/** Returns whether the value is a valid 24-hour `HH:mm` time. */
export declare const isValidTime: (value: string | undefined) => value is string;
/**
 * Splits a `HH:mm` time into its hour and minute parts.
 * Returns `undefined` when the value is empty or invalid.
 */
export declare const splitTime: (value: string | undefined) => {
    hour: string;
    minute: string;
} | undefined;
/** Builds a `HH:mm` time from an hour and a minute. */
export declare const joinTime: (hour: string, minute: string) => string;
/**
 * Lists the hours of the day as two-digit strings, every `step` hours.
 * Invalid steps fall back to one hour.
 */
export declare const getHourOptions: (step?: number) => string[];
/**
 * Lists the minutes of an hour as two-digit strings, every `step` minutes.
 * Invalid steps fall back to one minute.
 */
export declare const getMinuteOptions: (step: number) => string[];
/**
 * Returns whether a time sits within the optional `min` and `max` bounds
 * (inclusive). Invalid bounds are ignored.
 */
export declare const isTimeInRange: (time: string, min?: string, max?: string) => boolean;
/** Moves a time to the nearest bound when it falls outside the range. */
export declare const clampTime: (time: string, min?: string, max?: string) => string;
/** Returns the current local time as `HH:mm`. */
export declare const getCurrentTime: (now?: Date) => string;