module EpubParser where

import Codec.Archive.Zip (toArchive, findEntryByPath, fromEntry, Archive)
import qualified Data.ByteString.Lazy as BL
import qualified Data.ByteString.Lazy.Char8 as C8

openEpub :: FilePath -> IO (Either String Archive)
openEpub path = toArchive <$> BL.readFile path >>= \archive -> maybe (pure $ Left "Error reading file") (\entry -> if fromEntry entry == C8.pack "application/epub+zip" then pure (Right archive) else pure (Left "Wrong mimetype")) (findEntryByPath "mimetype" archive)

getOpfPath :: Archive -> Maybe FilePath
getOpfPath archive = do
  entry <- findEntryByPath "META-INF/container.xml" archive

  return "OEBPS/content.opf"