Fix up swayidle config

alex/sway.nix

@@ -207,15 +207,54 @@ in
     };
   };
 
-  services.swayidle = {
+  services.swayidle =
+    let
+    lock = "${pkgs.swaylock-effects}/bin/swaylock --daemonize";
+    # modify "display" function based on your window manager
+    # Sway
+    display = status: "${pkgs.sway}/bin/swaymsg 'output * power ${status}'";
+    # Niri
+    # display = status: "${pkgs.niri}/bin/niri msg action power-${status}-monitors";
+  in
+  {
     enable = true;
     timeouts = [
-      { timeout = 300; command = "swaylock -f"; }
-      { timeout = 600; command = "swaymsg \"output * dpms off\""; resumeCommand = "swaymsg \"output * dpms on\""; }
-      { timeout = 900; command = "systemctl suspend"; }
+    {
+      timeout = 295; # in seconds
+      command = "${pkgs.libnotify}/bin/notify-send 'Locking in 5 seconds' -t 5000";
+    }
+    {
+      timeout = 300;
+      command = lock;
+    }
+    {
+      timeout = 330;
+      command = display "off";
+      resumeCommand = display "on";
+    }
+    {
+      timeout = 600;
+      command = "${pkgs.systemd}/bin/systemctl suspend";
+    }
     ];
     events = [
-      { event = "before-sleep"; command = "swaylock -f"; }
+    {
+      event = "before-sleep";
+      # adding duplicated entries for the same event may not work
+      command = (display "off") + "; " + lock;
+    }
+    {
+      event = "after-resume";
+      command = display "on";
+    }
+    {
+      event = "lock";
+      command = (display "off") + "; " + lock;
+    }
+    {
+      event = "unlock";
+      command = display "on";
+    }
     ];
   };