In progress capability observations

2 files changed, 135 insertions, 9 deletions

diff --git a/SmartDeviceLink/SDLSystemCapabilityManager.h b/SmartDeviceLink/SDLSystemCapabilityManager.h
index 11e31a1c2..da6d21ee4 100644
--- a/SmartDeviceLink/SDLSystemCapabilityManager.h
+++ b/SmartDeviceLink/SDLSystemCapabilityManager.h
@@ -24,6 +24,7 @@
 @class SDLPresetBankCapabilities;
 @class SDLRemoteControlCapabilities;
 @class SDLSoftButtonCapabilities;
+@class SDLSystemCapability;
 @class SDLSystemCapabilityManager;
 @class SDLVideoStreamingCapability;
 
@@ -31,7 +32,6 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-
 /**
  *  A completion handler called after a request for the capability type is returned from the remote system.
  *
@@ -40,6 +40,13 @@ NS_ASSUME_NONNULL_BEGIN
  */
 typedef void (^SDLUpdateCapabilityHandler)(NSError * _Nullable error, SDLSystemCapabilityManager *systemCapabilityManager);
 
+/**
+ An observer block whenever a subscription is called.
+
+ @param systemCapabilityManager This manager. The user of the handler can then use the manager to pull the newest data.
+ */
+typedef void (^SDLCapabilityUpdateHandler)(SDLSystemCapabilityManager *systemCapabilityManager);
+
 
 @interface SDLSystemCapabilityManager : NSObject
 
@@ -198,6 +205,37 @@ typedef void (^SDLUpdateCapabilityHandler)(NSError * _Nullable error, SDLSystemC
  */
 - (void)updateCapabilityType:(SDLSystemCapabilityType)type completionHandler:(SDLUpdateCapabilityHandler)handler;
 
+/**
+ Subscribe to a particular capability type using a block callback
+
+ @param type The type of capability to subscribe to
+ @param block The block to be called when the capability is updated
+ @return An object that can be used to unsubscribe the block using unsubscribeFromCapabilityType:withObserver: by passing it in the observer callback
+ */
+- (id<NSObject>)subscribeToCapabilityType:(SDLSystemCapabilityType)type usingBlock:(SDLCapabilityUpdateHandler)block;
+
+/**
+ * Subscribe to a particular capability type with a selector callback. The selector supports the following parameters:
+ *
+ * 1. No parameters e.g. `- (void)phoneCapabilityUpdated;`
+ * 2. One `SDLSystemCapability *` parameter e.g. `- (void)phoneCapabilityUpdated:(SDLSystemCapability *)capability`
+ *
+ * This method will be called immediately with the current value and called every time the value is updated on RPC v5.1.0+ systems (`supportsSubscriptions == YES`). If this method is called on a sub-v5.1.0 system (`supportsSubscriptions == NO`), the method will return `NO` and the selector will never be called.
+ *
+ * @param type The type of the system capability to subscribe to
+ * @param observer The object that will have `selector` called whenever the capability is updated
+ * @param selector The selector on `observer` that will be called whenever the capability is updated
+ * @return Whether or not the subscription succeeded. `NO` if the connected system doesn't support capability subscriptions, or if the `selector` doesn't support the correct parameters (see above)
+ */
+- (BOOL)subscribeToCapabilityType:(SDLSystemCapabilityType)type withObserver:(id)observer selector:(SEL)selector;
+
+/**
+ * Unsubscribe from a particular capability type. If it was subscribed with a block, the return value should be passed to the `observer` to unsubscribe the block. If it was subscribed with a selector, the `observer` object should be passed to unsubscribe the object selector.
+ *
+ * @param type The type of the system capability to unsubscribe from
+ * @param observer The object that will be unsubscribed. If a block was subscribed, the return value should be passed. If a selector was subscribed, the observer object should be passed.
+ */
+- (void)unsubscribeFromCapabilityType:(SDLSystemCapabilityType)type withObserver:(id)observer;
 
