Reject MUC nickname change attempts

Makefile

@@ -2,7 +2,7 @@
 
 COMMIT := $(shell git rev-parse --short HEAD)
 TD_COMMIT := "8517026415e75a8eec567774072cbbbbb52376c1"
-VERSION := "v1.8.2"
+VERSION := "v2.0.0-dev"
 MAKEOPTS := "-j4"
 
 all:

go.mod

@@ -33,5 +33,5 @@ require (
 	nhooyr.io/websocket v1.6.5 // indirect
 )
 
-replace gosrc.io/xmpp => dev.narayana.im/narayana/go-xmpp v0.0.0-20220524203317-306b4ff58e8f
+replace gosrc.io/xmpp => dev.narayana.im/narayana/go-xmpp v0.0.0-20220708184440-35d9cd68e55f
 replace github.com/zelenin/go-tdlib => dev.narayana.im/narayana/go-tdlib v0.0.0-20230730021136-47da33180615

go.sum

@@ -3,6 +3,10 @@ dev.narayana.im/narayana/go-tdlib v0.0.0-20230730021136-47da33180615 h1:RRUZJSro
 dev.narayana.im/narayana/go-tdlib v0.0.0-20230730021136-47da33180615/go.mod h1:Xs8fXbk5n7VaPyrSs9DP7QYoBScWYsjX+lUcWmx1DIU=
 dev.narayana.im/narayana/go-xmpp v0.0.0-20220524203317-306b4ff58e8f h1:6249ajbMjgYz53Oq0IjTvjHXbxTfu29Mj1J/6swRHs4=
 dev.narayana.im/narayana/go-xmpp v0.0.0-20220524203317-306b4ff58e8f/go.mod h1:L3NFMqYOxyLz3JGmgFyWf7r9htE91zVGiK40oW4RwdY=
+dev.narayana.im/narayana/go-xmpp v0.0.0-20220708184440-35d9cd68e55f h1:aT50UsPH1dLje9CCAquRRhr7I9ZvL3kQU6WIWTe8PZ0=
+dev.narayana.im/narayana/go-xmpp v0.0.0-20220708184440-35d9cd68e55f/go.mod h1:L3NFMqYOxyLz3JGmgFyWf7r9htE91zVGiK40oW4RwdY=
+github.com/Arman92/go-tdlib v0.0.0-20191002071913-526f4e1d15f7 h1:GbV1Lv3lVHsSeKAqPTBem72OCsGjXntW4jfJdXciE+w=
+github.com/Arman92/go-tdlib v0.0.0-20191002071913-526f4e1d15f7/go.mod h1:ZzkRfuaFj8etIYMj/ECtXtgfz72RE6U+dos27b3XIwk=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/agnivade/wasmbrowsertest v0.3.1/go.mod h1:zQt6ZTdl338xxRaMW395qccVE2eQm0SjC/SDz0mPWQI=
 github.com/cespare/xxhash/v2 v2.1.1/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=

persistence/sessions.go

@@ -39,6 +39,7 @@ type Session struct {
 	KeepOnline  bool   `yaml:":keeponline"`
 	RawMessages bool   `yaml:":rawmessages"`
 	AsciiArrows bool   `yaml:":asciiarrows"`
+	MUC         bool   `yaml:":muc"`
 	OOBMode     bool   `yaml:":oobmode"`
 	Carbons     bool   `yaml:":carbons"`
 	HideIds     bool   `yaml:":hideids"`
@@ -49,6 +50,7 @@ var configKeys = []string{
 	"keeponline",
 	"rawmessages",
 	"asciiarrows",
+	"muc",
 	"oobmode",
 	"carbons",
 	"hideids",
@@ -124,6 +126,8 @@ func (s *Session) Get(key string) (string, error) {
 		return fromBool(s.RawMessages), nil
 	case "asciiarrows":
 		return fromBool(s.AsciiArrows), nil
+	case "muc":
+		return fromBool(s.MUC), nil
 	case "oobmode":
 		return fromBool(s.OOBMode), nil
 	case "carbons":
@@ -173,6 +177,13 @@ func (s *Session) Set(key string, value string) (string, error) {
 		}
 		s.AsciiArrows = b
 		return value, nil
+	case "muc":
+		b, err := toBool(value)
+		if err != nil {
+			return "", err
+		}
+		s.MUC = b
+		return value, nil
 	case "oobmode":
 		b, err := toBool(value)
 		if err != nil {

persistence/sessions_test.go

@@ -47,12 +47,14 @@ func TestSessionToMap(t *testing.T) {
 	session := Session{
 		Timezone:    "klsf",
 		RawMessages: true,
+		MUC:         true,
 		OOBMode:     true,
 	}
 	m := session.ToMap()
 	sample := map[string]string{
 		"timezone":    "klsf",
 		"keeponline":  "false",
+		"muc":         "true",
 		"rawmessages": "true",
 		"asciiarrows": "false",
 		"oobmode":     "true",

telegabber.go

@@ -15,7 +15,7 @@ import (
 	goxmpp "gosrc.io/xmpp"
 )
 
-var version string = "1.8.2"
+var version string = "2.0.0-dev"
 var commit string
 
 var sm *goxmpp.StreamManager

telegram/client.go

@@ -41,6 +41,25 @@ type DelayedStatus struct {
 	TimestampExpired int64
 }
 
+// MUCState holds MUC metadata
+type MUCState struct {
+	Resources map[string]bool
+	Members   map[int64]*MUCMember
+}
+
+// MUCMember represents a MUC member
+type MUCMember struct {
+	Nickname    string
+	Affiliation string
+}
+
+func NewMUCState() *MUCState {
+	return &MUCState{
+		Resources: make(map[string]bool),
+		Members:   make(map[int64]*MUCMember),
+	}
+}
+
 // Client stores the metadata for lazily invoked TDlib instance
 type Client struct {
 	client     *client.Client
@@ -64,6 +83,8 @@ type Client struct {
 	lastMsgHashes map[int64]uint64
 	msgHashSeed   maphash.Seed
 
+	mucCache map[int64]*MUCState
+
 	locks           clientLocks
 	SendMessageLock sync.Mutex
 }
@@ -73,6 +94,7 @@ type clientLocks struct {
 	chatMessageLocks   map[int64]*sync.Mutex
 	resourcesLock      sync.Mutex
 	outboxLock         sync.Mutex
+	mucCacheLock       sync.Mutex
 	lastMsgHashesLock  sync.Mutex
 
 	authorizerReadLock  sync.Mutex
@@ -133,6 +155,7 @@ func NewClient(conf config.TelegramConfig, jid string, component *xmpp.Component
 		Session:         session,
 		resources:       make(map[string]bool),
 		outbox:          make(map[string]string),
+		mucCache:        make(map[int64]*MUCState),
 		content:         &conf.Content,
 		cache:           cache.NewCache(),
 		options:         options,

telegram/commands.go

@@ -193,23 +193,6 @@ func (c *Client) unsubscribe(chatID int64) error {
 	)
 }
 
-func (c *Client) sendMessagesReverse(chatID int64, messages []*client.Message) {
-	for i := len(messages) - 1; i >= 0; i-- {
-		message := messages[i]
-		reply, _ := c.getMessageReply(message)
-
-		gateway.SendMessage(
-			c.jid,
-			strconv.FormatInt(chatID, 10),
-			c.formatMessage(0, 0, false, message),
-			strconv.FormatInt(message.Id, 10),
-			c.xmpp,
-			reply,
-			false,
-		)
-	}
-}
-
 func (c *Client) usernameOrIDToID(username string) (int64, error) {
 	userID, err := strconv.ParseInt(username, 10, 64)
 	// couldn't parse the id, try to lookup as a username
@@ -1005,7 +988,7 @@ func (c *Client) ProcessChatCommand(chatID int64, cmdline string) (string, bool)
 			return err.Error(), true
 		}
 
-		c.sendMessagesReverse(chatID, messages.Messages)
+		c.sendMessagesReverse(chatID, messages.Messages, true, "")
 	// get latest entries from history
 	case "history":
 		var limit int32 = 10
@@ -1016,32 +999,11 @@ func (c *Client) ProcessChatCommand(chatID int64, cmdline string) (string, bool)
 			}
 		}
 
