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mirror of https://github.com/ergochat/ergo.git synced 2024-11-22 03:49:27 +01:00

massive refactor and basic channel support: join, part, message

This commit is contained in:
Jeremy Latt 2012-12-08 22:54:58 -08:00
parent 8ac1909c19
commit 24ad2172a8
10 changed files with 657 additions and 191 deletions

94
src/irc/channel.go Normal file
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@ -0,0 +1,94 @@
package irc
type Channel struct {
name string
key string
topic string
members ClientSet
inviteOnly bool
invites map[string]bool
server *Server
}
type ChannelSet map[*Channel]bool
func NewChannel(s *Server, name string) *Channel {
return &Channel{name: name, members: make(ClientSet), invites: make(map[string]bool), server: s}
}
func (ch *Channel) Send(reply Reply, fromClient *Client) {
for client := range ch.members {
if client != fromClient {
client.send <- reply
}
}
}
// channel functionality
func (ch *Channel) Join(cl *Client, key string) {
if ch.key != key {
cl.send <- ErrInviteOnlyChannel(ch)
return
}
if ch.inviteOnly && !ch.invites[cl.nick] {
cl.send <- ErrBadChannelKey(ch)
return
}
ch.members[cl] = true
cl.channels[ch] = true
ch.Send(RplJoin(ch, cl), nil)
ch.GetTopic(cl)
for member := range ch.members {
cl.send <- RplNamReply(ch, member)
}
cl.send <- RplEndOfNames(ch.server)
}
func (ch *Channel) Part(cl *Client, message string) {
if !ch.members[cl] {
cl.send <- ErrNotOnChannel(ch)
return
}
delete(ch.members, cl)
delete(cl.channels, ch)
ch.Send(RplPart(ch, cl, message), nil)
}
func (ch *Channel) PrivMsg(cl *Client, message string) {
ch.Send(RplPrivMsgChannel(ch, cl, message), cl)
}
func (ch *Channel) GetTopic(cl *Client) {
if !ch.members[cl] {
cl.send <- ErrNotOnChannel(ch)
return
}
if ch.topic != "" {
cl.send <- RplTopic(ch)
} else {
cl.send <- RplNoTopic(ch)
}
}
func (ch *Channel) ChangeTopic(cl *Client, newTopic string) {
if !ch.members[cl] {
cl.send <- ErrNotOnChannel(ch)
return
}
ch.topic = newTopic
if ch.topic != "" {
ch.Send(RplTopic(ch), nil)
} else {
ch.Send(RplNoTopic(ch), nil)
}
}

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@ -3,34 +3,46 @@ package irc
import (
"fmt"
"net"
"strings"
)
type Client struct {
conn net.Conn
send chan<- string
hostname string
send chan<- Reply
recv <-chan string
username string
realname string
nick string
registered bool
invisible bool
channels ChannelSet
}
type ClientSet map[*Client]bool
func NewClient(conn net.Conn) *Client {
client := new(Client)
client.conn = conn
client.send = StringWriteChan(conn)
client.recv = StringReadChan(conn)
client := &Client{conn: conn, recv: StringReadChan(conn), channels: make(ChannelSet), hostname: LookupHostname(conn.RemoteAddr())}
client.SetReplyToStringChan()
return client
}
func (c *Client) SetReplyToStringChan() {
send := make(chan Reply)
write := StringWriteChan(c.conn)
go func() {
for reply := range send {
write <- reply.String(c)
}
}()
c.send = send
}
// Adapt `chan string` to a `chan Message`.
func (c *Client) Communicate(server chan<- *ClientMessage) {
func (c *Client) Communicate(server *Server) {
for str := range c.recv {
m := ParseMessage(str)
if m != nil {
server <- &ClientMessage{c, m}
server.recv <- &ClientMessage{c, m}
}
}
}
@ -39,7 +51,7 @@ func (c *Client) Nick() string {
if c.nick != "" {
return c.nick
}
return "<guest>"
return "*"
}
func (c *Client) UModeString() string {
@ -57,15 +69,10 @@ func (c *Client) HasUser() bool {
return c.username != ""
}
func (c *Client) Hostname() string {
addr := c.conn.RemoteAddr().String()
index := strings.LastIndex(addr, ":")
if index != -1 {
return addr[0:index]
}
return addr
func (c *Client) UserHost() string {
return fmt.Sprintf("%s!%s@%s", c.nick, c.username, c.hostname)
}
func (c *Client) UserHost() string {
return fmt.Sprintf("%s!%s@%s", c.nick, c.username, c.Hostname())
func (c *Client) Id() string {
return c.UserHost()
}

