swaync: factor out a "service-dispatcher"

hosts/common/programs/swaynotificationcenter/buttons.nix

@@ -1,91 +1,23 @@
 { pkgs }:
 let
-  # TODO: move ALL of the scripts into just one helper.
-  systemctl-toggle' = pkgs.writeShellApplication {
-    name = "systemctl-toggle";
-    runtimeInputs = [
-      pkgs.systemd
-    ];
-    text = ''
-      if systemctl is-active "$@"; then
-        systemctl stop "$@"
-      else
-        systemctl start "$@"
-      fi
-    '';
-  };
-  systemctl-toggle = "${systemctl-toggle'}/bin/systemctl-toggle";
-
-  print-systemd-active' = pkgs.writeShellApplication {
-    name = "print-systemd-active";
-    runtimeInputs = [
-      pkgs.systemd
-    ];
-    text = ''
-      if systemctl is-active "$@"; then
-        echo true
-      else
-        echo false
-      fi
-    '';
-  };
-  print-systemd-active = "${print-systemd-active'}/bin/print-systemd-active";
-
-  s6-toggle' = pkgs.writeShellApplication {
-    name = "s6-toggle";
-    runtimeInputs = [
-      pkgs.s6
-      pkgs.s6-rc
-    ];
-    text = ''
-      service="$1"
-      if [ "$(s6-svstat -o wantedup "$XDG_RUNTIME_DIR/s6/live/servicedirs/$service")" = "true" ]; then
-        s6-rc stop "$service"
-      else
-        s6-rc start "$service"
-      fi
-    '';
-  };
-  s6-toggle = "${s6-toggle'}/bin/s6-toggle";
-
-  print-s6-active' = pkgs.writeShellApplication {
-    name = "print-s6-active";
-    runtimeInputs = [
-      pkgs.s6
-    ];
-    text = ''
-      # s6-svstat's native output is "true"/"false" as expected by swaync
-      s6-svstat -o wantedup "$XDG_RUNTIME_DIR/s6/live/servicedirs/$1"
-    '';
-  };
-  print-s6-active = "${print-s6-active'}/bin/print-s6-active";
-
-  systemServiceButton = name: label: {
-    # XXX: this is surely broken, due to sandboxing/perms
+  serviceButton = svcType: name: label: {
     inherit label;
     type = "toggle";
-    command = "/run/wrappers/bin/sudo ${systemctl-toggle} ${name}";
-    update-command = "${print-systemd-active} ${name}.service";
-    active = true;
-  };
-  userServiceButton = name: label: {
-    inherit label;
-    type = "toggle";
-    command = "${s6-toggle} ${name}";
-    update-command = "${print-s6-active} ${name}";
+    command = "swaync-service-dispatcher toggle ${svcType} ${name}";
+    update-command = "swaync-service-dispatcher print ${svcType} ${name}";
     active = true;
   };
 in
 {
-  gps = systemServiceButton "eg25-control-gps" "";  # GPS services; other icons: gps, ⌖, 🛰, 🌎, 
-  cell-modem = systemServiceButton "eg25-control-powered" "󰺐";  # icons: 5g, 📡, 📱, ᯤ, ⚡, , 🌐, 📶, 🗼, 󰀂, , 󰺐, 󰩯
-  vpn = systemServiceButton "wg-quick-vpn-servo" "vpn::hn";
+  gps = serviceButton "systemd" "eg25-control-gps" "";  # GPS services; other icons: gps, ⌖, 🛰, 🌎, 
+  cell-modem = serviceButton "systemd" "eg25-control-powered" "󰺐";  # icons: 5g, 📡, 📱, ᯤ, ⚡, , 🌐, 📶, 🗼, 󰀂, , 󰺐, 󰩯
+  vpn = serviceButton "systemd" "wg-quick-vpn-servo" "vpn::hn";
 
