package alerts

import (
	"sync"
	"text/template"

	"git.sr.ht/~ashkeel/strimertul/twitch/eventsub"

	template2 "git.sr.ht/~ashkeel/strimertul/twitch/template"

	jsoniter "github.com/json-iterator/go"
	"go.uber.org/zap"

	"git.sr.ht/~ashkeel/strimertul/database"
)

var json = jsoniter.ConfigFastest

type (
	templateCache    map[string]*template.Template
	templateCacheMap map[templateType]templateCache
)

type templateType string

const (
	templateTypeSubscription templateType = "subscription"
	templateTypeFollow       templateType = "follow"
	templateTypeRaid         templateType = "raid"
	templateTypeCheer        templateType = "cheer"
	templateTypeGift         templateType = "gift"
)

type Module struct {
	Config Config

	db        database.Database
	logger    *zap.Logger
	templater template2.Engine
	templates templateCacheMap

	cancelAlertSub       database.CancelFunc
	cancelTwitchEventSub database.CancelFunc

	pendingMux  sync.Mutex
	pendingSubs map[string]subMixedEvent
}

func Setup(db database.Database, logger *zap.Logger, templater template2.Engine) *Module {
	mod := &Module{
		db:          db,
		logger:      logger,
		templater:   templater,
		pendingMux:  sync.Mutex{},
		pendingSubs: make(map[string]subMixedEvent),
	}

	// Load config from database
	err := db.GetJSON(ConfigKey, &mod.Config)
	if err != nil {
		logger.Debug("Config load error", zap.Error(err))
		mod.Config = Config{}
		// Save empty config
		err = db.PutJSON(ConfigKey, mod.Config)
		if err != nil {
			logger.Warn("Could not save default config for bot alerts", zap.Error(err))
		}
	}

	mod.compileTemplates()

	mod.cancelAlertSub, err = db.SubscribeKey(ConfigKey, func(value string) {
		err := json.UnmarshalFromString(value, &mod.Config)
		if err != nil {
			logger.Warn("Error loading alert config", zap.Error(err))
		} else {
			logger.Info("Reloaded alert config")
		}
		mod.compileTemplates()
	})
	if err != nil {
		logger.Error("Could not set-up bot alert reload subscription", zap.Error(err))
	}

	mod.cancelTwitchEventSub, err = db.SubscribePrefix(mod.onEventSubEvent, eventsub.EventKeyPrefix)
	if err != nil {
		logger.Error("Could not setup twitch alert subscription", zap.Error(err))
	}

	logger.Debug("Loaded bot alerts")

	return mod
}

func (m *Module) Close() {
	if m.cancelAlertSub != nil {
		m.cancelAlertSub()
	}
	if m.cancelTwitchEventSub != nil {
		m.cancelTwitchEventSub()
	}
}