Configure power actions with logind

This configures what happens on lid close (on battery / on AC) and
control what happens on the power button press.

system/roles/workstation/services/default.nix

@@ -4,6 +4,7 @@
     ./mount.nix
     ./printing.nix
     ./misc.nix
+    ./logind.nix
     ./gnome-keyring.nix
   ];
 }

system/roles/workstation/services/logind.nix

@@ -0,0 +1,18 @@
+{lib, config, ...}: let
+  inherit (lib) mkIf;
+  deviceType = config.myOptions.device.roles.type;
+  acceptedTypes = ["laptop" "desktop"];
+in {
+  config = mkIf (builtins.elem deviceType acceptedTypes) {
+    # despite being under logind, this has nothing to do with login
+    # it's about power management
+    services.logind = {
+      lidSwitch = "suspend-then-hibernate";
+      lidSwitchExternalPower = "lock";
+      extraConfig = ''
+        HandlePowerKey=suspend-then-hibernate
+        HibernateDelaySec=3600
+      '';
+    };
+  };
+}