r = Math.min(...years); - const maxYear = Math.max(...years); - - for (let hy = minYear - 20; hy <= maxYear + 20; hy++) { - const monthSubMap = new Map(); - - for (let hm = 1; hm <= 12; hm++) { - let length: 29 | 30; - - const yearData = raw[hy as TSupportedHijriYear]; - if (yearData && hm <= yearData.length) { - length = yearData[hm - 1] as 29 | 30; - } else { - length = computedMonthLength(hy, hm); - } - - monthSubMap.set(hm, length); - } - - monthMap.set(hy, monthSubMap); - } - - return monthMap; -} - -function isHijriLeapYear(hy: number): boolean { - const y = ((hy - 1) % 30) + 1; - return [2, 5, 7, 10, 13, 16, 18, 21, 24, 26, 29].includes(y); -} - -function computedMonthLength(hy: number, hm: number): 29 | 30 { - if (hm === 12) return isHijriLeapYear(hy) ? 30 : 29; - return hm % 2 === 1 ? 30 : 29; -} - -function getMonthLength(hy: number, hm: number): 29 | 30 { - const known = HIJRI_MONTH_MAP.get(hy)?.get(hm); - if (known) return known; - - return computedMonthLength(hy, hm); -} - -function gregorianToJulian(year: number, month: number, day: number): number { - if (month < 3) { - year -= 1; - month += 12; +import { + CalendarDate, + IslamicUmalquraCalendar, + toCalendar, + GregorianCalendar, +} from "@internationalized/date"; +import type { THijri, TGregorian, THijriBase } from "src/types"; +import { IRAN_HIJRI_MONTHS, IRAN_HIJRI_ANCHOR } from "src/constants"; + +const HIJRI_MONTH_MAP = buildHijriMonthMap(IRAN_HIJRI_MONTHS); +function buildHijriMonthMap(raw: Record) { + const map = new Map>(); + + for (const [yearStr, months] of Object.entries(raw)) { + const year = Number(yearStr); + const sub = new Map(); + + months.forEach((len, i) => { + sub.set(i + 1, len as 29 | 30); + }); + + map.set(year, sub); } - const a = Math.floor(year / 100); - const b = - year === 1582 && (month > 10 || (month === 10 && day > 4)) - ? -10 - : year > 1582 - ? 2 - a + Math.floor(a / 4) - : 0; - - return Math.floor(365.25 * (year + 4716)) + Math.floor(30.6001 * (month + 1)) + day + b - 1524; + return map; } -function julianToGregorian(julianDay: number): TGregorian { - let b = 0; - - if (julianDay > 2299160) { - const a = Math.floor((julianDay - 1867216.25) / 36524.25); - b = 1 + a - Math.floor(a / 4); - } - - const julday = julianDay + b + 1524; - let c = Math.floor((julday - 122.1) / 365.25); - const d = Math.floor(365.25 * c); - const e = Math.floor((julday - d) / 30.6001); - - const gd = julday - d - Math.floor(30.6001 * e); - const gm = e > 13 ? e - 13 : e - 1; - const gy = gm > 2 ? c - 4716 : c - 4715; - - return { gy, gm, gd }; -} +//? Iran conversions +function gregorianToHijriIran(gy: number, gm: number, gd: number): THijri { + const target = new CalendarDate(gy, gm, gd); -function pickNearestAnchorByJulian(jd: number) { - let best = HIJRI_ANCHORS.first; - let minDelta = Math.abs( - jd - gregorianToJulian(best.gregorian.gy, best.gregorian.gm, best.gregorian.gd), + const anchorG = new CalendarDate( + IRAN_HIJRI_ANCHOR.gy, + IRAN_HIJRI_ANCHOR.gm, + IRAN_HIJRI_ANCHOR.gd, ); - for (const a of [HIJRI_ANCHORS.last]) { - const ajd = gregorianToJulian(a.gregorian.gy, a.gregorian.gm, a.gregorian.gd); - const d = Math.abs(jd - ajd); - if (d < minDelta) { - best = a; - minDelta = d; - } - } - - return best; -} - -function pickNearestAnchorByHijri(hy: number, hm: number) { - const first = HIJRI_ANCHORS.first; - const last = HIJRI_ANCHORS.last; - - const d1 = Math.abs(hy - first.hijri.hy) * 12 + Math.abs(hm - first.hijri.hm); - const d2 = Math.abs(hy - last.hijri.hy) * 12 + Math.abs(hm - last.hijri.hm); - - return d1 <= d2 ? first : last; -} - -//? --- Main --- -export function gregorianToHijri(gy: number, gm: number, gd: number): THijri { - const jd = gregorianToJulian(gy, gm, gd); - const anchor = pickNearestAnchorByJulian(jd); + let delta = target.compare(anchorG); - let { hy, hm, hd } = anchor.hijri; - let ajd = gregorianToJulian(anchor.gregorian.gy, anchor.gregorian.gm, anchor.gr

Persian Calendar