package time_arrow

import (
	"errors"
	"fmt"
	"github.com/google/uuid"
	"log"
	"sort"
	"strings"
	"time"
)

type TimeArrowType string

const (
	TimeArrowTypeDayOfWeek  TimeArrowType = "DAY_OF_WEEK"
	TimeArrowTypeDayOfMonth TimeArrowType = "DAY_OF_MONTH"
	TimeArrowTypeDateSlice  TimeArrowType = "DATE_SLICE"
)

type DateSlice struct {
	Start string `json:"start"`
	End   string `json:"end"`
}

type TimeArrow struct {
	TimeArrowId string        `json:"time_arrow_id"`
	Group       string        `json:"group"`
	Type        TimeArrowType `json:"type"`
	//可选
	DayOfWeek  []int       `json:"day_of_week"`
	DayOfMonth []int       `json:"day_of_month"`
	DateSlice  []DateSlice `json:"date_slice"`
	//必选
	TimesOnDay  []string    `json:"times_on_day"`
	ExpandTags  []string    `json:"expand_tags"`
	ExpandValue interface{} `json:"expand_value"`
	Weights     float64     `json:"weights"`
}

type TimeArrows []TimeArrow

var GetData = func(group string) (TimeArrows, error) {
	return nil, errors.New("GetData 未实现")
}

func isInDateSlice(t time.Time, ta TimeArrow) bool {
	for e := range ta.DateSlice {
		startStr := ta.DateSlice[e].Start
		startSc := strings.Split(startStr, " ")
		if len(startSc) < 2 {
			startSc = append(startSc, "00:00:00")
		} else {
			startSc[1] = timeCompletion(startSc[1])
		}
		startStr = strings.Join(startSc, " ")

		endStr := ta.DateSlice[e].End
		endSc := strings.Split(endStr, " ")
		if len(endSc) < 2 {
			endSc = append(endSc, "00:00:00")
		} else {
			endSc[1] = timeCompletion(endSc[1])
		}
		endStr = strings.Join(endSc, " ")

		startTime, err := time.ParseInLocation("2006-01-02 15:04:05", startStr, time.Local)
		if err != nil {
			log.Println("时间段开始时间格式错误", startStr)
			continue
		}

		endTime, err := time.ParseInLocation("2006-01-02 15:04:05", endStr, time.Local)
		if err != nil {
			log.Println("时间段结束时间格式错误", startStr)
			continue
		}

		if startTime.Unix() > endTime.Unix() {
			log.Println("开始时间必须小于结束时间", startStr, endStr)
			continue
		}

		if (t.After(startTime) || t.Equal(startTime)) && t.Before(endTime) {
			return true
		}
	}
	return false
}

func isInWeekOfDay(t time.Time, ta TimeArrow) bool {
	nowWeekInt := int(t.Weekday())
	for k := range ta.DayOfWeek {
		if ta.DayOfWeek[k] == nowWeekInt {
			return true
		}
	}
	return false
}

func timeCompletion(a string) string {
	sc := strings.Split(a, ":")
	for len(sc) < 3 {
		sc = append(sc, "00")
	}
	return strings.Join(sc, ":")
}

func isInDayOfMonth(t time.Time, ta TimeArrow) bool {
	day := t.Day()
	for e := range ta.DayOfMonth {
		if ta.DayOfMonth[e] == day {
			return true
		}
	}
	return false
}

func isInTimeOfDay(t time.Time, ta TimeArrow) bool {
	if len(ta.TimesOnDay) == 0 {
		return true
	}
	for k := range ta.TimesOnDay {
		tsp := strings.Split(ta.TimesOnDay[k], "-")
		if len(tsp) < 2 {
			log.Println("必须为时间段:", ta.TimesOnDay[k])
			continue
		}

