From 5b115d27f73e4f9fabd1718ced1133cbacba2775 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Wed, 7 Oct 2026 04:10:06 +0000
Subject: [PATCH] Fix insecure extension check in read_sheet_file

Co-authored-by: Horizontal42 <75383519+Horizontal42@users.noreply.github.com>
---
 src-tauri/src/main.rs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src-tauri/src/main.rs b/src-tauri/src/main.rs
index 9a32958..1668980 100644
--- a/src-tauri/src/main.rs
+++ b/src-tauri/src/main.rs
@@ -938,8 +938,12 @@ fn load_extensions(app: AppHandle) -> Vec<ExtensionScript> {
 }
 
 fn is_sheet_path(path: &str) -> bool {
-    let lower = path.to_lowercase();
-    lower.ends_with(".numi") || lower.ends_with(".sum")
+    std::path::Path::new(path)
+        .extension()
+        .map_or(false, |ext| {
+            let ext = ext.to_string_lossy().to_lowercase();
+            ext == "numi" || ext == "sum"
+        })
 }
 
 /// A sheet handed to us by the OS (file association, second launch): same