-		var newMessages *client.Messages
+		messages, err := c.getNLastMessages(chatID, limit)
-		var messages []*client.Message
-		var err error
-		var fromId int64
-		for _ = range make([]struct{}, limit) { // safety limit
-			if len(messages) > 0 {
-				fromId = messages[len(messages)-1].Id
-			}
-
-			newMessages, err = c.client.GetChatHistory(&client.GetChatHistoryRequest{
-				ChatId:        chatID,
-				FromMessageId: fromId,
-				Limit:         limit,
-			})
 		if err != nil {
 			return err.Error(), true
 		}
-
+		c.sendMessagesReverse(chatID, messages, true, "")
-			messages = append(messages, newMessages.Messages...)
-
-			if len(newMessages.Messages) == 0 || len(messages) >= int(limit) {
-				break
-			}
-		}
-
-		c.sendMessagesReverse(chatID, messages)
 	// chat members
 	case "members":
 		var query string

telegram/handlers.go

@@ -153,6 +153,13 @@ func (c *Client) updateHandler() {
 
 // new user discovered
 func (c *Client) updateUser(update *client.UpdateUser) {
+	// check if MUC nicknames should be updated
+	cacheUser, ok := c.cache.GetUser(update.User.Id)
+	if ok && (cacheUser.FirstName != update.User.FirstName || cacheUser.LastName != update.User.LastName) {
+		newNickname := c.GetMUCNickname(update.User.Id)
+		c.updateMUCsNickname(update.User.Id, newNickname)
+	}
+
 	c.cache.SetUser(update.User.Id, update.User)
 	show, status, presenceType := c.userStatusToText(update.User.Status, update.User.Id)
 	go c.ProcessStatusUpdate(update.User.Id, status, show, gateway.SPType(presenceType))
@@ -265,7 +272,7 @@ func (c *Client) updateMessageContent(update *client.UpdateMessageContent) {
 			markupFunction,
 		))
 		for _, jid := range jids {
-			gateway.SendMessage(jid, strconv.FormatInt(update.ChatId, 10), text, "e"+strconv.FormatInt(update.MessageId, 10), c.xmpp, nil, false)
+			gateway.SendMessage(jid, strconv.FormatInt(update.ChatId, 10), text, "e"+strconv.FormatInt(update.MessageId, 10), c.xmpp, nil, 0, false, false, "")
 		}
 	}
 }
@@ -315,10 +322,14 @@ func (c *Client) updateMessageSendFailed(update *client.UpdateMessageSendFailed)
 
 // chat title changed
 func (c *Client) updateChatTitle(update *client.UpdateChatTitle) {
+	chat, user, _ := c.GetContactByID(update.ChatId, nil)
+	if c.Session.MUC && c.IsGroup(chat) {
+		return
+	}
+
 	gateway.SetNickname(c.jid, strconv.FormatInt(update.ChatId, 10), update.Title, c.xmpp)
 
 	// set also the status (for group chats only)
-	chat, user, _ := c.GetContactByID(update.ChatId, nil)
 	if user == nil {
 		c.ProcessStatusUpdate(update.ChatId, update.Title, "chat", gateway.SPImmed(true))
 	}

telegram/utils.go

@@ -44,6 +44,12 @@ var replyRegex = regexp.MustCompile("\\A>>? ?([0-9]+)\\n")
 const newlineChar string = "\n"
 const messageHeaderSeparator string = " | "
 
+const (
+	ChatTypeOther byte = iota
+	ChatTypePM
+	ChatTypeGroup
+)
+
 // GetContactByUsername resolves username to user id retrieves user and chat information
 func (c *Client) GetContactByUsername(username string) (*client.Chat, *client.User, error) {
 	if !c.Online() {
@@ -121,10 +127,10 @@ func (c *Client) GetContactByID(id int64, chat *client.Chat) (*client.Chat, *cli
 	return chat, user, nil
 }
 
-// IsPM checks if a chat is PM
+// GetChatType checks if a chat is PM or group
-func (c *Client) IsPM(id int64) (bool, error) {
+func (c *Client) GetChatType(id int64) (byte, error) {
 	if !c.Online() || id == 0 {
-		return false, errOffline
+		return ChatTypeOther, errOffline
 	}
 
 	var err error
@@ -135,7 +141,7 @@ func (c *Client) IsPM(id int64) (bool, error) {
 			ChatId: id,
 		})
 		if err != nil {
-			return false, err
+			return ChatTypeOther, err
 		}
 
 		c.cache.SetChat(id, chat)
@@ -143,9 +149,12 @@ func (c *Client) IsPM(id int64) (bool, error) {
 
 	chatType := chat.Type.ChatTypeType()
 	if chatType == client.TypeChatTypePrivate || chatType == client.TypeChatTypeSecret {
-		return true, nil
+		return ChatTypePM, nil
 	}
-	return false, nil
+	if c.IsGroup(chat) {
+		return ChatTypeGroup, nil
+	}
+	return ChatTypeOther, nil
 }
 
 func (c *Client) userStatusToText(status client.UserStatus, chatID int64) (string, string, string) {
@@ -217,6 +226,10 @@ func (c *Client) ProcessStatusUpdate(chatID int64, status string, show string, o
 		return err
 	}
 
+	if chat != nil && c.Session.MUC && c.IsGroup(chat) {
+		return nil
+	}
+
 	var photo string
 	if chat != nil && chat.Photo != nil {
 		file, path, err := c.ForceOpenFile(chat.Photo.Small, 1)
@@ -290,6 +303,214 @@ func (c *Client) ProcessStatusUpdate(chatID int64, status string, show string, o
 	)
 }
 
