Remove some more unused bits in MTRDeviceController.

Controller's downloadLogFromNodeWithID is only used from MTRBaseDevice, which is
not expected to be used with a non-concrete controller.  Unfortunately, nothing
actually prevents an MTRBaseDevice beign created against a non-concrete
controller, so we can't just move this API to MTRDeviceController_Concrete.

With the implementation of downloadLogFromNodeWithID removed, _factory is unused
and can be removed.

Also, with this implementation removed the factory's downloadLogFromNodeWithID
can take MTRDeviceController_Concrete, as can the diagnostic log downloader.

Similarly, getSessionFromNode is only used from MTRBaseDevice and
MTRCallbackBridgeBase's ActionWithNodeID.  And ActionWithNodeID is only used
from DispatchAction, which is only called from MTRBaseClusters and
MTRBaseDevice, none of which is expected to work with a non-concrete
controller.  So this implementation can also be removed.

At that point directlyGetSessionForNode is only used from MTRDevice_Concrete,
so we can just move it to MTRDeviceController_Concrete.

getSessionForCommissioneeDevice is only used from ActionWithPASEDevice, which is
only used from DispatchAction, like getSessionFromNode.  So this implementation
can also be removed.

At this point asyncDispatchToMatterQueue is only used from:

* MTRBaseDevice
* MTRClusterStateCacheContainer, where it's used on a controller coming from
  MTRBaseDevice.
* MTRDevice_Concrete, where it's being used on a concrete controller.
* MTRDiagnosticLogsDownloader, where it's being used on a concrete controller.
* MTRServerAttribute/MTRServerCluster/MTRServerEndpoint, which are not usable
  with non-concrete controllers as things stand.
* MTROTAProviderDelegateBridge, where its being used on a concrete controller.

So the MTRDeviceController implementation of asyncDispatchToMatterQueue can also
be removed.

Author: bzbarsky-apple

src/darwin/Framework/CHIP/MTRDeviceController.mm

@@ -126,7 +126,6 @@ @implementation MTRDeviceController {
     MTRDeviceControllerDelegateBridge * _deviceControllerDelegateBridge;
     MTROperationalCredentialsDelegate * _operationalCredentialsDelegate;
     MTRDeviceAttestationDelegateBridge * _deviceAttestationDelegateBridge;
-    MTRDeviceControllerFactory * _factory;
     os_unfair_lock _underlyingDeviceMapLock;
     MTRCommissionableBrowser * _commissionableBrowser;
     MTRAttestationTrustStoreBridge * _attestationTrustStoreBridge;
@@ -554,65 +553,14 @@ - (BOOL)checkIsRunning:(NSError * __autoreleasing *)error
 
 - (void)getSessionForNode:(chip::NodeId)nodeID completion:(MTRInternalDeviceConnectionCallback)completion
 {
-    // Get the corresponding MTRDevice object to determine if the case/subscription pool is to be used
-    MTRDevice * device = [self deviceForNodeID:@(nodeID)];
-
-    // In the case that this device is known to use thread, queue this with subscription attempts as well, to
-    // help with throttling Thread traffic.
-    if ([device deviceUsesThread]) {
-        MTRAsyncWorkItem * workItem = [[MTRAsyncWorkItem alloc] initWithQueue:dispatch_get_global_queue(QOS_CLASS_DEFAULT, 0)];
-        [workItem setReadyHandler:^(id _Nonnull context, NSInteger retryCount, MTRAsyncWorkCompletionBlock _Nonnull workItemCompletion) {
-            MTRInternalDeviceConnectionCallback completionWrapper = ^(chip::Messaging::ExchangeManager * _Nullable exchangeManager,
-                const chip::Optional<chip::SessionHandle> & session, NSError * _Nullable error, NSNumber * _Nullable retryDelay) {
-                completion(exchangeManager, session, error, retryDelay);
-                workItemCompletion(MTRAsyncWorkComplete);
-            };
-            [self directlyGetSessionForNode:nodeID completion:completionWrapper];
-        }];
-
-        [_concurrentSubscriptionPool enqueueWorkItem:workItem descriptionWithFormat:@"device controller getSessionForNode nodeID: 0x%016llX", nodeID];
-    } else {
-        [self directlyGetSessionForNode:nodeID completion:completion];
-    }
-}
-
-- (void)directlyGetSessionForNode:(chip::NodeId)nodeID completion:(MTRInternalDeviceConnectionCallback)completion
-{
-    [self
-        asyncGetCommissionerOnMatterQueue:^(chip::Controller::DeviceCommissioner * commissioner) {
-            auto connectionBridge = new MTRDeviceConnectionBridge(completion);
-
-            // MTRDeviceConnectionBridge always delivers errors async via
-            // completion.
-            connectionBridge->connect(commissioner, nodeID);
-        }
-        errorHandler:^(NSError * error) {
-            completion(nullptr, chip::NullOptional, error, nil);
-        }];
+    MTR_ABSTRACT_METHOD();
+    completion(nullptr, chip::NullOptional, [MTRError errorForCHIPErrorCode:CHIP_ERROR_INCORRECT_STATE], nil);
 }
 
