From f09f3b75ccbaa85e2b0624c3211ec478d6e845c5 Mon Sep 17 00:00:00 2001
From: robbond <rob@rdbsolutions.co.uk>
Date: Mon, 23 Mar 2026 17:01:03 +0000
Subject: [PATCH] TASK22224: fix downloadblob path normalization for prefixed
 blob names

---
 pages/api/file/downloadblob.js | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/pages/api/file/downloadblob.js b/pages/api/file/downloadblob.js
index e3cc0ff0..3973d93a 100644
--- a/pages/api/file/downloadblob.js
+++ b/pages/api/file/downloadblob.js
@@ -49,17 +49,24 @@ ApiProxy.get(async (req, res) => {
     }
 
     try {
-        const bloblocation =
-            casefolderID + (blobName.indexOf(".json") > 0 ? "/" : "/files/");
+        const decodedBlobName = decodeURI(blobName);
+        const normalizedBlobName = decodedBlobName.startsWith(
+            casefolderID + "/"
+        )
+            ? decodedBlobName
+            : casefolderID +
+              (decodedBlobName.indexOf(".json") > 0 ? "/" : "/files/") +
+              decodedBlobName;
 
         const downloaded = await downloadFile(
             containerName,
-            bloblocation + decodeURI(blobName)
+            normalizedBlobName
         );
+        const responseFileName = decodedBlobName.split("/").pop();
 
         res.setHeader(
             "content-disposition",
-            "attachment; filename=" + decodeURI(blobName)
+            "attachment; filename=" + responseFileName
         );
         return res.status(200).send(downloaded);
     } catch (error) {