aoc-2022/src/Parse.hs

{-# LANGUAGE ImportQualifiedPost #-}

module Parse where

import Common
import Data.Char (digitToInt)
import Data.Function ((&))
import Data.Text qualified as T
import Data.Void
import Text.Megaparsec qualified as M
import Text.Megaparsec.Char (digitChar)
import Text.Megaparsec.Char qualified as MC
import Text.Megaparsec.Char.Lexer qualified as MCL
import Util (both)

type Parser = M.Parsec Void T.Text

someLines :: Parser a -> Parser [a]
someLines p = p `M.sepEndBy1` MC.newline

number :: Parser Int
number = MCL.decimal

digit :: Parser Int
digit = digitToInt <$> digitChar

parsecDay ::
    Parser a ->
    (a -> Result, a -> Result) ->
    Day
parsecDay parser parts =
    ParsecDay
        ( \path text ->
            ( case M.parse (parser <* M.eof) path text of
                Left e -> Left $ M.errorBundlePretty e
                Right parsedInput -> Right $ both (parsedInput &) parts
            )
        )