 @end
 
diff --git a/SmartDeviceLink/SDLSystemCapabilityManager.m b/SmartDeviceLink/SDLSystemCapabilityManager.m
index bbe839bcf..49344e751 100644
--- a/SmartDeviceLink/SDLSystemCapabilityManager.m
+++ b/SmartDeviceLink/SDLSystemCapabilityManager.m
@@ -34,6 +34,43 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
+@interface SDLSystemCapabilityObserver : NSObject
+
+@property (strong, nonatomic) id<NSObject> observer;
+@property (assign, nonatomic) SEL selector;
+@property (copy, nonatomic) SDLCapabilityUpdateHandler block;
+
+- (instancetype)initWithObserver:(id<NSObject>)observer selector:(SEL)selector;
+- (instancetype)initWithObserver:(id<NSObject>)observer block:(SDLCapabilityUpdateHandler)block;
+
+@end
+
+@implementation SDLSystemCapabilityObserver
+
+- (instancetype)initWithObserver:(id<NSObject>)observer selector:(SEL)selector {
+    self = [super init];
+    if (!self) { return nil; }
+
+    _observer = observer;
+    _selector = selector;
+
+    return self;
+}
+
+- (instancetype)initWithObserver:(id<NSObject>)observer block:(SDLCapabilityUpdateHandler)block {
+    self = [super init];
+    if (!self) { return nil; }
+
+    _observer = observer;
+    _block = block;
+
+    return self;
+}
+
+@end
+
+
+
 @interface SDLSystemCapabilityManager ()
 
 typedef NSString * SDLServiceID;
@@ -58,6 +95,8 @@ typedef NSString * SDLServiceID;
 
 @property (nullable, strong, nonatomic) NSMutableDictionary<SDLServiceID, SDLAppServiceCapability *> *appServicesCapabilitiesDictionary;
 
+@property (strong, nonatomic) NSMutableDictionary<SDLSystemCapabilityType, NSMutableArray<SDLSystemCapabilityObserver *> *> *capabilityObservers;
+
 @property (nullable, strong, nonatomic) SDLSystemCapability *lastReceivedCapability;
 
 @property (assign, nonatomic) BOOL isFirstHMILevelFull;
@@ -78,6 +117,11 @@ typedef NSString * SDLServiceID;
     _isFirstHMILevelFull = NO;
     _appServicesCapabilitiesDictionary = [NSMutableDictionary dictionary];
 
+    _capabilityObservers = [NSMutableDictionary dictionary];
+    for (SDLSystemCapabilityType capabilityType in [self.class sdl_systemCapabilityTypes]) {
+        _capabilityObservers[capabilityType] = @[];
+    }
+
     [self sdl_registerForNotifications];    
 
     return self;
@@ -270,26 +314,26 @@ typedef NSString * SDLServiceID;
  */
 - (BOOL)sdl_saveSystemCapability:(SDLSystemCapability *)systemCapability completionHandler:(nullable SDLUpdateCapabilityHandler)handler {
     if ([self.lastReceivedCapability isEqual:systemCapability]) {
-        return [self sdl_callSaveHandlerAndReturnWithValue:NO handler:handler];
+        return [self sdl_callSaveHandlerForCapabilityType:systemCapability.systemCapabilityType andReturnWithValue:NO handler:handler];
     }
     self.lastReceivedCapability = systemCapability;
 
     SDLSystemCapabilityType systemCapabilityType = systemCapability.systemCapabilityType;
 
     if ([systemCapabilityType isEqualToEnum:SDLSystemCapabilityTypePhoneCall]) {
-        if ([self.phoneCapability isEqual:systemCapability.phoneCapability]) { return [self sdl_callSaveHandlerAndReturnWithValue:NO handler:handler]; }
+        if ([self.phoneCapability isEqual:systemCapability.phoneCapability]) { return [self sdl_callSaveHandlerForCapabilityType:systemCapabilityType andReturnWithValue:NO handler:handler]; }
         self.phoneCapability = systemCapability.phoneCapability;
     } else if ([systemCapabilityType isEqualToEnum:SDLSystemCapabilityTypeNavigation]) {
-        if ([self.navigationCapability isEqual:systemCapability.navigationCapability]) { return [self sdl_callSaveHandlerAndReturnWithValue:NO handler:handler]; }
+        if ([self.navigationCapability isEqual:systemCapability.navigationCapability]) { return [self sdl_callSaveHandlerForCapabilityType:systemCapabilityType andReturnWithValue:NO handler:handler]; }
         self.navigationCapability = systemCapability.navigationCapability;
     } else if ([systemCapabilityType isEqualToEnum:SDLSystemCapabilityTypeRemoteControl]) {
-        if ([self.remoteControlCapability isEqual:systemCapability.remoteControlCapability]) { return [self sdl_callSaveHandlerAndReturnWithValue:NO handler:handler]; }
+        if ([self.remoteControlCapability isEqual:systemCapability.remoteControlCapability]) { return [self sdl_callSaveHandlerForCapabilityType:systemCapabilityType andReturnWithValue:NO handler:handler]; }
         self.remoteControlCapability = systemCapability.remoteControlCapability;
     } else if ([systemCapabilityType isEqualToEnum:SDLSystemCapabilityTypeVideoStreaming]) {
-        if ([self.videoStreamingCapability isEqual:systemCapability.videoStreamingCapability]) { return [self sdl_callSaveHandlerAndReturnWithValue:NO handler:handler]; }
+        if ([self.videoStreamingCapability isEqual:systemCapability.videoStreamingCapability]) { return [self sdl_callSaveHandlerForCapabilityType:systemCapabilityType andReturnWithValue:NO handler:handler]; }
         self.videoStreamingCapability = systemCapability.videoStreamingCapability;
     } else if ([systemCapabilityType isEqualToEnum:SDLSystemCapabilityTypeAppServices]) {
-        if ([self.appServicesCapabilities isEqual:systemCapability.appServicesCapabilities]) { return [self sdl_callSaveHandlerAndReturnWithValue:NO handler:handler]; }
+        if ([self.appServicesCapabilities isEqual:systemCapability.appServicesCapabilities]) { return [self sdl_callSaveHandlerForCapabilityType:systemCapabilityType andReturnWithValue:NO handler:handler]; }
         [self sdl_saveAppServicesCapabilitiesUpdate:systemCapability.appServicesCapabilities];
     } else {
         SDLLogW(@"Received response for unknown System Capability Type: %@", systemCapabilityType);
@@ -298,15 +342,34 @@ typedef NSString * SDLServiceID;
 
