fix: data race causing multiple initial events and crash with low net… (#40)

* fix: data race causing multiple initial events and crash with low network throughput

* invoke oncomplete

Author: atierian

Sources/FaceLiveness/AV/VideoChunker.swift

@@ -33,6 +33,7 @@ final class VideoChunker {
     }
 
     func start() {
+        guard state == .pending else { return }
         state = .writing
         assetWriter.startWriting()
         assetWriter.startSession(atSourceTime: .zero)

Sources/FaceLiveness/Views/Liveness/FaceLivenessDetectionViewModel+FaceDetectionResultHandler.swift

@@ -54,11 +54,12 @@ extension FaceLivenessDetectionViewModel: FaceDetectionResultHandler {
                     }
                 }
             case .recording(ovalDisplayed: false):
-                drawOval()
-                sendInitialFaceDetectedEvent(
-                    initialFace: normalizedFace.boundingBox,
-                    videoStartTime: Date().timestampMilliseconds
-                )
+                drawOval(onComplete: {
+                    self.sendInitialFaceDetectedEvent(
+                        initialFace: normalizedFace.boundingBox,
+                        videoStartTime: Date().timestampMilliseconds
+                    )
+                })
             case .recording(ovalDisplayed: true):
                 guard let sessionConfiguration = sessionConfiguration else { return }
                 let instruction = faceInOvalMatching.faceMatchState(

Sources/FaceLiveness/Views/Liveness/FaceLivenessDetectionViewModel.swift

@@ -134,8 +134,7 @@ class FaceLivenessDetectionViewModel: ObservableObject {
         }
     }
 
-
-    func drawOval() {
+    func drawOval(onComplete: @escaping () -> Void) {
         guard livenessState.state == .recording(ovalDisplayed: false),
               let ovalParameters = sessionConfiguration?.ovalMatchChallenge.oval
         else { return }
@@ -158,6 +157,7 @@ class FaceLivenessDetectionViewModel: ObservableObject {
         livenessViewControllerDelegate?.drawOvalInCanvas(normalizedOvalRect)
         DispatchQueue.main.async {
             self.livenessState.ovalDisplayed()
+            onComplete()
         }
         ovalRect = normalizedOvalRect
     }
@@ -212,6 +212,7 @@ class FaceLivenessDetectionViewModel: ObservableObject {
         initialFace: CGRect,
         videoStartTime: UInt64
     ) {
+        guard initialClientEvent == nil else { return }
         videoChunker.start()
 
         let initialFace = FaceDetection(