Make scheduling and dates timezone-safe

apps/web/src/lib/time-entry-display.ts

@@ -1,3 +1,8 @@
+import {
+  DEFAULT_TIME_ZONE,
+  getZonedDateTimeParts,
+} from "@beenvoice/domain/time-zone";
+
 export function invoiceLabel(inv: {
   invoicePrefix: string | null;
   invoiceNumber: string;
@@ -37,12 +42,13 @@ export type TimeEntryListItem = {
 
 export function groupEntriesByDate<T extends { startedAt: Date }>(
   entries: T[],
+  timeZone = DEFAULT_TIME_ZONE,
 ): { dateKey: string; label: string; entries: T[] }[] {
   const groups = new Map<string, T[]>();
 
   for (const entry of entries) {
-    const d = new Date(entry.startedAt);
-    const dateKey = `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, "0")}-${String(d.getDate()).padStart(2, "0")}`;
+    const parts = getZonedDateTimeParts(entry.startedAt, timeZone);
+    const dateKey = `${parts.year}-${String(parts.month).padStart(2, "0")}-${String(parts.day).padStart(2, "0")}`;
     const existing = groups.get(dateKey);
     if (existing) {
       existing.push(entry);
@@ -58,6 +64,7 @@ export function groupEntriesByDate<T extends { startedAt: Date }>(
       year: "numeric",
       month: "long",
       day: "numeric",
+      timeZone,
     });
     return { dateKey, label, entries: groupEntries };
   });