From a6878c85a8152932560a6d35dff686f943d0323f Mon Sep 17 00:00:00 2001
From: larssand <larssand@LPW0JW6L1>
Date: Thu, 19 Mar 2026 20:51:29 +0100
Subject: [PATCH] Clamp stale next-lap prediction

---
 src/app.js | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/app.js b/src/app.js
index 796daa7..9b0d7d7 100644
--- a/src/app.js
+++ b/src/app.js
@@ -7088,6 +7088,7 @@ function buildLeaderboard(session) {
   const isFreePractice = sessionType === "free_practice";
   const isOpenPractice = sessionType === "open_practice";
   const isRollingPractice = isFreePractice || isOpenPractice;
+  const { maxLapMs } = getSessionLapWindow(session);
   const nowTs = Date.now();
   const rows = Object.values(result.competitors).map((row) => {
     const allPassings = getCompetitorPassings(session, row, { includeInvalid: true });
@@ -7115,10 +7116,18 @@ function buildLeaderboard(session) {
         ? bestLapMs
         : null;
     const currentLapElapsedMs = lastPassingTs ? Math.max(0, nowTs - lastPassingTs) : 0;
-    const predictedRemainingMs = predictionBaseMs ? predictionBaseMs - currentLapElapsedMs : null;
-    const predictedProgress = predictionBaseMs ? currentLapElapsedMs / predictionBaseMs : 0;
+    const predictionStaleMs = predictionBaseMs
+      ? Math.max(
+          predictionBaseMs * 2,
+          Number.isFinite(maxLapMs) && maxLapMs > 0 ? maxLapMs : 0,
+          15000
+        )
+      : 0;
+    const predictionActive = Boolean(predictionBaseMs && lastPassingTs && currentLapElapsedMs <= predictionStaleMs);
+    const predictedRemainingMs = predictionActive ? predictionBaseMs - currentLapElapsedMs : null;
+    const predictedProgress = predictionActive ? currentLapElapsedMs / predictionBaseMs : 0;
     const predictionTone =
-      !predictionBaseMs || predictedProgress <= 0.85
+      !predictionActive || predictedProgress <= 0.85
         ? "good"
         : predictedProgress <= 1
         ? "warn"