From 57ca67f108051d8867b8161c85b26e537cdac4f4 Mon Sep 17 00:00:00 2001
From: Joshua Rogers <MegaManSec@users.noreply.github.com>
Date: Mon, 17 Aug 2026 20:18:40 +0200
Subject: [PATCH] fix: reply to the legacy PIN request instead of letting the
 pair hang
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`devicePairingPINCodeRequest` logged the request and returned without
calling `replyPINCode`, which the delegate contract requires. Any
peripheral that falls back to legacy PIN pairing sat in `.connecting`
until the 60s pair watchdog fired, every attempt.

Reply with the all-zero PIN legacy HID peripherals use, and only for a
pair this app installed in `pendingPairs` — a request belonging to any
other pair is left alone rather than answered on its behalf.
---
 .../Model/Store/BluetoothPeripheralStore.swift   | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/Magic Switch/Model/Store/BluetoothPeripheralStore.swift b/Magic Switch/Model/Store/BluetoothPeripheralStore.swift
index 3e0b80f..e764102 100644
--- a/Magic Switch/Model/Store/BluetoothPeripheralStore.swift	
+++ b/Magic Switch/Model/Store/BluetoothPeripheralStore.swift	
@@ -1568,7 +1568,21 @@ final class BluetoothPeripheralStore: NSObject, ObservableObject, BluetoothPerip
     else {
       return
     }
-    print("Bluetooth pairing requested a PIN code for \(address)")
+    DispatchQueue.main.async { [weak self] in
+      guard let self = self else { return }
+      guard self.pendingPairs[address] === pair else {
+        print("Ignoring Bluetooth PIN code request for \(address): not our pairing")
+        return
+      }
+      print("Replying to Bluetooth PIN code request for \(address)")
+      // Legacy HID peripherals with no keypad take the all-zero PIN.
+      var code = BluetoothPINCode()
+      let digits = Array("0000".utf8)
+      withUnsafeMutableBytes(of: &code.data) { raw in
+        for (index, byte) in digits.enumerated() { raw[index] = byte }
+      }
+      pair.replyPINCode(digits.count, pinCode: &code)
+    }
   }
 
   /// Selector target for `IOBluetoothDevice.register(forDisconnectNotification:...)`.