Add hinernation on low battery feature

home/battery/default.nix

@@ -1,46 +1,55 @@
 { config, pkgs, ... }:
 
 let
-  batteryNotify = pkgs.writeShellScript "battery-notify" ''
+  battery = pkgs.writeShellScript "battery" ''
     BAT="/sys/class/power_supply/BAT1"
     LEVEL=$(cat "$BAT/capacity")
     STATUS=$(cat "$BAT/status")
 
-    if [ "$STATUS" = "Discharging" ] && [ "$LEVEL" -lt 20 ]; then
+    has_notifications() {
-      ${pkgs.dunst}/bin/dunstify \
+      ${pkgs.dbus}/bin/busctl --user status org.freedesktop.Notifications >/dev/null 2>&1
-        -r 9991 \
+    }
-        -t 0 \
+
-        -u critical \
+    if [ "$STATUS" = "Discharging" ] && [ "$LEVEL" -lt 3 ]; then
-        "Battery Low" \
+      ${pkgs.systemd}/bin/systemctl hibernate
-        "Battery is at ''${LEVEL}%"
+      exit 0
-    else
+    fi
-      ${pkgs.dunst}/bin/dunstify \
+
-        -C 9991 2>/dev/null || true
+    if has_notifications; then
+      if [ "$STATUS" = "Discharging" ] && [ "$LEVEL" -lt 20 ]; then
+        ${pkgs.dunst}/bin/dunstify \
+          -r 9991 \
+          -t 0 \
+          -u critical \
+          "Battery Low" \
+          "Battery is at ''${LEVEL}%"
+      else
+        ${pkgs.dunst}/bin/dunstify \
+          -C 9991 2>/dev/null || true
+      fi
     fi
   '';
 in
 {
-  systemd.user.services.battery-notify = {
+  systemd.user.services.battery = {
     Unit = {
-      Description = "Low battery notification";
+      Description = "Battery management";
-      After = [ "dunst.service" ];
-      Requires = [ "dunst.service" ];
     };
 
     Service = {
       Type = "oneshot";
-      ExecStart = batteryNotify;
+      ExecStart = battery;
     };
   };
 
-  systemd.user.timers.battery-notify = {
+  systemd.user.timers.battery = {
     Unit = {
-      Description = "Check battery level every 20 seconds";
+      Description = "Check battery level every 15 seconds";
     };
 
     Timer = {
-      OnBootSec = "20s";
+      OnBootSec = "15s";
-      OnUnitActiveSec = "20s";
+      OnUnitActiveSec = "15s";
     };
 
     Install = {