{ callPackage
, config
, lib
, cudaPackages
, cudaSupport ? config.cudaSupport or false
, lang ? "en"
, webdoc ? false
, version ? null
/*
If you wish to completely override the src, use:
my_mathematica = mathematica.override {
  source = pkgs.requireFile {
    name = "Mathematica_XX.X.X_BNDL_LINUX.sh";
    # Get this hash via a command similar to this:
    # nix-store --query --hash \
    # $(nix store add-path Mathematica_XX.X.X_BNDL_LINUX.sh --name 'Mathematica_XX.X.X_BNDL_LINUX.sh')
    sha256 = "0000000000000000000000000000000000000000000000000000";
    message = ''
      Your override for Mathematica includes a different src for the installer,
      and it is missing.
    '';
    hashMode = "recursive";
  };
}
*/
, source ? null
}:

let versions = callPackage ./versions.nix { };

    matching-versions =
      lib.sort (v1: v2: lib.versionAtLeast v1.version v2.version) (lib.filter
        (v: v.lang == lang
            && (version == null || isMatching v.version version)
            && matchesDoc v)
        versions);

    found-version =
      if matching-versions == []
      then throw ("No registered Mathematica version found to match"
                  + " version=${toString version} and language=${lang},"
                  + " ${if webdoc
                        then "using web documentation"
                        else "and with local documentation"}")
      else lib.head matching-versions;

    specific-drv = ./. + "/${lib.versions.major found-version.version}.nix";

    real-drv = if lib.pathExists specific-drv
               then specific-drv
               else ./generic.nix;

    isMatching = v1: v2:
      let as      = lib.splitVersion v1;
          bs      = lib.splitVersion v2;
          n       = lib.min (lib.length as) (lib.length bs);
          sublist = l: lib.sublist 0 n l;
      in lib.compareLists lib.compare (sublist as) (sublist bs) == 0;

    matchesDoc = v:
      builtins.match (if webdoc
                      then ".*[0-9]_LINUX.sh"
                      else ".*[0-9]_BNDL_LINUX.sh") v.src.name != null;

in

callPackage real-drv {
  inherit cudaSupport cudaPackages;
  inherit (found-version) version lang;
  src = if source == null then found-version.src else source;
  name = ("mathematica"
          + lib.optionalString cudaSupport "-cuda"
          + "-${found-version.version}"
          + lib.optionalString (lang != "en") "-${lang}");
  meta = with lib; {
    description = "Wolfram Mathematica computational software system";
    homepage = "http://www.wolfram.com/mathematica/";
    license = licenses.unfree;
    sourceProvenance = with sourceTypes; [ binaryNativeCode ];
    maintainers = with maintainers; [ herberteuler ];
    platforms = [ "x86_64-linux" ];
  };
}