fix: Allow restart with HA fix applied (#289)

Author: ckulka

files/docker-entrypoint.d/30-apply-home-assistant-fix.sh

@@ -9,14 +9,24 @@ then
   exit 0
 fi
 
+# Skip further processing if the current Plugin.php file already has the Home Assistant fix
+CHECKSUM="7a7c9adc36dfc6cf780039d1ff7800df3e5f138a  /var/www/baikal/vendor/sabre/dav/lib/CalDAV/Plugin.php"
+if echo $CHECKSUM | sha1sum --check --status - ;
+then
+  echo "$ME: info: Home Assistant fix already applied"
+  exit 0
+fi
+
 # Abort if the Plugin.php file differs from the packaged version.
-# This means either the user customized the Plugin.php file already, or the
-# packaged version changed and the fix needs to be updated.
+# This means the user customized the Plugin.php file already and applying the 
+# Home Assistant fix would remove any modifications the user did. We inform the
+# user about this, so that they can make the necessary adjustments to their
+# custom Plugin.php file.
 CHECKSUM="22e5ac3311fa112e702363920ce86d90256aacc6  /var/www/baikal/vendor/sabre/dav/lib/CalDAV/Plugin.php"
 if ! echo $CHECKSUM | sha1sum --check --status - ;
 then
-  echo "$ME: info: Plugin.php differs from the packaged version"
-  exit 0
+  echo "$ME: info: Plugin.php differs from the packaged version. It looks like you customized it already, so we won't overwrite it and remove your modifications. Please either revert your own changes, or apply the Home Assistant fix manually to your custom Plugin.php file."
+  exit 1
 fi