Vibration support on legacy devices

iOS/GBHapticManager.m

@@ -1,4 +1,5 @@
 #import "GBHapticManager.h"
+#import "GBHapticManagerLegacy.h"
 #import <CoreHaptics/CoreHaptics.h>
 
 @implementation GBHapticManager
@@ -25,15 +26,14 @@
 {
     self = [super init];
     if (!self) return nil;
+    if (self.class != [GBHapticManager class]) return self;
+    
     if (@available(iOS 13.0, *)) {
-        _engine = [[CHHapticEngine alloc] initAndReturnError:nil];
-        _engine.playsHapticsOnly = true;
-        _engine.autoShutdownEnabled = true;
+            _engine = [[CHHapticEngine alloc] initAndReturnError:nil];
+            _engine.playsHapticsOnly = true;
+            _engine.autoShutdownEnabled = true;
     }
-    else {
-        return nil;
-    }
-    if (!_engine) return nil;
+    if (!_engine) return [[GBHapticManagerLegacy alloc] init];
     return self;
 }
 

iOS/GBHapticManagerLegacy.h

@@ -0,0 +1,5 @@
+#import "GBHapticManager.h"
+
+@interface GBHapticManagerLegacy : GBHapticManager
+
+@end

iOS/GBHapticManagerLegacy.m

@@ -0,0 +1,27 @@
+#import "GBHapticManagerLegacy.h"
+#import <UIKit/UIKit.h>
+#import <AudioToolbox/AudioToolbox.h>
+
+@implementation GBHapticManagerLegacy
+
+- (void)doTapHaptic
+{
+    [[[UIImpactFeedbackGenerator alloc] initWithStyle:UIImpactFeedbackStyleMedium] impactOccurred];
+}
+
+- (void)setRumbleStrength:(double)rumble
+{
+    void AudioServicesStopSystemSound(SystemSoundID inSystemSoundID);
+    void AudioServicesPlaySystemSoundWithVibration(SystemSoundID inSystemSoundID, id arg, NSDictionary* vibratePattern);
+    if (rumble) {
+        AudioServicesPlaySystemSoundWithVibration(kSystemSoundID_Vibrate, nil, @{@"Intensity": @(rumble),
+                                                                                 @"OffDuration": @0,
+                                                                                 @"OnDuration": @100,
+                                                                                 @"VibePattern": @[@YES, @1000],
+        });
+    }
+    else {
+        AudioServicesStopSystemSound(kSystemSoundID_Vibrate);
+    }
+}
+@end