source: code/trunk/upstream.go@ 18

package jounce

import (
        "crypto/tls"
        "fmt"
        "io"
        "net"
        "strings"

        "gopkg.in/irc.v3"
)

const (
        rpl_localusers  = "265"
        rpl_globalusers = "266"
)

type modeSet string

func (ms modeSet) Has(c byte) bool {
        return strings.IndexByte(string(ms), c) >= 0
}

func (ms *modeSet) Add(c byte) {
        if !ms.Has(c) {
                *ms += modeSet(c)
        }
}

func (ms *modeSet) Del(c byte) {
        i := strings.IndexByte(string(*ms), c)
        if i >= 0 {
                *ms = (*ms)[:i] + (*ms)[i+1:]
        }
}

func (ms *modeSet) Apply(s string) error {
        var plusMinus byte
        for i := 0; i < len(s); i++ {
                switch c := s[i]; c {
                case '+', '-':
                        plusMinus = c
                default:
                        switch plusMinus {
                        case '+':
                                ms.Add(c)
                        case '-':
                                ms.Del(c)
                        default:
                                return fmt.Errorf("malformed modestring %q: missing plus/minus", s)
                        }
                }
        }
        return nil
}

type upstreamConn struct {
        upstream   *Upstream
        net        net.Conn
        irc        *irc.Conn
        srv        *Server
        registered bool
        modes      modeSet

        serverName            string
        availableUserModes    string
        availableChannelModes string
        channelModesWithParam string
}

func (c *upstreamConn) handleMessage(msg *irc.Message) error {
        switch msg.Command {
        case "PING":
                // TODO: handle params
                return c.irc.WriteMessage(&irc.Message{
                        Command: "PONG",
                        Params:  []string{c.srv.Hostname},
                })
        case "MODE":
                if len(msg.Params) < 2 {
                        return newNeedMoreParamsError(msg.Command)
                }
                if nick := msg.Params[0]; nick != c.upstream.Nick {
                        return fmt.Errorf("received MODE message for unknow nick %q", nick)
                }
                return c.modes.Apply(msg.Params[1])
        case "NOTICE":
                c.srv.Logger.Printf("%q: %v", c.upstream.Addr, msg)
        case irc.RPL_WELCOME:
                c.registered = true
                c.srv.Logger.Printf("Connection to %q registered", c.upstream.Addr)
        case irc.RPL_MYINFO:
                if len(msg.Params) < 5 {
                        return newNeedMoreParamsError(msg.Command)
                }
                c.serverName = msg.Params[1]
                c.availableUserModes = msg.Params[3]
                c.availableChannelModes = msg.Params[4]
                if len(msg.Params) > 5 {
                        c.channelModesWithParam = msg.Params[5]
                }
        case irc.RPL_YOURHOST, irc.RPL_CREATED:
                // Ignore
        case irc.RPL_LUSERCLIENT, irc.RPL_LUSEROP, irc.RPL_LUSERUNKNOWN, irc.RPL_LUSERCHANNELS, irc.RPL_LUSERME:
                // Ignore
        case irc.RPL_MOTDSTART, irc.RPL_MOTD, irc.RPL_ENDOFMOTD:
                // Ignore
        case rpl_localusers, rpl_globalusers:
                // Ignore
        case irc.RPL_STATSVLINE, irc.RPL_STATSPING, irc.RPL_STATSBLINE, irc.RPL_STATSDLINE:
                // Ignore
        default:
                c.srv.Logger.Printf("Unhandled upstream message: %v", msg)
        }
        return nil
}

func connect(s *Server, upstream *Upstream) error {
        s.Logger.Printf("Connecting to %v", upstream.Addr)

        netConn, err := tls.Dial("tcp", upstream.Addr, nil)
        if err != nil {
                return fmt.Errorf("failed to dial %q: %v", upstream.Addr, err)
        }

        c := upstreamConn{
                upstream: upstream,
                net:      netConn,
                irc:      irc.NewConn(netConn),
                srv:      s,
        }
        defer netConn.Close()

        err = c.irc.WriteMessage(&irc.Message{
                Command: "NICK",
                Params:  []string{upstream.Nick},
        })
        if err != nil {
                return err
        }

        err = c.irc.WriteMessage(&irc.Message{
                Command: "USER",
                Params:  []string{upstream.Username, "0", "*", upstream.Realname},
        })
        if err != nil {
                return err
        }

        for {
                msg, err := c.irc.ReadMessage()
                if err == io.EOF {
                        break
                } else if err != nil {
                        return fmt.Errorf("failed to read IRC command: %v", err)
                }

                if err := c.handleMessage(msg); err != nil {
                        c.srv.Logger.Printf("Failed to handle message %q from %q: %v", msg, upstream.Addr, err)
                }
        }

        return netConn.Close()
}