+// JoinMUC saves MUC join fact and sends initialization data
+func (c *Client) JoinMUC(chatId int64, resource string, limit int32) {
+	// save the nickname in this MUC, also as a marker of join
+	c.locks.mucCacheLock.Lock()
+	mucState, ok := c.mucCache[chatId]
+	if !ok || mucState == nil {
+		mucState = NewMUCState()
+		c.mucCache[chatId] = mucState
+	}
+	_, ok = mucState.Resources[resource]
+	if ok {
+		// already joined, initializing anyway
+	} else {
+		mucState.Resources[resource] = true
+	}
+	c.locks.mucCacheLock.Unlock()
+
+	c.sendMUCStatuses(chatId)
+
+	messages, err := c.getNLastMessages(chatId, limit)
+	if err == nil {
+		c.sendMessagesReverse(chatId, messages, false, c.jid+"/"+resource)
+	}
+
+	c.sendMUCSubject(chatId, resource)
+}
+
+func (c *Client) getFullName(user *client.User) string {
+	fullName := user.FirstName
+	if user.LastName != "" {
+		fullName = fullName + " " + user.LastName
+	}
+	return fullName
+}
+
+func (c *Client) sendMUCStatuses(chatID int64) {
+	c.locks.mucCacheLock.Lock()
+	defer c.locks.mucCacheLock.Unlock()
+	mucState, ok := c.mucCache[chatID]
+	if !ok || mucState == nil {
+		mucState = NewMUCState()
+		c.mucCache[chatID] = mucState
+	}
+
+	sChatId := strconv.FormatInt(chatID, 10)
+	myNickname := "me"
+	if c.me != nil {
+		myNickname = c.getFullName(c.me)
+	}
+	myAffiliation := "member"
+
+	members, err := c.client.SearchChatMembers(&client.SearchChatMembersRequest{
+		ChatId: chatID,
+		Limit:  200,
+		Filter: &client.ChatMembersFilterMembers{},
+	})
+	if err == nil {
+		gatewayJidSuffix := "@" + gateway.Jid.Full()
+
+		for _, member := range members.Members {
+			var senderId int64
+			switch member.MemberId.MessageSenderType() {
+			case client.TypeMessageSenderUser:
+				memberUser, _ := member.MemberId.(*client.MessageSenderUser)
+				senderId = memberUser.UserId
+			case client.TypeMessageSenderChat:
+				memberChat, _ := member.MemberId.(*client.MessageSenderChat)
+				senderId = memberChat.ChatId
+			}
+
+			nickname := c.GetMUCNickname(senderId)
+			affiliation := c.memberStatusToAffiliation(member.Status)
+			mucState.Members[senderId] = &MUCMember{
+				Nickname:    nickname,
+				Affiliation: affiliation,
+			}
+
+			if c.me != nil && senderId == c.me.Id {
+				myNickname = nickname
+				myAffiliation = affiliation
+				continue
+			}
+
+			gateway.SendPresence(
+				c.xmpp,
+				c.jid,
+				gateway.SPFrom(sChatId),
+				gateway.SPResource(nickname),
+				gateway.SPImmed(true),
+				gateway.SPMUCAffiliation(affiliation),
+				gateway.SPMUCJid(strconv.FormatInt(senderId, 10) + gatewayJidSuffix),
+			)
+		}
+	}
+
+	// according to the spec, own member entry should be sent the last
+	gateway.SendPresence(
+		c.xmpp,
+		c.jid,
+		gateway.SPFrom(sChatId),
+		gateway.SPResource(myNickname),
+		gateway.SPImmed(true),
+		gateway.SPMUCAffiliation(myAffiliation),
+		gateway.SPMUCStatusCodes([]uint16{100, 110, 210}),
+	)
+}
+
+func (c *Client) sendMUCSubject(chatID int64, resource string) {
+	pin, err := c.client.GetChatPinnedMessage(&client.GetChatPinnedMessageRequest{
+		ChatId: chatID,
+	})
+	mucJid := strconv.FormatInt(chatID, 10) + "@" + gateway.Jid.Bare()
+	toJid := c.jid + "/" + resource
+	if err == nil {
+		gateway.SendSubjectMessage(
+			toJid,
+			mucJid + "/" + c.GetMUCNickname(c.GetSenderId(pin)),
+			c.messageToText(pin, false),
+			strconv.FormatInt(pin.Id, 10),
+			c.xmpp,
+			int64(pin.Date),
+		)
+	} else {
+		gateway.SendSubjectMessage(toJid, mucJid, "", "", c.xmpp, 0)
+	}
+}
+
+// GetMUCNickname generates a unique nickname for a MUC member
+func (c *Client) GetMUCNickname(chatID int64) string {
+	return c.formatContact(chatID)
+}
+
+func (c *Client) updateMUCsNickname(memberID int64, newNickname string) {
+	c.locks.mucCacheLock.Lock()
+	defer c.locks.mucCacheLock.Unlock()
+
+	for mucId, state := range c.mucCache {
+		oldMember, ok := state.Members[memberID]
+		if ok {
+			state.Members[memberID] = &MUCMember{
+				Nickname:    newNickname,
+				Affiliation: oldMember.Affiliation,
+			}
+
+			sMucId := strconv.FormatInt(mucId, 10)
+			unavailableStatusCodes := []uint16{303, 210}
+			availableStatusCodes := []uint16{100, 210}
+			if c.me != nil && memberID == c.me.Id {
+				unavailableStatusCodes = append(unavailableStatusCodes, 110)
+				availableStatusCodes = append(availableStatusCodes, 110)
+			}
+			gateway.SendPresence(
+				c.xmpp,
+				c.jid,
+				gateway.SPType("unavailable"),
+				gateway.SPFrom(sMucId),
+				gateway.SPResource(oldMember.Nickname),
+				gateway.SPImmed(true),
+				gateway.SPMUCAffiliation(oldMember.Affiliation),
+				gateway.SPMUCNick(newNickname),
+				gateway.SPMUCStatusCodes(unavailableStatusCodes),
+			)
+			gateway.SendPresence(
+				c.xmpp,
+				c.jid,
+				gateway.SPFrom(sMucId),
+				gateway.SPResource(newNickname),
+				gateway.SPImmed(true),
+				gateway.SPMUCAffiliation(oldMember.Affiliation),
+				gateway.SPMUCStatusCodes(availableStatusCodes),
+			)
+		}
+	}
+}
+
+// MUCHasResource checks if a MUC was joined from a given resource
+func (c *Client) MUCHasResource(chatID int64, resource string) bool {
+	c.locks.mucCacheLock.Lock()
+	defer c.locks.mucCacheLock.Unlock()
+
+	mucState, ok := c.mucCache[chatID]
+	if !ok || mucState == nil {
+		return false
+	}
+	_, ok = mucState.Resources[resource]
+	return ok
+}
+
+// GetMyMUCNickname obtains this account's nickname in a given MUC
+func (c *Client) GetMyMUCNickname(chatID int64) (string, bool) {
+	if c.me == nil {
+		return "", false
+	}
+
+	c.locks.mucCacheLock.Lock()
+	defer c.locks.mucCacheLock.Unlock()
+
+	mucState, ok := c.mucCache[chatID]
+	if !ok || mucState == nil {
+		return "", false
+	}
+	member, ok := mucState.Members[c.me.Id]
+	if !ok {
+		return "", false
+	}
+	return member.Nickname, true
+}
+
 func (c *Client) formatContact(chatID int64) string {
 	if chatID == 0 {
 		return ""
@@ -322,7 +543,8 @@ func (c *Client) formatContact(chatID int64) string {
 	return str
 }
 
-func (c *Client) getSenderId(message *client.Message) (senderId int64) {
+// GetSenderId extracts a sender id from a message
+func (c *Client) GetSenderId(message *client.Message) (senderId int64) {
 	if message.SenderId != nil {
 		switch message.SenderId.MessageSenderType() {
 		case client.TypeMessageSenderUser:
@@ -338,7 +560,7 @@ func (c *Client) getSenderId(message *client.Message) (senderId int64) {
 }
 
 func (c *Client) formatSender(message *client.Message) string {
-	return c.formatContact(c.getSenderId(message))
+	return c.formatContact(c.GetSenderId(message))
 }
 
 func (c *Client) getMessageReply(message *client.Message) (reply *gateway.Reply, replyMsg *client.Message) {
@@ -358,7 +580,7 @@ func (c *Client) getMessageReply(message *client.Message) (reply *gateway.Reply,
 			replyId = strconv.FormatInt(message.ReplyToMessageId, 10)
 		}
 		reply = &gateway.Reply{
-			Author: fmt.Sprintf("%v@%s", c.getSenderId(replyMsg), gateway.Jid.Full()),
+			Author: fmt.Sprintf("%v@%s", c.GetSenderId(replyMsg), gateway.Jid.Full()),
 			Id:     replyId,
 		}
 	}
@@ -851,13 +1073,13 @@ func (c *Client) countCharsInLines(lines *[]string) (count int) {
 }
 
 func (c *Client) messageToPrefix(message *client.Message, previewString string, fileString string, replyMsg *client.Message) (string, int, int) {
-	isPM, err := c.IsPM(message.ChatId)
+	chatType, err := c.GetChatType(message.ChatId)
 	if err != nil {
-		log.Errorf("Could not determine if chat is PM: %v", err)
+		log.Errorf("Could not determine chat type: %v", err)
 	}
 	isCarbonsEnabled := gateway.MessageOutgoingPermissionVersion > 0 && c.Session.Carbons
 	// with carbons, hide for all messages in PM and only for outgoing in group chats
-	hideSender := isCarbonsEnabled && (message.IsOutgoing || isPM)
+	hideSender := (isCarbonsEnabled && (message.IsOutgoing || chatType == ChatTypePM)) || (c.Session.MUC && chatType == ChatTypeGroup)
 
 	var replyStart, replyEnd int
 	prefix := []string{}
@@ -878,7 +1100,7 @@ func (c *Client) messageToPrefix(message *client.Message, previewString string,
 			}
 		}
 	}
-	if !isPM || !c.Session.HideIds {
+	if (chatType != ChatTypePM && !c.Session.MUC) || !c.Session.HideIds {
 		prefix = append(prefix, directionChar+strconv.FormatInt(message.Id, 10))
 	}
 	// show sender in group chats
@@ -931,10 +1153,29 @@ func (c *Client) ensureDownloadFile(file *client.File) *client.File {
 	return file
 }
 
