{
    config,
    lib,
    osConfig,
    ...
}: let
    cfg = config.myConfig.shell;
in {
    options.myConfig.shell = {
        bash.enable = lib.mkEnableOption "";
        zsh.enable = lib.mkEnableOption "";
        starship.enable = lib.mkEnableOption "";
        nixAliases = {
            enable = lib.mkEnableOption "";
            nix-helper.enable = lib.mkEnableOption "";
        };
        improvedCommands.enable = lib.mkEnableOption "";
        direnv.enable = lib.mkEnableOption "";
    };

    config = {
        assertions = [
            {
                assertion =
                    if cfg.nixAliases.nix-helper.enable
                    then osConfig.myConfig.nix-helper.enable
                    else true;
                message = "The nix-helper has to be enabled on the OS level.";
            }
        ];

        programs.bash.enable = cfg.bash.enable;

        programs.zsh.enable = cfg.zsh.enable;

        programs.starship = lib.mkIf cfg.starship.enable {
            enable = true;
            enableBashIntegration = cfg.bash.enable;
            enableZshIntegration = cfg.zsh.enable;
            settings = {
                cmd_duration.disabled = true;
                directory = {
                    truncation_length = 0;
                    truncation_symbol = "…/";
                    truncate_to_repo = false;
                };
            };
        };

        home.shellAliases = let
            nixAliases = lib.mkIf cfg.nixAliases.enable {
                nr =
                    if cfg.nixAliases.nix-helper.enable
                    then "nh os"
                    else "sudo nixos-rebuild --flake $FLAKE";
                nrs = "nr switch";
                nrt = "nr test";
                nrb = "nr boot";
                nrrb = "nrb && reboot";
                nu = "sudo nix flake update";
            };
            commandAliases = lib.mkIf cfg.improvedCommands.enable {
                cat = "bat -p";
            };
        in
            lib.mkMerge [nixAliases commandAliases];

        programs.lsd = lib.mkIf cfg.improvedCommands.enable {
            enable = true;
            enableAliases = true;
        };

        programs.bat.enable = cfg.improvedCommands.enable;

        programs.fzf.enable = cfg.improvedCommands.enable;

        programs.zoxide = lib.mkIf cfg.improvedCommands.enable {
            enable = true;
            options = ["--cmd cd"];
        };

        programs.direnv = lib.mkIf cfg.direnv.enable {
            enable = true;
            nix-direnv.enable = true;
            config.global.hide_env_diff = true;
        };
    };
}