package irc

import (
	"time"
	"os"
	"strings"
	"fmt"

	. "git.deuxfleurs.fr/Deuxfleurs/easybridge/connector"

	"github.com/lrstanley/girc"
)

// User id format: nickname@server

// Room id format: #room_name@server

type IRC struct {
	handler Handler

	connected bool
	timeout int

	nick string
	name string
	server string
	conn *girc.Client
}

func (irc *IRC) SetHandler(h Handler) {
	irc.handler = h
}

func(irc *IRC) Protocol() string {
	return "irc"
}

func (irc *IRC) Configure(c Configuration) error {
	if irc.conn != nil {
		irc.Close()
	}

	var err error

	irc.nick, err = c.GetString("nick")
	if err != nil {
		return err
	}

	irc.server, err = c.GetString("server")
	if err != nil {
		return err
	}

	port, err := c.GetInt("port", 6666)
	if err != nil {
		return err
	}

	ssl, err := c.GetBool("ssl", true)
	if err != nil {
		return err
	}

	client := girc.New(girc.Config{
		Server: irc.server,
		Port: port,
		Nick: irc.nick,
		User: irc.nick,
		Out: os.Stderr,
		SSL: ssl,
	})

	client.Handlers.Add(girc.CONNECTED, irc.ircConnected)
	//client.Handlers.Add(girc.DISCONNECTED, irc.ircDisconnected)
	//client.Handlers.Add(girc.NICK, irc.ircNick)
	client.Handlers.Add(girc.PRIVMSG, irc.ircPrivmsg)
	client.Handlers.Add(girc.JOIN, irc.ircJoin)
	client.Handlers.Add(girc.PART, irc.ircPart)
	client.Handlers.Add(girc.RPL_NAMREPLY, irc.ircNamreply)
	client.Handlers.Add(girc.RPL_TOPIC, irc.ircTopic)

	irc.conn = client
	go irc.connectLoop(client)

	for i := 0; i < 42; i++ {
		time.Sleep(time.Duration(1)*time.Second)
		if irc.conn != client {
			break
		}
		if irc.connected {
			return nil
		}
	}
	return fmt.Errorf("Failed to connect after 42s attempting")
}

func (irc *IRC) User() UserID {
	return UserID(irc.nick + "@" + irc.server)
}

func (irc *IRC) checkRoomId(id RoomID) (string, error) {
	x := strings.Split(string(id), "@")
	if len(x) != 2 || x[1] != irc.server || x[0][0] != '#' {
		return "", fmt.Errorf("Invalid room ID: %s", id)
	}
	return x[0], nil
}

func (irc *IRC) checkUserId(id UserID) (string, error) {
	x := strings.Split(string(id), "@")
	if len(x) != 2 || x[1] != irc.server || x[0][0] == '#' {
		return "", fmt.Errorf("Invalid user ID: %s", id)
	}
	return x[0], nil
}

func (irc *IRC) SetUserInfo(info *UserInfo) error {
	return fmt.Errorf("Not implemented")
}

func (irc *IRC) SetRoomInfo(roomId RoomID, info *RoomInfo) error {
	ch, err := irc.checkRoomId(roomId)
	if err != nil {
		return err
	}

	if info.Name != "" && info.Name != ch {
		return fmt.Errorf("May not change IRC room name to other than %s", ch)
	}
	if info.Picture != nil {
		return fmt.Errorf("Room picture not supported on IRC")
	}
	irc.conn.Cmd.Topic(ch, info.Description)
	return nil
}

func (irc *IRC) Join(roomId RoomID) error {
	ch, err := irc.checkRoomId(roomId)
	if err != nil {
		return err
	}

	irc.conn.Cmd.Join(ch)
	return nil
}

func (irc *IRC) Invite(userId UserID, roomId RoomID) error {
	ch, err := irc.checkRoomId(roomId)
	if err != nil {
		return err
	}

	who, err := irc.checkUserId(userId)
	if err != nil {
		return err
	}

	irc.conn.Cmd.Invite(ch, who)
	return nil
}

func (irc *IRC) Leave(roomId RoomID) {
	ch, err := irc.checkRoomId(roomId)
	if err != nil {
		return
	}

