soju/irc.go
2023-03-01 12:54:43 +01:00

535 lines
12 KiB
Go

package soju
import (
"fmt"
"strings"
"time"
"unicode"
"unicode/utf8"
"gopkg.in/irc.v4"
"git.sr.ht/~emersion/soju/database"
"git.sr.ht/~emersion/soju/xirc"
)
// TODO: generalize and move helpers to the xirc package
type userModes string
func (ms userModes) Has(c byte) bool {
return strings.IndexByte(string(ms), c) >= 0
}
func (ms *userModes) Add(c byte) {
if !ms.Has(c) {
*ms += userModes(c)
}
}
func (ms *userModes) Del(c byte) {
i := strings.IndexByte(string(*ms), c)
if i >= 0 {
*ms = (*ms)[:i] + (*ms)[i+1:]
}
}
func (ms *userModes) 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 channelModeType byte
// standard channel mode types, as explained in https://modern.ircdocs.horse/#mode-message
const (
// modes that add or remove an address to or from a list
modeTypeA channelModeType = iota
// modes that change a setting on a channel, and must always have a parameter
modeTypeB
// modes that change a setting on a channel, and must have a parameter when being set, and no parameter when being unset
modeTypeC
// modes that change a setting on a channel, and must not have a parameter
modeTypeD
)
var stdChannelModes = map[byte]channelModeType{
'b': modeTypeA, // ban list
'e': modeTypeA, // ban exception list
'I': modeTypeA, // invite exception list
'k': modeTypeB, // channel key
'l': modeTypeC, // channel user limit
'i': modeTypeD, // channel is invite-only
'm': modeTypeD, // channel is moderated
'n': modeTypeD, // channel has no external messages
's': modeTypeD, // channel is secret
't': modeTypeD, // channel has protected topic
}
type channelModes map[byte]string
// applyChannelModes parses a mode string and mode arguments from a MODE message,
// and applies the corresponding channel mode and user membership changes on that channel.
//
// If ch.modes is nil, channel modes are not updated.
func applyChannelModes(ch *upstreamChannel, modeStr string, arguments []string) error {
nextArgument := 0
var plusMinus byte
outer:
for i := 0; i < len(modeStr); i++ {
mode := modeStr[i]
if mode == '+' || mode == '-' {
plusMinus = mode
continue
}
if plusMinus != '+' && plusMinus != '-' {
return fmt.Errorf("malformed modestring %q: missing plus/minus", modeStr)
}
for _, membership := range ch.conn.availableMemberships {
if membership.Mode == mode {
if nextArgument >= len(arguments) {
return fmt.Errorf("malformed modestring %q: missing mode argument for %c%c", modeStr, plusMinus, mode)
}
member := arguments[nextArgument]
m := ch.Members.Get(member)
if m != nil {
if plusMinus == '+' {
m.Add(ch.conn.availableMemberships, membership)
} else {
// TODO: for upstreams without multi-prefix, query the user modes again
m.Remove(membership)
}
}
nextArgument++
continue outer
}
}
mt, ok := ch.conn.availableChannelModes[mode]
if !ok {
continue
}
if mt == modeTypeA {
nextArgument++
} else if mt == modeTypeB || (mt == modeTypeC && plusMinus == '+') {
if plusMinus == '+' {
var argument string
// some sentitive arguments (such as channel keys) can be omitted for privacy
// (this will only happen for RPL_CHANNELMODEIS, never for MODE messages)
if nextArgument < len(arguments) {
argument = arguments[nextArgument]
}
if ch.modes != nil {
ch.modes[mode] = argument
}
} else {
delete(ch.modes, mode)
}
nextArgument++
} else if mt == modeTypeC || mt == modeTypeD {
if plusMinus == '+' {
if ch.modes != nil {
ch.modes[mode] = ""
}
} else {
delete(ch.modes, mode)
}
}
}
return nil
}
func (cm channelModes) Format() (modeString string, parameters []string) {
var modesWithValues strings.Builder
var modesWithoutValues strings.Builder
parameters = make([]string, 0, 16)
for mode, value := range cm {
if value != "" {
modesWithValues.WriteString(string(mode))
parameters = append(parameters, value)
} else {
modesWithoutValues.WriteString(string(mode))
}
}
modeString = "+" + modesWithValues.String() + modesWithoutValues.String()
return
}
const stdChannelTypes = "#&+!"
