refactor: split greetd and regreet, use seatd

hosts/atlas/default.nix

@@ -14,7 +14,7 @@
     ../common/users/gabriel
 
     ../common/optional/peripherals.nix
-    ../common/optional/greetd.nix
+    ../common/optional/regreet.nix
     ../common/optional/pipewire.nix
     ../common/optional/quietboot.nix
     ../common/optional/wireless.nix

hosts/common/global/default.nix

@@ -27,6 +27,7 @@
       ./prometheus-node-exporter.nix
       ./kdeconnect.nix
       ./upower.nix
+      ./display-manager.nix
     ]
     ++ (builtins.attrValues outputs.nixosModules);
 

hosts/common/global/display-manager.nix

@@ -0,0 +1,14 @@
+{config, lib, ...}: {
+  users.users.greeter = {
+    extraGroups = ["seat"];
+  };
+  services = {
+    seatd.enable = true;
+    greetd.enable = true;
+    displayManager = {
+      enable = true;
+      # Export user sessions to system
+      sessionPackages = lib.flatten (lib.mapAttrsToList (_: v: v.home.exportedSessionPackages) config.home-manager.users);
+    };
+  };
+}

hosts/common/optional/regreet.nix

@@ -1,13 +1,5 @@
-{
-  lib,
-  config,
-  pkgs,
-  ...
-}: {
-  services.displayManager = {
-    enable = true;
-    sessionPackages = lib.flatten (lib.mapAttrsToList (_: v: v.home.exportedSessionPackages) config.home-manager.users);
-  };
+# Graphical greeter, hooks into greetd
+{pkgs, ...}: {
   programs.regreet = {
     enable = true;
     cageArgs = ["-s" "-m" "last"];
@@ -30,10 +22,6 @@
     };
   };
 
-  services.greetd = {
-    enable = true;
-  };
-
   environment.persistence = {
     # Persist last user and last selected session
     "/persist".directories = [{

hosts/maia/default.nix

@@ -13,7 +13,7 @@
     ../common/users/gabriel
 
     ../common/optional/peripherals.nix
-    ../common/optional/greetd.nix
+    ../common/optional/regreet.nix
     ../common/optional/pipewire.nix
     ../common/optional/quietboot.nix
 

hosts/pleione/default.nix

@@ -14,7 +14,7 @@
 
     ../common/optional/pipewire.nix
     ../common/optional/quietboot.nix
-    ../common/optional/greetd.nix
+    ../common/optional/regreet.nix
 
     ./steam.nix
     ./jellyfin-kiosk.nix