From a48ac8fa791c95462355e2c2d9511f859535a9f7 Mon Sep 17 00:00:00 2001
From: Denys Smirnov <dennwc@pm.me>
Date: Mon, 6 Oct 2025 20:24:50 +0300
Subject: [PATCH] Fix zero time handling in mono package.

---
 .changeset/mono-fix-zero.md |  5 +++++
 utils/mono/mono.go          |  3 +++
 utils/mono/mono_test.go     | 17 +++++++++++++++++
 3 files changed, 25 insertions(+)
 create mode 100644 .changeset/mono-fix-zero.md
 create mode 100644 utils/mono/mono_test.go

diff --git a/.changeset/mono-fix-zero.md b/.changeset/mono-fix-zero.md
new file mode 100644
index 000000000..04b637d07
--- /dev/null
+++ b/.changeset/mono-fix-zero.md
@@ -0,0 +1,5 @@
+---
+"@livekit/protocol": patch
+---
+
+Fix zero time handling in mono package.
diff --git a/utils/mono/mono.go b/utils/mono/mono.go
index 624daaa82..eab94df71 100644
--- a/utils/mono/mono.go
+++ b/utils/mono/mono.go
@@ -22,6 +22,9 @@ var (
 )
 
 func FromTime(t time.Time) time.Time {
+	if t.IsZero() {
+		return time.Time{}
+	}
 	return epoch.Add(t.Sub(epoch))
 }
 
diff --git a/utils/mono/mono_test.go b/utils/mono/mono_test.go
new file mode 100644
index 000000000..a3a3c4b6e
--- /dev/null
+++ b/utils/mono/mono_test.go
@@ -0,0 +1,17 @@
+package mono
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestMonoZero(t *testing.T) {
+	ts := time.Time{}
+	ts2 := FromTime(ts)
+	require.True(t, ts.IsZero())
+	require.True(t, ts2.IsZero())
+	require.True(t, ts.Equal(ts2))
+	require.Equal(t, ts.String(), ts2.String())
+}