module Ringo.ArgParser (ProgArgs(..), parseArgs) where

import qualified Data.Text as Text

import Data.List (intercalate)
import Options.Applicative

import Ringo.Types

data ProgArgs = ProgArgs
                { progSettings  :: Settings
                , progInputFile :: FilePath
                , progOutputDir :: FilePath
                } deriving (Eq, Show)

settingsParser :: Parser Settings
settingsParser = let Settings {..} = defSettings
  in Settings
     <$> (Text.pack <$> strOption (long "dim-prefix"
                                   <> short 'd'
                                   <> value (Text.unpack settingDimPrefix)
                                   <> showDefault
                                   <> help "Prefix for dimension tables"))
     <*> (Text.pack <$> strOption (long "fact-prefix"
                                   <> short 'f'
                                   <> value (Text.unpack settingFactPrefix)
                                   <> showDefault
                                   <> help "Prefix for fact tables"))
     <*> option auto (let timeunits = map show [Second ..]
                      in long "timeunit"
                         <> short 't'
                         <> value settingTimeUnit
                         <> showDefault
                         <> completeWith timeunits
                         <> help ("Time unit granularity for fact tables. Possible values: "
                                    ++ intercalate ", " timeunits))

progArgsParser :: Parser ProgArgs
progArgsParser =
  ProgArgs
  <$> settingsParser
  <*> argument str (metavar "INPUT"
                    <> action "file"
                    <> help "Input file")
  <*> argument str (metavar "OUTPUT"
                    <> action "directory"
                    <> help "Output directory")

parseArgs :: IO ProgArgs
parseArgs = execParser opts
  where
    opts = info (helper <*> progArgsParser)
                (fullDesc
                 <> progDesc "Transforms OLTP database schemas to OLAP database star schemas"
                 <> header "ringo - OLTP to OLAP schema transformer"
                 <> footer "Source: http://github.com/quintype/ringo")