package discord

import (
	"errors"
	"fmt"

	"github.com/bwmarrin/discordgo"
)

// DiscordClient -
type DiscordClient struct {
	Session   *discordgo.Session
	ID        string
	connected bool
}

// Errors
var (
	ErrTokenEmpty   = errors.New("token is empty")
	ErrGuildIDEmpty = errors.New("guild id is empty")
)

var client *DiscordClient

// NewClient -
func NewClient(token string) (*DiscordClient, error) {
	if len(token) == 0 {
		return nil, ErrTokenEmpty
	}
	var err error

	client = &DiscordClient{}
	client.Session, err = discordgo.New(fmt.Sprintf("Bot %s", token))
	if err != nil {
		return nil, err
	}
	// register event
	client.Session.AddHandler(messageCreateEvt)
	client.Session.AddHandler(guildMemberAddEvt)
	client.Session.AddHandler(guildMemberRemoveEvt)
	client.Session.AddHandler(rateLimitEvt)
	client.Session.AddHandler(connectEvt)
	client.Session.AddHandler(disconnectEvt)

	botInfo, err := client.Session.User("@me")
	if err != nil {
		return client, err
	}
	client.ID = botInfo.ID

	return client, nil
}

// Connect to discord websocket
func (p *DiscordClient) Connect() error {
	if p.connected == true {
		return nil
	}
	return p.Session.Open()
}

// Close discord websocket connection
func (p *DiscordClient) Close() error {
	if p.connected == false {
		return nil
	}
	return p.Session.Close()
}

// GetGuildOwner -
func (p *DiscordClient) GetGuildOwner(guild string) (ownerID string, err error) {
	if len(ownerID) == 0 {
		return "", ErrGuildIDEmpty
	}
	guildInfo, err := p.Session.Guild(guild)
	if err != nil {
		return "", err
	}
	ownerID = guildInfo.OwnerID
	return
}

// GuildRole -
type GuildRole struct {
	Name string
	ID   string
}

// GetGuildRoles -
func (p *DiscordClient) GetGuildRoles(guild string) (roles []GuildRole, err error) {
	if len(guild) == 0 {
		return nil, ErrGuildIDEmpty
	}

	roleInfos, err := p.Session.GuildRoles(guild)
	if err != nil {
		return
	}

	roles = make([]GuildRole, 0, len(roleInfos))
	for _, role := range roleInfos {
		r := GuildRole{
			ID:   role.ID,
			Name: role.Name,
		}
		roles = append(roles, r)
	}

	return
}

// SendMessage -
func (p *DiscordClient) SendMessage() error {

	return nil
}