From 1b01e8f65f924d9c53c29e496644439408f70740 Mon Sep 17 00:00:00 2001
From: Matthew Chen <matthew@signal.org>
Date: Fri, 27 Jul 2018 12:58:05 -0400
Subject: [PATCH] Clean up timer animation.

---
 .../ConversationView/Cells/OWSMessageTimerView.m              | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Signal/src/ViewControllers/ConversationView/Cells/OWSMessageTimerView.m b/Signal/src/ViewControllers/ConversationView/Cells/OWSMessageTimerView.m
index 5a8fc48fc..5cc6eabd8 100644
--- a/Signal/src/ViewControllers/ConversationView/Cells/OWSMessageTimerView.m
+++ b/Signal/src/ViewControllers/ConversationView/Cells/OWSMessageTimerView.m
@@ -82,7 +82,9 @@ const CGFloat kDisappearingMessageIconSize = 12.f;
         return;
     }
 
-    CGFloat secondsLeft = MAX(0, (self.expirationTimestamp - [NSDate ows_millisecondTimeStamp]) / 1000.f);
+    uint64_t nowTimestamp = [NSDate ows_millisecondTimeStamp];
+    CGFloat secondsLeft
+        = (self.expirationTimestamp > nowTimestamp ? (self.expirationTimestamp - nowTimestamp) / 1000.f : 0.f);
     CGFloat progress = 0.f;
     if (self.initialDurationSeconds > 0) {
         progress = CGFloatClamp(secondsLeft / self.initialDurationSeconds, 0.f, 1.f);