export type TimeUnit = 'millisecond' | 'second' | 'minute' | 'hour' | 'day' | 'week' | 'month' | 'quarter' | 'year';

export interface DateAdapter {
  // Override one or multiple of the methods to adjust to the logic of the current date library.
  override(members: Partial<DateAdapter>): void;
  readonly options: unknown;

  /**
   * Returns a map of time formats for the supported formatting units defined
   * in Unit as well as 'datetime' representing a detailed date/time string.
   * @returns {{string: string}}
   */
  formats(): { [key: string]: string };
  /**
   * Parses the given `value` and return the associated timestamp.
   * @param {unknown} value - the value to parse (usually comes from the data)
   * @param {string} [format] - the expected data format
   */
  parse(value: unknown, format?: TimeUnit): number | null;
  /**
   * Returns the formatted date in the specified `format` for a given `timestamp`.
   * @param {number} timestamp - the timestamp to format
   * @param {string} format - the date/time token
   * @return {string}
   */
  format(timestamp: number, format: TimeUnit): string;
  /**
   * Adds the specified `amount` of `unit` to the given `timestamp`.
   * @param {number} timestamp - the input timestamp
   * @param {number} amount - the amount to add
   * @param {Unit} unit - the unit as string
   * @return {number}
   */
  add(timestamp: number, amount: number, unit: TimeUnit): number;
  /**
   * Returns the number of `unit` between the given timestamps.
   * @param {number} a - the input timestamp (reference)
   * @param {number} b - the timestamp to subtract
   * @param {Unit} unit - the unit as string
   * @return {number}
   */
  diff(a: number, b: number, unit: TimeUnit): number;
  /**
   * Returns start of `unit` for the given `timestamp`.
   * @param {number} timestamp - the input timestamp
   * @param {Unit|'isoWeek'} unit - the unit as string
   * @param {number} [weekday] - the ISO day of the week with 1 being Monday
   * and 7 being Sunday (only needed if param *unit* is `isoWeek`).
   * @return {number}
   */
  startOf(timestamp: number, unit: TimeUnit | 'isoWeek', weekday?: number): number;
  /**
   * Returns end of `unit` for the given `timestamp`.
   * @param {number} timestamp - the input timestamp
   * @param {Unit|'isoWeek'} unit - the unit as string
   * @return {number}
   */
  endOf(timestamp: number, unit: TimeUnit | 'isoWeek'): number;
}

export const _adapters: {
  _date: DateAdapter;
};