Extract headphone key listener to `HeadphoneKeyEventWired`

Move the DDHidLib headphone button event listener from `HeadphoneKey` to
`HeadphoneKeyEventWired`. This creates a common interface for both wired
and wireless Bluetooth headphones.

The DDHidLib listener now lives in its own class dedicated to wired
headphones. A new `HeadphoneKeyEventBluetooth` will set up the event
listener for Bluetooth headphones.

Both `HeadphoneKeyEvent_` listeners call a delegate method set up on
`HeadphoneKey` that relays the pressed headphone button.

5 files changed, 69 insertions, 35 deletions

diff --git a/DomeKey/HeadphoneKey.h b/DomeKey/HeadphoneKey.h
index 472f100..6670ff5 100644
--- a/DomeKey/HeadphoneKey.h
+++ b/DomeKey/HeadphoneKey.h
@@ -48,22 +48,18 @@
 //
 
 #import <Foundation/Foundation.h>
-#import "DDHidAppleMikey.h"
 
+#import "HeadphoneKeyEventDelegate.h"
+#import "HeadphoneKeyEventWired.h"
 #import "Mappings.h"
 #import "Sounds.h"
 #import "dome_key_map.h"
 #import "log.h"
 
-typedef enum KeyPress : BOOL {
-    KeyPressDown = YES,
-    KeyPressUp = NO
-} KeyPress;
-
 static const Milliseconds TIMEOUT_DEFAULT = 500;
 
-@interface HeadphoneKey : NSObject {
-    NSArray *_mikeys;
+@interface HeadphoneKey : NSObject <HeadphoneKeyEventDelegate> {
+    HeadphoneKeyEventWired *_wired_headphone_event;
     NSMutableArray *_key_buffer;
     Mappings *_mappings;
     Milliseconds _timeout;
diff --git a/DomeKey/HeadphoneKey.m b/DomeKey/HeadphoneKey.m
index e5665d1..3aa79ce 100644
--- a/DomeKey/HeadphoneKey.m
+++ b/DomeKey/HeadphoneKey.m
@@ -58,6 +58,9 @@ static BOOL _play_audio;
 {
     self = [super init];
     if (self) {
+        _wired_headphone_event = [[HeadphoneKeyEventWired alloc]
+            initWithDelegate:self];
+
         _key_buffer = [[NSMutableArray alloc] initWithCapacity:5];
 
         _mappings = [[Mappings alloc] init];
@@ -69,13 +72,6 @@ static BOOL _play_audio;
         _timeout = TIMEOUT_DEFAULT;
 
         _play_audio = NO;
-
-        _mikeys = [DDHidAppleMikey allMikeys];
-        [_mikeys makeObjectsPerformSelector:@selector(setDelegate:)
-            withObject:self];
-        [_mikeys makeObjectsPerformSelector:@selector(setListenInExclusiveMode:)
-            withObject:(id)kCFBooleanTrue];
-        [_mikeys makeObjectsPerformSelector:@selector(startListening)];
     }
     return self;
 }
@@ -94,26 +90,9 @@ static BOOL _play_audio;
     return self;
 }
 
-- (void)ddhidAppleMikey:(DDHidAppleMikey *)mikey
-                  press:(unsigned)usageId
-               upOrDown:(BOOL)upOrDown
+- (void)headphoneButtonWasPressed:(HeadphoneButton)button
 {
-    if (upOrDown == KeyPressUp) {
-        switch (usageId) {
-        case kHIDUsage_Csmr_PlayOrPause:
-            LogDebug(@"Middle");
-            [self handleDeadKey:HeadphoneButton_Play];
-            break;
-        case kHIDUsage_Csmr_VolumeIncrement:
-            LogDebug(@"Top");
-            [self handleDeadKey:HeadphoneButton_Up];
-            break;
-        case kHIDUsage_Csmr_VolumeDecrement:
-            LogDebug(@"Bottom");
-            [self handleDeadKey:HeadphoneButton_Down];
-            break;
-        }
-    }
+    [self handleDeadKey:button];
 }
 
