flake.nix

@@ -68,5 +68,50 @@
           ) { };
         }
       );
+
+      nixosModules.default =
+        { config, lib, pkgs, ... }:
+        let
+          cfg = config.services.jellyfin-lessons;
+        in
+        {
+          options.services.jellyfin-lessons = {
+            enable = lib.mkEnableOption "Jellyfin Lessons plugin";
+            dataDir = lib.mkOption {
+              type = lib.types.str;
+              default = "/var/lib/jellyfin-lessons";
+              description = "Directory for lessons database";
+            };
+            adminPort = lib.mkOption {
+              type = lib.types.port;
+              default = 3099;
+              description = "Port for admin UI";
+            };
+          };
+
+          config = lib.mkIf cfg.enable {
+            # Copy plugin DLL to Jellyfin plugins directory on jellyfin preStart
+            systemd.services.jellyfin = {
+              preStart = let
+                pluginPkg = self.packages.${pkgs.system}.default;
+              in ''
+                mkdir -p /var/lib/jellyfin/plugins/Lessons
+                cp -f ${pluginPkg}/lib/jellyfin-lessons/*.dll /var/lib/jellyfin/plugins/Lessons/
+              '';
+            };
+
+            # Admin UI as a user systemd service
+            systemd.user.services.jellyfin-lessons-admin = {
+              description = "Jellyfin Lessons Admin UI";
+              after = [ "network.target" ];
+              wantedBy = [ "default.target" ];
+              serviceConfig = {
+                ExecStart = "${pkgs.nodejs}/bin/node ${self}/admin-ui/server.js";
+                Restart = "on-failure";
+                Environment = "PORT=${toString cfg.adminPort}";
+              };
+            };
+          };
+        };
     };
 }