@burglekitt/gmt/dist/plain/get/getWeekOfYear.js

Temporal-based date and time utilities with timezone support and polyfill integration

import { Temporal } from "@js-temporal/polyfill";
import { getSystemTimeZone } from "../../zoned/get/getSystemTimeZone.js";
/**
 * Get the ISO week number of the current date.
 *
 * - Uses Temporal.Now.plainDateTimeISO to get current date in system timezone.
 * - Uses Temporal.PlainDate.weekOfYear for ISO week number.
 * - Returns null when system timezone is unavailable.
 *
 * @returns The ISO week number (1-53), or null on invalid
 *
 * @example getWeekOfYear() // 15
 * @example getWeekOfYear() // null (when system timeZone unavailable)
 */
export function getWeekOfYear() {
    const timeZone = getSystemTimeZone();
    if (!timeZone) {
        return null;
    }
    try {
        const now = Temporal.Now.plainDateTimeISO(timeZone);
        const date = Temporal.PlainDate.from({
            year: now.year,
            month: now.month,
            day: now.day,
        });
        return date.weekOfYear ?? null;
    }
    catch {
        return null;
    }
}