View File

@ -4,68 +4,180 @@ type Message interface {
Handle(s *Server, c *Client)
}
func (m *NickMessage) Handle(s *Server, c *Client) {
if s.nicks[m.nickname] != nil {
c.send <- ErrNickNameInUse(m.nickname)
return
}
oldNick := c.nick
if c.nick != "" {
delete(s.nicks, c.nick)
}
c.nick = m.nickname
s.nicks[c.nick] = c
if c.registered {
c.send <- ReplyNick(oldNick, c)
} else {
tryRegister(s, c)
}
}
// unknown
func (m *UserMessage) Handle(s *Server, c *Client) {
if c.username != "" {
c.send <- ErrAlreadyRegistered(c.Nick())
return
}
c.username, c.realname = m.user, m.realname
tryRegister(s, c)
}
func (m *QuitMessage) Handle(s *Server, c *Client) {
c.send <- MessageError()
c.conn.Close()
delete(s.nicks, c.nick)
type UnknownMessage struct {
command string
}
func (m *UnknownMessage) Handle(s *Server, c *Client) {
c.send <- ErrUnknownCommand(c.Nick(), m.command)
c.send <- ErrUnknownCommand(s, m.command)
}
// PING
type PingMessage struct {
server string
server2 string
}
func (m *PingMessage) Handle(s *Server, c *Client) {
c.send <- MessagePong()
c.send <- RplPong(s)
}
// PONG
type PongMessage struct {
server1 string
server2 string
}
func (m *PongMessage) Handle(s *Server, c *Client) {
// TODO update client atime
}
// NICK
type NickMessage struct {
nickname string
}
func (m *NickMessage) Handle(s *Server, c *Client) {
s.ChangeNick(c, m.nickname)
}
// USER
type UserMessage struct {
user string
mode uint8
unused string
realname string
}
func (m *UserMessage) Handle(s *Server, c *Client) {
s.Register(c, m.user, m.realname)
}
// QUIT
type QuitMessage struct {
message string
}
func (m *QuitMessage) Handle(s *Server, c *Client) {
s.Quit(c, m.message)
}
// MODE
type ModeMessage struct {
nickname string
modes []string
}
func (m *ModeMessage) Handle(s *Server, c *Client) {
if m.nickname != c.nick {
c.send <- ErrUsersDontMatch(c.Nick())
c.send <- ErrUsersDontMatch(s)
return
}
for _, mode := range m.modes {
if mode == "+i" {
c.invisible = true
} else if mode == "-i" {
c.invisible = false
}
}
c.send <- ReplyUModeIs(c)
s.ChangeUserMode(c, m.modes)
}
func tryRegister(s *Server, c *Client) {
if (!c.registered && c.HasNick() && c.HasUser()) {
c.registered = true
c.send <- ReplyWelcome(c)
c.send <- ReplyYourHost(c.Nick(), s.name)
c.send <- ReplyCreated(c.Nick(), s.ctime)
c.send <- ReplyMyInfo(c.Nick(), s.name)
// JOIN
type JoinMessage struct {
channels []string
keys []string
zero bool
}
func (m *JoinMessage) Handle(s *Server, c *Client) {
if m.zero {
for channel := range c.channels {
channel.Part(c, "")
}
} else {
for i, name := range m.channels {
key := ""
if len(m.keys) > i {
key = m.keys[i]
}
s.GetOrMakeChannel(name).Join(c, key)
}
}
}
// PART
type PartMessage struct {
channels []string
message string
}
func (m *PartMessage) Handle(s *Server, c *Client) {
for _, chname := range m.channels {
channel := s.channels[chname]
if channel == nil {
c.send <- ErrNoSuchChannel(s, chname)
continue
}
channel.Part(c, m.message)
}
}
// PRIVMSG
type PrivMsgMessage struct {
target string
message string
}
func (m *PrivMsgMessage) TargetIsChannel() bool {
switch m.target[0] {
case '&', '#', '+', '!':
return true
}
return false
}
func (m *PrivMsgMessage) Handle(s *Server, c *Client) {
if m.TargetIsChannel() {
channel := s.channels[m.target]
if channel != nil {
channel.PrivMsg(c, m.message)
} else {
c.send <- ErrNoSuchNick(s, m.target)
}
} else {
client := s.nicks[m.target]
if client != nil {
client.send <- RplPrivMsg(client, m.message)
} else {
c.send <- ErrNoSuchNick(s, m.target)
}
}
}
// TOPIC
type TopicMessage struct {
channel string
topic string
}
func (m *TopicMessage) Handle(s *Server, c *Client) {
channel := s.channels[m.channel]
if channel == nil {
c.send <- ErrNoSuchChannel(s, m.channel)
return
}
if m.topic == "" {
channel.GetTopic(c)
} else {
channel.ChangeTopic(c, m.topic)
}
}