		start, end := tsp[0], tsp[1]
		start = timeCompletion(start)
		end = timeCompletion(end)
		startTime, err := time.ParseInLocation("2006-01-02 15:04:05", fmt.Sprintf("%s %s", t.Format("2006-01-02"), start), time.Local)
		if err != nil {
			log.Println("时间段开始时间格式错误", start)
			continue
		}
		endTime, err := time.ParseInLocation("2006-01-02 15:04:05", fmt.Sprintf("%s %s", t.Format("2006-01-02"), end), time.Local)
		if err != nil {
			log.Println("时间段结束时间格式错误", end)
			continue
		}

		if startTime.Unix() > endTime.Unix() {
			log.Println("开始时间必须小于结束时间", end)
			continue
		}

		if (t.After(startTime) || t.Equal(startTime)) && t.Before(endTime) {
			return true
		}
	}
	return false
}

func isInExpandTags(ta TimeArrow, expandTag string) bool {
	if len(ta.ExpandTags) == 0 {
		return true
	}
	for e := range ta.ExpandTags {
		if ta.ExpandTags[e] == expandTag {
			return true
		}
	}

	return false
}

func createUUID() string {
	uid := uuid.Must(uuid.NewUUID())
	return uid.String()
}

//CreateDayOfWeekTypePlan 创建一个每周计划
func CreateDayOfWeekTypePlan(group string, dayOfWeek []int, timesOnDay []string, expandValue interface{}, expandTags []string, weights float64) TimeArrow {
	return TimeArrow{
		TimeArrowId: createUUID(),
		Type:        TimeArrowTypeDayOfWeek,
		Group:       group,
		DayOfWeek:   dayOfWeek,
		TimesOnDay:  timesOnDay,
		ExpandValue: expandValue,
		ExpandTags:  expandTags,
		Weights:     weights,
	}
}

//CreateDayOfMonthTypePlan 创建一个每月计划
func CreateDayOfMonthTypePlan(group string, dayOfMonth []int, timesOnDay []string, expandValue interface{}, expandTags []string, weights float64) TimeArrow {
	return TimeArrow{
		TimeArrowId: createUUID(),
		Type:        TimeArrowTypeDayOfMonth,
		Group:       group,
		DayOfMonth:  dayOfMonth,
		TimesOnDay:  timesOnDay,
		ExpandValue: expandValue,
		ExpandTags:  expandTags,
		Weights:     weights,
	}
}

//CreateDateSliceTypePlan 创建一个时间段计划
func CreateDateSliceTypePlan(group string, dateSlice []DateSlice, timesOnDay []string, expandValue interface{}, expandTags []string, weights float64) TimeArrow {
	return TimeArrow{
		TimeArrowId: createUUID(),
		Type:        TimeArrowTypeDateSlice,
		Group:       group,
		DateSlice:   dateSlice,
		TimesOnDay:  timesOnDay,
		ExpandValue: expandValue,
		ExpandTags:  expandTags,
		Weights:     weights,
	}
}

func GetHitTimeArrow(t time.Time, group string, expandTags ...string) (*TimeArrow, error) {
	ta, err := GetData(group)
	if err != nil {
		return nil, err
	}
	sort.Slice(ta, func(i, j int) bool {
		return ta[i].Weights > ta[j].Weights
	})
	for e := range ta {
		//当天具体时间判断
		if !isInTimeOfDay(t, ta[e]) {
			continue
		}

		//扩展标签判断
		if !isInExpandTags(ta[e], strings.Join(expandTags, "-")) {
			continue
		}

		switch ta[e].Type {
		case TimeArrowTypeDayOfWeek:
			//一周中某一天是否判定
			if isInWeekOfDay(t, ta[e]) {
				return &ta[e], nil
			}
			break
		case TimeArrowTypeDayOfMonth:
			//一月中某一天是否判定
			if isInDayOfMonth(t, ta[e]) {
				return &ta[e], nil
			}
			break

		case TimeArrowTypeDateSlice:
			//一月中某一天是否判定
			if isInDateSlice(t, ta[e]) {
				return &ta[e], nil
			}
			break
		default:
			log.Println("类型错误:", ta[e].Type)
		}
	}
	return nil, nil
}