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import startOfWeek from '../startOfWeek/index.ts'import toDate from '../toDate/index.ts'import toInteger from '../_lib/toInteger/index.ts'import requiredArgs from '../_lib/requiredArgs/index.ts'import {  WeekStartOptions,  LocaleOptions,  FirstWeekContainsDateOptions,} from '../types.ts'
/** * @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? * const result = getWeekYear(new Date(2004, 11, 26)) * //=> 2005 * * @example * // Which week numbering year is 26 December 2004 if week starts on Saturday? * const 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? * const result = getWeekYear(new Date(2004, 11, 26), { firstWeekContainsDate: 4 }) * //=> 2004 */export default function getWeekYear(  dirtyDate: Date | number,  options?: LocaleOptions & WeekStartOptions & FirstWeekContainsDateOptions): number {  requiredArgs(1, arguments)
  const date = toDate(dirtyDate)  const year = date.getFullYear()
  const localeFirstWeekContainsDate =    options?.locale?.options?.firstWeekContainsDate  const defaultFirstWeekContainsDate =    localeFirstWeekContainsDate == null      ? 1      : toInteger(localeFirstWeekContainsDate)  const 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'    )  }
  const firstWeekOfNextYear = new Date(0)  firstWeekOfNextYear.setFullYear(year + 1, 0, firstWeekContainsDate)  firstWeekOfNextYear.setHours(0, 0, 0, 0)  const startOfNextYear = startOfWeek(firstWeekOfNextYear, options)
  const firstWeekOfThisYear = new Date(0)  firstWeekOfThisYear.setFullYear(year, 0, firstWeekContainsDate)  firstWeekOfThisYear.setHours(0, 0, 0, 0)  const startOfThisYear = startOfWeek(firstWeekOfThisYear, options)
  if (date.getTime() >= startOfNextYear.getTime()) {    return year + 1  } else if (date.getTime() >= startOfThisYear.getTime()) {    return year  } else {    return year - 1  }}