nixos/wireplumber: add required lv2 plugins to service path

          `share/wireplumber/*/*.lua` files.

        '';

      };

      extraLv2Packages = lib.mkOption {

        type = lib.types.listOf lib.types.package;

        default = [];

        example = lib.literalExpression "[ pkgs.lsp-plugins ]";

        description = lib.mdDoc ''

          List of packages that provide LV2 plugins in `lib/lv2` that should

          be made available to WirePlumber for [filter chains][wiki-filter-chain].

          Config packages have their required LV2 plugins added automatically,

          so they don't need to be specified here.

          [wiki-filter-chain]: https://docs.pipewire.org/page_module_filter_chain.html

        '';

      };

    };

  };

  config =

    let

      configPackages = cfg.configPackages;

      pwNotForAudioConfigPkg = pkgs.writeTextDir "share/wireplumber/main.lua.d/80-pw-not-for-audio.lua" ''

        -- PipeWire is not used for audio, so prevent it from grabbing audio devices

        alsa_monitor.enable = function() end

        bluez_monitor.properties["with-logind"] = false

      '';

      configs = pkgs.buildEnv {

        name = "wireplumber-configs";

        paths = configPackages

      configPackages = cfg.configPackages

          ++ lib.optional (!pwUsedForAudio) pwNotForAudioConfigPkg

          ++ lib.optionals config.services.pipewire.systemWide [ systemwideConfigPkg systemwideBluetoothConfigPkg ];

      configs = pkgs.buildEnv {

        name = "wireplumber-configs";

        paths = configPackages;

        pathsToLink = [ "/share/wireplumber" ];

      };

      requiredLv2Packages = lib.flatten

        (

          lib.concatMap

            (p:

              lib.attrByPath ["passthru" "requiredLv2Packages"] [] p

            )

            configPackages

        );

      lv2Plugins = pkgs.buildEnv {

        name = "wireplumber-lv2-plugins";

        paths = cfg.extraLv2Packages ++ requiredLv2Packages;

        pathsToLink = [ "/lib/lv2" ];

      };

    in

    lib.mkIf cfg.enable {

      assertions = [

      systemd.services.wireplumber.environment = lib.mkIf config.services.pipewire.systemWide {

        # Force WirePlumber to use system dbus.

        DBUS_SESSION_BUS_ADDRESS = "unix:path=/run/dbus/system_bus_socket";

        LV2_PATH = "${lv2Plugins}/lib/lv2";

      };

      systemd.user.services.wireplumber.environment.LV2_PATH =

        lib.mkIf (!config.services.pipewire.systemWide) "${lv2Plugins}/lib/lv2";

    };

}