@burglekitt/gmt/dist/plain/calculate/startOfQuarterForDateTime.js

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

import { Temporal } from "@js-temporal/polyfill";
import { isValidDateTime } from "../validate/index.js";
/**
 * Return the start of the quarter for a given ISO datetime.
 *
 * - Returns the first day of the quarter with time set to 00:00:00.
 * - Q1 returns "01-01T00:00:00", Q2 returns "04-01T00:00:00", etc.
 * - Validates input using isValidDateTime.
 *
 * @param value ISO PlainDateTime string
 * @returns ISO PlainDateTime string for the start of the quarter, or "" on invalid input
 *
 * @example startOfQuarterForDateTime("2024-03-15T12:00:00") // "2024-01-01T00:00:00"
 * @example startOfQuarterForDateTime("2024-06-15T12:00:00") // "2024-04-01T00:00:00"
 * @example startOfQuarterForDateTime("invalid") // ""
 */
export function startOfQuarterForDateTime(value) {
    if (!isValidDateTime(value)) {
        return "";
    }
    try {
        const dateTime = Temporal.PlainDateTime.from(value);
        const month = dateTime.month;
        const quarterStartMonth = Math.floor((month - 1) / 3) * 3 + 1;
        return dateTime
            .with({ month: quarterStartMonth, day: 1, hour: 0, minute: 0, second: 0 })
            .toString();
    }
    catch {
        return "";
    }
}