View File

@ -1,4 +1,6 @@
// http://tools.ietf.org/html/rfc2812
// channel management: http://tools.ietf.org/html/rfc2811
// client protocol: http://tools.ietf.org/html/rfc2812
// server protocol: http://tools.ietf.org/html/rfc2813
package irc
const (
@ -6,22 +8,30 @@ const (
)
const (
RPL_WELCOME = "001"
RPL_YOURHOST = "002"
RPL_CREATED = "003"
RPL_MYINFO = "004"
RPL_UMODEIS = "221"
RPL_INFO = "371"
RPL_NICK = "NICK"
)
const (
ERR_NOSUCHNICK = "401"
ERR_NOSUCHSERVER = "402"
ERR_NOSUCHCHANNEL = "403"
ERR_UNKNOWNCOMMAND = "421"
ERR_NICKNAMEINUSE = "433"
ERR_NEEDMOREPARAMS = "461"
ERR_ALREADYREGISTRED = "462"
ERR_USERSDONTMATCH = "502"
RPL_WELCOME = "001"
RPL_YOURHOST = "002"
RPL_CREATED = "003"
RPL_MYINFO = "004"
RPL_UMODEIS = "221"
RPL_NOTOPIC = "331"
RPL_TOPIC = "332"
RPL_NAMREPLY = "353"
RPL_ENDOFNAMES = "366"
RPL_INFO = "371"
ERR_NOSUCHNICK = "401"
ERR_NOSUCHSERVER = "402"
ERR_NOSUCHCHANNEL = "403"
ERR_UNKNOWNCOMMAND = "421"
ERR_NICKNAMEINUSE = "433"
ERR_NOTONCHANNEL = "442"
ERR_NEEDMOREPARAMS = "461"
ERR_ALREADYREGISTRED = "462"
ERR_INVITEONLYCHANNEL = "473"
ERR_BADCHANNELKEY = "475"
ERR_USERSDONTMATCH = "502"
RPL_JOIN = "JOIN"
RPL_NICK = "NICK"
RPL_PART = "PART"
RPL_PONG = "PONG"
RPL_PRIVMSG = "PRIVMSG"
)

View File

@ -1,27 +0,0 @@
package irc
type NickMessage struct {
nickname string
}
type UserMessage struct {
user string
mode uint8
unused string
realname string
}
type QuitMessage struct {
message string
}
type UnknownMessage struct {
command string
}
type PingMessage struct {}
type ModeMessage struct {
nickname string
modes []string
}

View File

@ -3,8 +3,8 @@ package irc
import (
"bufio"
"log"
"strings"
"net"
"strings"
)
func readTrimmedLine(reader *bufio.Reader) (string, error) {
@ -20,7 +20,7 @@ func StringReadChan(conn net.Conn) <-chan string {
go func() {
for {
line, err := readTrimmedLine(reader)
if (line != "") {
if line != "" {
ch <- line
log.Printf("%s -> %s", addr, line)
}
@ -50,3 +50,16 @@ func StringWriteChan(conn net.Conn) chan<- string {
return ch
}
func LookupHostname(addr net.Addr) string {
addrStr := addr.String()
ipaddr, _, err := net.SplitHostPort(addrStr)
if err != nil {
return addrStr
}
names, err := net.LookupAddr(ipaddr)
if err != nil {
return ipaddr
}
return names[0]
}

