fix: Fix torch not working on iOS (#2031)

* fix: Fix `torch` not working on iOS

* Format

* fix: Use `withSessionLock` and `withDeviceLock`

* Update CameraSession.swift

* Update RecordingSession.swift

package/ios/Core/CameraSession.swift

@@ -114,56 +114,50 @@ class CameraSession: NSObject, AVCaptureVideoDataOutputSampleBufferDelegate, AVC
       do {
         // If needed, configure the AVCaptureSession (inputs, outputs)
         if difference.isSessionConfigurationDirty {
-          // Lock Capture Session for configuration
-          ReactLogger.log(level: .info, message: "Beginning CameraSession configuration...")
-          self.captureSession.beginConfiguration()
-
-          // 1. Update input device
-          if difference.inputChanged {
-            try self.configureDevice(configuration: config)
+          try self.withSessionLock {
+            // 1. Update input device
+            if difference.inputChanged {
+              try self.configureDevice(configuration: config)
+            }
+            // 2. Update outputs
+            if difference.outputsChanged {
+              try self.configureOutputs(configuration: config)
+            }
+            // 3. Update output orientation
+            if difference.orientationChanged {
+              self.configureOrientation(configuration: config)
+            }
           }
-          // 2. Update outputs
-          if difference.outputsChanged {
-            try self.configureOutputs(configuration: config)
-          }
-          // 3. Update output orientation
-          if difference.orientationChanged {
-            self.configureOrientation(configuration: config)
-          }
-
-          // Unlock Capture Session again and submit configuration to Hardware
-          self.captureSession.commitConfiguration()
-          ReactLogger.log(level: .info, message: "Committed CameraSession configuration!")
         }
 
         // If needed, configure the AVCaptureDevice (format, zoom, low-light-boost, ..)
         if difference.isDeviceConfigurationDirty {
-          guard let device = self.videoDeviceInput?.device else {
-            throw CameraError.session(.cameraNotReady)
+          try self.withDeviceLock { device in
+            // 4. Configure format
+            if difference.formatChanged {
+              try self.configureFormat(configuration: config, device: device)
+            }
+            // 5. Configure side-props (fps, lowLightBoost)
+            if difference.sidePropsChanged {
+              try self.configureSideProps(configuration: config, device: device)
+            }
+            // 6. Configure zoom
+            if difference.zoomChanged {
+              self.configureZoom(configuration: config, device: device)
+            }
           }
-          ReactLogger.log(level: .info, message: "Beginning CaptureDevice configuration...")
-          try device.lockForConfiguration()
-
-          // 4. Configure format
-          if difference.formatChanged {
-            try self.configureFormat(configuration: config)
-          }
-          // 5. Configure side-props (fps, lowLightBoost)
-          if difference.sidePropsChanged {
-            try self.configureSideProps(configuration: config)
-          }
-          // 6. Configure zoom
-          if difference.zoomChanged {
-            try self.configureZoom(configuration: config)
-          }
-
-          device.unlockForConfiguration()
-          ReactLogger.log(level: .info, message: "Committed CaptureDevice configuration!")
         }
 
-        // 6. Start or stop the session if needed
+        // 7. Start or stop the session if needed
         self.checkIsActive(configuration: config)
 
+        // 8. Enable or disable the Torch if needed (requires session to be running)
+        if difference.torchChanged {
+          try self.withDeviceLock { device in
+            try self.configureTorch(configuration: config, device: device)
+          }
+        }
+
         // Update successful, set the new configuration!
         self.configuration = config
       } catch {
@@ -191,6 +185,41 @@ class CameraSession: NSObject, AVCaptureVideoDataOutputSampleBufferDelegate, AVC
     }
   }
 
+  /**
+   Runs the given [lambda] under an AVCaptureSession configuration lock (`beginConfiguration()`)
+   */
+  private func withSessionLock(_ lambda: () throws -> Void) throws {
+    // Lock Capture Session for configuration
+    ReactLogger.log(level: .info, message: "Beginning CameraSession configuration...")
+    captureSession.beginConfiguration()
+    defer {
+      // Unlock Capture Session again and submit configuration to Hardware
+      self.captureSession.commitConfiguration()
+      ReactLogger.log(level: .info, message: "Committed CameraSession configuration!")
+    }
+
+    // Call lambda
+    try lambda()
+  }
+
+  /**
+   Runs the given [lambda] under an AVCaptureDevice configuration lock (`lockForConfiguration()`)
+   */
+  private func withDeviceLock(_ lambda: (_ device: AVCaptureDevice) throws -> Void) throws {
+    guard let device = videoDeviceInput?.device else {
+      throw CameraError.session(.cameraNotReady)
+    }
+    ReactLogger.log(level: .info, message: "Beginning CaptureDevice configuration...")
+    try device.lockForConfiguration()
+    defer {
+      device.unlockForConfiguration()
+      ReactLogger.log(level: .info, message: "Committed CaptureDevice configuration!")
+    }
+
+    // Call lambda with Device
+    try lambda(device)
+  }
+
   /**
    Starts or stops the CaptureSession if needed (`isActive`)
    */