package utils import ( "fmt" "time" ) func StartOfDay(date time.Time) time.Time { return FloorDate(date) } func StartOfToday(tz *time.Location) time.Time { return StartOfDay(FloorDate(time.Now().In(tz))) } func EndOfDay(date time.Time) time.Time { floored := FloorDate(date) if floored == date { date = date.Add(1 * time.Second) } return CeilDate(date) } func EndOfToday(tz *time.Location) time.Time { return EndOfDay(time.Now().In(tz)) } func StartOfThisWeek(tz *time.Location) time.Time { return StartOfWeek(time.Now().In(tz)) } func StartOfWeek(date time.Time) time.Time { year, week := date.ISOWeek() return firstDayOfISOWeek(year, week, date.Location()) } func StartOfThisMonth(tz *time.Location) time.Time { return StartOfMonth(time.Now().In(tz)) } func StartOfMonth(date time.Time) time.Time { return time.Date(date.Year(), date.Month(), 1, 0, 0, 0, 0, date.Location()) } func StartOfThisYear(tz *time.Location) time.Time { return StartOfYear(time.Now().In(tz)) } func StartOfYear(date time.Time) time.Time { return time.Date(date.Year(), time.January, 1, 0, 0, 0, 0, date.Location()) } // FloorDate rounds date down to the start of the day and keeps the time zone func FloorDate(date time.Time) time.Time { return time.Date(date.Year(), date.Month(), date.Day(), 0, 0, 0, 0, date.Location()) } // CeilDate rounds date up to the start of next day if date is not already a start (00:00:00) func CeilDate(date time.Time) time.Time { floored := FloorDate(date) if floored == date { return floored } return floored.Add(24 * time.Hour) } // SetLocation resets the time zone information of a date without converting it, i.e. 19:00 UTC will result in 19:00 CET, for instance func SetLocation(date time.Time, tz *time.Location) time.Time { return time.Date(date.Year(), date.Month(), date.Day(), 0, 0, 0, 0, tz) } // WithOffset adds the time zone difference between Local and tz to a date, i.e. 19:00 UTC will result in 21:00 CET (or 22:00 CEST), for instance func WithOffset(date time.Time, tz *time.Location) time.Time { now := time.Now() _, localOffset := now.Zone() _, targetOffset := now.In(tz).Zone() dateTz := date.Add(time.Duration((targetOffset - localOffset) * int(time.Second))) return time.Date(dateTz.Year(), dateTz.Month(), dateTz.Day(), dateTz.Hour(), dateTz.Minute(), dateTz.Second(), dateTz.Nanosecond(), dateTz.Location()).In(tz) } // SplitRangeByDays creates a slice of intervals between from and to, each of which is at max of 24 hours length and has its split at midnight func SplitRangeByDays(from time.Time, to time.Time) [][]time.Time { intervals := make([][]time.Time, 0) for t1 := from; t1.Before(to); { t2 := StartOfDay(t1).Add(24 * time.Hour) if t2.After(to) { t2 = to } intervals = append(intervals, []time.Time{t1, t2}) t1 = t2 } return intervals } func FmtWakatimeDuration(d time.Duration) string { d = d.Round(time.Minute) h := d / time.Hour d -= h * time.Hour m := d / time.Minute return fmt.Sprintf("%d hrs %d mins", h, m) } // https://stackoverflow.com/a/18632496 func firstDayOfISOWeek(year int, week int, timezone *time.Location) time.Time { date := time.Date(year, 0, 0, 0, 0, 0, 0, timezone) isoYear, isoWeek := date.ISOWeek() for date.Weekday() != time.Monday { // iterate back to Monday date = date.AddDate(0, 0, -1) isoYear, isoWeek = date.ISOWeek() } for isoYear < year { // iterate forward to the first day of the first week date = date.AddDate(0, 0, 1) isoYear, isoWeek = date.ISOWeek() } for isoWeek < week { // iterate forward to the first day of the given week date = date.AddDate(0, 0, 1) isoYear, isoWeek = date.ISOWeek() } return date }