fix: Use MTDeviceCreateList to register callbacks on all multitouch devices

MTDeviceCreateDefault() may not return the correct device on some Macs,
particularly with macOS 26.1 beta. Using MTDeviceCreateList() to enumerate
all available multitouch devices and registering callbacks on each one
ensures touch events are properly received.

Author: NullPointerDepressiveDisorder

MiddleDrag/Core/MultitouchFramework.swift

@@ -29,6 +29,10 @@ typealias MTContactCallbackFunction = @convention(c) (
 @_silgen_name("MTDeviceCreateDefault")
 func MTDeviceCreateDefault() -> MTDeviceRef?
 
+/// Get list of all multitouch devices
+@_silgen_name("MTDeviceCreateList")
+func MTDeviceCreateList() -> CFArray?
+
 // MARK: - Device Control
 
 /// Start the multitouch device

MiddleDrag/Managers/DeviceMonitor.swift

@@ -1,6 +1,27 @@
 import Foundation
 import CoreFoundation
 
+// MARK: - Debug Logging
+
+private let debugLogPath = FileManager.default.homeDirectoryForCurrentUser.appendingPathComponent("middledrag_touch.log")
+private var touchCount = 0
+
+private func logToFile(_ message: String) {
+    let timestamp = ISO8601DateFormatter().string(from: Date())
+    let line = "[\(timestamp)] \(message)\n"
+    if let data = line.data(using: .utf8) {
+        if FileManager.default.fileExists(atPath: debugLogPath.path) {
+            if let handle = try? FileHandle(forWritingTo: debugLogPath) {
+                handle.seekToEndOfFile()
+                handle.write(data)
+                handle.closeFile()
+            }
+        } else {
+            try? data.write(to: debugLogPath)
+        }
+    }
+}
+
 // MARK: - Global Callback Storage
 
 // Required because C callbacks cannot capture Swift context
@@ -9,6 +30,11 @@ private var gDeviceMonitor: DeviceMonitor?
 // MARK: - C Callback Function
 
 private let deviceContactCallback: MTContactCallbackFunction = { device, touches, numTouches, timestamp, frame in
+    touchCount += 1
+    if touchCount <= 5 || touchCount % 100 == 0 {
+        logToFile("Touch callback #\(touchCount): \(numTouches) touches")
+    }
+    
     guard let monitor = gDeviceMonitor,
           let touches = touches else { return 0 }
 
@@ -53,17 +79,44 @@ class DeviceMonitor {
     func start() {
         guard !isRunning else { return }
 
-        guard let defaultDevice = MultitouchFramework.shared.getDefaultDevice() else {
-            print("⚠️ No multitouch device found")
-            return
-        }
+        logToFile("DeviceMonitor.start() called")
 
-        device = defaultDevice
+        // Try to get all devices
+        if let deviceList = MTDeviceCreateList() {
+            let count = CFArrayGetCount(deviceList)
+            logToFile("Found \(count) multitouch device(s)")
+            
+            for i in 0..<count {
+                let devicePtr = CFArrayGetValueAtIndex(deviceList, i)
+                if let dev = devicePtr {
+                    let deviceRef = UnsafeMutableRawPointer(mutating: dev)
+                    logToFile("Registering callback for device \(i): \(deviceRef)")
+                    MTRegisterContactFrameCallback(deviceRef, deviceContactCallback)
+                    MTDeviceStart(deviceRef, 0)
+                    
+                    if device == nil {
+                        device = deviceRef
+                    }
+                }
+            }
+        } else {
+            logToFile("MTDeviceCreateList returned nil, trying default")
+        }
 
-        MTRegisterContactFrameCallback(defaultDevice, deviceContactCallback)
-        MTDeviceStart(defaultDevice, 0)
+        // Also try the default device
+        if let defaultDevice = MultitouchFramework.shared.getDefaultDevice() {
+            logToFile("Also registering default device: \(defaultDevice)")
+            MTRegisterContactFrameCallback(defaultDevice, deviceContactCallback)
+            MTDeviceStart(defaultDevice, 0)
+            
+            if device == nil {
+                device = defaultDevice
+            }
+        }
 
+        logToFile("Device registration complete")
         isRunning = true
+        logToFile("DeviceMonitor started successfully")
     }
 
     /// Stop monitoring