{
  config,
  lib,
  pkgs,
  ...
}:
with lib; let
  cfg = config.programs.elvish;
in {
  options.programs.elvish = {
    enable = mkEnableOption "Elvish, a friendly interactive shell and an expressive programming";

    defaultFromBash = mkOption {
      type = types.bool;
      default = cfg.enable;
      description = ''
        Launch automatically when an interactive Bash shell is started
      '';
    };

    zoxide = mkOption {
      type = types.bool;
      default = false;
      description = ''
        Enable zoxide smart directory switcher
      '';
    };

    starship = mkOption {
      type = types.bool;
      default = false;
      description = ''
        Use the starship prompt
      '';
    };

    direnv = mkOption {
      type = types.bool;
      default = false;
      description = ''
        Enable direnv integration for elvish
      '';
    };

    package = mkOption {
      type = types.package;
      default = pkgs.elvish;
      defaultText = literalExpression "pkgs.elvish";
      description = ''
        The elvish package to install. May be used to change the version.
      '';
    };

    initExtra = mkOption {
      type = types.lines;
      default = "";
      description = ''
        Elvish code called during interactive elvish shell
        initialisation.
      '';
    };
  };

  config = mkIf cfg.enable {
    home.packages = [cfg.package];

    # programs.man.generateCaches = mkDefault true;

    xdg.configFile."elvish/rc.elv".text = cfg.initExtra;

    programs.bash.enable = mkIf cfg.defaultFromBash true;
    programs.bash.initExtra = mkIf cfg.defaultFromBash ''
      exec elvish
    '';

    programs.starship.enableBashIntegration = mkIf cfg.defaultFromBash false;

    programs.starship.enable = mkIf cfg.starship true;
    programs.zoxide.enable = mkIf cfg.zoxide true;
    programs.direnv.enable = mkIf cfg.direnv true;

    programs.elvish.initExtra = mkMerge [
      (mkIf cfg.starship ''
        if (and (not-eq $E:TERM "dumb") (or (not (has-env "INSIDE_EMACS")) (eq $E:INSIDE_EMACS "vterm"))) {
          eval (${config.home.profileDirectory}/bin/starship init elvish)
        }
      '')
      (mkIf cfg.zoxide ''
        eval (${config.programs.zoxide.package}/bin/zoxide init elvish | slurp)
      '')
      (mkIf cfg.direnv ''
        eval (${pkgs.direnv}/bin/direnv hook elvish | ${pkgs.gnused}/bin/sed 's/except/catch/' | slurp)
      '')
    ];
  };
}