View File

@ -7,12 +7,17 @@ import (
"strings"
)
var commands = map[string]func([]string) Message {
"MODE": NewModeMessage,
"NICK": NewNickMessage,
"PING": NewPingMessage,
"QUIT": NewQuitMessage,
"USER": NewUserMessage,
var commands = map[string]func([]string) Message{
"JOIN": NewJoinMessage,
"MODE": NewModeMessage,
"NICK": NewNickMessage,
"PART": NewPartMessage,
"PING": NewPingMessage,
"PONG": NewPongMessage,
"PRIVMSG": NewPrivMsgMessage,
"QUIT": NewQuitMessage,
"TOPIC": NewTopicMessage,
"USER": NewUserMessage,
}
func ParseMessage(line string) Message {
@ -54,7 +59,6 @@ func parseLine(line string) (string, []string) {
return args[0], args[1:]
}
// []string => Message constructors
func NewNickMessage(args []string) Message {
@ -65,7 +69,25 @@ func NewNickMessage(args []string) Message {
}
func NewPingMessage(args []string) Message {
return &PingMessage{}
if len(args) < 1 {
return nil
}
message := &PingMessage{server: args[0]}
if len(args) > 1 {
message.server2 = args[1]
}
return message
}
func NewPongMessage(args []string) Message {
if len(args) < 1 {
return nil
}
message := &PongMessage{server1: args[0]}
if len(args) > 1 {
message.server2 = args[1]
}
return message
}
func NewQuitMessage(args []string) Message {
@ -112,3 +134,55 @@ func NewModeMessage(args []string) Message {
}
return msg
}
func NewJoinMessage(args []string) Message {
msg := new(JoinMessage)
if len(args) > 0 {
if args[0] == "0" {
msg.zero = true
} else {
msg.channels = strings.Split(args[0], ",")
}
if len(args) > 1 {
msg.keys = strings.Split(args[1], ",")
}
}
return msg
}
func NewPartMessage(args []string) Message {
if len(args) < 1 {
return nil
}
msg := new(PartMessage)
msg.channels = strings.Split(args[0], ",")
if len(args) > 1 {
msg.message = args[1]
}
return msg
}
func NewPrivMsgMessage(args []string) Message {
if len(args) < 2 {
return nil
}
return &PrivMsgMessage{target: args[0], message: args[1]}
}
func NewTopicMessage(args []string) Message {
if len(args) < 1 {
return nil
}
message := &TopicMessage{channel: args[0]}
if len(args) > 1 {
message.topic = args[1]
}
return message
}