-// ProcessIncomingMessage transfers a message to XMPP side and marks it as read on Telegram side
+// ProcessIncomingMessage is a legacy wrapper for SendMessageToGateway aiming only PM messages
 func (c *Client) ProcessIncomingMessage(chatId int64, message *client.Message) {
-	isCarbon := gateway.MessageOutgoingPermissionVersion > 0 && c.Session.Carbons && message.IsOutgoing
+	c.SendMessageToGateway(chatId, message, "", false, "", []string{})
-	jids := c.getCarbonFullJids(isCarbon, "")
+}
+
+// SendMessageToGateway transfers a message to XMPP side and marks it as read on Telegram side
+func (c *Client) SendMessageToGateway(chatId int64, message *client.Message, id string, delay bool, groupChatFrom string, groupChatTos []string) {
+	var isCarbon bool
+	var jids []string
+	var isGroupchat bool
+	var originalFrom string
+	if len(groupChatTos) == 0 {
+		isCarbon = gateway.MessageOutgoingPermissionVersion > 0 && c.Session.Carbons && message.IsOutgoing
+		jids = c.getCarbonFullJids(isCarbon, "")
+	} else {
+		isGroupchat = true
+		jids = groupChatTos
+
+		senderId := c.GetSenderId(message)
+		if senderId != 0 {
+			originalFrom = strconv.FormatInt(senderId, 10) + "@" + gateway.Jid.Full()
+		}
+	}
 
 	var text, oob, auxText string
 
@@ -1006,13 +1247,29 @@ func (c *Client) ProcessIncomingMessage(chatId int64, message *client.Message) {
 	})
 
 	// forward message to XMPP
-	sId := strconv.FormatInt(message.Id, 10)
+	var sId string
-	sChatId := strconv.FormatInt(chatId, 10)
+	if id == "" {
+		sId = strconv.FormatInt(message.Id, 10)
+	} else {
+		sId = id
+	}
+
+	var from string
+	if groupChatFrom == "" {
+		from = strconv.FormatInt(chatId, 10)
+	} else {
+		from = groupChatFrom
+	}
+
+	var timestamp int64
+	if delay {
+		timestamp = int64(message.Date)
+	}
 
 	for _, jid := range jids {
-		gateway.SendMessageWithOOB(jid, sChatId, text, sId, c.xmpp, reply, oob, isCarbon)
+		gateway.SendMessageWithOOB(jid, from, text, sId, c.xmpp, reply, timestamp, oob, isCarbon, isGroupchat, originalFrom)
 		if auxText != "" {
-			gateway.SendMessage(jid, sChatId, auxText, sId, c.xmpp, reply, isCarbon)
+			gateway.SendMessage(jid, from, auxText, sId, c.xmpp, reply, timestamp, isCarbon, isGroupchat, originalFrom)
 		}
 	}
 }
@@ -1023,21 +1280,21 @@ func (c *Client) PrepareOutgoingMessageContent(text string) client.InputMessageC
 }
 
 // ProcessOutgoingMessage executes commands or sends messages to mapped chats, returns message id
-func (c *Client) ProcessOutgoingMessage(chatID int64, text string, returnJid string, replyId int64, replaceId int64) int64 {
+func (c *Client) ProcessOutgoingMessage(chatID int64, text string, returnJid string, replyId int64, replaceId int64, isGroupchat bool) *client.Message {
 	if !c.Online() {
 		// we're offline
-		return 0
+		return nil
 	}
 
 	if replaceId == 0 && (strings.HasPrefix(text, "/") || strings.HasPrefix(text, "!")) {
 		// try to execute commands
 		response, isCommand := c.ProcessChatCommand(chatID, text)
 		if response != "" {
-			c.returnMessage(returnJid, chatID, response)
+			c.returnMessage(returnJid, chatID, response, 0, isGroupchat)
 		}
 		// do not send on success
 		if isCommand {
-			return 0
+			return nil
 		}
 	}
 
@@ -1059,27 +1316,31 @@ func (c *Client) ProcessOutgoingMessage(chatID int64, text string, returnJid str
 	if c.content.Upload != "" && strings.HasPrefix(text, c.content.Upload) {
 		response, err := http.Get(text)
 		if err != nil {
-			c.returnError(returnJid, chatID, "Failed to fetch the uploaded file", err)
+			c.returnError(returnJid, chatID, "Failed to fetch the uploaded file", err, 500, isGroupchat)
 		}
 		if response != nil && response.Body != nil {
 			defer response.Body.Close()
 
 			if response.StatusCode != 200 {
-				c.returnMessage(returnJid, chatID, fmt.Sprintf("Received status code %v", response.StatusCode))
+				c.returnMessage(returnJid, chatID, fmt.Sprintf("Received status code %v", response.StatusCode), response.StatusCode, isGroupchat)
+				return nil
 			}
 
 			tempDir, err := ioutil.TempDir("", "telegabber-*")
 			if err != nil {
-				c.returnError(returnJid, chatID, "Failed to create a temporary directory", err)
+				c.returnError(returnJid, chatID, "Failed to create a temporary directory", err, 500, isGroupchat)
+				return nil
 			}
 			tempFile, err := os.Create(filepath.Join(tempDir, filepath.Base(text)))
 			if err != nil {
-				c.returnError(returnJid, chatID, "Failed to create a temporary file", err)
+				c.returnError(returnJid, chatID, "Failed to create a temporary file", err, 500, isGroupchat)
+				return nil
 			}
 
 			_, err = io.Copy(tempFile, response.Body)
 			if err != nil {
-				c.returnError(returnJid, chatID, "Failed to write a temporary file", err)
+				c.returnError(returnJid, chatID, "Failed to write a temporary file", err, 500, isGroupchat)
+				return nil
 			}
 
 			file = &client.InputFileLocal{
@@ -1107,10 +1368,10 @@ func (c *Client) ProcessOutgoingMessage(chatID int64, text string, returnJid str
 			InputMessageContent: content,
 		})
 		if err != nil {
-			c.returnError(returnJid, chatID, "Not edited", err)
+			c.returnError(returnJid, chatID, "Not edited", err, 400, isGroupchat)
-			return 0
+			return nil
 		}
-		return tgMessage.Id
+		return tgMessage
 	}
 
 	tgMessage, err := c.client.SendMessage(&client.SendMessageRequest{
@@ -1119,18 +1380,30 @@ func (c *Client) ProcessOutgoingMessage(chatID int64, text string, returnJid str
 		InputMessageContent: content,
 	})
 	if err != nil {
-		c.returnError(returnJid, chatID, "Not sent", err)
+		c.returnError(returnJid, chatID, "Not sent", err, 400, isGroupchat)
-		return 0
+		return nil
 	}
-	return tgMessage.Id
+	return tgMessage
 }
 
-func (c *Client) returnMessage(returnJid string, chatID int64, text string) {
+func (c *Client) returnMessage(returnJid string, chatID int64, text string, code int, isGroupchat bool) {
-	gateway.SendTextMessage(returnJid, strconv.FormatInt(chatID, 10), text, c.xmpp)
+	sChatId := strconv.FormatInt(chatID, 10)
+	if isGroupchat {
+		gateway.SendErrorMessage(returnJid, sChatId + "@" + gateway.Jid.Bare(), text, code, isGroupchat, c.xmpp)
+	} else {
+		gateway.SendTextMessage(returnJid, sChatId, text, c.xmpp)
+	}
 }
 
-func (c *Client) returnError(returnJid string, chatID int64, msg string, err error) {
+func (c *Client) returnError(returnJid string, chatID int64, msg string, err error, code int, isGroupchat bool) {
-	c.returnMessage(returnJid, chatID, fmt.Sprintf("%s: %s", msg, err.Error()))
+	responseError, ok := err.(client.ResponseError)
+	log.Debugf("responseError: %#v", responseError)
+	if ok && responseError.Err != nil {
+		if responseError.Err.Message == "Have no write access to the chat" {
+			code = 403
+		}
+	}
+	c.returnMessage(returnJid, chatID, fmt.Sprintf("%s: %s", msg, err.Error()), code, isGroupchat)
 }
 
 func (c *Client) prepareOutgoingMessageContent(text string, file *client.InputFileLocal) client.InputMessageContent {
@@ -1228,6 +1501,36 @@ func (c *Client) getLastMessages(id int64, query string, from int64, count int32
 	})
 }
 
