{
  pkgs,
  config,
  lib,
  ...
}:
let
  inherit (config.grimmShared) enable sway screens;
  inherit (lib)
    types
    mkOption
    mkEnableOption
    mapAttrsToList
    optionalString
    concatMapStrings
    isInt
    min
    max
    foldl'
    getExe
    getExe'
    isPath
    isDerivation
    concatLines
    optional
    mkIf
    ;
  inherit (pkgs) writeShellScriptBin;

  sway_conf = types.submodule (
    { ... }:
    {
      options = {
        keybinds = mkOption {
          type = types.attrsOf types.str;
          default = { };
          description = "set of keybinds assigning key combo to action";
        };

        autolaunch = mkOption {
          type = types.listOf (types.either types.nonEmptyStr types.package);
          default = [ ];
          description = "set of commands to be run at sway startup";
        };

        execAlways = mkOption {
          type = types.listOf (types.either types.nonEmptyStr types.package);
          default = [ ];
          description = "set of commands to be run at sway reload";
        };

        extraConfig = mkOption {
          type = types.str;
          default = "";
          description = "additional sway config to be included";
        };

        definitions = mkOption {
          type = types.attrsOf types.str;
          default = { };
          description = "set of definitions assigning variable to value";
        };

        modes = mkOption {
          type = types.attrsOf sway_conf;
          default = { };
          description = "possible modes to switch to, e.g. resize";
        };
      };
    }
  );

  build_screen_def =
    fps_func:
    let
      output_def = mapAttrsToList (
        name: value:
        "output ${value.id} mode ${value.mode}@${toString (fps_func value.fps)}Hz"
        + (optionalString (value.pos != null) " position ${value.pos}")
      ) screens;
    in
    ''
      for pid in $(${getExe' pkgs.procps "pgrep"} sway -x)
      do
        uid=$(id -u $(${getExe' pkgs.procps "ps"} -o user= -p $pid))
        export SWAYSOCK="/run/user/$uid/sway-ipc.$uid.$pid.sock"
        if [[ -e "$SWAYSOCK" ]] ; then
          echo "sock is $SWAYSOCK"
          ${getExe' config.programs.sway.package "swaymsg"} '${concatMapStrings (s: s + " ; ") output_def}'
        fi
      done
    '';

  fps_min = fps: if isInt fps then fps else (foldl' min 2147483647 fps);
  fps_max = fps: if isInt fps then fps else (foldl' max 0 fps);
  init_screens_min_fps = writeShellScriptBin "init-screens-min" (build_screen_def fps_min);
  init_screens_max_fps = writeShellScriptBin "init-screens-max" (build_screen_def fps_max);
  init_screens_auto = writeShellScriptBin "init-screens-auto" "which run-on-ac && which run-on-bat && run-on-ac ${getExe init_screens_max_fps} && run-on-bat ${getExe init_screens_min_fps}  || ${getExe init_screens_max_fps}";
in
{
  config =
    let
      bar_conf_file =
        if (isPath sway.bar.config) then
          sway.bar.config
        else
          pkgs.writers.writeJSON "config.json" sway.bar.config;
      waybar_full = writeShellScriptBin "waybar-full" (
        (getExe config.programs.waybar.package)
        + (optionalString (!isNull sway.bar.config) " -c ${bar_conf_file}")
        + (optionalString (!isNull sway.bar.style) " -s ${sway.bar.style}")
      );

      bar_config = ''
        bar { 
              swaybar_command ${getExe waybar_full}
        }
      '';

      dbus-sway-environment = pkgs.writeShellScriptBin "dbus-sway-environment" ''
        dbus-update-activation-environment --systemd WAYLAND_DISPLAY XDG_CURRENT_DESKTOP=sway
        systemctl --user stop xdg-desktop-portal xdg-desktop-portal-wlr
        systemctl --user start xdg-desktop-portal xdg-desktop-portal-wlr
      '';

