feat: replace Date constructor with parseISO for improved date handling across calendar components #25

components/calendar/calendar-agenda-view.tsx

@@ -49,7 +49,7 @@ export function CalendarAgendaView({
 
   const grouped = useMemo(() => {
     const sorted = [...events].sort((a, b) =>
-      new Date(a.start).getTime() - new Date(b.start).getTime()
+      parseISO(a.start).getTime() - parseISO(b.start).getTime()
     );
 
     const groups: DayGroup[] = [];

components/calendar/calendar-month-view.tsx

@@ -121,13 +121,14 @@ export function CalendarMonthView({
     try {
       const data = JSON.parse(json);
       const originalStart = parseISO(data.originalStart);
+      const event = useCalendarStore.getState().events.find(e => e.id === data.eventId);
+      const isAllDay = event?.showWithoutTime;
       const newStart = new Date(day);
       newStart.setHours(originalStart.getHours(), originalStart.getMinutes(), originalStart.getSeconds(), 0);
-      const newStartISO = format(newStart, "yyyy-MM-dd'T'HH:mm:ss");
+      const newStartISO = isAllDay ? format(newStart, "yyyy-MM-dd") : format(newStart, "yyyy-MM-dd'T'HH:mm:ss");
       if (newStartISO === data.originalStart) return;
       const client = useAuthStore.getState().client;
       if (!client) return;
-      const event = useCalendarStore.getState().events.find(e => e.id === data.eventId);
       const hasParticipants = event?.participants && Object.keys(event.participants).length > 0;
       await useCalendarStore.getState().updateEvent(client, data.eventId, { start: newStartISO }, hasParticipants || undefined);
     } catch {

components/calendar/event-modal.tsx

@@ -262,10 +262,10 @@ export function EventModal({
     if (trimmedTitle.length > 500 || description.trim().length > 10000 || location.trim().length > 500) return;
 
     const startStr = allDay
-      ? `${startDate}T00:00:00`
+      ? startDate
       : `${startDate}T${startTime}:00`;
 
-    const start = new Date(startStr);
+    const start = allDay ? parseISO(startStr) : new Date(startStr);
     let duration: string;
 
     if (allDay) {
@@ -393,7 +393,7 @@ export function EventModal({
       uid: newUid,
       title: event.title,
       description: event.description,
-      start: format(newStart, "yyyy-MM-dd'T'HH:mm:ss"),
+      start: event.showWithoutTime ? format(newStart, "yyyy-MM-dd") : format(newStart, "yyyy-MM-dd'T'HH:mm:ss"),
       duration: event.duration,
       timeZone: event.timeZone,
       showWithoutTime: event.showWithoutTime,

components/calendar/mini-calendar.tsx

@@ -7,7 +7,7 @@ import {
   startOfMonth, endOfMonth, startOfWeek, endOfWeek,
   addMonths, subMonths, addYears, subYears, setMonth, setYear,
   eachDayOfInterval, getMonth, getYear, getISOWeek, getWeek,
-  isSameDay, isSameMonth, isToday, format,
+  isSameDay, isSameMonth, isToday, format, parseISO,
 } from "date-fns";
 import { cn } from "@/lib/utils";
 import type { CalendarEvent } from "@/lib/jmap/types";
@@ -54,7 +54,7 @@ export function MiniCalendar({
   const eventDates = useMemo(() => {
     const set = new Set<string>();
     events.forEach(e => {
-      try { set.add(format(new Date(e.start), "yyyy-MM-dd")); } catch { /* skip */ }
+      try { set.add(format(parseISO(e.start), "yyyy-MM-dd")); } catch { /* skip */ }
     });
     return set;
   }, [events]);

components/calendar/task-modal.tsx

@@ -97,7 +97,7 @@ export function TaskModal({
           due = `${dueDate}T${dueTime}:00`;
           showWithoutTime = false;
         } else {
-          due = `${dueDate}T00:00:00`;
+          due = dueDate;
           showWithoutTime = true;
         }
       }