// Countdown is a plugin to do tasks on various milestones.
package countdown

import (
	"fmt"
	bh "github.com/timshannon/bolthold"
	"github.com/velour/catbase/plugins/babbler"
	"github.com/velour/catbase/plugins/counter"
	"time"

	"github.com/rs/zerolog/log"

	"github.com/velour/catbase/bot"
	"github.com/velour/catbase/config"
)

var nextYear = time.Date(time.Now().Year()+1, time.January, 1, 0, 0, 0, 1, time.Local)
var thisYear = time.Now().Year()

type CountdownPlugin struct {
	b     bot.Bot
	store *bh.Store
	c     *config.Config
}

func New(b bot.Bot) *CountdownPlugin {
	p := &CountdownPlugin{
		b:     b,
		store: b.Store(),
		c:     b.Config(),
	}

	p.scheduleNYE(p.newYearRollover)

	return p
}

func (p *CountdownPlugin) scheduleNYE(f func()) {
	time.AfterFunc(nextYear.Sub(time.Now()), f)
	for i := 10; i > 0; i-- {
		mkFunc := func(i int) func() {
			return func() {
				p.nyeCountdown(i)
			}
		}
		time.AfterFunc(nextYear.Add(time.Duration(10-i)*time.Second).Sub(time.Now()), mkFunc(i))
	}
}

func (p *CountdownPlugin) newYearRollover() {
	log.Debug().Msgf("Happy new year!")

	if err := p.clearBabblers(); err != nil {
		log.Error().Err(err).Msgf("error clearing babblers")
	}

	if err := p.archiveCounters(); err != nil {
		log.Error().Err(err).Msgf("error clearing babblers")
	}
}

func (p *CountdownPlugin) nyeCountdown(i int) {
	chs := p.c.GetArray("channels", []string{})
	for _, ch := range chs {
		msg := fmt.Sprintf("%d!", i)
		p.b.Send(p.b.DefaultConnector(), bot.Message, ch, msg, msg)
	}
}

func (p *CountdownPlugin) clearBabblers() error {
	if err := p.store.DeleteMatching(babbler.Babbler{}, &bh.Query{}); err != nil {
		return err
	}
	if err := p.store.DeleteMatching(babbler.BabblerArc{}, &bh.Query{}); err != nil {
		return err
	}
	if err := p.store.DeleteMatching(babbler.BabblerNode{}, &bh.Query{}); err != nil {
		return err
	}
	if err := p.store.DeleteMatching(babbler.BabblerWord{}, &bh.Query{}); err != nil {
		return err
	}
	return nil
}

type counterArchive struct {
	counter.Item
	Year int
}

func (ca counterArchive) Key() string {
	return fmt.Sprintf("%d-%d", ca.Year, ca.ID)
}

func (p *CountdownPlugin) archiveCounters() error {
	year := time.Now().Year()
	allCounters := []counter.Item{}

	if err := p.store.Find(&allCounters, &bh.Query{}); err != nil {
		return err
	}
	for _, c := range allCounters {
		ca := counterArchive{c, year}
		err := p.store.Insert(ca.Key(), ca)
		if err != nil {
			return err
		}
	}

	if err := p.store.DeleteMatching(counter.Item{}, &bh.Query{}); err != nil {
		return err
	}

	return nil
}