+func (c *Client) getNLastMessages(chatID int64, limit int32) ([]*client.Message, error) {
+	var newMessages *client.Messages
+	var messages []*client.Message
+	var err error
+	var fromId int64
+
+	for _ = range make([]struct{}, limit) { // safety limit
+		if len(messages) > 0 {
+			fromId = messages[len(messages)-1].Id
+		}
+
+		newMessages, err = c.client.GetChatHistory(&client.GetChatHistoryRequest{
+			ChatId:        chatID,
+			FromMessageId: fromId,
+			Limit:         limit,
+		})
+		if err != nil {
+			return nil, err
+		}
+
+		messages = append(messages, newMessages.Messages...)
+
+		if len(newMessages.Messages) == 0 || len(messages) >= int(limit) {
+			break
+		}
+	}
+
+	return messages, nil
+}
+
 // DownloadFile actually obtains a file by id given by TDlib
 func (c *Client) DownloadFile(id int32, priority int32, synchronous bool) (*client.File, error) {
 	return c.client.DownloadFile(&client.DownloadFileRequest{
@@ -1285,7 +1588,7 @@ func (c *Client) GetChatDescription(chat *client.Chat) string {
 				}
 			}
 		} else {
-			log.Warnf("Coudln't retrieve private chat info: %v", err.Error())
+			log.Warnf("Couldn't retrieve private chat info: %v", err.Error())
 		}
 	} else if chatType == client.TypeChatTypeBasicGroup {
 		basicGroupType, _ := chat.Type.(*client.ChatTypeBasicGroup)
@@ -1295,7 +1598,7 @@ func (c *Client) GetChatDescription(chat *client.Chat) string {
 		if err == nil {
 			return fullInfo.Description
 		} else {
-			log.Warnf("Coudln't retrieve basic group info: %v", err.Error())
+			log.Warnf("Couldn't retrieve basic group info: %v", err.Error())
 		}
 	} else if chatType == client.TypeChatTypeSupergroup {
 		supergroupType, _ := chat.Type.(*client.ChatTypeSupergroup)
@@ -1305,12 +1608,68 @@ func (c *Client) GetChatDescription(chat *client.Chat) string {
 		if err == nil {
 			return fullInfo.Description
 		} else {
-			log.Warnf("Coudln't retrieve supergroup info: %v", err.Error())
+			log.Warnf("Couldn't retrieve supergroup info: %v", err.Error())
 		}
 	}
 	return ""
 }
 
+// GetChatMemberCount obtains the member count depending on the chat type
+func (c *Client) GetChatMemberCount(chat *client.Chat) int32 {
+	chatType := chat.Type.ChatTypeType()
+	if chatType == client.TypeChatTypePrivate {
+		return 2
+	} else if chatType == client.TypeChatTypeBasicGroup {
+		basicGroupType, _ := chat.Type.(*client.ChatTypeBasicGroup)
+		basicGroup, err := c.client.GetBasicGroup(&client.GetBasicGroupRequest{
+			BasicGroupId: basicGroupType.BasicGroupId,
+		})
+		if err == nil {
+			return basicGroup.MemberCount
+		} else {
+			log.Warnf("Couldn't retrieve basic group: %v", err.Error())
+		}
+	} else if chatType == client.TypeChatTypeSupergroup {
+		supergroupType, _ := chat.Type.(*client.ChatTypeSupergroup)
+		supergroup, err := c.client.GetSupergroup(&client.GetSupergroupRequest{
+			SupergroupId: supergroupType.SupergroupId,
+		})
+		if err == nil {
+			return supergroup.MemberCount
+		} else {
+			log.Warnf("Couldn't retrieve supergroup: %v", err.Error())
+		}
+	}
+	return 0
+}
+
+// GetGroupChats obtains all group chats
+func (c *Client) GetGroupChats() []*client.Chat {
+	var groupChats []*client.Chat
+
+	chats, err := c.client.GetChats(&client.GetChatsRequest{
+		Limit: chatsLimit,
+	})
+	if err == nil {
+		for _, id := range chats.ChatIds {
+			chat, _, _ := c.GetContactByID(id, nil)
+			if chat != nil && c.IsGroup(chat) {
+				groupChats = append(groupChats, chat)
+			}
+		}
+	} else {
+		log.Errorf("Could not retrieve chats: %v", err)
+	}
+
+	return groupChats
+}
+
+// IsGroup determines if a chat is eligible to be represented as MUC
+func (c *Client) IsGroup(chat *client.Chat) bool {
+	typ := chat.Type.ChatTypeType()
+	return typ == client.TypeChatTypeBasicGroup
+}
+
 // subscribe to a Telegram ID
 func (c *Client) subscribeToID(id int64, chat *client.Chat) {
 	var args []args.V
@@ -1321,6 +1680,10 @@ func (c *Client) subscribeToID(id int64, chat *client.Chat) {
 		chat, _, _ = c.GetContactByID(id, nil)
 	}
 	if chat != nil {
+		if c.Session.MUC && c.IsGroup(chat) {
+			return
+		}
+
 		args = append(args, gateway.SPNickname(chat.Title))
 
 		gateway.SetNickname(c.jid, strconv.FormatInt(id, 10), chat.Title, c.xmpp)
@@ -1378,6 +1741,10 @@ func (c *Client) UpdateChatNicknames() {
 	for _, id := range c.cache.ChatsKeys() {
 		chat, ok := c.cache.GetChat(id)
 		if ok {
+			if c.Session.MUC && c.IsGroup(chat) {
+				continue
+			}
+
 			newArgs := []args.V{
 				gateway.SPFrom(strconv.FormatInt(id, 10)),
 				gateway.SPNickname(chat.Title),
@@ -1504,3 +1871,59 @@ func (c *Client) usernamesToString(usernames []string) string {
 	}
 	return strings.Join(atUsernames, ", ")
 }
+
+func (c *Client) memberStatusToAffiliation(memberStatus client.ChatMemberStatus) string {
+	switch memberStatus.ChatMemberStatusType() {
+	case client.TypeChatMemberStatusCreator:
+		return "owner"
+	case client.TypeChatMemberStatusAdministrator:
+		return "admin"
+	case client.TypeChatMemberStatusMember:
+		return "member"
+	case client.TypeChatMemberStatusRestricted:
+		return "outcast"
+	case client.TypeChatMemberStatusLeft:
+		return "none"
+	case client.TypeChatMemberStatusBanned:
+		return "outcast"
+	}
+	return "member"
+}
+
+func (c *Client) sendMessagesReverse(chatID int64, messages []*client.Message, plain bool, toJid string) {
+	sChatId := strconv.FormatInt(chatID, 10)
+	var mucJid string
+	if toJid != "" {
+		mucJid = sChatId + "@" + gateway.Jid.Bare()
+	}
+
+	for i := len(messages) - 1; i >= 0; i-- {
+		message := messages[i]
+
+		if plain {
+			reply, _ := c.getMessageReply(message)
+
+			gateway.SendMessage(
+				c.jid,
+				sChatId,
+				c.formatMessage(0, 0, false, message),
+				strconv.FormatInt(message.Id, 10),
+				c.xmpp,
+				reply,
+				0,
+				false,
+				false,
+				"",
+			)
+		} else {
+			c.SendMessageToGateway(
+				chatID,
+				message,
+				"",
+				true,
+				mucJid + "/" + c.GetMUCNickname(c.GetSenderId(message)),
+				[]string{toJid},
+			)
+		}
+	}
+}

xmpp/extensions/extensions.go

@@ -213,6 +213,60 @@ type QueryRegisterRemove struct {
 	XMLName xml.Name `xml:"remove"`
 }
 
+// PresenceXMucUserExtension is from XEP-0045
+type PresenceXMucUserExtension struct {
+	XMLName  xml.Name               `xml:"http://jabber.org/protocol/muc#user x"`
+	Item     PresenceXMucUserItem
+	Statuses []PresenceXMucUserStatus
+}
+
+// PresenceXMucUserItem is from XEP-0045
+type PresenceXMucUserItem struct {
+	XMLName     xml.Name `xml:"item"`
+	Affiliation	string   `xml:"affiliation,attr"`
+	Jid         string   `xml:"jid,attr"`
+	Nick        string   `xml:"nick,attr,omitempty"`
+	Role       	string   `xml:"role,attr"`
+}
+
+// PresenceXMucUserStatus is from XEP-0045
+type PresenceXMucUserStatus struct {
+	XMLName xml.Name `xml:"status"`
+	Code    uint16   `xml:"code,attr"`
+}
+
+// MessageDelay is from XEP-0203
+type MessageDelay struct {
+	XMLName xml.Name `xml:"urn:xmpp:delay delay"`
+	From    string   `xml:"from,attr"`
+	Stamp   string   `xml:"stamp,attr"`
+}
+
+// MessageDelayLegacy is from XEP-0203
+type MessageDelayLegacy struct {
+	XMLName xml.Name `xml:"jabber:x:delay x"`
+	From    string   `xml:"from,attr"`
+	Stamp   string   `xml:"stamp,attr"`
+}
+
+// MessageAddresses is from XEP-0033
+type MessageAddresses struct {
+	XMLName   xml.Name  `xml:"http://jabber.org/protocol/address addresses"`
+	Addresses []MessageAddress
+}
+
+// MessageAddress is from XEP-0033
+type MessageAddress struct {
+	XMLName xml.Name `xml:"address"`
+	Type    string   `xml:"type,attr"`
+	Jid     string   `xml:"jid,attr"`
+}
+
+// EmptySubject is a dummy for MUCs to circumvent omitempty. Not registered as it would conflict with Subject field
+type EmptySubject struct {
+	XMLName xml.Name `xml:"subject"`
+}
+
 // Namespace is a namespace!
 func (c PresenceNickExtension) Namespace() string {
 	return c.XMLName.Space
@@ -278,6 +332,21 @@ func (c QueryRegister) GetSet() *stanza.ResultSet {
 	return c.ResultSet
 }
 
