let
  pkgs = import <nixpkgs> {};
  inherit (import ../common/lib.nix) writeHaskellScript get-niv-path home-manager unstable niv haskellList;
  haskellBody = commandline:
    ''
    getNivPath dir = readTrim . get_niv_path ([i|#{dir :: String}/nix/sources.nix|] :: String)

    getNivAssign dir name = fmap process . getNivPath dir $ name
        where process str = ["-I", [i|#{name :: String}=#{str :: LBS.ByteString}|]]

    main = do
      (configDir:hostname:args) <- getArgs
      paths <- concat <$> mapM (getNivAssign configDir) ["nixpkgs", "unstable", "home-manager"]
      ${commandline}
    '';
  bins = [ get-niv-path pkgs.nix ];

  test-system-config = writeHaskellScript {
    name = "test-system-config";
    inherit bins;
  } (haskellBody
    ''
      nix $ ["build", "-f", "<nixpkgs/nixos>", "system"] ++ paths ++ ["-I", [i|nixos-config=#{configDir}/hosts/#{hostname}/configuration.nix|], "-o", [i|result-system-#{hostname}|]] ++ args
    '');

  test-home-config = writeHaskellScript {
    name = "test-home-config";
    inherit bins;
  } (haskellBody
    ''
      nix $ ["build", "-f", "<home-manager/home-manager/home-manager.nix>"] ++ paths ++ ["--argstr", "confPath", [i|#{configDir}/hosts/#{hostname}/home.nix|], "--argstr", "confAttr", "", "--out-link", [i|result-home-manager-#{hostname}|], "activationPackage"] ++ args
    '');

  repoSrc = "git@hera.m-0.eu:nixos-config";
  configPath = "/etc/nixos";
  systems = ["apollo"  "hera"];
  homes = ["apollo"  "hera"  "hephaistos"];
  keys = ["default"  "apollo"  "hera"];
  test-and-bump-config = writeHaskellScript {
    name = "test-and-bump-config";
    bins = [ test-system-config test-home-config pkgs.git pkgs.coreutils niv pkgs.git-crypt ];
    imports = [ "Control.Exception (bracket)" "System.Directory (withCurrentDirectory)" "Control.Monad (when)"];
  } ''
      checkout :: IO FilePath
      checkout = do
        dir <- LBSC.unpack <$> (readTrim $ mktemp "-d")
        git "clone" "${repoSrc}" dir
        return dir

      main = do
        path <- readTrim pwd
        bracket checkout (rm "-rf") $ \dir -> do
          withCurrentDirectory dir $ do
            mapM_ (\x -> git_crypt "unlock" ([i|${configPath}/.git/git-crypt/keys/#{x}|] :: String)) ${haskellList keys}
            ignoreFailure $ niv "update"
          mapM_ (test_system_config dir) ${haskellList systems}
          mapM_ (test_home_config dir) ${haskellList homes}
          changed <- ((mempty /=) <$>) . readTrim $ git "-C" dir "status" "--porcelain"
          when changed $ do
            git "-C" dir "config" "user.email" "maralorn@maralorn.de"
            git "-C" dir "config" "user.name" "maralorn (nix-auto-updater)"
            git "-C" dir "commit" "-am" "Update dependencies with niv"
            git "-C" dir "push"
    '';
in
{
  inherit test-system-config test-home-config test-and-bump-config;
}