package main

import (
	"github.com/diamondburned/arikawa/discord"
	"github.com/diamondburned/arikawa/gateway"
	"github.com/diamondburned/arikawa/state"
	log "github.com/sirupsen/logrus"
	"github.com/spf13/viper"
	"os"
	"os/signal"
	"strings"
	"time"
)

var (
	s                 *state.State
	channels          []discord.ChannelID
	prohibitedPhrases []string
)

func setupConfiguration() {
	viper.SetDefault("prohibitedPhrases", "")
	viper.SetDefault("channels", "")
	viper.SetDefault("message", "Hi {username}, you've posted a message that was automatically removed for matching a filter. If you  need help, please use the correct channel.")

	viper.AutomaticEnv()

	viper.SetConfigName("ottomate")
	viper.SetConfigType("yaml")
	viper.AddConfigPath("/etc/ottomate/")
	viper.AddConfigPath("$HOME/.ottomate")
	viper.AddConfigPath(".")

	viper.ReadInConfig()
}

func main() {
	setupConfiguration()

	var token = viper.GetString("token")

	if token == "" {
		log.Fatalln("Invalid token/token is not set")
	}

	var channelStrs []string

	if viper.ConfigFileUsed() != "" {
		channelStrs = viper.GetStringSlice("channels")
	} else {
		channelStrs = strings.Split(viper.GetString("channels"), ",")
	}

	channels = make([]discord.ChannelID, len(channelStrs))

	for i, channelStr := range channelStrs {
		sf, err := discord.ParseSnowflake(channelStr)

		if err != nil {
			continue
		}

		channels[i] = discord.ChannelID(sf)
	}

	if viper.ConfigFileUsed() != "" {
		prohibitedPhrases = viper.GetStringSlice("phohibitedPhrases")
	} else {
		prohibitedPhrases = strings.Split(viper.GetString("prohibitedPhrases"), ",")
	}

	var err error

	s, err = state.New("Bot " + token)
	if err != nil {
		log.WithError(err).Fatalln("Session failed")
	}

	s.AddHandler(messageCreate)

	if err := s.Open(); err != nil {
		log.WithError(err).Fatalln("Failed to connect")
	}

	defer s.Close()

	u, err := s.Me()

	if err != nil {
		log.WithError(err).Fatalln("Failed to get myself")
	}

	log.WithField("username", u.Username).Info("Started bot")

	ch := make(chan os.Signal)
	signal.Notify(ch, os.Kill, os.Interrupt)
	<-ch
}

func messageCreate(e *gateway.MessageCreateEvent) {
	if e.Content == "" {
		return
	}

	found := false

	for _, channel := range channels {
		if channel == e.ChannelID {
			found = true
			break
		}
	}

	if !found {
		return
	}

	found = false

	for _, phrase := range prohibitedPhrases {
		if strings.Contains(e.Content, phrase) {
			// Send message
			found = true
			break
		}
	}

	if !found {
		return
	}

	member, err := s.Member(e.GuildID, e.Author.ID)

	if err != nil || !member.Joined.IsValid() {
		log.WithFields(log.Fields{
			"guildId": e.GuildID,
			"userId":  e.Author.ID,
		}).Debug("Unable to retrieve guild member")
		return
	}

	joinTime := member.Joined.Time()

	if joinTime.Before(time.Now().AddDate(0, 0, -7)) {
		log.WithFields(log.Fields{
			"guildId": e.GuildID,
			"userId":  e.Author.ID,
		}).Debug("Join date below cutoff")
		return
	}

	err = s.DeleteMessage(e.ChannelID, e.ID)

	if err != nil {
		log.WithFields(log.Fields{
			"guildId":   e.GuildID,
			"userId":    e.Author.ID,
			"messageId": e.ID,
		}).Debug("Unable to delete message")
		return
	}

	ch, err := s.CreatePrivateChannel(e.Author.ID)

	if err != nil {
		log.WithFields(log.Fields{
			"guildId": e.GuildID,
			"userId":  e.Author.ID,
		}).Debug("Unable to create private channel with member")
		return
	}

	message := viper.GetString("message")

	replacer := strings.NewReplacer("{username}", e.Author.Username, "{message}", e.Content)

	_, err = s.SendText(ch.ID, replacer.Replace(message))

	if err != nil {
		// Unable to send message
		log.WithFields(log.Fields{
			"guildId": e.GuildID,
			"userId":  e.Author.ID,
		}).Debug("Unable to send message in private channel")
	}
}