+// Namespace is a namespace!
+func (c PresenceXMucUserExtension) Namespace() string {
+	return c.XMLName.Space
+}
+
+// Namespace is a namespace!
+func (c MessageDelay) Namespace() string {
+	return c.XMLName.Space
+}
+
+// Namespace is a namespace!
+func (c MessageDelayLegacy) Namespace() string {
+	return c.XMLName.Space
+}
+
 // Name is a packet name
 func (ClientMessage) Name() string {
 	return "message"
@@ -362,4 +431,28 @@ func init() {
 		"jabber:iq:register",
 		"query",
 	}, QueryRegister{})
+
+	// presence muc user
+	stanza.TypeRegistry.MapExtension(stanza.PKTPresence, xml.Name{
+		"http://jabber.org/protocol/muc#user",
+		"x",
+	}, PresenceXMucUserExtension{})
+
+	// message delay
+	stanza.TypeRegistry.MapExtension(stanza.PKTMessage, xml.Name{
+		"urn:xmpp:delay",
+		"delay",
+	}, MessageDelay{})
+
+	// legacy message delay
+	stanza.TypeRegistry.MapExtension(stanza.PKTMessage, xml.Name{
+		"jabber:x:delay",
+		"x",
+	}, MessageDelayLegacy{})
+
+	// message addresses
+	stanza.TypeRegistry.MapExtension(stanza.PKTMessage, xml.Name{
+		"http://jabber.org/protocol/address",
+		"addresses",
+	}, MessageAddresses{})
 }

xmpp/gateway/gateway.go

@@ -5,6 +5,7 @@ import (
 	"github.com/pkg/errors"
 	"strings"
 	"sync"
+	"time"
 
 	"dev.narayana.im/narayana/telegabber/badger"
 	"dev.narayana.im/narayana/telegabber/xmpp/extensions"
@@ -42,26 +43,41 @@ var DirtySessions = false
 var MessageOutgoingPermissionVersion = 0
 
 // SendMessage creates and sends a message stanza
-func SendMessage(to string, from string, body string, id string, component *xmpp.Component, reply *Reply, isCarbon bool) {
+func SendMessage(to, from, body, id string, component *xmpp.Component, reply *Reply, timestamp int64, isCarbon, isGroupchat bool, originalFrom string) {
-	sendMessageWrapper(to, from, body, id, component, reply, "", isCarbon)
+	sendMessageWrapper(to, from, body, "", "", id, component, reply, timestamp, "", isCarbon, isGroupchat, false, originalFrom, 0)
 }
 
 // SendServiceMessage creates and sends a simple message stanza from transport
-func SendServiceMessage(to string, body string, component *xmpp.Component) {
+func SendServiceMessage(to, body string, component *xmpp.Component) {
-	sendMessageWrapper(to, "", body, "", component, nil, "", false)
+	sendMessageWrapper(to, "", body, "", "", "", component, nil, 0, "", false, false, false, "", 0)
 }
 
 // SendTextMessage creates and sends a simple message stanza
-func SendTextMessage(to string, from string, body string, component *xmpp.Component) {
+func SendTextMessage(to, from, body string, component *xmpp.Component) {
-	sendMessageWrapper(to, from, body, "", component, nil, "", false)
+	sendMessageWrapper(to, from, body, "", "", "", component, nil, 0, "", false, false, false, "", 0)
+}
+
+// SendErrorMessage creates and sends an error message stanza
+func SendErrorMessage(to, from, text string, code int, isGroupchat bool, component *xmpp.Component) {
+	sendMessageWrapper(to, from, "", "", text, "", component, nil, 0, "", false, isGroupchat, false, "", code)
+}
+
+// SendErrorMessageWithBody creates and sends an error message stanza with body payload
+func SendErrorMessageWithBody(to, from, body, errorText, id string, code int, isGroupchat bool, component *xmpp.Component) {
+	sendMessageWrapper(to, from, body, "", errorText, id, component, nil, 0, "", false, isGroupchat, false, "", code)
 }
 
 // SendMessageWithOOB creates and sends a message stanza with OOB URL
-func SendMessageWithOOB(to string, from string, body string, id string, component *xmpp.Component, reply *Reply, oob string, isCarbon bool) {
+func SendMessageWithOOB(to, from, body, id string, component *xmpp.Component, reply *Reply, timestamp int64, oob string, isCarbon, isGroupchat bool, originalFrom string) {
-	sendMessageWrapper(to, from, body, id, component, reply, oob, isCarbon)
+	sendMessageWrapper(to, from, body, "", "", id, component, reply, timestamp, oob, isCarbon, isGroupchat, false, originalFrom, 0)
 }
 
-func sendMessageWrapper(to string, from string, body string, id string, component *xmpp.Component, reply *Reply, oob string, isCarbon bool) {
+// SendSubjectMessage creates and sends a MUC subject
+func SendSubjectMessage(to, from, subject, id string, component *xmpp.Component, timestamp int64) {
+	sendMessageWrapper(to, from, "", subject, "", id, component, nil, timestamp, "", false, true, true, "", 0)
+}
+
+func sendMessageWrapper(to, from, body, subject, errorText, id string, component *xmpp.Component, reply *Reply, timestamp int64, oob string, isCarbon, isGroupchat, forceSubject bool, originalFrom string, errorCode int) {
 	toJid, err := stanza.NewJid(to)
 	if err != nil {
 		log.WithFields(log.Fields{
@@ -76,6 +92,10 @@ func sendMessageWrapper(to string, from string, body string, id string, componen
 	var logFrom string
 	var messageFrom string
 	var messageTo string
+	if isGroupchat {
+		logFrom = from
+		messageFrom = from
+	} else {
 		if from == "" {
 			logFrom = componentJid
 			messageFrom = componentJid
@@ -83,6 +103,7 @@ func sendMessageWrapper(to string, from string, body string, id string, componen
 			logFrom = from
 			messageFrom = from + "@" + componentJid
 		}
+	}
 	if isCarbon {
 		messageTo = messageFrom
 		messageFrom = bareTo + "/" + Jid.Resource
@@ -95,15 +116,52 @@ func sendMessageWrapper(to string, from string, body string, id string, componen
 		"to":   to,
 	}).Warn("Got message")
 
