From a237946ba04f0656c6ca14f2ef224717b2b1c740 Mon Sep 17 00:00:00 2001
From: Evan Hahn <69474926+EvanHahn-Signal@users.noreply.github.com>
Date: Thu, 10 Dec 2020 12:39:39 -0600
Subject: [PATCH] Disable camera when quickly toggling the call lobby

---
 ts/services/calling.ts | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/ts/services/calling.ts b/ts/services/calling.ts
index 63815bc0cf88..67b60c092bae 100644
--- a/ts/services/calling.ts
+++ b/ts/services/calling.ts
@@ -181,6 +181,24 @@ export class CallingClass {
 
     window.log.info('CallingClass.startCallingLobby(): Starting lobby');
 
+    // It's important that this function comes before any calls to
+    //   `videoCapturer.enableCapture` or `videoCapturer.enableCaptureAndSend` because of
+    //   a small RingRTC bug.
+    //
+    // If we tell RingRTC to start capturing video (with those methods or with
+    //   `RingRTC.setPreferredDevice`, which also captures video) multiple times in quick
+    //   succession, it will call the asynchronous `getUserMedia` twice. It'll save the
+    //   results in the same variable, which means the first call can be overridden.
+    //   Later, when we try to turn the camera off, we'll only disable the *second* result
+    //   of `getUserMedia` and the camera will stay on.
+    //
+    // We get around this by `await`ing, making sure we're all done with `getUserMedia`,
+    //   and then continuing.
+    //
+    // We should be able to move this below `this.connectGroupCall` once that RingRTC bug
+    //   is fixed. See DESKTOP-1032.
+    await this.startDeviceReselectionTimer();
+
     switch (callMode) {
       case CallMode.Direct:
         this.uxActions.showCallLobby({
@@ -221,8 +239,6 @@ export class CallingClass {
         throw missingCaseError(callMode);
     }
 
-    await this.startDeviceReselectionTimer();
-
     if (isVideoCall) {
       this.enableLocalCamera();
     }