{-# LANGUAGE FlexibleContexts #-}
{-# OPTIONS_GHC -Wall         #-}

module HarmTrace.Base.Parsing ( parseData, parseDataWithErrors
                              , pString, pLineEnd
                              , module Data.ListLike.Base
                              , module Text.ParserCombinators.UU 
                              , module Text.ParserCombinators.UU.Utils
                              , module Text.ParserCombinators.UU.BasicInstances
                              ) where

import Text.ParserCombinators.UU
import Text.ParserCombinators.UU.Utils hiding (pSpaces)
import Text.ParserCombinators.UU.BasicInstances hiding (IsLocationUpdatedBy)
import Data.ListLike.Base (ListLike)

--------------------------------------------------------------------------------
-- A collection of parsing functions used by parsers throughout the project
--------------------------------------------------------------------------------     

-- toplevel parsers
parseData :: (ListLike s a, Show a) => P (Str a s LineColPos) b -> s -> b
parseData p inp = fst ( parseDataWithErrors p inp )

parseDataWithErrors :: (ListLike s a, Show a) 
                    =>  P (Str a s LineColPos) b -> s -> (b, [Error LineColPos])
parseDataWithErrors p inp = (parse ( (,) <$> p <*> pEnd) 
                             (createStr (LineColPos 0 0 0) inp))
                                                 
-- parses specific string
pString :: (ListLike state a, IsLocationUpdatedBy loc a, Show a, Eq a) 
        => [a] -> P (Str a state loc) [a]
pString s = foldr (\a b -> (:) <$> a <*> b) (pure []) (map pSym s)                             

-- parses whitespace (@pedro: should probably not contain '\n')
-- pSpaces :: Parser Char
-- pSpaces = pAnySym [' ','\n','\t']

-- parses UNIX and DOS/WINDOWS line endings
pLineEnd :: Parser String
pLineEnd  = pString "\n" <|> pString "\r\n" <|> pString " " <|> pString "\t"