text: import startOfWeek from "../startOfWeek/index.js";
  import toDate from "../toDate/index.js";
  import toInteger from "../_lib/toInteger/index.js";
  import requiredArgs from "../_lib/requiredArgs/index.js";
  /**
   * @name getWeekYear
   * @category Week-Numbering Year Helpers
   * @summary Get the local week-numbering year of the given date.
   *
   * @description
   * Get the local week-numbering year of the given date.
   * The exact calculation depends on the values of
   * `options.weekStartsOn` (which is the index of the first day of the week)
   * and `options.firstWeekContainsDate` (which is the day of January, which is always in
   * the first week of the week-numbering year)
   *
   * Week numbering: https://en.wikipedia.org/wiki/Week#Week_numbering
   *
   * ### v2.0.0 breaking changes:
   *
   * - [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes).
   *
   * @param {Date|Number} date - the given date
   * @param {Object} [options] - an object with options.
   * @param {Locale} [options.locale=defaultLocale] - the locale object. See [Locale]{@link https://date-fns.org/docs/Locale}
   * @param {0|1|2|3|4|5|6} [options.weekStartsOn=0] - the index of the first day of the week (0 - Sunday)
   * @param {1|2|3|4|5|6|7} [options.firstWeekContainsDate=1] - the day of January, which is always in the first week of the year
   * @returns {Number} the local week-numbering year
   * @throws {TypeError} 1 argument required
   * @throws {RangeError} `options.weekStartsOn` must be between 0 and 6
   * @throws {RangeError} `options.firstWeekContainsDate` must be between 1 and 7
   *
   * @example
   * // Which week numbering year is 26 December 2004 with the default settings?
   * var result = getWeekYear(new Date(2004, 11, 26))
   * //=> 2005
   *
   * @example
   * // Which week numbering year is 26 December 2004 if week starts on Saturday?
   * var result = getWeekYear(new Date(2004, 11, 26), { weekStartsOn: 6 })
   * //=> 2004
   *
   * @example
   * // Which week numbering year is 26 December 2004 if the first week contains 4 January?
   * var result = getWeekYear(new Date(2004, 11, 26), { firstWeekContainsDate: 4 })
   * //=> 2004
   */
  
  export default function getWeekYear(dirtyDate, dirtyOptions) {
    requiredArgs(1, arguments);
    var date = toDate(dirtyDate);
    var year = date.getFullYear();
    var options = dirtyOptions || {};
    var locale = options.locale;
    var localeFirstWeekContainsDate = locale && locale.options && locale.options.firstWeekContainsDate;
    var defaultFirstWeekContainsDate = localeFirstWeekContainsDate == null ? 1 : toInteger(localeFirstWeekContainsDate);
    var firstWeekContainsDate = options.firstWeekContainsDate == null ? defaultFirstWeekContainsDate : toInteger(options.firstWeekContainsDate); // Test if weekStartsOn is between 1 and 7 _and_ is not NaN
  
    if (!(firstWeekContainsDate >= 1 && firstWeekContainsDate <= 7)) {
      throw new RangeError('firstWeekContainsDate must be between 1 and 7 inclusively');
    }
  
    var firstWeekOfNextYear = new Date(0);
    firstWeekOfNextYear.setFullYear(year + 1, 0, firstWeekContainsDate);
    firstWeekOfNextYear.setHours(0, 0, 0, 0);
    var startOfNextYear = startOfWeek(firstWeekOfNextYear, dirtyOptions);
    var firstWeekOfThisYear = new Date(0);
    firstWeekOfThisYear.setFullYear(year, 0, firstWeekContainsDate);
    firstWeekOfThisYear.setHours(0, 0, 0, 0);
    var startOfThisYear = startOfWeek(firstWeekOfThisYear, dirtyOptions);
  
    if (date.getTime() >= startOfNextYear.getTime()) {
      return year + 1;
    } else if (date.getTime() >= startOfThisYear.getTime()) {
      return year;
    } else {
      return year - 1;
    }
  }