{ config, pkgs, lib, ... }:
let
  cfg = config.services.greg-ng;
in
{
  options.services.greg-ng = {
    enable = lib.mkEnableOption "greg-ng, an mpv based media player";

    package = lib.mkPackageOption pkgs "greg-ng" { };

    mpvPackage = lib.mkPackageOption pkgs "mpv" { };

    # TODO: create some better descriptions
    settings = {
      host = lib.mkOption {
        type = lib.types.str;
        default = "localhost";
        example = "0.0.0.0";
        description = ''
          Which host to bind to.
        '';
      };

      port = lib.mkOption {
        type = lib.types.port;
        default = 8008;
        example = 10008;
        description = ''
          Which port to bind to.
        '';
      };

      mpv-socket-path = lib.mkOption {
        type = lib.types.str;
        default = "%t/greg-ng-mpv.sock";
        description = ''
          Path to the mpv socket.
        '';
      };

      mpv-executable-path = lib.mkOption {
        type = lib.types.str;
        default = lib.getExe cfg.mpvPackage;
        defaultText = lib.literalExpression ''
          lib.getExe config.services.greg-ng.mpvPackage
        '';
        description = ''
          Path to the mpv executable.
        '';
      };

      mpv-config-file = lib.mkOption {
        type = with lib.types; nullOr str;
        default = null;
        description = ''
          Path to the mpv config file.
        '';
      };

      auto-start-mpv = lib.mkOption {
        type = lib.types.bool;
        default = true;
        description = ''
          Whether to automatically start mpv.
        '';
      };

      force-auto-start = lib.mkOption {
        type = lib.types.bool;
        default = true;
        description = ''
          Whether to force auto starting mpv.
        '';
      };
    };
  };

  config = {
    users.users."greg".isNormalUser = true;

    systemd.user.services.greg-ng = {
      description = "greg-ng, an mpv based media player";
      wantedBy = [ "graphical.target" ];
      serviceConfig = {
        User = "greg";
        ExecStart = ''
          ${pkgs.writeShellScript "greg-ng" ''
            ${lib.getExe cfg.package} ${lib.cli.toGNUCommandLineShell { } cfg.settings}
          ''}
        '';
        Restart = "always";
      };
    };
  };
}