From 6e5e63157d5aa0f5d69c2afd0ac030edfce12599 Mon Sep 17 00:00:00 2001
From: avionicharshit-byte <harshitavionic@gmail.com>
Date: Sun, 30 Aug 2026 00:50:17 +0530
Subject: [PATCH] fix(common): don't drop device overrides when the user agent
 looks like a server

---
 .../common/server/parser-user-agent.test.ts   | 37 +++++++++++++++++++
 packages/common/server/parser-user-agent.ts   | 14 ++++++-
 2 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/packages/common/server/parser-user-agent.test.ts b/packages/common/server/parser-user-agent.test.ts
index 917f8566b..888fcd9f0 100644
--- a/packages/common/server/parser-user-agent.test.ts
+++ b/packages/common/server/parser-user-agent.test.ts
@@ -128,6 +128,43 @@ describe('parseUserAgent', () => {
       model: 'Custom Model',
     });
   });
+
+  it('should apply overrides on a non-browser sdk user agent', () => {
+    // A native SDK sends a plain name/version UA, which the server heuristic
+    // matches, but it also states what the device is. The overrides win.
+    const ua = 'my-sdk/1.0.0';
+    const overrides = {
+      __os: 'Android',
+      __osVersion: '13',
+      __device: 'mobile',
+      __brand: 'Acme',
+      __model: 'A105',
+    };
+
+    expect(parseUserAgent(ua, overrides)).toEqual({
+      isServer: false,
+      device: 'mobile',
+      os: 'Android',
+      osVersion: '13',
+      browser: undefined,
+      browserVersion: undefined,
+      brand: 'Acme',
+      model: 'A105',
+    });
+  });
+
+  it('should still be a server when a non-browser user agent sends no device overrides', () => {
+    expect(parseUserAgent('my-sdk/1.0.0', { __ip: '1.2.3.4' })).toEqual({
+      isServer: true,
+      device: 'server',
+      os: '',
+      osVersion: '',
+      browser: '',
+      browserVersion: '',
+      brand: '',
+      model: '',
+    });
+  });
 });
 
 describe('getDevice', () => {
diff --git a/packages/common/server/parser-user-agent.ts b/packages/common/server/parser-user-agent.ts
index c859bccb2..783ba5c4a 100644
--- a/packages/common/server/parser-user-agent.ts
+++ b/packages/common/server/parser-user-agent.ts
@@ -247,7 +247,10 @@ export function parseUserAgent(
   if (!ua) return parsedServerUa;
   const res = parse(ua);
 
-  if (isServer(res)) {
+  // A native SDK sends a plain name/version UA, which the server heuristic
+  // matches, but it also states what device it is running on. Trust that over
+  // the heuristic, otherwise the overrides are silently dropped.
+  if (isServer(res) && !hasDeviceOverrides(overrides)) {
     return parsedServerUa;
   }
 
@@ -287,6 +290,15 @@ export function parseUserAgent(
   } as const;
 }
 
+const DEVICE_OVERRIDE_KEYS = ['__os', '__device', '__brand', '__model'] as const;
+
+function hasDeviceOverrides(overrides?: Record<string, unknown>) {
+  if (!overrides) return false;
+  return DEVICE_OVERRIDE_KEYS.some(
+    (key) => typeof overrides[key] === 'string' && overrides[key] !== '',
+  );
+}
+
 function isServer(res: UAParser.IResult) {
   // Matches user agents like "Go-http-client/1.0" or "Go Http Client/1.0"
   // It should just match the first name (with optional spaces) and version