import type { Dayjs } from "@calcom/dayjs"; import dayjs from "@calcom/dayjs"; // converts a date to 2022-04-25 for example. export const yyyymmdd = (date: Date | Dayjs) => date instanceof Date ? dayjs(date).format("YYYY-MM-DD") : date.format("YYYY-MM-DD"); // @see: https://github.com/iamkun/dayjs/issues/1272 - for the reason we're not using dayjs to do this. export const daysInMonth = (date: Date | Dayjs) => { const [year, month] = date instanceof Date ? [date.getFullYear(), date.getMonth()] : [date.year(), date.month()]; // strange JS quirk: new Date(2022, 12, 0).getMonth() = 11 return new Date(year, month + 1, 0).getDate(); }; /** * Expects timeFormat to be either 12 or 24, if null or undefined * is passed in, we always default back to 24 hour notation. */ export const formatTime = ( date: string | Date | Dayjs, timeFormat?: number | null, timeZone?: string | null ) => { // console.log(timeZone, date); return timeZone ? dayjs(date) .tz(timeZone) .format(timeFormat === 12 ? "h:mma" : "HH:mm") : dayjs(date).format(timeFormat === 12 ? "h:mma" : "HH:mm"); }; /** * Checks if a provided timeZone string is recognized as a valid timezone by dayjs. * * @param {string} timeZone - The timezone string to be verified. * @returns {boolean} - Returns 'true' if the provided timezone string is recognized as a valid timezone by dayjs. Otherwise, returns 'false'. * */ export const isSupportedTimeZone = (timeZone: string) => { try { dayjs().tz(timeZone); return true; } catch (error) { return false; } }; /** * Returns a localized and translated date or time, based on the native * Intl.DateTimeFormat available to JS. Undefined values mean the browser's * locale will be used. */ export const formatLocalizedDateTime = ( date: Date | Dayjs, options: Intl.DateTimeFormatOptions = {}, locale: string | undefined = undefined ) => { const theDate = date instanceof dayjs ? (date as Dayjs).toDate() : (date as Date); return Intl.DateTimeFormat(locale, options).format(theDate); }; /** * Returns a localized and translated calendar day based on the * given Date object and locale. Undefined values mean the defaults * associated with the browser's current locale will be used. */ export const formatToLocalizedDate = ( date: Date | Dayjs, locale: string | undefined = undefined, dateStyle: Intl.DateTimeFormatOptions["dateStyle"] = "long", timeZone?: string ) => formatLocalizedDateTime(date, { dateStyle, timeZone }, locale); /** * Returns a localized and translated time of day based on the * given Date object and locale. Undefined values mean the defaults * associated with the browser's current locale will be used. */ export const formatToLocalizedTime = ( date: Date | Dayjs, locale: string | undefined = undefined, timeStyle: Intl.DateTimeFormatOptions["timeStyle"] = "short", hour12: Intl.DateTimeFormatOptions["hour12"] = undefined, timeZone?: string ) => formatLocalizedDateTime(date, { timeStyle, hour12, timeZone }, locale); /** * Returns a translated timezone based on the given Date object and * locale. Undefined values mean the browser's current locale * will be used. */ export const formatToLocalizedTimezone = ( date: Date | Dayjs, locale: string | undefined = undefined, timeZone: Intl.DateTimeFormatOptions["timeZone"], timeZoneName: Intl.DateTimeFormatOptions["timeZoneName"] = "long" ) => { // Intl.DateTimeFormat doesn't format into a timezone only, so we must // formatToParts() and return the piece we want const theDate = date instanceof dayjs ? (date as Dayjs).toDate() : (date as Date); return Intl.DateTimeFormat(locale, { timeZoneName, timeZone }) .formatToParts(theDate) .find((d) => d.type == "timeZoneName")?.value; }; /** * Sorts two timezones by their offset from GMT. */ export const sortByTimezone = (timezoneA: string, timezoneB: string) => { const timezoneAGmtOffset = dayjs.utc().tz(timezoneA).utcOffset(); const timezoneBGmtOffset = dayjs.utc().tz(timezoneB).utcOffset(); if (timezoneAGmtOffset === timezoneBGmtOffset) return 0; return timezoneAGmtOffset < timezoneBGmtOffset ? -1 : 1; }; /** * Verifies given time is a day before in timezoneB. */ export const isPreviousDayInTimezone = (time: string, timezoneA: string, timezoneB: string) => { const timeInTimezoneA = formatTime(time, 