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

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

import { Temporal } from "@js-temporal/polyfill";
import { isValidAmount, resolveOverflow } from "../../internal/index.js";
import { isValidTime, isValidTimeDurationUnit } from "../validate/index.js";
/**
 * Return a PlainTime ISO string with `units` subtracted from `value`.
 *
 * - Validates `value`, `units`, and `amount` before performing the subtract.
 * - Returns "" for invalid inputs.
 *
 * `overflow` ("constrain" (default) | "reject") is accepted for API consistency with sibling
 * subtract functions, but PlainTime arithmetic always wraps around the clock (e.g. 01:00 - 2 hours
 * = 23:00) rather than producing an out-of-range value, so it has no observable effect here.
 *
 * @param value ISO PlainTime string
 * @param units Partial<Record<TimeDurationUnit, number>> object specifying units to subtract
 * @param options optional: overflow ("constrain" | "reject" — accepted but inert, see above)
 * @returns ISO PlainTime string after subtraction, or "" on invalid input
 *
 * @example subtractTime("14:30:00", { hours: 1 }) // "13:30:00"
 * @example subtractTime("invalid", { hours: 1 }) // ""
 */
export function subtractTime(value, units, options) {
    const validTime = isValidTime(value);
    const validUnits = Object.keys(units).every(isValidTimeDurationUnit);
    const validAmounts = Object.values(units).every(isValidAmount);
    if (!validTime || !validUnits || !validAmounts) {
        return "";
    }
    try {
        const time = Temporal.PlainTime.from(value);
        return time
            .subtract(units, { overflow: resolveOverflow(options?.overflow) })
            .toString();
    }
    catch {
        return "";
    }
}