148
src/irc/reply.go Normal file
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@ -0,0 +1,148 @@
package irc
import (
"fmt"
"time"
)
type Identifier interface {
Id() string
}
type Reply interface {
String(client *Client) string
}
type BasicReply struct {
source Identifier
code string
message string
}
func (reply *BasicReply) String(client *Client) string {
prefix := fmt.Sprintf(":%s %s %s ", reply.source.Id(), reply.code, client.Nick())
return prefix + reply.message
}
type ChannelReply struct {
*BasicReply
channel *Channel
}
func (reply *ChannelReply) String(client *Client) string {
prefix := fmt.Sprintf(":%s %s %s ", reply.source.Id(), reply.code, reply.channel.name)
return prefix + reply.message
}
func NewReply(source Identifier, code string, message string) *BasicReply {
return &BasicReply{source, code, message}
}
// messaging
func RplPrivMsg(source *Client, message string) Reply {
return NewReply(source, RPL_PRIVMSG, ":"+message)
}
func RplNick(client *Client, newNick string) Reply {
return NewReply(client, RPL_NICK, ":"+newNick)
}
func RplPrivMsgChannel(channel *Channel, source *Client, message string) Reply {
return &ChannelReply{NewReply(source, RPL_PRIVMSG, ":"+message), channel}
}
func RplJoin(channel *Channel, client *Client) Reply {
return &ChannelReply{NewReply(client, RPL_JOIN, channel.name), channel}
}
func RplPart(channel *Channel, client *Client, message string) Reply {
return &ChannelReply{NewReply(client, RPL_PART, ":"+message), channel}
}
// Server Info
func RplWelcome(source Identifier, client *Client) Reply {
return NewReply(source, RPL_WELCOME, "Welcome to the Internet Relay Network "+client.Id())
}
func RplYourHost(server *Server, target *Client) Reply {
return NewReply(server, RPL_YOURHOST, fmt.Sprintf("Your host is %s, running version %s", server.hostname, VERSION))
}
func RplCreated(server *Server) Reply {
return NewReply(server, RPL_CREATED, "This server was created "+server.ctime.Format(time.RFC1123))
}
func RplMyInfo(server *Server) Reply {
return NewReply(server, RPL_MYINFO, server.name+" i ik")
}
func RplUModeIs(server *Server, client *Client) Reply {
return NewReply(server, RPL_UMODEIS, client.UModeString())
}
// channel operations
func RplNoTopic(channel *Channel) Reply {
return &ChannelReply{NewReply(channel.server, RPL_NOTOPIC, channel.name+" :No topic is set"), channel}
}
func RplTopic(channel *Channel) Reply {
return &ChannelReply{NewReply(channel.server, RPL_TOPIC, fmt.Sprintf("%s :%s", channel.name, channel.topic)), channel}
}
func RplNamReply(channel *Channel, client *Client) Reply {
// TODO multiple names and splitting based on message size
return NewReply(channel.server, RPL_NAMREPLY, fmt.Sprintf("=%s :+%s", channel.name, client.Nick()))
}
func RplEndOfNames(source Identifier) Reply {
return NewReply(source, RPL_ENDOFNAMES, ":End of NAMES list")
}
func RplPong(server *Server) Reply {
return NewReply(server, RPL_PONG, "")
}
// errors
func ErrAlreadyRegistered(source Identifier) Reply {
return NewReply(source, ERR_ALREADYREGISTRED, ":You may not reregister")
}
func ErrNickNameInUse(source Identifier, nick string) Reply {
return NewReply(source, ERR_NICKNAMEINUSE, nick+" :Nickname is already in use")
}
func ErrUnknownCommand(source Identifier, command string) Reply {
return NewReply(source, ERR_UNKNOWNCOMMAND, command+" :Unknown command")
}
func ErrUsersDontMatch(source Identifier) Reply {
return NewReply(source, ERR_USERSDONTMATCH, ":Cannot change mode for other users")
}
func ErrNeedMoreParams(source Identifier, command string) Reply {
return NewReply(source, ERR_NEEDMOREPARAMS, command+"%s :Not enough parameters")
}
func ErrNoSuchChannel(source Identifier, channel string) Reply {
return NewReply(source, ERR_NOSUCHCHANNEL, channel+" :No such channel")
}
func ErrNotOnChannel(channel *Channel) Reply {
return NewReply(channel.server, ERR_NOTONCHANNEL, channel.name+" :You're not on that channel")
}
func ErrInviteOnlyChannel(channel *Channel) Reply {
return NewReply(channel.server, ERR_INVITEONLYCHANNEL, channel.name+" :Cannot join channel (+i)")
}
func ErrBadChannelKey(channel *Channel) Reply {
return NewReply(channel.server, ERR_BADCHANNELKEY, channel.name+" :Cannot join channel (+k)")
}
func ErrNoSuchNick(source Identifier, nick string) Reply {
return NewReply(source, ERR_NOSUCHNICK, nick+" :No such nick/channel")
}

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@ -1,54 +0,0 @@
package irc
import (
"fmt"
"time"
)
func ReplyNick(oldNick string, c *Client) string {
return fmt.Sprintf(":%s!%s@%s %s :%s", oldNick, c.username, c.Hostname(), RPL_NICK, c.Nick())
}
func ReplyWelcome(c *Client) string {
return fmt.Sprintf("%s %s Welcome to the Internet Relay Network %s!%s@%s", RPL_WELCOME, c.Nick(), c.Nick(), c.username, c.Hostname())
}
func ReplyYourHost(nick string, server string) string {
return fmt.Sprintf("%s %s Your host is %s, running version %s", RPL_YOURHOST, nick, server, VERSION)
}
func ReplyCreated(nick string, ctime time.Time) string {
return fmt.Sprintf("%s %s This server was created %s", RPL_CREATED, nick, ctime.Format(time.RFC1123))
}
func ReplyMyInfo(nick string, servername string) string {
return fmt.Sprintf("%s %s %s %s i <channel modes>", RPL_MYINFO, nick, servername, VERSION)
}
func ReplyUModeIs(c *Client) string {
return fmt.Sprintf("%s %s %s", RPL_UMODEIS, c.Nick(), c.UModeString())
}
func ErrAlreadyRegistered(nick string) string {
return fmt.Sprintf("%s %s :You may not reregister", ERR_ALREADYREGISTRED, nick)
}
func ErrNickNameInUse(nick string) string {
return fmt.Sprintf("%s %s :Nickname is already in use", ERR_NICKNAMEINUSE, nick)
}
func ErrUnknownCommand(nick string, command string) string {
return fmt.Sprintf("%s %s %s :Unknown command", ERR_UNKNOWNCOMMAND, nick, command)
}
func ErrUsersDontMatch(nick string) string {
return fmt.Sprintf("%s %s :Cannot change mode for other users", ERR_USERSDONTMATCH, nick)
}
func MessagePong() string {
return "PONG"
}
func MessageError() string {
return "ERROR :Bye"
}

