package main

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

	"github.com/bwmarrin/discordgo"
	"github.com/joho/godotenv"
)

var (
	token       string
	reactUserID string
)

func init() {
	err := godotenv.Load()

	if err != nil {
		fmt.Println("Could not load .env file: ", err)
		os.Exit(1)
	}

	token = os.Getenv("DISCORD_BOT_TOKEN")
	reactUserID = os.Getenv("REACT_USER_ID")

	if token == "" || reactUserID == "" {
		fmt.Println("DISCORD_BOT_TOKEN and REACT_USER_ID variables have to be set.")
		os.Exit(1)
	}
}

func main() {
	bot, err := discordgo.New("Bot " + token)

	if err != nil {
		fmt.Println("Could not create Discord bot instance:", err)
		return
	}

	bot.AddHandler(messageCreate)

	err = bot.Open()
	if err != nil {
		fmt.Println("Error opening connection to Discord:", err)
		return
	}

	fmt.Println("Bot is now running.  Press CTRL-C to exit.")
	sc := make(chan os.Signal, 1)
	signal.Notify(sc, syscall.SIGINT, syscall.SIGTERM, os.Interrupt, os.Kill)
	<-sc

	bot.Close()
}

func messageCreate(sess *discordgo.Session, msg *discordgo.MessageCreate) {
	if msg.Author.ID != reactUserID {
		return
	}

	channelID := msg.ChannelID
	msgID := msg.ID

	err := sess.MessageReactionAdd(channelID, msgID, "🗿")

	if err != nil {
		fmt.Println("Error occurred reacting to message ID: "+msgID, err)
	}
}