package main
import (
"crypto/rand"
"log/slog"
"math/big"
"net"
"sync"
)
type Client struct {
conn *net.Conn
UID string
Nick string
Ident string
Gecos string
Host string
Caps map[string]struct{}
Extra map[string]any
Server Server
State ClientState
}
func (client *Client) Send(msg SMsg) error {
return client.SendRaw(msg.ClientSerialize())
}
func (client *Client) SendRaw(s string) error {
if client.conn == nil {
panic("not implemented")
}
slog.Debug("send", "line", s, "conn", client.conn)
_, err := (*client.conn).Write([]byte(s))
if err != nil {
// TODO: Should shut down the netFd instead but the stdlib
// doesn't expose a way to do this.
(*client.conn).Close()
return err
}
return nil
}
func (client Client) ClientSource() string {
// TODO: Edge cases where these aren't available
return client.Nick + "!" + client.Ident + "@" + client.Host
}
func (client Client) ServerSource() string {
return client.UID
}
func (client *Client) Teardown() {
if client.conn != nil {
(*client.conn).Close()
}
if !uidToClient.CompareAndDelete(client.UID, client) {
slog.Error("uid inconsistent", "uid", client.UID, "client", client)
}
if (client.State >= ClientStateRegistered || client.Nick != "*") {
if !nickToClient.CompareAndDelete(client.Nick, client) {
slog.Error("nick inconsistent", "nick", client.Nick, "client", client)
}
}
}
func NewLocalClient(conn *net.Conn) (*Client, error) {
client := &Client{
conn: conn,
Server: self,
State: ClientStatePreRegistration,
Nick: "*",
Caps: make(map[string]struct{}),
Extra: make(map[string]any),
}
for range 10 {
uid_ := []byte(self.SID)
for range 6 {
randint, err := rand.Int(rand.Reader, big.NewInt(26))
if err != nil {
return nil, err
}
uid_ = append(uid_, byte(65+randint.Uint64()))
}
uid := string(uid_)
_, exists := uidToClient.LoadOrStore(uid, client)
if !exists {
client.UID = uid
return client, nil
}
}
return nil, ErrUIDBusy
}
func (client *Client) checkRegistration() error {
switch client.State {
case ClientStatePreRegistration:
if client.Nick != "*" && client.Ident != "" {
client.State = ClientStateRegistered
return client.Send(MakeMsg(self, RPL_WELCOME, client.Nick, "Welcome"))
}
return nil // Incomplete for registration
case ClientStateCapabilitiesFinished:
if client.Nick != "*" && client.Ident != "" {
client.State = ClientStateRegistered
return client.Send(MakeMsg(self, RPL_WELCOME, client.Nick, "Welcome"))
}
return nil
default:
return nil
}
}
type ClientState uint8
const (
ClientStatePreRegistration ClientState = iota
ClientStateCapabilities
ClientStateCapabilitiesFinished
ClientStateRegistered
ClientStateRemote
)
var (
uidToClient = sync.Map{}
nickToClient = sync.Map{}
)
