package timerange

import (
	"math"
	"time"
)

type TimeRange struct {
	Head time.Time
	Tail time.Time
}

func (t *TimeRange) HeadAddDay(d time.Duration) TimeRange {
	return TimeRange{
		Head: t.Head.Add(d),
		Tail: t.Tail,
	}
}

func (t *TimeRange) TailAddDay(d time.Duration) TimeRange {
	return TimeRange{
		Head: t.Head,
		Tail: t.Tail.Add(d),
	}
}

func (t *TimeRange) TotalDays() int64 {
	return int64(math.Floor(float64(t.Tail.Sub(t.Head).Hours() / 24)))
}

func (t *TimeRange) SplitByMinute(minute int64) []TimeRange {
	count := int(t.Tail.Sub(t.Head)/time.Minute) / int(minute)
	var split = make([]TimeRange, 0, count)
	temp := t.Head
	if t.Tail.After(temp) {
		sub := temp.Add(time.Duration(minute) * time.Minute)
		if sub.After(t.Tail) { //防止tail超出设定值
			sub = t.Tail
		}
		subRange := TimeRange{ //一个切片
			Head: temp,
			Tail: sub,
		}
		split = append(split, subRange)
		temp = sub
	}
	return split
}

// LocDayRange 本地当日时间范围
func LocDayRange(position time.Time) TimeRange {
	head := time.Date(position.Year(), position.Month(), position.Day(), 0, 0, 0, 0, position.Location()).In(time.Local)
	tail := head.AddDate(0, 0, 1)
	return TimeRange{
		Head: head,
		Tail: tail,
	}
}

// LocDayRange 本地当月时间范围
func LocMonthRange(position time.Time) TimeRange {
	head := time.Date(position.Year(), position.Month(), 1, 0, 0, 0, 0, position.Location()).In(time.Local)
	tail := head.AddDate(0, 1, 0)
	return TimeRange{
		Head: head,
		Tail: tail,
	}
}

func RecentMinute(tim time.Time, scaleMinute int64) time.Time {
	minute := int64(tim.Minute())
	lave := minute % scaleMinute
	formatMinute := minute - lave
	return time.Date(tim.Year(), tim.Month(), tim.Day(), tim.Hour(), int(formatMinute), 0, 0, tim.Location())
}

func RecentSecond(tim time.Time, scaleSecond int64) time.Time {
	second := int64(tim.Second())
	lave := second % scaleSecond
	formatSecond := second - lave
	return time.Date(tim.Year(), tim.Month(), tim.Day(), tim.Hour(), tim.Minute(), int(formatSecond), 0, tim.Location())
}