Protect against invalid enums being returned (#36792)

* Adding type protection here

* Restyled by clang-format

* Safer way to do this

* Restyled by clang-format

* Fixing format

* Restyled by clang-format

* Adding error

* Restyled by clang-format

---------

Co-authored-by: Restyled.io <[email protected]>

Author: woody-apple

src/darwin/Framework/CHIP/MTRDevice_XPC.mm

@@ -322,7 +322,20 @@ - (oneway void)device:(NSNumber *)nodeID internalStateUpdated:(NSDictionary *)di
 - (MTRDeviceState)state
 {
     NSNumber * stateNumber = MTR_SAFE_CAST(self._internalState[kMTRDeviceInternalPropertyDeviceState], NSNumber);
-    return stateNumber ? static_cast<MTRDeviceState>(stateNumber.unsignedIntegerValue) : MTRDeviceStateUnknown;
+    switch (static_cast<MTRDeviceState>(stateNumber.unsignedIntegerValue)) {
+    case MTRDeviceStateUnknown:
+        return MTRDeviceStateUnknown;
+
+    case MTRDeviceStateUnreachable:
+        return MTRDeviceStateUnreachable;
+
+    case MTRDeviceStateReachable:
+        return MTRDeviceStateReachable;
+    }
+
+    MTR_LOG_ERROR("stateNumber from internal state is an invalid value: %@", stateNumber);
+
+    return MTRDeviceStateUnknown;
 }
 
 - (BOOL)deviceCachePrimed