	irc.conn.Cmd.Part(ch)
}

func (irc *IRC) Send(event *Event) error {
	dest := ""
	if event.Room != "" {
		ch, err := irc.checkRoomId(event.Room)
		if err != nil {
			return err
		}
		dest = ch
	} else if event.Recipient != "" {
		ui, err := irc.checkUserId(event.Recipient)
		if err != nil {
			return err
		}
		dest = ui
	} else {
		return fmt.Errorf("Invalid target")
	}

	if event.Attachements != nil && len(event.Attachements) > 0 {
		// TODO find a way to send them using some hosing of some kind
		return fmt.Errorf("Attachements not supported on IRC")
	}

	if event.Type == EVENT_MESSAGE {
		irc.conn.Cmd.Message(dest, event.Text)
	} else if event.Type == EVENT_ACTION {
		irc.conn.Cmd.Action(dest, event.Text)
	} else {
		return fmt.Errorf("Invalid event type")
	}
	return nil
}

func (irc *IRC) Close() {
	conn := irc.conn
	irc.conn = nil
	conn.Close()
}

func (irc *IRC) connectLoop(c *girc.Client) {
	irc.timeout = 10
	for {
		if irc.conn != c {
			return
		}
		if err := c.Connect(); err != nil {
			irc.connected = false
			fmt.Printf("IRC failed to connect / disconnected: %s\n", err)
			fmt.Printf("Retrying in %ds\n", irc.timeout)
			time.Sleep(time.Duration(irc.timeout) * time.Second)
			irc.timeout *= 2
			if irc.timeout > 600 {
				irc.timeout = 600
			}
		} else {
			return
		}
	}
}

func (irc *IRC) ircConnected(c *girc.Client, e girc.Event) {
	fmt.Printf("ircConnected ^^^^\n")
	irc.timeout = 10
	irc.connected = true
}

func (irc *IRC) ircPrivmsg(c *girc.Client, e girc.Event) {
	ev := &Event{
		Type: EVENT_MESSAGE,
		Author: UserID(e.Source.Name + "@" + irc.server),
		Text: e.Last(),
	}
	if e.IsFromChannel() {
		ev.Room = RoomID(e.Params[0] + "@" + irc.server)
	}
	if e.IsAction() {
		ev.Type = EVENT_ACTION
	}
	irc.handler.Event(ev)
}

func (irc *IRC) ircJoin(c *girc.Client, e girc.Event) {
	room := RoomID(e.Params[0] + "@" + irc.server)
	if e.Source.Name == irc.nick {
		irc.handler.Joined(room)
	} else {
		ev := &Event{
			Type: EVENT_JOIN,
			Author: UserID(e.Source.Name + "@" + irc.server),
			Room: room,
		}
		irc.handler.Event(ev)
	}
}

func (irc *IRC) ircPart(c *girc.Client, e girc.Event) {
	room := RoomID(e.Params[0] + "@" + irc.server)
	if e.Source.Name == irc.nick {
		irc.handler.Left(room)
	} else {
		ev := &Event{
			Type: EVENT_LEAVE,
			Author: UserID(e.Source.Name + "@" + irc.server),
			Room: room,
		}
		irc.handler.Event(ev)
	}
}

func (irc *IRC) ircNamreply(c *girc.Client, e girc.Event) {
	room := RoomID(e.Params[2] + "@" + irc.server)
	names := strings.Split(e.Last(), " ")
	for _, name := range names {
		if name[0] == '@' {
			name = name[1:]
		}
		src := girc.ParseSource(name)
		if src.Name != irc.nick {
			irc.handler.Event(&Event{
				Type: EVENT_JOIN,
				Author: UserID(src.Name + "@" + irc.server),
				Room: room,
			})
		}
	}
}

func (irc *IRC) ircTopic(c *girc.Client, e girc.Event) {
	room := RoomID(e.Params[1] + "@" + irc.server)
	topic := e.Last()
	irc.handler.RoomInfoUpdated(room, &RoomInfo{
		Name: string(room),
		Description: topic,
	})
}