 - (void)getSessionForCommissioneeDevice:(chip::NodeId)deviceID completion:(MTRInternalDeviceConnectionCallback)completion
 {
-    [self
-        asyncGetCommissionerOnMatterQueue:^(chip::Controller::DeviceCommissioner * commissioner) {
-            chip::CommissioneeDeviceProxy * deviceProxy;
-            CHIP_ERROR err = commissioner->GetDeviceBeingCommissioned(deviceID, &deviceProxy);
-            if (err != CHIP_NO_ERROR) {
-                completion(nullptr, chip::NullOptional, [MTRError errorForCHIPErrorCode:err], nil);
-                return;
-            }
-
-            chip::Optional<chip::SessionHandle> session = deviceProxy->GetSecureSession();
-            if (!session.HasValue() || !session.Value()->AsSecureSession()->IsPASESession()) {
-                completion(nullptr, chip::NullOptional, [MTRError errorForCHIPErrorCode:CHIP_ERROR_INCORRECT_STATE], nil);
-                return;
-            }
-
-            completion(deviceProxy->GetExchangeManager(), session, nil, nil);
-        }
-        errorHandler:^(NSError * error) {
-            completion(nullptr, chip::NullOptional, error, nil);
-        }];
+    MTR_ABSTRACT_METHOD();
+    completion(nullptr, chip::NullOptional, [MTRError errorForCHIPErrorCode:CHIP_ERROR_INCORRECT_STATE], nil);
 }
 
 - (MTRTransportType)sessionTransportTypeForDevice:(MTRBaseDevice *)device
@@ -665,10 +613,8 @@ - (void)asyncGetCommissionerOnMatterQueue:(void (^)(chip::Controller::DeviceComm
 
 - (void)asyncDispatchToMatterQueue:(dispatch_block_t)block errorHandler:(nullable MTRDeviceErrorHandler)errorHandler
 {
-    auto adapter = ^(chip::Controller::DeviceCommissioner *) {
-        block();
-    };
-    [self asyncGetCommissionerOnMatterQueue:adapter errorHandler:errorHandler];
+    MTR_ABSTRACT_METHOD();
+    errorHandler([MTRError errorForCHIPErrorCode:CHIP_ERROR_INCORRECT_STATE]);
 }
 
 - (void)syncRunOnWorkQueue:(SyncWorkQueueBlock)block error:(NSError * __autoreleasing *)error
@@ -751,17 +697,10 @@ - (void)downloadLogFromNodeWithID:(NSNumber *)nodeID
                             queue:(dispatch_queue_t)queue
                        completion:(void (^)(NSURL * _Nullable url, NSError * _Nullable error))completion
 {
-    [self asyncDispatchToMatterQueue:^() {
-        [self->_factory downloadLogFromNodeWithID:nodeID
-                                       controller:self
-                                             type:type
-                                          timeout:timeout
-                                            queue:queue
-                                       completion:completion];
-    }
-        errorHandler:^(NSError * error) {
-            completion(nil, error);
-        }];
+    MTR_ABSTRACT_METHOD();
+    dispatch_async(queue, ^{
+        completion(nil, [MTRError errorForCHIPErrorCode:CHIP_ERROR_INCORRECT_STATE]);
+    });
 }
 
