From abe085ce5c489352fa178796ad9a2feee26e619b Mon Sep 17 00:00:00 2001
From: Ian Saultz <52051793+atierian@users.noreply.github.com>
Date: Thu, 13 Jul 2023 11:42:27 -0400
Subject: [PATCH] =?UTF-8?q?fix:=20data=20race=20causing=20multiple=20initi?=
 =?UTF-8?q?al=20events=20and=20crash=20with=20low=20net=E2=80=A6=20(#40)?=
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* fix: data race causing multiple initial events and crash with low network throughput

* invoke oncomplete
---
 Sources/FaceLiveness/AV/VideoChunker.swift            |  1 +
 ...etectionViewModel+FaceDetectionResultHandler.swift | 11 ++++++-----
 .../Liveness/FaceLivenessDetectionViewModel.swift     |  5 +++--
 3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/Sources/FaceLiveness/AV/VideoChunker.swift b/Sources/FaceLiveness/AV/VideoChunker.swift
index 31b8adc0..326e2bc1 100644
--- a/Sources/FaceLiveness/AV/VideoChunker.swift
+++ b/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)
diff --git a/Sources/FaceLiveness/Views/Liveness/FaceLivenessDetectionViewModel+FaceDetectionResultHandler.swift b/Sources/FaceLiveness/Views/Liveness/FaceLivenessDetectionViewModel+FaceDetectionResultHandler.swift
index 04b193de..8b8876a1 100644
--- a/Sources/FaceLiveness/Views/Liveness/FaceLivenessDetectionViewModel+FaceDetectionResultHandler.swift
+++ b/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(
diff --git a/Sources/FaceLiveness/Views/Liveness/FaceLivenessDetectionViewModel.swift b/Sources/FaceLiveness/Views/Liveness/FaceLivenessDetectionViewModel.swift
index e21d261c..5b8380fa 100644
--- a/Sources/FaceLiveness/Views/Liveness/FaceLivenessDetectionViewModel.swift
+++ b/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(