      build_conf =
        sway_conf:
        let
          build_definition_lines = mapAttrsToList (name: value: "set \$${name} ${value}");
          build_keybind_lines = mapAttrsToList (key: value: "bindsym ${key} ${value}");
          build_exec_lines = e: map (item: "${e} " + (if isDerivation item then (getExe item) else item));
          build_mode_lines = mapAttrsToList (
            name: value: ''
              mode "${name}" {
              ${concatLines (map (item: "    " + item) (build_conf value))}}''
          );
        in
        (
          [ ]
          ++ (build_definition_lines sway_conf.definitions)
          ++ (build_keybind_lines sway_conf.keybinds)
          ++ (build_exec_lines "exec_always" sway_conf.execAlways)
          ++ (build_exec_lines "exec" sway_conf.autolaunch)
          ++ (build_mode_lines sway_conf.modes)
          ++ optional (sway_conf.extraConfig != "") sway_conf.extraConfig
        );

      sway_conf = concatLines (
        (build_conf sway.config)
        ++ optional sway.bar.enable bar_config
        ++ (mapAttrsToList (
          name: value:
          "output ${value.id} mode ${value.mode}"
          + (optionalString (value.pos != null) " position ${value.pos}")
        ) screens)
      );

      conf_path = "sway.conf";
    in
    mkIf (enable && sway.enable) {
      environment.etc."${conf_path}".text = sway_conf;

      grimmShared.sway.config.execAlways = [
        dbus-sway-environment
        init_screens_auto
      ];

      environment.systemPackages =
        [
          waybar_full
          dbus-sway-environment
          init_screens_min_fps
          init_screens_max_fps
          init_screens_auto
        ]
        ++ (with pkgs; [
          procps
          slurp
          libnotify
        ]);

      systemd.services.reload-sway = {
        description = "Reload all running sway instances";
        wantedBy = [ "multi-user.target" ];

        serviceConfig.Type = "oneshot";
        script = ''
          for pid in $(${getExe' pkgs.procps "pgrep"} sway -x)
          do
            uid=$(id -u $(${getExe' pkgs.procps "ps"} -o user= -p $pid))
            export SWAYSOCK="/run/user/$uid/sway-ipc.$uid.$pid.sock"
            if [[ -e "$SWAYSOCK" ]] ; then
              echo "sock is $SWAYSOCK"
              ${getExe' config.programs.sway.package "swaymsg"} reload
            fi
          done

          rm -rf /home/*/.cache/rmenu
        '';
        reloadTriggers = [ config.environment.etc."${conf_path}".source ];
      };

      # programs.waybar.enable = true;

      programs.dconf.enable = true;

      programs.sway = {
        enable = true;

        wrapperFeatures = {
          gtk = true;
          base = true;
        };

        extraPackages = with pkgs; [
#          swaylock
          swayidle
          wl-clipboard
          wf-recorder
          dmenu
          wmenu
          waybar-mpris
        ];
        extraOptions = [
          "--config"
          "/etc/${conf_path}"
        ];
        extraSessionCommands = ''
          # source /etc/profile
          # test -f $HOME/.profile && source $HOME/.profile
          systemctl --user import-environment

          export XDG_CURRENT_DESKTOP=sway
          export SDL_VIDEODRIVER=wayland
          export QT_QPA_PLATFORM=wayland
          export QT_WAYLAND_DISABLE_WINDOWDECORATION="1"
          export _JAVA_AWT_WM_NONREPARENTING=1
          export MOZ_ENABLE_WAYLAND=1
          # export WLR_RENDERER=vulkan
          # export DRI_PRIME=1
          export NIXOS_OZONE_WL=1
        '';
      };
    };

  options.grimmShared.sway = {
    enable = mkEnableOption "grimm-sway";

    bar = {
      enable = mkEnableOption "grimm-sway-bar";

      style = mkOption {
        type = types.nullOr types.path;
        default = null;
        description = "waybar style sheet to use";
      };

      config = mkOption {
        type = types.nullOr (types.either types.path types.attrs);
        default = null;
        description = "waybar config to use";
      };
    };

    config = mkOption {
      type = sway_conf;
      description = "sway config to use";
    };
  };
}