From 8304388d299de608cbb87b6bfb0e46447af4f8ce Mon Sep 17 00:00:00 2001
From: Brandon Doornbos <41441504+brandon-doornbos@users.noreply.github.com>
Date: Wed, 17 Jun 2026 01:47:39 +0200
Subject: [PATCH] Properly handle on disk changes

Follows Collabora spec:
https://sdk.collaboraonline.com/docs/advanced_integration.html#detecting-external-document-change
---
 copyparty/httpcli.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/copyparty/httpcli.py b/copyparty/httpcli.py
index c162ead7..fbf21927 100644
--- a/copyparty/httpcli.py
+++ b/copyparty/httpcli.py
@@ -3499,6 +3499,11 @@ class HttpCli(object):
             if self.do_log:
                 self.log("WOPI POST 'contents': %s" % (full_path))
 
+            last_mod_time = time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime(os.path.getmtime(full_path)))
+            if self.headers["x-cool-wopi-timestamp"] != last_mod_time:
+                self.reply(json.dumps({"COOLStatusCode": 1010}).encode("utf-8"), 409)
+                return True
+
             reader, _ = self.get_body_reader()
             buf = b""
             for rbuf in reader:
@@ -3510,11 +3515,11 @@ class HttpCli(object):
                 with open(full_path, "wb") as file:
                     file.write(buf)
 
-                mod_time = {
+                new_mod_time = {
                     "LastModifiedTime": 
                         time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime(os.path.getmtime(full_path)))
                 }
-                ret = json.dumps(mod_time).encode("utf-8", "replace")
+                ret = json.dumps(new_mod_time).encode("utf-8", "replace")
                 self.reply(ret, 200, "application/json; charset=utf-8")
                 return True