{-# LANGUAGE PackageImports, ScopedTypeVariables, TupleSections #-}
{-# OPTIONS -fno-warn-name-shadowing #-}
module Debian.Repo.Package.ToSourcePackage
    ( toSourcePackage
    ) where

import Data.List as List (intercalate, map, partition)
import Data.Maybe (catMaybes)
import qualified Data.Text as T (Text, unpack)
import Debian.Control (formatParagraph)
import qualified Debian.Control.Text as B (fieldValue, Paragraph)
import Debian.Repo.Package.Internal.ParseSourceParagraph (parseSourceParagraph)
import Debian.Repo.Types.PackageIndex (makeSourcePackageID, PackageIndex, SourceFileSpec(SourceFileSpec), SourcePackage(..))
import Debian.Version (parseDebianVersion)

toSourcePackage :: PackageIndex -> B.Paragraph -> SourcePackage
toSourcePackage index package =
    case (B.fieldValue "Directory" package,
          B.fieldValue "Files" package,
          B.fieldValue "Package" package,
          maybe Nothing (Just . parseDebianVersion . T.unpack) (B.fieldValue "Version" package)) of
      (Just directory, Just files, Just name, Just version) ->
          case (parseSourcesFileList files, parseSourceParagraph package) of
            (Right files', Right para) ->
                SourcePackage
                { sourcePackageID = makeSourcePackageID (T.unpack name) version
                , sourceParagraph = package
                , sourceControl = para
                , sourceDirectory = T.unpack directory
                , sourcePackageFiles = files' }
            (Left messages, _) -> error $ "Invalid file list: " ++ show messages
            (_, Left messages) -> error $ "Error in source paragraph\n package=" ++ show package ++ "\n  index=" ++ show index ++ "\n  messages:\n   " ++ intercalate "\n   " messages
      x -> error $ "Missing info in source package control information in " ++ show index ++ " -> " ++ show x ++ " :\n" ++ T.unpack (formatParagraph package)
    where
      -- Parse the list of files in a paragraph of a Sources index.
      parseSourcesFileList :: T.Text -> Either [String] [SourceFileSpec]
      parseSourcesFileList text =
          merge . catMaybes . List.map parseSourcesFiles . lines . T.unpack $ text
      parseSourcesFiles line =
          case words line of
            [md5sum, size, name] -> Just (Right (SourceFileSpec md5sum (read size) name))
            [] -> Nothing
            _ -> Just (Left ("Invalid line in Files list: '" ++ show line ++ "'"))
      merge x = case partition (either (const True) (const False)) x of
                  (a, []) -> Left . catMaybes . List.map (either Just (const Nothing )) $ a
                  (_, a) -> Right . catMaybes . List.map (either (const Nothing) Just) $ a