{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards   #-}

import           Data.Aeson                 as AE
import           Data.Aeson.Types           as AET
import           Data.ByteString.Lazy       as BL
import           Data.ByteString.Lazy.Char8 as BL8
import           Prelude                    as P

-- THIS "id":1
--                          "key":null CHECKED, NULL
-- THIS "round_id":1        round title join
--                          "pos":1 RANKING? NOT USING
--                          "group_id":null
-- THIS "team1_id":45
-- THIS "team2_id":30
-- THIS "play_at":"2011-11-11 12:00:00.000000"
--                          "postponed":"f"  CHECKED, NULL
--                          "play_at_v2":null  CHECKED, NULL
--                          "play_at_v3":null  CHECKED, NULL
--                          "ground_id":null CHECKED, NULL
--                          "city_id":null CHECKED, NULL
--                          "knockout":"f"
--                          "home":"t"
-- THIS "score1":1          regular time
-- THIS "score2":0          regular time
-- THIS "score1et":null     extended time
-- THIS "score2et":null     extended time
-- THIS "score1p":null      penalty time
-- THIS "score2p":null      penalty time
--
--                          "score1i":null CHECKED, NULL
--                          "score2i":null CHECKED, NULL
--                          "score1ii":null CHECKED, NULL
--                          "score2ii":null CHECKED, NULL
--                          "next_game_id":null  CHECKED, NULL
--                          "prev_game_id":null  CHECKED, NULL
--                          "winner":1
--                          "winner90":1
--                          "created_at":"2016-09-28 03:35:02.277055"
--                          "updated_at":"2016-09-28 03:35:02.277055"

data Game = Game {
    round_id :: Value,
    team1_id :: Value,
    team2_id :: Value,
    playAt   :: Value,
    score1   :: Value,
    score2   :: Value,
    score1et :: Value,
    score2et :: Value,
    score1p  :: Value,
    score2p  :: Value } deriving (Show)

instance ToJSON Game where
    toJSON Game{..} = object [
        "rId" .= round_id,
        "t1" .= team1_id,
        "t2" .= team2_id,
        "ts" .= playAt,
        "s1" .= score1,
        "s2" .= score2,
        "s1e" .= score1et,
        "s2e" .= score2et,
        "s1p" .= score1p,
        "s2p" .= score2p ]

instance FromJSON Game where
    parseJSON = withObject "game" $ \o -> do
        round_id <- o .: "round_id"
        team1_id <- o .: "team1_id"
        team2_id <- o .: "team2_id"
        playAt <- o .: "play_at"
        score1 <- o .: "score1"
        score2 <- o .: "score2"
        score1et <- o .: "score1et"
        score2et <- o .: "score2et"
        score1p <- o .: "score1p"
        score2p <- o .: "score2p"
        return Game{..}

reduce :: [Game] -> Value -> [Game]
reduce acc x = case (parseEither parseJSON x :: Either String Game) of
    (Left s)  -> error s
    (Right v) -> v : acc

parseGames :: Either String [Value] -> [Game]
parseGames (Left x)   = error x
parseGames (Right xs) = P.foldl reduce [] xs

main :: IO ()
main = do
    src <- BL.readFile "./data/games.json"
    let games = parseGames (AE.eitherDecode src :: Either String [Value])
    let encoded = encode games
    BL8.putStrLn encoded
    BL8.putStrLn "Writing games.json"
    BL.writeFile "games.json" encoded