nepali-heroui-calendar

A custom Bikram Sambat (BS) calendar adapter for @internationalized/date and HeroUI / React Aria <Calendar> components.

Instead of re-implementing date maths from scratch, this package bridges Adobe's calendar primitives with the battle-tested lookup tables in nepali-date-converter.

Heads-up: Because the converter is table-driven, the supported range is 2000–2090 BS (≈ 1943 Apr – 2034 Apr AD). Dates outside this range will throw.

Installation

npm install nepali-heroui-calendar

Peer dependencies (your project should already have them if you use HeroUI):

npm install react react-dom @heroui/react @internationalized/date

Usage

1. Drop-in HeroUI Calendar

import { NepaliCalendar, todayNepali } from "nepali-heroui-calendar";

export default function App() {
  return (
    <NepaliCalendar
      aria-label="Nepali Date"
      defaultValue={todayNepali()}
    />
  );
}

2. Use the adapter directly with @internationalized/date

import { CalendarDate, toCalendar, today, getLocalTimeZone } from "@internationalized/date";
import { NepaliCalendarAdapter } from "nepali-heroui-calendar";

const nepali = new NepaliCalendarAdapter();

// Create a BS date
const bsDate = new CalendarDate(nepali, "BS", 2081, 5, 15);

// Convert gregorian "today" to BS
const gToday = today(getLocalTimeZone());
const bsToday = toCalendar(gToday, nepali);

console.log(bsToday.toString()); // 2081-05-15

3. Lower-level helpers

import {
  createCalendarDate,
  toNepaliDate,
  formatDate,
  toNepaliNumerals,
  NEPALI_MONTHS,
} from "nepali-heroui-calendar";

const d = createCalendarDate(2081, 1, 15);

// format with nepali-date-converter patterns
formatDate(d, "ddd DD, MMMM YYYY"); // "Saturday 15, Baisakh 2081"

// convert to a NepaliDate instance (from nepali-date-converter)
const nd = toNepaliDate(d);
nd.format("YYYY/MM/DD", "np"); // "२०८१/०१/१५"

toNepaliNumerals(2081); // "२०८१"

API

NepaliCalendarAdapter (class)

Implements the Calendar interface from @internationalized/date.

| Method | Description | | ------------------- | ----------------------------------------------------- | | fromJulianDay(jd) | JD → BS CalendarDate | | toJulianDay(date) | BS AnyCalendarDate → JD | | getDaysInMonth(d) | Days in that BS month (looked up from converter) | | getMonthsInYear() | Always 12 | | getYearsInEra() | 2090 (last supported year) | | getEras() | ["BS"] |

NepaliCalendar (React component)

A thin wrapper around HeroUI's <Calendar> that pre-binds the Nepali adapter. Accepts all CalendarProps except calendar.

Helpers

| Helper | Return type | Description | | ------------------ | ----------- | ---------------------------------- | | todayNepali() | CalendarDate | Today's date in BS | | createCalendarDate(y,m,d) | CalendarDate | BS CalendarDate factory | | toNepaliDate(d) | NepaliDate | Convert to converter instance | | formatDate(d,fmt)| string | Format via converter | | toNepaliNumerals()| string | 0–9 → Nepali digits |

Limitations & Caveats

1. Supported range: 2000–2090 BS. The adapter throws outside this range.
2. No CLDR identifier: "nepali" is not a standard CalendarIdentifier, so createCalendar("nepali") won't work. Always instantiate the class directly: new NepaliCalendarAdapter().
3. Heading text: HeroUI's <CalendarHeading> currently renders in the active locale using @internationalized/date's DateFormatter, which does not know Nepali month names. If you need Nepali month labels in the header you can compose your own heading with the useNepaliMonthLabels() hook.

License

MIT