fix(lap): keep best laps per track layout and count the current session for records

A layout switch during a running open practice kept every driver's
old-layout best lap, blocking personal-best calls and skewing the
practice leaderboard. Best laps now restart on a new layout and each
lap records its layout. The track record baseline now includes the
current session so the same record isn't called twice.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/app.js

@@ -5046,9 +5046,17 @@ function addTrackLayout(label, startedAtMs = Date.now()) {
   state.trackLayouts = normalizeTrackLayouts(layouts, { uid });
   // A practice session that keeps running across the switch moves onto the new layout;
   // its earlier laps stay on the old one because training laps are tagged per lap.
+  // Its best laps start over too: personal bests, session fastest and the leaderboard's best
+  // lap are per layout, so the old layout's times can't block or fake a new best.
   if (startedAtMs <= Date.now()) {
     state.sessions.forEach((session) => {
-      if (isPracticeSessionType(session.type) && ["running", "paused"].includes(session.status)) session.trackLayoutId = layout.id;
+      if (!isPracticeSessionType(session.type) || !["running", "paused"].includes(session.status)) return;
+      session.trackLayoutId = layout.id;
+      Object.values(state.resultsBySession?.[session.id]?.competitors || {}).forEach((entry) => {
+        entry.bestLapMs = null;
+        entry.bestLapLayoutId = layout.id;
+        delete lastOverlayBestLapByKey[`${session.id}:${entry.key}`];
+      });
     });
   }
   saveState();

src/decoder_runtime.js

@@ -337,6 +337,7 @@ export function processDecoderMessageHelper(msg, deps, decoderRole = "main") {
       laps: 0,
       lastLapMs: null,
       bestLapMs: null,
+      bestLapLayoutId: String(session.trackLayoutId || ""),
       startTimestamp: null,
       lastTimestamp: null,
     };
@@ -494,6 +495,7 @@ export function processDecoderMessageHelper(msg, deps, decoderRole = "main") {
     stintBoundary: validationWarning === "above_max_stint",
     strength: msg.strength,
     loopId: String(msg.loop_id || ""),
+    trackLayoutId: String(session.trackLayoutId || ""),
     resend: Boolean(msg.resend),
   };
 
@@ -505,6 +507,12 @@ export function processDecoderMessageHelper(msg, deps, decoderRole = "main") {
     return true;
   }
 
+  // Best laps are per track layout: an open practice that runs all season moves onto a new
+  // layout when one is added (addTrackLayout resets every best lap then), and this catches a
+  // layout change made elsewhere. Entries from before this field existed adopt the current one.
+  const layoutId = String(session.trackLayoutId || "");
+  if (entry.bestLapLayoutId === undefined) entry.bestLapLayoutId = layoutId;
+  else if (entry.bestLapLayoutId !== layoutId) { entry.bestLapMs = null; entry.bestLapLayoutId = layoutId; }
   const previousPersonalBest = Number(entry.bestLapMs || 0) || null;
   const leaderboardBefore = buildLeaderboard(session);
   const previousPosition = leaderboardBefore.findIndex((row) => row.key === key);

src/judging_logic.js

@@ -83,7 +83,12 @@ export function recalculateCompetitorFromPassings(session, rowKey, { ensureSessi
   entry.lastTimestamp = validPassings.length
     ? Number(validPassings[validPassings.length - 1].timestamp || 0) || entry.startTimestamp || session.startedAt || null
     : entry.startTimestamp || session.startedAt || null;
-  const bestLapCandidates = validPassings.map((passing) => Number(passing.lapMs || 0)).filter((lapMs) => lapMs > 500);
+  // Only laps on the session's current track layout count for the best lap (passings from
+  // before layouts were tagged have no trackLayoutId and still count).
+  const layoutId = String(session.trackLayoutId || "");
+  const bestLapCandidates = validPassings
+    .filter((passing) => passing.trackLayoutId === undefined || String(passing.trackLayoutId) === layoutId)
+    .map((passing) => Number(passing.lapMs || 0)).filter((lapMs) => lapMs > 500);
   entry.bestLapMs = bestLapCandidates.length ? Math.min(...bestLapCandidates) : null;
 }
 

src/timing_logic.js

@@ -165,9 +165,10 @@ export function ensureSessionResult(sessionId, { state }) {
 export function getTrackRecordMs(session, { state }) {
   const event = state.events.find((item) => item.id === session?.eventId);
   if (!event?.classId) return null;
+  // The current session counts too: once someone beats the old record in this session, the
+  // next driver must beat that new time - not the old record again - to be called a record.
   const candidates = state.sessions.filter((item) =>
-    item.id !== session?.id
-    && String(item.trackLayoutId || "") === String(session?.trackLayoutId || "")
+    String(item.trackLayoutId || "") === String(session?.trackLayoutId || "")
     && state.events.find((race) => race.id === item.eventId)?.classId === event.classId);
   const values = candidates
     .flatMap((item) => Object.values(state.resultsBySession[item.id]?.competitors || {}).map((row) => Number(row.bestLapMs || 0)))