package startimer

import (
	"context"
	"sync"
	"time"
)

type Unit uint8

const (
	STAR_SECOND Unit = iota
	STAR_MINUTE
	STAR_HOUR
	STAR_DAY
	STAR_MONTH
	STAR_WEEK
	STAR_YEAR
)

type Repeats struct {
	Repeat []Repeat `json:"repeat"`
	Every  bool     `json:"every"` // false=static true=every
}

type Repeat struct {
	Unit     Unit `json:"unit"`
	baseDate time.Time
	Value    uint32 `json:"value"`
}

type StarTimer struct {
	base     time.Time
	nextDate time.Time
	timer    *time.Timer
	stopFn   context.CancelFunc
	stopCtx  context.Context
	mu       *sync.RWMutex
	running  bool
	repeat   []*Repeats
	tasks    []func()
}

type TimerOptions func(option *TimerOption)

type TimerOption struct {
	idx     uint8
	repeats *Repeats
	tasks   func()
	date    time.Time
	repeat  Repeat
}

func WithRepeats(r *Repeats) TimerOptions {
	return func(option *TimerOption) {
		option.idx = 1
		option.repeats = r
	}
}

func WithRepeat(r Repeat) TimerOptions {
	return func(option *TimerOption) {
		option.idx = 4
		option.repeat = r
	}
}

func WithTask(t func()) TimerOptions {
	return func(option *TimerOption) {
		option.idx = 2
		option.tasks = t
	}
}

func WithStaticDate(t time.Time) TimerOptions {
	return func(option *TimerOption) {
		option.idx = 3
		option.date = t
	}
}

func NewRepeat(baseTime time.Time, unit Unit, val uint32) Repeat {
	return Repeat{
		Unit:     unit,
		baseDate: baseTime,
		Value:    val,
	}
}

func NextDayOfWeek(date time.Time, weekDay int) time.Time {
	sub := weekDay - int(date.Weekday())
	if sub <= 0 {
		sub += 7
	}
	return date.Add(time.Hour * 24 * time.Duration(sub))
}