moved common out of systems

common/global/snapshot_manager.nix

@@ -0,0 +1,44 @@
+{ inputs, pkgs, lib, config, ... }:
+let
+  cfg = config.services.snapshot_manager;
+in
+{
+  options = {
+    services.snapshot_manager = {
+      enable = lib.mkOption {
+        default = true;
+        example = true;
+        description = "Whether to enable k3s-net.";
+        type = lib.types.bool;
+      };
+      path = lib.mkOption {
+        type = lib.types.path;
+        description = "Path that needs to be updated via git pull";
+        default = ./snapshot_config.toml;
+      };
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    systemd = {
+      services."snapshot_manager" = {
+        description = "ZFS Snapshot Manager";
+        requires = [ "zfs-import.target" ];
+        after = [ "zfs-import.target" ];
+        path = [ pkgs.zfs ];
+        serviceConfig = {
+          Type = "oneshot";
+          ExecStart = "${inputs.system_tools.packages.x86_64-linux.default}/bin/snapshot_manager --config-file='${cfg.path}'";
+        };
+      };
+      timers."snapshot_manager" = {
+        wantedBy = [ "timers.target" ];
+        timerConfig = {
+          OnBootSec = "15m";
+          OnUnitActiveSec = "15m";
+          Unit = "snapshot_manager.service";
+        };
+      };
+    };
+  };
+}