HeadphoneKeyEventBluetooth: Listen for Bluetooth device pairing

Register a delegate that gets called when Bluetooth devices are paired
with the Mac.

We now need to determine if the paired device is a pair of headphones
(ideally if we can figure out media remote control capability that would
be helpful), and then connect to them over L2CAP to get AVRCP messages.

The `devicePairingFinished:error:` delegate method was a test. Leaving
it in as a reminder that we also need to implement functionality that
looks for already-connected Bluetooth headphones when DomeKey launches.

2 files changed, 19 insertions, 11 deletions

diff --git a/DomeKey/HeadphoneKeyEventBluetooth.h b/DomeKey/HeadphoneKeyEventBluetooth.h
index 86e0ce7..a55a539 100644
--- a/DomeKey/HeadphoneKeyEventBluetooth.h
+++ b/DomeKey/HeadphoneKeyEventBluetooth.h
@@ -7,11 +7,12 @@
 //
 
 #import <Foundation/Foundation.h>
+#import <IOBluetooth/IOBluetooth.h>
 
 #import "HeadphoneKeyEventDelegate.h"
 #import "dome_key_map.h"
 
-@interface HeadphoneKeyEventBluetooth : NSObject {
+@interface HeadphoneKeyEventBluetooth : NSObject <IOBluetoothDevicePairDelegate> {
     id <HeadphoneKeyEventDelegate> _delegate;
 }
 
diff --git a/DomeKey/HeadphoneKeyEventBluetooth.m b/DomeKey/HeadphoneKeyEventBluetooth.m
index 52e22db..839a4ba 100644
--- a/DomeKey/HeadphoneKeyEventBluetooth.m
+++ b/DomeKey/HeadphoneKeyEventBluetooth.m
@@ -16,20 +16,27 @@
     if (self) {
         _delegate = delegate;
 
-        MPRemoteCommandCenter *cc = [MPRemoteCommandCenter sharedCommandCenter];
-        [cc playCommand];
-        [cc pauseCommand];
-        [cc stopCommand];
-        [cc togglePlayPauseCommand];
-        // [cc nextTrackCommand];
-        // [cc seekForwardCommand];
-        // [cc previousTrackCommand];
-        // [cc seekBackwardCommand];
+        IOBluetoothUserNotification *notification = [IOBluetoothDevice
+            registerForConnectNotifications:self
+            selector:@selector(connectNotification:forDevice:)];
+        if (!notification) {
+            // TODO: error
+            NSLog(@"Connection notification error");
+        }
     }
     return self;
 }
 
-MPRemoteCommandHandler key_pressed(HeadphoneButton button) {
+- (void)devicePairingFinished:(id)sender
+    error:(IOReturn)error
+{
+    NSLog(@"Paired: %@", sender);
+}
+
+- (void)connectNotification:(IOBluetoothUserNotification *)notification
+    forDevice:(IOBluetoothDevice *)device
+{
+    NSLog(@"Paired notification: %@ ; Device: %@", notification, device);
 }
 
 @end