var stdMemberships = []xirc.Membership{
{'q', '~'}, // founder
{'a', '&'}, // protected
{'o', '@'}, // operator
{'h', '%'}, // halfop
{'v', '+'}, // voice
}
func formatMemberPrefix(ms xirc.MembershipSet, dc *downstreamConn) string {
if !dc.caps.IsEnabled("multi-prefix") {
if len(ms) == 0 {
return ""
}
return string(ms[0].Prefix)
}
prefixes := make([]byte, len(ms))
for i, m := range ms {
prefixes[i] = m.Prefix
}
return string(prefixes)
}
func parseMessageParams(msg *irc.Message, out ...*string) error {
if len(msg.Params) < len(out) {
return newNeedMoreParamsError(msg.Command)
}
for i := range out {
if out[i] != nil {
*out[i] = msg.Params[i]
}
}
return nil
}
func copyClientTags(tags irc.Tags) irc.Tags {
t := make(irc.Tags, len(tags))
for k, v := range tags {
if strings.HasPrefix(k, "+") {
t[k] = v
}
}
return t
}
type casemapping func(string) string
func casemapNone(name string) string {
return name
}
// CasemapASCII of name is the canonical representation of name according to the
// ascii casemapping.
func casemapASCII(name string) string {
nameBytes := []byte(name)
for i, r := range nameBytes {
if 'A' <= r && r <= 'Z' {
nameBytes[i] = r + 'a' - 'A'
}
}
return string(nameBytes)
}
// casemapRFC1459 of name is the canonical representation of name according to the
// rfc1459 casemapping.
func casemapRFC1459(name string) string {
nameBytes := []byte(name)
for i, r := range nameBytes {
if 'A' <= r && r <= 'Z' {
nameBytes[i] = r + 'a' - 'A'
} else if r == '{' {
nameBytes[i] = '['
} else if r == '}' {
nameBytes[i] = ']'
} else if r == '\\' {
nameBytes[i] = '|'
} else if r == '~' {
nameBytes[i] = '^'
}
}
return string(nameBytes)
}
// casemapRFC1459Strict of name is the canonical representation of name
// according to the rfc1459-strict casemapping.
func casemapRFC1459Strict(name string) string {
nameBytes := []byte(name)
for i, r := range nameBytes {
if 'A' <= r && r <= 'Z' {
nameBytes[i] = r + 'a' - 'A'
} else if r == '{' {
nameBytes[i] = '['
} else if r == '}' {
nameBytes[i] = ']'
} else if r == '\\' {
nameBytes[i] = '|'
}
}
return string(nameBytes)
}
func parseCasemappingToken(tokenValue string) (casemap casemapping, ok bool) {
switch tokenValue {
case "ascii":
casemap = casemapASCII
case "rfc1459":
casemap = casemapRFC1459
case "rfc1459-strict":
casemap = casemapRFC1459Strict
default:
return nil, false
}
return casemap, true
}
type casemapMap struct {
m map[string]casemapEntry
casemap casemapping
}
type casemapEntry struct {
originalKey string
value interface{}
}
func newCasemapMap() casemapMap {
return casemapMap{
m: make(map[string]casemapEntry),
casemap: casemapNone,
}
}
func (cm *casemapMap) Has(name string) bool {
_, ok := cm.m[cm.casemap(name)]
return ok
}
func (cm *casemapMap) Len() int {
return len(cm.m)
}
func (cm *casemapMap) get(name string) interface{} {
entry, ok := cm.m[cm.casemap(name)]
if !ok {
return nil
}
return entry.value
}
func (cm *casemapMap) set(name string, value interface{}) {
nameCM := cm.casemap(name)
entry, ok := cm.m[nameCM]
if !ok {
cm.m[nameCM] = casemapEntry{
originalKey: name,
value: value,
}
return
}
entry.value = value
cm.m[nameCM] = entry
}
func (cm *casemapMap) Del(name string) {
delete(cm.m, cm.casemap(name))
}
func (cm *casemapMap) SetCasemapping(newCasemap casemapping) {
cm.casemap = newCasemap
m := make(map[string]casemapEntry, len(cm.m))
for _, entry := range cm.m {
m[cm.casemap(entry.originalKey)] = entry
}
cm.m = m
}
type upstreamChannelCasemapMap struct{ casemapMap }
func (cm *upstreamChannelCasemapMap) Get(name string) *upstreamChannel {
if v := cm.get(name); v == nil {
return nil
} else {
return v.(*upstreamChannel)
}
}
