1  
 2  -- | Parse JSON input files
 3  
 4  module JSON where
 5  
 6  --------------------------------------------------------------------------------
 7  
 8  import Data.List
 9  import Data.Foldable           as F
10  import Data.Foldable.WithIndex as FI
11  
12  import Data.Map (Map)
13  import qualified Data.Map as Map 
14  
15  import qualified Data.Text       as T
16  import qualified Data.ByteString as B
17  
18  import Data.Aeson
19  import Data.Aeson.Key as Key
20  import Data.Scientific
21  
22  --------------------------------------------------------------------------------
23  
24  parseInputJsonValue :: Value -> Map String [Integer]
25  parseInputJsonValue val =
26    case val of 
27      Object obj -> Map.fromList (map worker (FI.itoList obj))
28      _ -> error "parseInputJsonValue: expecting a JSON object"
29    where
30  
31      worker (key,value) = (Key.toString key, flatten value)
32  
33      flatten :: Value -> [Integer]
34      flatten val = case val of
35        Number num -> numberToInteger num
36        Array  arr -> F.concatMap flatten arr  
37        String txt -> [read (T.unpack txt)]
38        _          -> error "parseInputJsonValue/flatten: expecting a number or an array"
39  
40      numberToInteger x = case floatingOrInteger x of
41        Right y -> [y]
42        Left  _ -> error "parseInputJsonValue/numberToInteger: expecting an integer"
43  
44  --------------------------------------------------------------------------------
45  
46  loadInputJsonFile :: FilePath -> IO (Map String [Integer])
47  loadInputJsonFile fpath = do
48    text <- B.readFile fpath
49    let Just value = decodeStrict text
50    return $ parseInputJsonValue value
51  
52  --------------------------------------------------------------------------------