-  gnome-calls = userServiceButton "gnome-calls" "SIP";
-  geary = userServiceButton "geary" "󰇮";  # email (Geary); other icons: ✉, [E], 📧, 󰇮
-  abaddon = userServiceButton "abaddon" "󰊴";  # Discord chat client; icons: 󰊴, 🎮
-  dissent = userServiceButton "dissent" "󰊴";  # Discord chat client; icons: 󰊴, 🎮
-  signal-desktop = userServiceButton "signal-desktop" "💬";  # Signal messenger; other icons: 󰍦
-  dino = userServiceButton "dino" "XMPP";  # XMPP calls (jingle)
-  fractal = userServiceButton "fractal" "[m]";  # Matrix messages
+  gnome-calls = serviceButton "s6" "gnome-calls" "SIP";
+  geary = serviceButton "s6" "geary" "󰇮";  # email (Geary); other icons: ✉, [E], 📧, 󰇮
+  abaddon = serviceButton "s6" "abaddon" "󰊴";  # Discord chat client; icons: 󰊴, 🎮
+  dissent = serviceButton "s6" "dissent" "󰊴";  # Discord chat client; icons: 󰊴, 🎮
+  signal-desktop = serviceButton "s6" "signal-desktop" "💬";  # Signal messenger; other icons: 󰍦
+  dino = serviceButton "s6" "dino" "XMPP";  # XMPP calls (jingle)
+  fractal = serviceButton "s6" "fractal" "[m]";  # Matrix messages
 }

hosts/common/programs/swaynotificationcenter/default.nix

@@ -21,6 +21,18 @@ let
   scripts = import ./scripts.nix { inherit pkgs; };
 in
 {
+  sane.programs.swaync-service-dispatcher = {
+    packageUnwrapped = pkgs.static-nix-shell.mkBash {
+      pname = "swaync-service-dispatcher";
+      srcRoot = ./.;
+      pkgs = [
+        "s6"
+        "s6-rc"
+        "systemd"
+      ];
+    };
+  };
+
   sane.programs.swaynotificationcenter = {
     configOption = with lib; mkOption {
       type = types.submodule {
@@ -77,7 +89,10 @@ in
     # the glib code which consumes this is `g_notification_backend_new_default`, calling into `_g_io_module_get_default_type`.
     env.GNOTIFICATION_BACKEND = "freedesktop";
 
-    suggestedPrograms = [ "feedbackd" ];
+    suggestedPrograms = [
+      "feedbackd"
+      "swaync-service-dispatcher"  #< used when toggling buttons
+    ];
 
     fs.".config/swaync/style.css".symlink.target = ./style.css;
     fs.".config/swaync/config.json".symlink.text = builtins.toJSON {

hosts/common/programs/swaynotificationcenter/swaync-service-dispatcher

@@ -0,0 +1,53 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash -p s6 -p s6-rc -p systemd
+
+action="$1"
+type="$2"
+service="$3"
+
+checkActive() {
+  case "$type" in
+    systemd)
+      systemctl is-active "$service.service" > /dev/null && echo true || echo false
+      ;;
+    s6)
+      s6-svstat -o wantedup "$XDG_RUNTIME_DIR/s6/live/servicedirs/$service"
+      ;;
+  esac
+}
+startService() {
+  case "$type" in
+    systemd)
+      /run/wrappers/bin/sudo systemctl start "$service"
+      ;;
+    s6)
+      s6-rc start "$service"
+      ;;
+  esac
+}
+stopService() {
+  case "$type" in
+    systemd)
+      /run/wrappers/bin/sudo systemctl stop "$service"
+      ;;
+    s6)
+      s6-rc stop "$service"
+      ;;
+  esac
+}
+
+case "$action" in
+  print)
+    checkActive
+    ;;
+  toggle)
+    case "$(checkActive)" in
+      false)
+        stopService
+        ;;
+      true)
+        startService
+        ;;
+    esac
+    ;;
+esac