From 01f36ea41011fdd6ec77e4b1a799193bef58aa91 Mon Sep 17 00:00:00 2001
From: Alexander <74536256+alexander-at-t@users.noreply.github.com>
Date: Wed, 29 Jan 2025 02:00:30 +0200
Subject: [PATCH] Fix negative offset of reconnect delay (#8718) (#8719)

RTDB Fix negative offset of reconnect delay. Fixes #8718.
---
 .changeset/chilled-clocks-remember.md              | 6 ++++++
 packages/database/src/core/PersistentConnection.ts | 6 ++++--
 2 files changed, 10 insertions(+), 2 deletions(-)
 create mode 100644 .changeset/chilled-clocks-remember.md

diff --git a/.changeset/chilled-clocks-remember.md b/.changeset/chilled-clocks-remember.md
new file mode 100644
index 00000000000..cbc0ec71a1f
--- /dev/null
+++ b/.changeset/chilled-clocks-remember.md
@@ -0,0 +1,6 @@
+---
+"@firebase/database": patch
+'firebase': patch
+---
+
+Fix a potential for a negative offset when calculating last reconnect times. This could cause lengthy reconnect delays in some scenarios. Fixes #8718.
diff --git a/packages/database/src/core/PersistentConnection.ts b/packages/database/src/core/PersistentConnection.ts
index 4e12b37088b..4070c4fea98 100644
--- a/packages/database/src/core/PersistentConnection.ts
+++ b/packages/database/src/core/PersistentConnection.ts
@@ -797,8 +797,10 @@ export class PersistentConnection extends ServerActions {
         this.lastConnectionEstablishedTime_ = null;
       }
 
-      const timeSinceLastConnectAttempt =
-        new Date().getTime() - this.lastConnectionAttemptTime_;
+      const timeSinceLastConnectAttempt = Math.max(
+        0,
+        new Date().getTime() - this.lastConnectionAttemptTime_
+      );
       let reconnectDelay = Math.max(
         0,
         this.reconnectDelay_ - timeSinceLastConnectAttempt