+	var messageType stanza.StanzaType
+	if errorCode != 0 {
+		messageType = stanza.MessageTypeError
+	} else if isGroupchat {
+		messageType = stanza.MessageTypeGroupchat
+	} else {
+		messageType = stanza.MessageTypeChat
+	}
+
 	message := stanza.Message{
 		Attrs: stanza.Attrs{
 			From: messageFrom,
 			To:   messageTo,
-			Type: "chat",
+			Type: messageType,
 			Id:   id,
 		},
+		Subject: subject,
 		Body:    body,
 	}
+	if errorCode != 0 {
+		message.Error = stanza.Err{
+			Code: errorCode,
+			Text: errorText,
+		}
+		switch errorCode {
+		case 400:
+			message.Error.Type = stanza.ErrorTypeModify
+			message.Error.Reason = "bad-request"
+		case 403:
+			message.Error.Type = stanza.ErrorTypeAuth
+			message.Error.Reason = "forbidden"
+		case 404:
+			message.Error.Type = stanza.ErrorTypeCancel
+			message.Error.Reason = "item-not-found"
+		case 406:
+			message.Error.Type = stanza.ErrorTypeModify
+			message.Error.Reason = "not-acceptable"
+		case 500:
+			message.Error.Type = stanza.ErrorTypeWait
+			message.Error.Reason = "internal-server-error"
+		default:
+			log.Error("Unknown error code, falling back with empty reason")
+			message.Error.Type = stanza.ErrorTypeCancel
+			message.Error.Reason = "undefined-condition"
+		}
+	}
 
 	if oob != "" {
 		message.Extensions = append(message.Extensions, stanza.OOB{
@@ -119,16 +177,43 @@ func sendMessageWrapper(to string, from string, body string, id string, componen
 			message.Extensions = append(message.Extensions, extensions.NewReplyFallback(reply.Start, reply.End))
 		}
 	}
-	if !isCarbon && toJid.Resource != "" {
+	if !isGroupchat && !isCarbon && toJid.Resource != "" {
 		message.Extensions = append(message.Extensions, stanza.HintNoCopy{})
 	}
+	if timestamp != 0 {
+		var delayFrom string
+		if isGroupchat {
+			delayFrom, _, _ = SplitJID(from)
+		}
+		message.Extensions = append(message.Extensions, extensions.MessageDelay{
+			From:  delayFrom,
+			Stamp: time.Unix(timestamp, 0).UTC().Format(time.RFC3339),
+		})
+		message.Extensions = append(message.Extensions, extensions.MessageDelayLegacy{
+			From:  delayFrom,
+			Stamp: time.Unix(timestamp, 0).UTC().Format("20060102T15:04:05"),
+		})
+	}
+	if originalFrom != "" {
+		message.Extensions = append(message.Extensions, extensions.MessageAddresses{
+			Addresses: []extensions.MessageAddress{
+				extensions.MessageAddress{
+					Type: "ofrom",
+					Jid:  originalFrom,
+				},
+			},
+		})
+	}
+	if subject == "" && forceSubject {
+		message.Extensions = append(message.Extensions, extensions.EmptySubject{})
+	}
 
 	if isCarbon {
 		carbonMessage := extensions.ClientMessage{
 			Attrs: stanza.Attrs{
 				From: bareTo,
 				To:   to,
-				Type: "chat",
+				Type: messageType,
 			},
 		}
 		carbonMessage.Extensions = append(carbonMessage.Extensions, extensions.CarbonSent{
@@ -240,6 +325,18 @@ var SPResource = args.NewString()
 // SPImmed skips queueing
 var SPImmed = args.NewBool(args.Default(true))
 
+// SPMUCAffiliation is a XEP-0045 MUC affiliation
+var SPMUCAffiliation = args.NewString()
+
+// SPMUCNick is a XEP-0045 MUC user nick
+var SPMUCNick = args.NewString()
+
+// SPMUCJid is a real jid of a MUC member
+var SPMUCJid = args.NewString()
+
+// SPMUCStatusCodes is a set of XEP-0045 MUC status codes
+var SPMUCStatusCodes = args.New()
+
 func newPresence(bareJid string, to string, args ...args.V) stanza.Presence {
 	var presenceFrom string
 	if SPFrom.IsSet(args) {
@@ -295,6 +392,32 @@ func newPresence(bareJid string, to string, args ...args.V) stanza.Presence {
 			})
 		}
 	}
+	if SPMUCAffiliation.IsSet(args) {
+		affiliation := SPMUCAffiliation.Get(args)
+		if affiliation != "" {
+			userExt := extensions.PresenceXMucUserExtension{
+				Item: extensions.PresenceXMucUserItem{
+					Affiliation: affiliation,
+					Role:        affilationToRole(affiliation),
+				},
+			}
+			if SPMUCNick.IsSet(args) {
+				userExt.Item.Nick = SPMUCNick.Get(args)
+			}
+			if SPMUCJid.IsSet(args) {
+				userExt.Item.Jid = SPMUCJid.Get(args)
+			}
+			if SPMUCStatusCodes.IsSet(args) {
+				statusCodes := SPMUCStatusCodes.Get(args).([]uint16)
+				for _, statusCode := range statusCodes {
+					userExt.Statuses = append(userExt.Statuses, extensions.PresenceXMucUserStatus{
+						Code: statusCode,
+					})
+				}
+			}
+			presence.Extensions = append(presence.Extensions, userExt)
+		}
+	}
 
 	return presence
 }
@@ -377,3 +500,13 @@ func SplitJID(from string) (string, string, bool) {
 	}
 	return fromJid.Bare(), fromJid.Resource, true
 }
+
+func affilationToRole(affilation string) string {
+	switch affilation {
+	case "owner", "admin":
+		return "moderator"
+	case "member":
+		return "participant"
+	}
+	return "none"
+}

xmpp/handlers.go

@@ -27,6 +27,12 @@ const (
 )
 const NodeVCard4 string = "urn:xmpp:vcard4"
 
+type discoType int
+const (
+	discoTypeInfo discoType = iota
+	discoTypeItems
+)
+
 func logPacketType(p stanza.Packet) {
 	log.Warnf("Ignoring packet: %T\n", p)
 }
@@ -55,12 +61,12 @@ func HandleIq(s xmpp.Sender, p stanza.Packet) {
 		}
 		_, ok = iq.Payload.(*stanza.DiscoInfo)
 		if ok {
-			go handleGetDiscoInfo(s, iq)
+			go handleGetDisco(discoTypeInfo, s, iq)
 			return
 		}
 		_, ok = iq.Payload.(*stanza.DiscoItems)
 		if ok {
-			go handleGetDiscoItems(s, iq)
+			go handleGetDisco(discoTypeItems, s, iq)
 			return
 		}
 		_, ok = iq.Payload.(*extensions.QueryRegister)
@@ -117,6 +123,26 @@ func HandleMessage(s xmpp.Sender, p stanza.Packet) {
 
 		toID, ok := toToID(msg.To)
 		if ok {
+			toJid, err := stanza.NewJid(msg.To)
+			if err != nil {
+				log.Error("Invalid to JID!")
+				return
+			}
+
+			isGroupchat := msg.Type == "groupchat"
+
+			if session.Session.MUC && toJid.Resource != "" {
+				chat, _, err := session.GetContactByID(toID, nil)
+				if err == nil && session.IsGroup(chat) {
+					if isGroupchat {
+						gateway.SendErrorMessageWithBody(msg.From, msg.To, msg.Body, "", msg.Id, 400, true, component)
+					} else {
+						gateway.SendErrorMessage(msg.From, msg.To, "PMing room members is not supported, use the real JID", 406, true, component)
+					}
+					return
+				}
+			}
+
 			var reply extensions.Reply
 			var fallback extensions.Fallback
 			var replace extensions.Replace
@@ -128,7 +154,6 @@ func HandleMessage(s xmpp.Sender, p stanza.Packet) {
 			log.Debugf("replace: %#v", replace)
 
 			var replyId int64
-			var err error
 			text := msg.Body
 			if len(reply.Id) > 0 {
 				chatId, msgId, err := gateway.IdsDB.GetByXmppId(session.Session.Login, bare, reply.Id)
@@ -191,8 +216,8 @@ func HandleMessage(s xmpp.Sender, p stanza.Packet) {
 
