first commit

calcom/packages/lib/weekday.ts

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+type WeekdayFormat = "short" | "long";
+
+// By default starts on Sunday (Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday)
+export function weekdayNames(locale: string | string[], weekStart = 0, format: WeekdayFormat = "long") {
+  return Array(7)
+    .fill(null)
+    .map((_, day) => nameOfDay(locale, day + weekStart, format));
+}
+
+export function nameOfDay(
+  locale: string | string[] | undefined,
+  day: number,
+  format: WeekdayFormat = "long"
+) {
+  return new Intl.DateTimeFormat(locale, { weekday: format }).format(new Date(1970, 0, day + 4));
+}