{-# LANGUAGE OverloadedStrings #-}

module Input where

import Types
import Parse

import Data.Char
import Data.Attoparsec.Text (parseOnly)
import qualified Data.Text as T
import qualified Data.Text.IO as T
import Text.CSV

fromCSV :: CSV -> [(Contestant, Task, Points)]
fromCSV xs = [(c,t,r > 0) | (c,t,r) <- concatMap row xs']
  where
    row (name:ys) = zipWith (resp name) tasks ys
    resp name task res = (T.pack name, task, readRes res)

    hasNames = (t1 == "") || (t1 == "name")
        where t1 = (filter (not . isSpace) . head . head) xs
    xs' | hasNames = tail xs
        | otherwise = xs

    tasks :: [T.Text]
    tasks | hasNames = (map T.pack . tail . head) xs
          | otherwise = map (T.pack . reverse . take 2 . (++ repeat '0') . reverse . show) [1::Int ..]
    readRes x = read x :: Int


readResponses :: FilePath -> IO [(Contestant, Task, Points)]
readResponses name = do
    s <- T.readFile name
    case parseOnly responsesParser s of
        Right r -> return r
        Left _ -> case parseCSV name . T.unpack $ s of
            Right csv -> return $ fromCSV csv
            Left _ -> error $ "could not parse " ++ name