sway.nix

{ config, lib, pkgs, ...}:

with lib;

let
  cfg = config.services.wayland.windowManager.sway;
in

{
  ### Interface
  options = {
    services.wayland.windowManager.sway = {
      enable = mkEnableOption "Sway window manager";

      configFile = mkOption {
        default = null;
        type = with types; nullOr path;
        description =
        ''
          Location of the Sway configuration file.
        '';
      };
    };
  };

  ### Implementation

  config = mkIf cfg.enable {
    services.wayland.windowManager.session = [{
      name = "sway";
      start =
      ''
        ${pkgs.sway}/bin/sway ${optionalString (cfg.configFile != null)
        "-c \"${cfg.configFile}\""
      } & waitPID=$!
      '';

    }];

    environment.systemPackages = [ pkgs.sway ];

  };
}