package main

import (
	"log"
	"fmt"
	"net"
	"time"
	"bufio"
	"strings"
	"database/sql"
	configo "github.com/distributedio/configo"
	_ "github.com/mattn/go-sqlite3"
)

func sendmsg (conn net.Conn, channel string, msg string) {
	mesg := fmt.Sprintf("PRIVMSG %s :%s\r\n", channel, msg)
	fmt.Printf(mesg)
	conn.Write([]byte(mesg))
}

func scanline_privmsg (msg string, irc *irc_msg) {
	LOG_ERR.Printf(msg)

	msg = msg[1:]
	t := strings.Split(msg, "!")
	(*irc).author, (*irc).channel = t[0], t[1]
	t = strings.Split((*irc).channel, "PRIVMSG ")
	(*irc).channel = t[1]
	t = strings.Split((*irc).channel, " :")
	(*irc).channel, (*irc).msg = t[0], t[1]
	t = strings.Split((*irc).msg, "\r\n")
	(*irc).msg = strings.TrimSpace(t[0])
	if ! strings.HasPrefix((*irc).channel, "#") {
		(*irc).channel = (*irc).author
	}
	(*irc).retmsg = ""
}

func bot_connect(bot *bot) {
	conn, err := net.Dial("tcp", (*bot).Conf.Server)
	if err != nil {
		LOG_ERR.Printf("Error while dialing server.")
		(*bot).conn = nil
		return
	}

	(*bot).conn = conn
	fmt.Fprintf((*bot).conn, "USER %s 1 1 1:%s\r\n", (*bot).Conf.Name, (*bot).Conf.Name)
}

func bot_register(bot *bot) {
	/* connect to irc */
	fmt.Fprintf((*bot).conn, "NICK %s\r\n", (*bot).Conf.Name)
	for _, channel := range((*bot).Conf.Channels) {
		fmt.Fprintf((*bot).conn, "JOIN %s\r\n", channel)
	}
}

func bot_listen(bot *bot) <-chan string {
	c := make(chan string)
	bot_register(bot)

	go func(timeoutNormal time.Duration, timeoutVersion time.Duration) {
		bufReader := bufio.NewReader((*bot).conn)

		timeoutDuration := timeoutNormal
		waitversion := false

		defer func() {
			fmt.Println("Closing connection...")
			close(c)
			(*bot).conn.Close()
		}()

		for {
			(*bot).conn.SetReadDeadline(time.Now().Add(timeoutDuration))

			line, err := bufReader.ReadString('\n')
			if err != nil {
				if nerr, ok := err.(net.Error); ok && nerr.Timeout() {
					fmt.Printf("Timeout!\n")
					if waitversion {
						fmt.Println("VERSION command did not return.")
						return
					}

					n, err := (*bot).conn.Write([]byte("VERSION\n"))
					fmt.Printf("n: %d, err: %s\n", n, err)
					if err != nil {
						fmt.Println("Writing to channel failed.")
						return
					}
					// wait for return value of VERSION
					waitversion = true
					timeoutDuration = timeoutVersion
				} else {
					fmt.Println("Some more serious error occured while reading.")
					return
				}
				continue
			}

			// not waiting for version answer right now
			timeoutDuration = timeoutNormal
			waitversion = false
			c <- line

			if strings.Contains(line, "PING") {
				(*bot).conn.Write([]byte(strings.Replace(line, "PING", "PONG", 1)))
			} else if strings.Contains(line, "You have not registered") {
				// set nickname
				time.Sleep(10 * time.Second)
				bot_register(bot)
			} else if strings.Contains(line, "PRIVMSG") {
				var msg irc_msg
				scanline_privmsg(line, &msg)
				LOG_ERR.Printf(msg.author)
				parsemsg(&msg, (*bot))
				if msg.retmsg != "" {
					sendmsg((*bot).conn, msg.channel, msg.retmsg)
				}
			}
		}
	} (4 * time.Minute, 1 * time.Minute)

	return c
}

func bot_run(bot *bot) {
	LOG_INFO.Println("Bot ready to run.")

	LOG_INFO.Println("Opening database.")
	db, err = sql.Open("sqlite3", (*bot).Conf.Database)
	if err != nil {
		LOG_ERR.Println("Opening database failed.")
		return
	}

	for {
		bot_connect(bot)
		if bot.conn == nil {
			LOG_INFO.Printf("Bot is nil. Try to connect again.")
			time.Sleep(10 * time.Second)
			continue
		}
		for val := range bot_listen(bot) {
			LOG_INFO.Printf("%s", val)
		}
	}
}

func main() {
	LOG_init()

	var boddle bot
	if err := configo.Load("./boddle.toml", &boddle.Conf); err != nil {
		log.Fatal(err)
	}

	bot_run(&boddle)
}