tokens
  putStrLn result

validateArgs :: [String] -> IO ()
validateArgs args =
  unless (areArgsValid args) $ do
    printHelp
    exitSuccess

areArgsValid :: [String] -> Bool
areArgsValid args
  | null args = True
  | length args > 1 = False
  | head args == "--help" = False
  | otherwise = True

printHelp :: IO ()
printHelp = putStrLn $
  unlines [ ""
          , "envstatus [OPTIONS]"
          , ""
          , "envstatus extracts numerous information from the current execution environment and outputs it"
          , ""
          , "OPTIONS:"
          , "  --help            Displays this help"
          ]