package bot

import (
	"context"
	"fmt"
	"strings"
	"time"

	"git.dev.m-and-m.ovh/mderasse/tesla/alert"
	"git.dev.m-and-m.ovh/mderasse/tesla/api"

	log "github.com/sirupsen/logrus"
	tele "gopkg.in/telebot.v3"
)

var apiClient *api.Client

// Init will initialize telegram bot.
func Init(alertChan chan api.Availability) {
	log.Info("Starting bot initialization")

	log.Debug("Loading bot configuration")
	config, err := initBotConfig()
	if err != nil {
		log.Fatalf("Fail to initialize bot configuration. Error: %s", err.Error())
	}

	apiClient, err = api.NewClient()
	if err != nil {
		log.Fatalf("Fail to instantiate the HTTP Client. Error: %s", err.Error())
	}

	pref := tele.Settings{
		Token:     config.Token,
		Poller:    &tele.LongPoller{Timeout: 10 * time.Second},
		ParseMode: tele.ModeMarkdownV2,
	}

	bot, err := tele.NewBot(pref)
	if err != nil {
		log.Fatal(err)
		return
	}

	log.Debug("Initializing bot middlewares")
	initMiddlewares(bot, config)

	log.Debug("Initializing bot commands")
	initCommands(bot, config)

	log.Debug("Launching alert handler")
	go handleAlert(bot, config, alertChan)

	bot.Start()
}

func handleAlert(bot *tele.Bot, config *botConfig, alertChan chan api.Availability) {
	for availability := range alertChan {

		for _, chatId := range config.AlertChatIds {
			log.Infof("Sending alert to chat %d", chatId)

			_, err := bot.Send(
				tele.ChatID(chatId),
				fmt.Sprintf(
					"ALERT\\!\\! Found a %s in *%s* color is: *%d*€ [View](%s)",
					availability.TrimName,
					strings.Join(availability.Paint, " and "),
					availability.Price,
					availability.GetOrderLink(),
				),
			)
			if err != nil {
				log.Warnf("Fail to send alert message. Error: %s", err.Error())
			}
		}
	}
}

func initMiddlewares(bot *tele.Bot, config *botConfig) {
	log.Infof("Trusting the following chats: %v", config.WhiteListChatIds)
	bot.Use(
		middlewareAllowChat(config.WhiteListChatIds...),
	)
}

func middlewareAllowChat(chatIds ...int64) tele.MiddlewareFunc {
	return func(next tele.HandlerFunc) tele.HandlerFunc {
		return func(c tele.Context) error {
			for _, chat := range chatIds {
				if chat == c.Chat().ID {
					return next(c)
				}
			}
			return nil
		}
	}
}

func initCommands(bot *tele.Bot, config *botConfig) {

	bot.Handle(tele.OnText, func(c tele.Context) error {

		msg := c.Text()
		if c.Chat().ID < 0 {
			if !strings.HasPrefix(msg, fmt.Sprintf("@%s", config.BotName)) {
				return nil
			}

			msg = strings.TrimPrefix(msg, fmt.Sprintf("@%s ", config.BotName))
		}

		log.Debugf("receive telegram message: %s", msg)

		switch strings.ToLower(msg) {
		case "help":
			return help(c)
		case "price":
			return price(c)
		case "list":
			return list(c)
		default:
			return home(c)
		}
	})

	bot.Handle(&tele.Btn{Unique: "list"}, list)
	bot.Handle(&tele.Btn{Unique: "price"}, price)
	bot.Handle(&tele.Btn{Unique: "help"}, help)
	bot.Handle(&tele.Btn{Unique: "home"}, home)
}

func home(c tele.Context) error {
	return c.EditOrReply(
		"Welcome to Tesla Alerter\\. What can i do for you ?",
		&homeMenu,
	)
}

func help(c tele.Context) error {
	return c.EditOrReply(
		fmt.Sprintf(`I'm a bot that have for main objective to inform you about tesla price\.
	I will also send you alert when tesla car are at a price under %d€`, alert.PriceAlert),
		&helpMenu,
	)
}

func price(c tele.Context) error {
	availabilities, err := apiClient.GetAvailabilities(context.Background(), &api.AvailabilityParams{
		Query: carFilter,
		Count: 100,
	})
	if err != nil {
		log.Warnf("Fail to retrieve availability from tesla website. Error: %s", err.Error())
		return c.Send("Fail to retrieve availability from tesla website :(")
	}

	var longRange api.Availability
	var propulsion api.Availability
	for _, availability := range availabilities.Results {
		if longRange.TrimName == "" && availability.Trim[0] == "LRAWD" {
			longRange = availability
		}
		if propulsion.TrimName == "" && availability.Trim[0] == "SRRWD" {
			propulsion = availability
		}
		if propulsion.TrimName != "" && longRange.TrimName != "" {
			break
		}
	}

	var msg string
	if propulsion.TrimName == "" {
		msg = "There is no Tesla Propulsion available\n"
	} else {
		msg = fmt.Sprintf("The lowest price currently found for a *%s* in *%s* color is: *%d*€ [View](%s)\n",
			propulsion.TrimName,
			strings.Join(propulsion.Paint, " and "),
			propulsion.Price,
			propulsion.GetOrderLink(),
		)
	}

	if longRange.TrimName == "" {
		msg = fmt.Sprintf("%sThere is no Tesla Long Range available", msg)
	} else {
		msg = fmt.Sprintf("%sThe lowest price currently found for a *%s* in *%s* color is: *%d*€ [View](%s)\n",
			msg,
			longRange.TrimName,
			strings.Join(longRange.Paint, " and "),
			longRange.Price,
			longRange.GetOrderLink(),
		)
	}

	return c.Reply(
		msg, &homeMenu,
	)
}

func list(c tele.Context) error {
	availabilities, err := apiClient.GetAvailabilities(context.Background(), &api.AvailabilityParams{
		Query: carFilter,
		Count: 30,
	})
	if err != nil {
		log.Warnf("Fail to retrieve availability from tesla website. Error: %s", err.Error())
		return c.Send("Fail to retrieve availability from tesla website :(")
	}

	availabilitiesStr := fmt.Sprintf("Found *%s* cars\n", availabilities.TotalMatchesFound)
	for _, availability := range availabilities.Results {
		availabilitiesStr = fmt.Sprintf(
			"%s%s, color *%s* available in *%s* for *%d*€ [View](%s)\n",
			availabilitiesStr,
			availability.TrimName,
			strings.Join(availability.Paint, " and "),
			strings.ReplaceAll(availability.City, "-", "\\-"),
			availability.Price,
			availability.GetOrderLink(),
		)
	}

	return c.Reply(availabilitiesStr, &homeMenu)
}