24, timezoneA); const timeInTimezoneB = formatTime(time, 24, timezoneB); if (time === timeInTimezoneB) return false; // Eg timeInTimezoneA = 12:00 and timeInTimezoneB = 23:00 const hoursTimezoneBIsLater = timeInTimezoneB.localeCompare(timeInTimezoneA) === 1; // If it is 23:00, does timezoneA come before or after timezoneB in GMT? const timezoneBIsEarlierTimezone = sortByTimezone(timezoneA, timezoneB) === 1; return hoursTimezoneBIsLater && timezoneBIsEarlierTimezone; }; /** * Verifies given time is a day after in timezoneB. */ export const isNextDayInTimezone = (time: string, timezoneA: string, timezoneB: string) => { const timeInTimezoneA = formatTime(time, 24, timezoneA); const timeInTimezoneB = formatTime(time, 24, timezoneB); if (time === timeInTimezoneB) return false; // Eg timeInTimezoneA = 12:00 and timeInTimezoneB = 09:00 const hoursTimezoneBIsEarlier = timeInTimezoneB.localeCompare(timeInTimezoneA) === -1; // If it is 09:00, does timezoneA come before or after timezoneB in GMT? const timezoneBIsLaterTimezone = sortByTimezone(timezoneA, timezoneB) === -1; return hoursTimezoneBIsEarlier && timezoneBIsLaterTimezone; }; const weekDays = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"] as const; type WeekDays = (typeof weekDays)[number]; type WeekDayIndex = 0 | 1 | 2 | 3 | 4 | 5 | 6; /** * Turns weekday string (eg "Monday") into a number (eg 1). * Also accepts a number as parameter (and straight returns that), and accepts * undefined as a parameter; returns 0 in that case. */ export const weekdayToWeekIndex = (weekday: WeekDays | string | number | undefined) => { if (typeof weekday === "undefined") return 0; if (typeof weekday === "number") return weekday >= 0 && weekday >= 6 ? (weekday as WeekDayIndex) : 0; return (weekDays.indexOf(weekday as WeekDays) as WeekDayIndex) || 0; }; /** * Dayjs does not expose the timeZone value publicly through .get("timeZone") * instead, we as devs are required to somewhat hack our way to get the * tz value as string * @param date Dayjs * @returns Time Zone name */ // eslint-disable-next-line @typescript-eslint/no-explicit-any export const getTimeZone = (date: Dayjs): string => (date as any)["$x"]["$timezone"]; /** * Verify if timeZone has Daylight Saving Time (DST). * * Many countries in the Northern Hemisphere. Daylight Saving Time usually starts in March-April and ends in * September-November when the countries return to standard time, or winter time as it is also known. * * In the Southern Hemisphere (south of the equator) the participating countries usually start the DST period * in September-November and end DST in March-April. * * @param timeZone Time Zone Name (Ex. America/Mazatlan) * @returns boolean */ export const timeZoneWithDST = (timeZone: string): boolean => { const jan = dayjs.tz(`${new Date().getFullYear()}-01-01T00:00:00`, timeZone); const jul = dayjs.tz(`${new Date().getFullYear()}-07-01T00:00:00`, timeZone); return jan.utcOffset() !== jul.utcOffset(); }; /** * Get DST difference. * Today clocks are almost always set one hour back or ahead. * However, on Lord Howe Island, Australia, clocks are set only 30 minutes forward * from LHST (UTC+10:30) to LHDT (UTC+11) during DST. * @param timeZone Time Zone Name (Ex. America/Mazatlan) * @returns minutes */ export const getDSTDifference = (timeZone: string): number => { const jan = dayjs.tz(`${new Date().getFullYear()}-01-01T00:00:00`, timeZone); const jul = dayjs.tz(`${new Date().getFullYear()}-07-01T00:00:00`, timeZone); return jul.utcOffset() - jan.utcOffset(); }; /** * Get UTC offset of given time zone when in DST * @param timeZone Time Zone Name (Ex. America/Mazatlan) * @returns minutes */ export const getUTCOffsetInDST = (timeZone: string) => { if (timeZoneWithDST(timeZone)) { const jan = dayjs.tz(`${new Date().getFullYear()}-01-01T00:00:00`, timeZone); const jul = dayjs.tz(`${new Date().getFullYear()}-07-01T00:00:00`, timeZone); return jan.utcOffset() < jul.utcOffset() ? jul.utcOffset() : jan.utcOffset(); } return 0; }; /** * Verifies if given time zone is in DST * @param date * @returns */ export const isInDST = (date: Dayjs) => { const timeZone = getTimeZone(date); return timeZoneWithDST(timeZone) && date.utcOffset() === getUTCOffsetInDST(timeZone); };