From 7855552e06cdac73f9d705450b55ebc2db40d914 Mon Sep 17 00:00:00 2001
From: Astro <astro@spaceboyz.net>
Date: Mon, 10 Jan 2022 04:14:45 +0100
Subject: [PATCH] lib/autoupdate: don't switch back to configurations without
 autoupdate

---
 lib/autoupdate.nix | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/lib/autoupdate.nix b/lib/autoupdate.nix
index dff05f3e..5c518270 100644
--- a/lib/autoupdate.nix
+++ b/lib/autoupdate.nix
@@ -12,6 +12,12 @@
   };
 
   config = lib.mkIf config.c3d2.autoUpdate {
+    # the presence of this file signifies that the system is
+    # autoupdate-enabled. it is checked to prevent autoupdating back
+    # to a system without autoupdate when deploying with autoupdate
+    # for the first time.
+    environment.etc."autoupdated".text = "";
+
     systemd.services.autoupdate = {
       wantedBy = [ "multi-user.target" ];
       path = with pkgs; [ nixFlakes nettools curl jq ];
@@ -28,8 +34,12 @@
           echo "New system available: $NEW"
           # this should fetch the new system from the binary cache
           nix build --no-link "$NEW"
-          # switch to the new system
-          "$NEW/bin/switch-to-configuration" switch
+          if [ -e "$NEW/sw/etc/autoupdated" ]; then
+            # switch to the new system
+            "$NEW/bin/switch-to-configuration" switch
+          else
+            echo "New system is not yet autoupdated"
+          fi
         else
           echo "No update required"
         fi