package discord

import (
	"fmt"
	"os"
	"os/signal"
	"sync"
	"syscall"

	"git.mgmcomp.net/thisnthat/discord-bot/bot/event/mux"
	"github.com/bwmarrin/discordgo"
	"github.com/sirupsen/logrus"
)

type Bot struct {
	token       string
	session     *discordgo.Session
	online      bool
	running     chan os.Signal
	slashRouter *mux.SlashRouter
}

func (bot *Bot) AddHandler(handler interface{}) error {
	// If the bot is online, we can not add a handler
	if bot.online {
		err := fmt.Errorf("unable to add handler to a bot that is already online")
		return err
	}

	bot.session.AddHandler(handler)
	return nil
}

func (bot *Bot) SetEventRouter(router *mux.Router) {
	bot.AddHandler(router.OnMessageCreate)
}

func (bot *Bot) SetSlashEventRouter(slashRouter *mux.SlashRouter) {
	bot.slashRouter = slashRouter
}

func (bot *Bot) Start(wg *sync.WaitGroup) error {
	defer wg.Done()

	err := bot.session.Open()
	if err != nil {
		return err
	}

	err = bot.slashRouter.GenerateCommands(bot.session)
	if err != nil {
		return err
	}

	go logrus.Info("The bot has started")
	bot.running = make(chan os.Signal, 1)
	bot.online = true
	signal.Notify(bot.running, syscall.SIGINT, syscall.SIGTERM)
	<-bot.running

	bot.slashRouter.CleanCommands(bot.session)
	bot.session.Close()
	go logrus.Info("The bot has gone offline")
	bot.online = false

	return nil
}

func (bot *Bot) Stop() {
	if bot.online {
		bot.running <- syscall.SIGINT
	}
}

func NewBot(token string) (*Bot, error) {
	bot := &Bot{}
	bot.token = token

	var err error
	bot.session, err = discordgo.New("Bot " + bot.token)

	if err != nil {
		return bot, err
	}

	return bot, nil
}