View File

@ -7,24 +7,27 @@ import (
)
type Server struct {
ctime time.Time
name string
ch chan *ClientMessage
nicks map[string]*Client
hostname string
ctime time.Time
name string
recv chan<- *ClientMessage
nicks map[string]*Client
channels map[string]*Channel
}
type ClientMessage struct {
client *Client
client *Client
message Message
}
func NewServer(name string) *Server {
server := new(Server)
server.ctime = time.Now()
server.name = name
server.ch = make(chan *ClientMessage)
server.nicks = make(map[string]*Client)
go server.Receive()
recv := make(chan *ClientMessage)
server := &Server{ctime: time.Now(), name: name, recv: recv, nicks: make(map[string]*Client), channels: make(map[string]*Channel)}
go func() {
for m := range recv {
m.message.Handle(server, m.client)
}
}()
return server
}
@ -34,18 +37,104 @@ func (s *Server) Listen(addr string) {
log.Fatal("Server.Listen: ", err)
}
s.hostname = LookupHostname(listener.Addr())
log.Print("Server.Listen: listening on ", addr)
for {
conn, err := listener.Accept()
if err != nil {
log.Print("Server.Listen: ", err)
continue
}
go NewClient(conn).Communicate(s.ch)
log.Print("Server.Listen: accepted ", conn.RemoteAddr())
go NewClient(conn).Communicate(s)
}
}
func (s *Server) Receive() {
for m := range s.ch {
m.message.Handle(s, m.client)
func (s *Server) GetOrMakeChannel(name string) *Channel {
channel := s.channels[name]
if channel == nil {
channel = NewChannel(s, name)
s.channels[name] = channel
}
return channel
}
// Send a message to clients of channels fromClient is a member.
func (s *Server) SendToInterestedClients(fromClient *Client, reply Reply) {
clients := make(map[*Client]bool)
for channel := range fromClient.channels {
for client := range channel.members {
clients[client] = true
}
}
for client := range clients {
client.send <- reply
}
}
// server functionality
func (s *Server) ChangeNick(c *Client, newNick string) {
if s.nicks[newNick] != nil {
c.send <- ErrNickNameInUse(s, newNick)
return
}
s.SendToInterestedClients(c, RplNick(c, newNick))
if c.nick != "" {
delete(s.nicks, c.nick)
}
c.nick = newNick
s.nicks[c.nick] = c
s.TryRegister(c)
}
func (s *Server) Register(c *Client, user string, realName string) {
if c.username != "" {
c.send <- ErrAlreadyRegistered(s)
return
}
c.username, c.realname = user, realName
s.TryRegister(c)
}
func (s *Server) TryRegister(c *Client) {
if !c.registered && c.HasNick() && c.HasUser() {
c.registered = true
c.send <- RplWelcome(s, c)
c.send <- RplYourHost(s, c)
c.send <- RplCreated(s)
c.send <- RplMyInfo(s)
}
}
func (s *Server) Quit(c *Client, message string) {
for channel := range c.channels {
channel.Part(c, message)
}
delete(s.nicks, c.nick)
c.conn.Close()
}
func (s *Server) ChangeUserMode(c *Client, modes []string) {
for _, mode := range modes {
if mode == "+i" {
c.invisible = true
} else if mode == "-i" {
c.invisible = false
}
}
c.send <- RplUModeIs(s, c)
}
func (s *Server) Id() string {
return s.hostname
}