feat: auto-select active or next trip by date

src/utils/date.js

@@ -23,3 +23,34 @@ export function findActiveTripId(trips) {
   });
   return active?.id || null;
 }
+
+export function findNextTripId(trips) {
+  const today = parseYMD(todayYMD());
+  if (!today) return null;
+
+  const next = trips
+    .map((trip) => ({ id: trip.id, start: parseYMD(trip.startDate) }))
+    .filter((trip) => !!trip.start && trip.start >= today)
+    .sort((a, b) => a.start - b.start)[0];
+
+  return next?.id || null;
+}
+
+export function findBestTripId(trips) {
+  const activeTripId = findActiveTripId(trips);
+  if (activeTripId) return activeTripId;
+
+  const nextTripId = findNextTripId(trips);
+  if (nextTripId) return nextTripId;
+
+  const latestPast = trips
+    .map((trip) => ({ id: trip.id, end: parseYMD(trip.endDate), start: parseYMD(trip.startDate) }))
+    .filter((trip) => !!trip.end || !!trip.start)
+    .sort((a, b) => {
+      const aTime = (a.end || a.start).getTime();
+      const bTime = (b.end || b.start).getTime();
+      return bTime - aTime;
+    })[0];
+
+  return latestPast?.id || null;
+}