hass1.hs

module Main where
import Text.ParserCombinators.Parsec


data ListItem = List ListItem [ListItem]
              | Value    String
              | Property String String

unwordsList :: [ListItem] -> String
unwordsList = unwords . map showVal

instance Show ListItem where show = showVal

showVal :: ListItem -> String
showVal (List main content) =  show main ++ "(\n" ++ unwordsList content ++ "\n)"
showVal (Value string) = string




parseList :: Int -> Parser ListItem
parseList n = do first <- parseItem n
                 rest  <- many $ try $ try (parseList (n+1)) <|> parseItem (n+1)
                 return $ List first rest

parseItem :: Int -> Parser ListItem
parseItem n = do count n (char ' ')
                 string <- manyTill anyChar newline
                 return $ Value string

{-
parseProperty :: -> Parser ListItem
parsePropenty = do name <- manyTill ':'
                   value <- manyTill anyChar newline
                   return $ Property name value
-}

str :: String
str = unlines [
    "body",
    " top: 1",
    " left: 1",
    " a",
    "  top: 1"
    ]