@burglekitt/gmt/dist/zoned/calculate/roundZoned.js

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

import { Temporal } from "@js-temporal/polyfill";
import { isValidZonedDateTime } from "../validate/index.js";
/**
 * Round an ISO 8601 zoned datetime string to the specified unit.
 *
 * - Returns "" for invalid inputs.
 * - Accepts "day" and time units: "hour", "minute", "second", "millisecond", "microsecond", "nanosecond".
 * - Date units ("year", "month", "week") are not supported by the Temporal polyfill's ZonedDateTime.round() — they return "".
 * - Wraps Temporal.ZonedDateTime.round() which throws on invalid options.
 * - Note: The polyfill's `.round()` does not support `disambiguation` or `offset` options.
 *
 * @param value ISO 8601 zoned datetime string
 * @param options Rounding options: smallestUnit, optional roundingIncrement, roundingMode
 * @returns Rounded ISO 8601 zoned datetime string, or "" on invalid input
 *
 * @example roundZoned("2024-06-15T12:34:56-05:00[America/New_York]", { smallestUnit: "hour" }) // "2024-06-15T13:00:00-05:00[America/New_York]"
 * @example roundZoned("2024-06-15T12:34:56-05:00[America/New_York]", { smallestUnit: "minute", roundingIncrement: 15 }) // "2024-06-15T12:45:00-05:00[America/New_York]"
 * @example roundZoned("invalid", { smallestUnit: "hour" }) // ""
 */
export function roundZoned(value, options) {
    const { smallestUnit, roundingIncrement, roundingMode } = options;
    if (!isValidZonedDateTime(value))
        return "";
    // Polyfill limitation: year/month/week not supported for ZonedDateTime.round()
    const supportedUnits = [
        "day",
        "hour",
        "minute",
        "second",
        "millisecond",
        "microsecond",
        "nanosecond",
    ];
    if (!supportedUnits.includes(smallestUnit))
        return "";
    try {
        const source = Temporal.ZonedDateTime.from(value);
        const result = source.round({
            smallestUnit,
            roundingIncrement,
            roundingMode,
        });
        // Handle default precision: 0 for > sec, 3 for ms, 6 for µs, 9 for ns
        const precisionMap = {
            millisecond: 3,
            microsecond: 6,
            nanosecond: 9,
        };
        const fractionalDigits = precisionMap[smallestUnit] || 0;
        return result.toString({ fractionalSecondDigits: fractionalDigits });
    }
    catch {
        return "";
    }
}