package core

import (
	"bytes"
	"fmt"
	"math/rand"
	"sort"
	"strings"
	"time"

	"github.com/bwmarrin/discordgo"
)

// This function will be called (due to AddHandler above) every time a new
// guild is joined.
func GuildCreate(s *discordgo.Session, event *discordgo.GuildCreate) {

	if event.Guild.Unavailable {
		return
	}

	for _, channel := range event.Guild.Channels {
		if channel.ID == event.Guild.ID {
			_, _ = s.ChannelMessageSend(channel.ID, "Airhorn is ready! Type !airhorn while in a voice channel to play a sound.")
			return
		}
	}
}

func getHelpMessage() string {
	// build list of possible commands
	// TODO: currently, the help needs to get value initiated at startup time to be built.
	// I don't like that and wish to test what is rendered without connecting to the server
	var help []string
	for _, command := range CommandRegister {
		help = append(help,
			fmt.Sprintf(
				"%s : %s (Example : %s)\n",
				command.name,
				command.desc,
				command.example))
	}
	sort.Strings(help)
	welcome := fmt.Sprintf(
		"Hello, I'm **%s**. Here are the things I can do :\n",
		ConfigRegister.Name)
	return welcome + strings.Join(help, "")
}

func getHatMessage() string {
	hat := []string{"🧢", "👒", "⛑", "🎩", "🎓"}
	rand.Seed(time.Now().UnixNano())
	var amount int = (rand.Intn(len(hat) -1) +1)
	var bag []string
	for i := 0; i < amount; i++ {
		rand.Seed(time.Now().UnixNano())
		bag = append(bag, hat[(rand.Intn(len(hat) -1) +1)])
	}
	return strings.Join(bag, " ")
}

func getTalkbackMessage(message string) string {
	for _, t := range ConfigRegister.Talkback {
		for _, p := range t.Domain.Patterns {
			rand.Seed(time.Now().UnixNano())
			if strings.Contains(strings.ToLower(message), strings.ToLower(p)) {
				rand.Seed(time.Now().UnixNano())
				return t.Domain.Answers[rand.Intn(len(t.Domain.Answers))]
			}
		}
	}
	return ""
}

func MessageHandler(s *discordgo.Session, m *discordgo.MessageCreate) {
	for alias, _ := range CommandRegister {
		if strings.HasPrefix(m.Content, alias) {
			if m.Author.ID == s.State.User.ID {
				return
			}
			var message string = strings.TrimPrefix(m.Content, alias)
			CommandRegister[alias].command(s, m, message)

		}
	}
}

func MessageHat(s *discordgo.Session, m *discordgo.MessageCreate, message string) {
	s.ChannelMessageSend(m.ChannelID, getHatMessage())
}

func MessageTalkback(s *discordgo.Session, m *discordgo.MessageCreate) {
	if m.Author.ID == s.State.User.ID {
		return
	}
	var answer string = getTalkbackMessage(m.Content)
	if answer != "" && rand.Intn(2) == 1 {
		s.ChannelMessageSend(m.ChannelID, answer)
	}
}

func MessageHelp(s *discordgo.Session, m *discordgo.MessageCreate, message string) {
	s.ChannelMessageSend(m.ChannelID, getHelpMessage())
}

func MessagePing(s *discordgo.Session, m *discordgo.MessageCreate, message string) {
	if m.Content == "ping" {
		s.ChannelMessageSend(m.ChannelID, "Pong!")
	}

	if m.Content == "pong" {
		s.ChannelMessageSend(m.ChannelID, "Ping!")
	}
}

func MessageAudio(s *discordgo.Session, m *discordgo.MessageCreate, message string) {
	var cleanMessage string = prepareTTSMessage(message)
	filename, out := getAudioMessage(cleanMessage)
	file := bytes.NewReader(out)
	s.ChannelFileSend(m.ChannelID, filename, file)
	// delete the receveid command after processing it. less clutter
	s.ChannelMessageDelete(m.ChannelID, m.ID)
}

func MessageVocal(s *discordgo.Session, m *discordgo.MessageCreate, message string) {
	// Ignore all messages created by the bot itself
	// This isn't required in this specific example but it's a good practice.
	if m.Author.ID == s.State.User.ID {
		return
	}

	// Find the channel that the message came from.
	c, err := s.State.Channel(m.ChannelID)
	if err != nil {
		// Could not find channel.
		return
	}
	
	// Find the guild for that channel.
	g, err := s.State.Guild(c.GuildID)
	if err != nil {
		// Could not find guild.
		return
	}

	var cleanMessage string = prepareTTSMessage(message)
	_, out := getAudioMessage(cleanMessage)

	// Look for the message sender in that guild's current voice states.
	for _, vs := range g.VoiceStates {
		if vs.UserID == m.Author.ID {
			err = playSound(s, g.ID, vs.ChannelID, out)
			if err != nil {
				fmt.Println("Error playing sound:", err)
			}	
			return
		}
	}
}