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ngx-bootstrap

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import { createUTCDate } from '../create/date-from-array'; import { daysInYear } from './year'; import { getDayOfYear } from './day-of-year'; import { getFullYear } from '../utils/date-getters'; function firstWeekOffset(year, dow, doy) { // first-week day -- which january is always in the first week (4 for iso, 1 for other) var fwd = dow - doy + 7; // first-week day local weekday -- which local weekday is fwd var fwdlw = (createUTCDate(year, 0, fwd).getUTCDay() - dow + 7) % 7; return -fwdlw + fwd - 1; } // https://en.wikipedia.org/wiki/ISO_week_date#Calculating_a_date_given_the_year.2C_week_number_and_weekday export function dayOfYearFromWeeks(year, week, weekday, dow, doy) { var localWeekday = (7 + weekday - dow) % 7; var weekOffset = firstWeekOffset(year, dow, doy); var dayOfYear = 1 + 7 * (week - 1) + localWeekday + weekOffset; var resYear; var resDayOfYear; if (dayOfYear <= 0) { resYear = year - 1; resDayOfYear = daysInYear(resYear) + dayOfYear; } else if (dayOfYear > daysInYear(year)) { resYear = year + 1; resDayOfYear = dayOfYear - daysInYear(year); } else { resYear = year; resDayOfYear = dayOfYear; } return { year: resYear, dayOfYear: resDayOfYear }; } export function weekOfYear(date, dow, doy, isUTC) { var weekOffset = firstWeekOffset(getFullYear(date, isUTC), dow, doy); var week = Math.floor((getDayOfYear(date, isUTC) - weekOffset - 1) / 7) + 1; var resWeek; var resYear; if (week < 1) { resYear = getFullYear(date, isUTC) - 1; resWeek = week + weeksInYear(resYear, dow, doy); } else if (week > weeksInYear(getFullYear(date, isUTC), dow, doy)) { resWeek = week - weeksInYear(getFullYear(date, isUTC), dow, doy); resYear = getFullYear(date, isUTC) + 1; } else { resYear = getFullYear(date, isUTC); resWeek = week; } return { week: resWeek, year: resYear }; } export function weeksInYear(year, dow, doy) { var weekOffset = firstWeekOffset(year, dow, doy); var weekOffsetNext = firstWeekOffset(year + 1, dow, doy); return (daysInYear(year) - weekOffset + weekOffsetNext) / 7; } //# sourceMappingURL=week-calendar-utils.js.map