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32 lines
1.1 KiB
32 lines
1.1 KiB
{-# LANGUAGE OverloadedStrings #-}
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{-# LANGUAGE RecordWildCards #-}
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module Worldcup.Continents (Continents, Continent(..), parseContinents, lookupContinent) where
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import Data.Aeson
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import Data.Aeson.Types as AET
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import Data.HashMap.Strict as HM
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import Data.Maybe as M
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import Prelude as P
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type Continents = HashMap Int Continent
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data Continent = Continent {
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continentId :: Int,
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continentName :: String } deriving (Show)
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parseContinents :: Either String [Value] -> Continents
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parseContinents (Left x) = error x
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parseContinents (Right xs) = P.foldl reduce HM.empty xs where
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reduce acc x = case (parseEither parseJSON x :: Either String Continent) of
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(Left s) -> error s
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(Right v) -> HM.insert (continentId v) v acc
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lookupContinent :: Int -> Continents -> Continent
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lookupContinent _id hm = M.fromMaybe (Continent 999 "DNE") (HM.lookup _id hm)
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instance FromJSON Continent where
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parseJSON = withObject "continent" $ \o -> do
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continentId <- o .: "id"
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continentName <- o .: "name"
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return Continent{..}
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