package main

import (
	"flag"
	"fmt"
	"github.com/gorcon/rcon"
	"log"
	"os"
	"os/signal"
	"slices"
	"syscall"

	"github.com/bwmarrin/discordgo"
)

// Variables used for command line parameters
var (
	Token        string
	MemberRole   string
	GuildID      string
	RCONServer   string
	RCONPassword string
)

// Command vairables
var (
	commands = []*discordgo.ApplicationCommand{
		{
			Name:        "welcome",
			Description: "Welcome a new member to the Server, giving them full membership permission.",
			Options: []*discordgo.ApplicationCommandOption{
				{
					Name:        "user",
					Description: "User to welcome as a new member.",
					Type:        discordgo.ApplicationCommandOptionUser,
					Required:    true,
				},
			},
		},
		{
			Name:        "whitelist",
			Description: "Whitelist a user on the minecraft server.",
			Options: []*discordgo.ApplicationCommandOption{
				{
					Name:        "username",
					Description: "Username to whitelist",
					Type:        discordgo.ApplicationCommandOptionString,
					Required:    true,
				},
				{
					Name:        "bedrock",
					Description: "Is this a bedrock user?",
					Type:        discordgo.ApplicationCommandOptionBoolean,
					Required:    false,
				},
			},
		},
	}

	commandHandlers = map[string]func(s *discordgo.Session, i *discordgo.InteractionCreate){
		"welcome": func(s *discordgo.Session, i *discordgo.InteractionCreate) {
			caller, _ := s.GuildMember(i.GuildID, i.Member.User.ID)

			// check if the user is a member
			if !slices.Contains(caller.Roles, MemberRole) {
				s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
					Type: discordgo.InteractionResponseChannelMessageWithSource,
					Data: &discordgo.InteractionResponseData{
						Content: "Only Members are allowed to run this command",
					},
				})
				return
			}

			options := i.ApplicationCommandData().Options
			new := options[0].UserValue(s)

			s.GuildMemberRoleAdd(i.GuildID, new.ID, MemberRole)

			s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
				Type: discordgo.InteractionResponseChannelMessageWithSource,
				Data: &discordgo.InteractionResponseData{
					Content: fmt.Sprintf("Welcome %s, you are now a member!", new.Mention()),
				},
			})
		},

		"whitelist": func(s *discordgo.Session, i *discordgo.InteractionCreate) {
			caller, err := s.GuildMember(i.GuildID, i.Member.User.ID)

			// check if the user is a member
			if !slices.Contains(caller.Roles, MemberRole) {
				s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
					Type: discordgo.InteractionResponseChannelMessageWithSource,
					Data: &discordgo.InteractionResponseData{
						Content: "Only Members are allowed to run this command",
					},
				})
				return
			}

			opts := i.ApplicationCommandData().Options
			name := opts[0].StringValue()
			bedrock := false
			if len(opts) > 1 {
				bedrock = opts[1].BoolValue()
			}

			con, err := rcon.Dial(RCONServer, RCONPassword)
			if err != nil {
				log.Printf("Could not connect to RCON server")
				s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
					Type: discordgo.InteractionResponseChannelMessageWithSource,
					Data: &discordgo.InteractionResponseData{
						Content: "Failed to whitelist, server may be down?",
					},
				})
				return
			}

			err = nil

			if bedrock {
				_, err = con.Execute(fmt.Sprintf("fwhitelist add %s", name))
			} else {
				_, err = con.Execute(fmt.Sprintf("whitelist add %s", name))
			}

			con.Close()

			if err != nil {
				s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
					Type: discordgo.InteractionResponseChannelMessageWithSource,
					Data: &discordgo.InteractionResponseData{
						Content: "Ups! Something went wrong!",
					},
				})
				return
			}

			log.Printf("Whitelisted %s, on behalf of %s.", name, i.Member.User.ID)

			s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
				Type: discordgo.InteractionResponseChannelMessageWithSource,
				Data: &discordgo.InteractionResponseData{
					Content: fmt.Sprintf("`%s` should now be whitelisted!", name),
				},
			})
		},
	}
)

// parse CLI arguments
func init() {
	flag.StringVar(&Token, "t", "", "Bot Token")
	flag.StringVar(&MemberRole, "r", "", "ID of the member role")
	flag.StringVar(&GuildID, "g", "", "Id of the Guild")
	flag.StringVar(&RCONServer, "rs", "", "RCON server to connect to")
	flag.StringVar(&RCONPassword, "rp", "", "Password for the RCON server")

	flag.Parse()
}

func main() {
	bot, err := discordgo.New("Bot " + Token)
	if err != nil {
		log.Panicf("Could not create bot!")
	}

	bot.AddHandler(func(s *discordgo.Session, i *discordgo.InteractionCreate) {
		if h, ok := commandHandlers[i.ApplicationCommandData().Name]; ok {
			h(s, i)
		}
	})

	// Open a websocket connection to Discord and begin listening.
	err = bot.Open()
	if err != nil {
		log.Panicf("Error connecting to discord: %s", err)
		return
	}

	log.Println("Adding commands...")
	registeredCommands := make([]*discordgo.ApplicationCommand, len(commands))
	for i, v := range commands {
		cmd, err := bot.ApplicationCommandCreate(bot.State.User.ID, GuildID, v)
		if err != nil {
			log.Panicf("Cannot create '%v' command: %v", v.Name, err)
		}
		registeredCommands[i] = cmd
	}

	log.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)
	<-sc

	log.Println("Exiting")
	err = bot.Close()
	if err != nil {
		log.Printf("Failed to shut down gracefully! %s", err)
	}
}