     SDLLogD(@"Updated system capability manager with new data: %@", systemCapability);
 
-    return [self sdl_callSaveHandlerAndReturnWithValue:YES handler:handler];
+    return [self sdl_callSaveHandlerForCapabilityType:systemCapabilityType andReturnWithValue:YES handler:handler];
 }
 
-- (BOOL)sdl_callSaveHandlerAndReturnWithValue:(BOOL)value handler:(nullable SDLUpdateCapabilityHandler)handler {
+- (BOOL)sdl_callSaveHandlerForCapabilityType:(SDLSystemCapabilityType)type andReturnWithValue:(BOOL)value handler:(nullable SDLUpdateCapabilityHandler)handler {
     if (handler == nil) { return value; }
     handler(nil, self);
+
+    for (SDLSystemCapabilityObserver *observer in self.capabilityObservers[type]) {
+        if (observer.block != nil) {
+            observer.block(self);
+        } else {
+            if ([observer.observer respondsToSelector:observer.selector]) {
+                [observer.observer performSelector:observer.selector];
+            }
+        }
+    }
+
     return value;
 }
 
+//- (SDLSystemCapability *)capabilityForType:(SDLSystemCapabilityType)type {
+//    if ([type isEqualToEnum:SDLSystemCapabilityTypePhoneCall]) {
+//        return [[SDLSystemCapability alloc] initWithPhoneCapability:self.phoneCapability];
+//    } else if ([type isEqualToEnum:SDLSystemCapabilityTypeNavigation]) {
+//        return [SDLSystemcap] self.navigationCapability;
+//    }
+//}
+
 - (void)sdl_saveAppServicesCapabilitiesUpdate:(SDLAppServicesCapabilities *)newCapabilities {
     for (SDLAppServiceCapability *capability in newCapabilities.appServices) {
         if (capability.updateReason == nil) {
@@ -321,6 +384,31 @@ typedef NSString * SDLServiceID;
     }
 }
 
+#pragma mark - Subscriptions
+
+- (id<NSObject>)subscribeToCapabilityType:(SDLSystemCapabilityType)type usingBlock:(SDLCapabilityUpdateHandler)block {
+    SDLSystemCapabilityObserver *observerObject = [[SDLSystemCapabilityObserver alloc] initWithObserver:[[NSObject alloc] init] block:block];
+    [self.capabilityObservers[type] addObject:observerObject];
+
+    return observerObject.observer;
+}
+
+- (BOOL)subscribeToCapabilityType:(SDLSystemCapabilityType)type withObserver:(id<NSObject>)observer selector:(SEL)selector {
+    SDLSystemCapabilityObserver *observerObject = [[SDLSystemCapabilityObserver alloc] initWithObserver:observer selector:selector];
+    [self.capabilityObservers[type] addObject:observerObject];
+
+    return observerObject.observer;
+}
+
+- (void)unsubscribeFromCapabilityType:(SDLSystemCapabilityType)type withObserver:(id)observer {
+    for (SDLSystemCapabilityObserver *capabilityObserver in self.capabilityObservers[type]) {
+        if ([observer isEqual:capabilityObserver.observer]) {
+            [self.capabilityObservers[type] removeObject:capabilityObserver];
+            break;
+        }
+    }
+}
+
 @end
 
 NS_ASSUME_NONNULL_END