@timestamp-js/calendar-saka

@timestamp-js/calendar-saka

Indian National Calendar (Saka) adapter for @timestamp-js/core.

The adapter is indianNationalCalendar, with sakaCalendar as a convenience alias. It models the official Indian National Calendar using deterministic Gregorian-aligned leap-year rules.

import {
  createCalendarDayList,
  getCalendarEndOfMonth,
  getCalendarEndOfWeek,
  getCalendarStartOfMonth,
  getCalendarStartOfWeek,
  gregorianCalendar,
  parseCalendarTimestamp,
} from '@timestamp-js/core'
import { indianNationalCalendar } from '@timestamp-js/calendar-saka'

const sakaNewYear = { year: 1946, month: 1, day: 1 }
const gregorian = gregorianCalendar.fromEpochDay(indianNationalCalendar.toEpochDay(sakaNewYear))

gregorian // { year: 2024, month: 3, day: 21 }

const visible = parseCalendarTimestamp('1946-01-15', indianNationalCalendar)!
const weekdays = [0, 1, 2, 3, 4, 5, 6]

const weekStart = getCalendarStartOfWeek(visible, weekdays, indianNationalCalendar)
const weekEnd = getCalendarEndOfWeek(visible, weekdays, indianNationalCalendar)
const weekDays = createCalendarDayList(weekStart, weekEnd, visible, indianNationalCalendar)

weekStart.date // '1946-01-11'
weekEnd.date // '1946-01-17'
weekDays.length // 7

const monthStart = getCalendarStartOfMonth(visible, indianNationalCalendar)
const monthEnd = getCalendarEndOfMonth(visible, indianNationalCalendar)
const monthDays = createCalendarDayList(monthStart, monthEnd, visible, indianNationalCalendar)

monthStart.date // '1946-01-01'
monthEnd.date // '1946-01-31'
monthDays.length // 31

Browser Globals

For CDN or CodePen usage, load @timestamp-js/core before the adapter package:

<script src="https://cdn.jsdelivr.net/npm/@timestamp-js/core@0.1.0-rc.4/dist/index.global.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/@timestamp-js/calendar-saka@0.1.0-rc.4/dist/index.global.min.js"></script>
<script>
  const visible = TimestampJsCore.parseCalendarTimestamp(
    '1946-01-15',
    TimestampJsCalendarSaka.indianNationalCalendar,
  )

  console.log(visible?.calendarId)
</script>

This package is early calendar-adapter work. Treat the adapter contract as release-candidate API until @timestamp-js/core reaches a stable 1.0.0.