{ config, options, lib, home-manager, ... }:
with lib;
with lib.custom;
{
    options = with types; {
        user = mkOpt attrs {};

        home = {
            file       = mkOpt' attrs {} "Files to place directly in $HOME";
            configFile = mkOpt' attrs {} "Files to place in $XDG_CONFIG_HOME";
            dataFile   = mkOpt' attrs {} "Files to place in $XDG_DATA_HOME";
            dconfSettings = mkOpt' attrs {} "Configuration of dconf settings";
        };

        dotfiles = {
            dir = mkOpt path (removePrefix "/mnt" (findFirst pathExists (toString ../.) [
                  "/mnt/etc/dotfiles"
                  "/etc/dotfiles"
            ]));
            binDir     = mkOpt path "${config.dotfiles.dir}/bin";
            configDir  = mkOpt path "${config.dotfiles.dir}/config";
            modulesDir = mkOpt path "${config.dotfiles.dir}/modules";
            themesDir  = mkOpt path "${config.dotfiles.modulesDir}/themes";
        };

        env = mkOption {
            type = attrsOf (oneOf [ str path (listOf (either str path)) ]);
            apply = mapAttrs (n: v: if isList v then concatMapStringsSep ":" (x: toString x) v else (toString v));
            default = {};
            description = "TODO";
        };
    };

    config = {
        user = 
	let 
	    user = builtins.getEnv "USER";
	    name = if elem user [ "" "root" ] then "nafaryus" else user;
	in {
            inherit name;
            description = "L-Nafaryus";
            extraGroups = [ "wheel" ];
            isNormalUser = true;
            home = "/home/${name}";
            group = "users";
            uid = 1000;
        };

        # Install user packages to /etc/profiles instead. Necessary for
        # nixos-rebuild build-vm to work.
        home-manager = {
            useUserPackages = true;
            users.${config.user.name} = {
                home = {
                    file = mkAliasDefinitions options.home.file;
                    # Necessary for home-manager to work with flakes, otherwise it will
                    # look for a nixpkgs channel.
                    stateVersion = config.system.stateVersion;
                };
                xdg = {
                    configFile = mkAliasDefinitions options.home.configFile;
                    dataFile   = mkAliasDefinitions options.home.dataFile;
                };
                dconf = {
                    settings = mkAliasDefinitions options.home.dconfSettings;
                };
            };
        };

        users.users.${config.user.name} = mkAliasDefinitions options.user;

        nix.settings = let users = [ "root" config.user.name ]; in {
            trusted-users = users;
            allowed-users = users;
        };

        # must already begin with pre-existing PATH. Also, can't use binDir here,
        # because it contains a nix store path.
        env.PATH = [ "$DOTFILES_BIN" "$XDG_BIN_HOME" "$PATH" ];

        environment.extraInit = concatStringsSep "\n" (mapAttrsToList (n: v: "export ${n}=\"${v}\"") config.env);
    };
}