func (cm *upstreamChannelCasemapMap) Set(uch *upstreamChannel) {
cm.set(uch.Name, uch)
}
func (cm *upstreamChannelCasemapMap) ForEach(f func(*upstreamChannel)) {
for _, entry := range cm.m {
f(entry.value.(*upstreamChannel))
}
}
type upstreamUserCasemapMap struct{ casemapMap }
func (cm *upstreamUserCasemapMap) Get(name string) *upstreamUser {
if v := cm.get(name); v == nil {
return nil
} else {
return v.(*upstreamUser)
}
}
func (cm *upstreamUserCasemapMap) Set(u *upstreamUser) {
cm.set(u.Nickname, u)
}
type channelCasemapMap struct{ casemapMap }
func (cm *channelCasemapMap) Get(name string) *database.Channel {
if v := cm.get(name); v == nil {
return nil
} else {
return v.(*database.Channel)
}
}
func (cm *channelCasemapMap) Set(ch *database.Channel) {
cm.set(ch.Name, ch)
}
func (cm *channelCasemapMap) ForEach(f func(*database.Channel)) {
for _, entry := range cm.m {
f(entry.value.(*database.Channel))
}
}
type membershipsCasemapMap struct{ casemapMap }
func (cm *membershipsCasemapMap) Get(name string) *xirc.MembershipSet {
if v := cm.get(name); v == nil {
return nil
} else {
return v.(*xirc.MembershipSet)
}
}
func (cm *membershipsCasemapMap) Set(name string, ms *xirc.MembershipSet) {
cm.set(name, ms)
}
func (cm *membershipsCasemapMap) ForEach(f func(string, *xirc.MembershipSet)) {
for _, entry := range cm.m {
f(entry.originalKey, entry.value.(*xirc.MembershipSet))
}
}
type deliveredCasemapMap struct{ casemapMap }
func (cm *deliveredCasemapMap) Get(name string) deliveredClientMap {
if v := cm.get(name); v == nil {
return nil
} else {
return v.(deliveredClientMap)
}
}
func (cm *deliveredCasemapMap) Set(name string, m deliveredClientMap) {
cm.set(name, m)
}
func (cm *deliveredCasemapMap) ForEach(f func(string, deliveredClientMap)) {
for _, entry := range cm.m {
f(entry.originalKey, entry.value.(deliveredClientMap))
}
}
type monitorCasemapMap struct{ casemapMap }
func (cm *monitorCasemapMap) Get(name string) (online bool) {
if v := cm.get(name); v == nil {
return false
} else {
return v.(bool)
}
}
func (cm *monitorCasemapMap) Set(name string, online bool) {
cm.set(name, online)
}
func (cm *monitorCasemapMap) ForEach(f func(name string, online bool)) {
for _, entry := range cm.m {
f(entry.originalKey, entry.value.(bool))
}
}
type pushTargetCasemapMap struct{ casemapMap }
func (cm *pushTargetCasemapMap) Get(name string) (last time.Time) {
if v := cm.get(name); v == nil {
return time.Time{}
} else {
return v.(time.Time)
}
}
func (cm *pushTargetCasemapMap) Set(name string, last time.Time) {
cm.set(name, last)
}
func isWordBoundary(r rune) bool {
switch r {
case '-', '_', '|': // inspired from weechat.look.highlight_regex
return false
default:
return !unicode.IsLetter(r) && !unicode.IsNumber(r)
}
}
func isHighlight(text, nick string) bool {
for {
i := strings.Index(text, nick)
if i < 0 {
return false
}
left, _ := utf8.DecodeLastRuneInString(text[:i])
right, _ := utf8.DecodeRuneInString(text[i+len(nick):])
if isWordBoundary(left) && isWordBoundary(right) {
return true
}
text = text[i+len(nick):]
}
}
// parseChatHistoryBound parses the given CHATHISTORY parameter as a bound.
// The zero time is returned on error.
func parseChatHistoryBound(param string) time.Time {
parts := strings.SplitN(param, "=", 2)
if len(parts) != 2 {
return time.Time{}
}
switch parts[0] {
case "timestamp":
timestamp, err := time.Parse(xirc.ServerTimeLayout, parts[1])
if err != nil {
return time.Time{}
}
return timestamp
default:
return time.Time{}
}
}
func isNumeric(cmd string) bool {
if len(cmd) != 3 {
return false
}
for i := 0; i < 3; i++ {
if cmd[i] < '0' || cmd[i] > '9' {
return false
}
}
return true
}