 - (NSArray<MTRAccessGrant *> *)accessGrantsForClusterPath:(MTRClusterPath *)clusterPath

src/darwin/Framework/CHIP/MTRDeviceControllerFactory.mm

@@ -1099,7 +1099,7 @@ - (nullable NSNumber *)neededReadPrivilegeForClusterID:(NSNumber *)clusterID att
 }
 
 - (void)downloadLogFromNodeWithID:(NSNumber *)nodeID
-                       controller:(MTRDeviceController *)controller
+                       controller:(MTRDeviceController_Concrete *)controller
                              type:(MTRDiagnosticLogType)type
                           timeout:(NSTimeInterval)timeout
                             queue:(dispatch_queue_t)queue

src/darwin/Framework/CHIP/MTRDeviceControllerFactory_Internal.h

@@ -83,7 +83,7 @@ MTR_DIRECT_MEMBERS
  * Download log of the desired type from the device.
  */
 - (void)downloadLogFromNodeWithID:(NSNumber *)nodeID
-                       controller:(MTRDeviceController *)controller
+                       controller:(MTRDeviceController_Concrete *)controller
                              type:(MTRDiagnosticLogType)type
                           timeout:(NSTimeInterval)timeout
                             queue:(dispatch_queue_t)queue

src/darwin/Framework/CHIP/MTRDeviceController_Concrete.h

@@ -19,6 +19,7 @@
 
 #import <Matter/Matter.h>
 
+#import "MTRDeviceConnectionBridge.h"
 #import "MTRDeviceControllerStartupParams_Internal.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -109,6 +110,13 @@ NS_ASSUME_NONNULL_BEGIN
  */
 - (void)clearPendingShutdown;
 
+/**
+ * Since getSessionForNode now enqueues by the subscription pool for Thread
+ * devices, MTRDevice_Concrete needs a direct non-queued access because it already
+ * makes use of the subscription pool.
+ */
+- (void)directlyGetSessionForNode:(chip::NodeId)nodeID completion:(MTRInternalDeviceConnectionCallback)completion;
+
 @end
 
 NS_ASSUME_NONNULL_END

src/darwin/Framework/CHIP/MTRDeviceController_Internal.h

@@ -243,13 +243,6 @@ NS_ASSUME_NONNULL_BEGIN
 - (MTRDevice *)_setupDeviceForNodeID:(NSNumber *)nodeID prefetchedClusterData:(nullable NSDictionary<MTRClusterPath *, MTRDeviceClusterData *> *)prefetchedClusterData;
 - (void)removeDevice:(MTRDevice *)device;
 
-/**
- * Since getSessionForNode now enqueues by the subscription pool for Thread
- * devices, MTRDevice needs a direct non-queued access because it already
- * makes use of the subscription pool.
- */
-- (void)directlyGetSessionForNode:(chip::NodeId)nodeID completion:(MTRInternalDeviceConnectionCallback)completion;
-
 @end
 
 /**

src/darwin/Framework/CHIP/MTRDevice_Concrete.mm

@@ -2388,7 +2388,7 @@ - (void)_setupSubscriptionWithReason:(NSString *)reason
     MATTER_LOG_METRIC_BEGIN(kMetricMTRDeviceInitialSubscriptionSetup);
 
     // Call directlyGetSessionForNode because the subscription setup already goes through the subscription pool queue
-    [_deviceController
+    [[self _concreteController]
         directlyGetSessionForNode:_nodeID.unsignedLongLongValue
                        completion:^(chip::Messaging::ExchangeManager * _Nullable exchangeManager,
                            const chip::Optional<chip::SessionHandle> & session, NSError * _Nullable error,
@@ -4138,6 +4138,14 @@ - (void)controllerResumed
     [self _ensureSubscriptionForExistingDelegates:@"Controller resumed"];
 }
 
