feat: use friendly event date labels

src/lib/event-date-format.ts

@@ -0,0 +1,38 @@
+import {
+	format,
+	isSameDay,
+	isToday,
+	isTomorrow,
+	parseISO,
+} from "date-fns";
+import type { CalendarEvent } from "@/lib/types";
+
+const getFriendlyDayLabel = (value: Date): string => {
+	if (isToday(value)) return "Today";
+	if (isTomorrow(value)) return "Tomorrow";
+	return format(value, "MMM d, yyyy");
+};
+
+export const formatEventStartLabel = (start: string, allDay?: boolean): string => {
+	const parsed = parseISO(start);
+	const dayLabel = getFriendlyDayLabel(parsed);
+
+	if (allDay) return dayLabel;
+	return `${dayLabel} · ${format(parsed, "HH:mm")}`;
+};
+
+export const formatEventRangeLabel = (event: Pick<CalendarEvent, "start" | "end" | "allDay">): string => {
+	const startDate = parseISO(event.start);
+	const startLabel = getFriendlyDayLabel(startDate);
+
+	if (event.allDay || !event.end) {
+		return event.allDay ? startLabel : `${startLabel} · ${format(startDate, "HH:mm")}`;
+	}
+
+	const endDate = parseISO(event.end);
+	if (isSameDay(startDate, endDate)) {
+		return `${startLabel} · ${format(startDate, "HH:mm")}–${format(endDate, "HH:mm")}`;
+	}
+
+	return `${startLabel} · ${format(startDate, "HH:mm")} → ${getFriendlyDayLabel(endDate)} · ${format(endDate, "HH:mm")}`;
+};