 - (void)handleDeadKey:(HeadphoneButton)button
diff --git a/DomeKey/HeadphoneKeyEventDelegate.h b/DomeKey/HeadphoneKeyEventDelegate.h
index 8fd8eba..444919a 100644
--- a/DomeKey/HeadphoneKeyEventDelegate.h
+++ b/DomeKey/HeadphoneKeyEventDelegate.h
@@ -9,5 +9,12 @@
 #ifndef HeadphoneKeyEventDelegate_h
 #define HeadphoneKeyEventDelegate_h
 
+#include "dome_key_map.h"
+
+@protocol HeadphoneKeyEventDelegate
+
+- (void)headphoneButtonWasPressed:(HeadphoneButton)button;
+
+@end
 
 #endif /* HeadphoneKeyEventDelegate_h */
diff --git a/DomeKey/HeadphoneKeyEventWired.h b/DomeKey/HeadphoneKeyEventWired.h
index f3dd630..b24bb56 100644
--- a/DomeKey/HeadphoneKeyEventWired.h
+++ b/DomeKey/HeadphoneKeyEventWired.h
@@ -7,7 +7,21 @@
 //
 
 #import <Foundation/Foundation.h>
+#import "DDHidAppleMikey.h"
 
-@interface HeadphoneKeyEventWired : NSObject
+#import "HeadphoneKeyEventDelegate.h"
+#import "log.h"
+
+typedef enum KeyPress : BOOL {
+    KeyPressDown = YES,
+    KeyPressUp = NO
+} KeyPress;
+
+@interface HeadphoneKeyEventWired : NSObject {
+    NSArray *_mikeys;
+    id <HeadphoneKeyEventDelegate> _delegate;
+}
+
+- (instancetype)initWithDelegate:(id <HeadphoneKeyEventDelegate>)delegate;
 
 @end
diff --git a/DomeKey/HeadphoneKeyEventWired.m b/DomeKey/HeadphoneKeyEventWired.m
index 7245146..8364d2a 100644
--- a/DomeKey/HeadphoneKeyEventWired.m
+++ b/DomeKey/HeadphoneKeyEventWired.m
@@ -10,4 +10,42 @@
 
 @implementation HeadphoneKeyEventWired
 
+- (instancetype)initWithDelegate:(id <HeadphoneKeyEventDelegate>)delegate
+{
+    self = [self init];
+    if (self) {
+        _delegate = delegate;
+
+        _mikeys = [DDHidAppleMikey allMikeys];
+        [_mikeys makeObjectsPerformSelector:@selector(setDelegate:)
+            withObject:self];
+        [_mikeys makeObjectsPerformSelector:@selector(setListenInExclusiveMode:)
+            withObject:(id)kCFBooleanTrue];
+        [_mikeys makeObjectsPerformSelector:@selector(startListening)];
+    }
+    return self;
+}
+
+- (void)ddhidAppleMikey:(DDHidAppleMikey *)mikey
+                  press:(unsigned)usageId
+               upOrDown:(BOOL)upOrDown
+{
+    if (upOrDown == KeyPressUp) {
+        switch (usageId) {
+        case kHIDUsage_Csmr_PlayOrPause:
+            LogDebug(@"Middle");
+            [_delegate headphoneButtonWasPressed:HeadphoneButton_Play];
+            break;
+        case kHIDUsage_Csmr_VolumeIncrement:
+            LogDebug(@"Top");
+            [_delegate headphoneButtonWasPressed:HeadphoneButton_Up];
+            break;
+        case kHIDUsage_Csmr_VolumeDecrement:
+            LogDebug(@"Bottom");
+            [_delegate headphoneButtonWasPressed:HeadphoneButton_Down];
+            break;
+        }
+    }
+}
+
 @end