+// nullable because technically _deviceController is nullable.
+- (nullable MTRDeviceController_Concrete *)_concreteController
+{
+    // We know our _deviceController is actually an MTRDeviceController_Concrete, since that's what
+    // gets passed to initWithNodeID.
+    return static_cast<MTRDeviceController_Concrete *>(_deviceController);
+}
+
 @end
 
 /* BEGIN DRAGONS: Note methods here cannot be renamed, and are used by private callers, do not rename, remove or modify behavior here */

src/darwin/Framework/CHIP/MTRDevice_Internal.h

@@ -118,7 +118,8 @@ MTR_DIRECT_MEMBERS
     NSNumber * _nodeID;
 
     // Our controller.  Declared nullable because our property is, though in
-    // practice it does not look like we ever set it to nil.
+    // practice it does not look like we ever set it to nil.  If this changes,
+    // fix _concreteController on MTRDevice_Concrete accordingly.
     MTRDeviceController * _Nullable _deviceController;
 }
 

src/darwin/Framework/CHIP/MTRDiagnosticLogsDownloader.h

@@ -20,6 +20,8 @@
 #import <Matter/MTRDeviceController.h>
 #import <Matter/MTRDiagnosticLogsType.h>
 
+#import "MTRDeviceController_Concrete.h"
+
 namespace chip {
 namespace bdx {
     class BDXTransferServerDelegate;
@@ -33,14 +35,14 @@ NS_ASSUME_NONNULL_BEGIN
 
 // Must be called on Matter queue
 - (void)downloadLogFromNodeWithID:(NSNumber *)nodeID
-                       controller:(MTRDeviceController *)controller
+                       controller:(MTRDeviceController_Concrete *)controller
                              type:(MTRDiagnosticLogType)type
                           timeout:(NSTimeInterval)timeout
                             queue:(dispatch_queue_t)queue
                        completion:(void (^)(NSURL * _Nullable url, NSError * _Nullable error))completion;
 
 // Must be called on Matter queue
-- (void)abortDownloadsForController:(MTRDeviceController *)controller;
+- (void)abortDownloadsForController:(MTRDeviceController_Concrete *)controller;
 
 @end
 

src/darwin/Framework/CHIP/MTRDiagnosticLogsDownloader.mm

@@ -86,7 +86,7 @@ - (MTRDownload * _Nullable)add:(MTRDiagnosticLogType)type
                     completion:(void (^)(NSURL * _Nullable url, NSError * _Nullable error))completion
                           done:(void (^)(MTRDownload * finishedDownload))done;
 
-- (void)abortDownloadsForController:(MTRDeviceController *)controller;
+- (void)abortDownloadsForController:(MTRDeviceController_Concrete *)controller;
 
 @end
 
@@ -354,7 +354,7 @@ - (MTRDownload * _Nullable)add:(MTRDiagnosticLogType)type
     return download;
 }
 
-- (void)abortDownloadsForController:(MTRDeviceController *)controller
+- (void)abortDownloadsForController:(MTRDeviceController_Concrete *)controller
 {
     assertChipStackLockedByCurrentThread();
 
@@ -408,7 +408,7 @@ - (void)dealloc
 }
 
 - (void)downloadLogFromNodeWithID:(NSNumber *)nodeID
-                       controller:(MTRDeviceController *)controller
+                       controller:(MTRDeviceController_Concrete *)controller
                              type:(MTRDiagnosticLogType)type
                           timeout:(NSTimeInterval)timeout
                             queue:(dispatch_queue_t)queue
@@ -462,7 +462,7 @@ - (void)downloadLogFromNodeWithID:(NSNumber *)nodeID
     }
 }
 
-- (void)abortDownloadsForController:(MTRDeviceController *)controller;
+- (void)abortDownloadsForController:(MTRDeviceController_Concrete *)controller;
 {
     assertChipStackLockedByCurrentThread();