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import toDate from "../toDate/index.js" ;
import toInteger from "../_lib/toInteger/index.js" ;
import requiredArgs from "../_lib/requiredArgs/index.js" ;
/**
* @name startOfWeek
* @category Week Helpers
* @summary Return the start of a week for the given date.
*
* @description
* Return the start of a week for the given date.
* The result will be in the local timezone.
*
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* ### 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).
*
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* @param {Date|Number} date - the original 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)
* @returns {Date} the start of a week
* @throws {TypeError} 1 argument required
* @throws {RangeError} `options.weekStartsOn` must be between 0 and 6
*
* @example
* // The start of a week for 2 September 2014 11:55:00:
* const result = startOfWeek(new Date(2014, 8, 2, 11, 55, 0))
* //=> Sun Aug 31 2014 00:00:00
*
* @example
* // If the week starts on Monday, the start of the week for 2 September 2014 11:55:00:
* const result = startOfWeek(new Date(2014, 8, 2, 11, 55, 0), { weekStartsOn: 1 })
* //=> Mon Sep 01 2014 00:00:00
*/
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export default function startOfWeek ( dirtyDate , dirtyOptions ) {
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requiredArgs ( 1 , arguments ) ;
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var options = dirtyOptions || { } ;
var locale = options . locale ;
var localeWeekStartsOn = locale && locale . options && locale . options . weekStartsOn ;
var defaultWeekStartsOn = localeWeekStartsOn == null ? 0 : toInteger ( localeWeekStartsOn ) ;
var weekStartsOn = options . weekStartsOn == null ? defaultWeekStartsOn : toInteger ( options . weekStartsOn ) ; // Test if weekStartsOn is between 0 and 6 _and_ is not NaN
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if ( ! ( weekStartsOn >= 0 && weekStartsOn <= 6 ) ) {
throw new RangeError ( 'weekStartsOn must be between 0 and 6 inclusively' ) ;
}
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var date = toDate ( dirtyDate ) ;
var day = date . getDay ( ) ;
var diff = ( day < weekStartsOn ? 7 : 0 ) + day - weekStartsOn ;
date . setDate ( date . getDate ( ) - diff ) ;
date . setHours ( 0 , 0 , 0 , 0 ) ;
return date ;
}