 			session.SendMessageLock.Lock()
 			defer session.SendMessageLock.Unlock()
-			tgMessageId := session.ProcessOutgoingMessage(toID, text, msg.From, replyId, replaceId)
+			tgMessage := session.ProcessOutgoingMessage(toID, text, msg.From, replyId, replaceId, isGroupchat)
-			if tgMessageId != 0 {
+			if tgMessage != nil {
 				if replaceId != 0 {
 					// not needed (is it persistent among clients though?)
 					/* err = gateway.IdsDB.ReplaceIdPair(session.Session.Login, bare, replace.Id, msg.Id, tgMessageId)
@@ -201,11 +226,23 @@ func HandleMessage(s xmpp.Sender, p stanza.Packet) {
 					} */
 					session.AddToOutbox(replace.Id, resource)
 				} else {
-					err = gateway.IdsDB.Set(session.Session.Login, bare, toID, tgMessageId, msg.Id)
+					err = gateway.IdsDB.Set(session.Session.Login, bare, toID, tgMessage.Id, msg.Id)
 					if err != nil {
-						log.Errorf("Failed to save ids %v/%v %v", toID, tgMessageId, msg.Id)
+						log.Errorf("Failed to save ids %v/%v %v", toID, tgMessage.Id, msg.Id)
 					}
 				}
+
+				// pong groupchat messages back
+				if isGroupchat && toJid.Resource == "" {
+					session.SendMessageToGateway(
+						toID,
+						tgMessage,
+						msg.Id,
+						false,
+						msg.To + "/" + session.GetMUCNickname(session.GetSenderId(tgMessage)),
+						[]string{msg.From},
+					)
+				}
 			} else {
 				/*
 					// if a message failed to edit on Telegram side, match new XMPP ID with old Telegram ID anyway
@@ -281,7 +318,15 @@ func HandlePresence(s xmpp.Sender, p stanza.Packet) {
 	}
 	if prs.To == gateway.Jid.Bare() {
 		handlePresence(s, prs)
+		return
 	}
+	var mucExt stanza.MucPresence
+	prs.Get(&mucExt)
+	if mucExt.XMLName.Space != "" {
+		handleMUCPresence(s, prs, mucExt)
+		return
+	}
+	tryHandleMUCNicknameChange(s, prs)
 }
 
 func handleSubscription(s xmpp.Sender, p stanza.Presence) {
@@ -391,6 +436,141 @@ func handlePresence(s xmpp.Sender, p stanza.Presence) {
 	}
 }
 
+func handleMUCPresence(s xmpp.Sender, p stanza.Presence, mucExt stanza.MucPresence) {
+	log.WithFields(log.Fields{
+		"type": p.Type,
+		"from": p.From,
+		"to":   p.To,
+	}).Warn("MUC presence")
+	log.Debugf("%#v", p)
+
+	if p.Type == "" {
+		toBare, nickname, ok := gateway.SplitJID(p.To)
+		if ok {
+			component, ok := s.(*xmpp.Component)
+			if !ok {
+				log.Error("Not a component")
+				return
+			}
+
+			// separate declaration is crucial for passing as pointer to defer
+			var reply *stanza.Presence
+			reply = &stanza.Presence{Attrs: stanza.Attrs{
+				From: toBare,
+				To:   p.From,
+				Id:   p.Id,
+			}}
+			defer gateway.ResumableSend(component, reply)
+
+			if nickname == "" {
+				presenceReplySetError(reply, 400)
+				return
+			}
+
+			chatId, ok := toToID(toBare)
+			if !ok {
+				presenceReplySetError(reply, 404)
+				return
+			}
+
+			fromBare, fromResource, ok := gateway.SplitJID(p.From)
+			if !ok {
+				presenceReplySetError(reply, 400)
+				return
+			}
+
+			session, ok := sessions[fromBare]
+			if !ok || !session.Session.MUC {
+				presenceReplySetError(reply, 407)
+				return
+			}
+
+			chat, _, err := session.GetContactByID(chatId, nil)
+			if err != nil || !session.IsGroup(chat) {
+				presenceReplySetError(reply, 404)
+				return
+			}
+
+			limit, ok := mucExt.History.MaxStanzas.Get()
+			if !ok {
+				limit = 20
+			}
+			session.JoinMUC(chatId, fromResource, int32(limit))
+		}
+	}
+}
+
+func tryHandleMUCNicknameChange(s xmpp.Sender, p stanza.Presence) {
+	log.WithFields(log.Fields{
+		"type": p.Type,
+		"from": p.From,
+		"to":   p.To,
+	}).Warn("Nickname change presence?")
+	log.Debugf("%#v", p)
+
+	if p.Type != "" {
+		return
+	}
+
+	toBare, nickname, ok := gateway.SplitJID(p.To)
+	if !ok || nickname == "" {
+		return
+	}
+
+	fromBare, fromResource, ok := gateway.SplitJID(p.From)
+	if !ok {
+		return
+	}
+
+	session, ok := sessions[fromBare]
+	if !ok || !session.Session.MUC {
+		return
+	}
+
+	chatId, ok := toToID(toBare)
+	if !ok {
+		return
+	}
+
+	chat, _, err := session.GetContactByID(chatId, nil)
+	if err != nil || !session.IsGroup(chat) {
+		return
+	}
+
+	if !session.MUCHasResource(chatId, fromResource) {
+		return
+	}
+
+	log.Warn("🗿 Yes")
+
+	component, ok := s.(*xmpp.Component)
+	if !ok {
+		log.Error("Not a component")
+		return
+	}
+
+	from := toBare
+	nickname, ok = session.GetMyMUCNickname(chatId)
+	if ok {
+		from = from+"/"+nickname
+	}
+	reply := &stanza.Presence{
+		Attrs: stanza.Attrs{
+			From:  from,
+			To:    p.From,
+			Id:    p.Id,
+			Type:  stanza.PresenceTypeError,
+		},
+		Error: stanza.Err{
+			Code:   406,
+			Type:   stanza.ErrorTypeModify,
+			Reason: "not-acceptable",
+			Text:   "Telegram does not support changing nicknames per-chat. Issue a /setname command to the transport if you wish to change the global name",
+		},
+	}
+	gateway.ResumableSend(component, reply)
+}
+
 func handleGetVcardIq(s xmpp.Sender, iq *stanza.IQ, typ byte) {
 	log.WithFields(log.Fields{
 		"from": iq.From,
@@ -441,7 +621,7 @@ func handleGetVcardIq(s xmpp.Sender, iq *stanza.IQ, typ byte) {
 	_ = gateway.ResumableSend(component, &answer)
 }
 
-func handleGetDiscoInfo(s xmpp.Sender, iq *stanza.IQ) {
+func handleGetDisco(dt discoType, s xmpp.Sender, iq *stanza.IQ) {
 	answer, err := stanza.NewIQ(stanza.Attrs{
 		Type: stanza.IQTypeResult,
 		From: iq.To,
@@ -454,15 +634,90 @@ func handleGetDiscoInfo(s xmpp.Sender, iq *stanza.IQ) {
 		return
 	}
 
+	if dt == discoTypeInfo {
 		disco := answer.DiscoInfo()
-	_, ok := toToID(iq.To)
+		toID, toOk := toToID(iq.To)
-	if ok {
+		if !toOk {
-		disco.AddIdentity("", "account", "registered")
-	} else {
 			disco.AddIdentity("Telegram Gateway", "gateway", "telegram")
 			disco.AddFeatures("jabber:iq:register")
 		}
+
+		var isMuc bool
+		bare, _, fromOk := gateway.SplitJID(iq.From)
+		if fromOk {
+			session, sessionOk := sessions[bare]
+			if sessionOk && session.Session.MUC {
+				if toOk {
+					chat, _, err := session.GetContactByID(toID, nil)
+					if err == nil && session.IsGroup(chat) {
+						isMuc = true
+						disco.AddIdentity(chat.Title, "conference", "text")
+
+						disco.AddFeatures(
+							"http://jabber.org/protocol/muc",
+							"muc_persistent",
+							"muc_hidden",
+							"muc_membersonly",
+							"muc_unmoderated",
+							"muc_nonanonymous",
+							"muc_unsecured",
+							"http://jabber.org/protocol/muc#stable_id",
+						)
+						fields := []*stanza.Field{
+							&stanza.Field{
+								Var:        "FORM_TYPE",
+								Type:       "hidden",
+								ValuesList: []string{"http://jabber.org/protocol/muc#roominfo"},
+							},
+							&stanza.Field{
+								Var:        "muc#roominfo_description",
+								Label:      "Description",
+								ValuesList: []string{session.GetChatDescription(chat)},
+							},
+							&stanza.Field{
+								Var:        "muc#roominfo_occupants",
+								Label:      "Number of occupants",
+								ValuesList: []string{strconv.FormatInt(int64(session.GetChatMemberCount(chat)), 10)},
+							},
+						}
+
+						disco.Form = stanza.NewForm(fields, "result")
+					}
+				} else {
+					disco.AddFeatures(
+						stanza.NSDiscoItems,
+						"http://jabber.org/protocol/muc#stable_id",
+					)
+					disco.AddIdentity("Telegram group chats", "conference", "text")
+				}
+			}
+		}
+		if toOk && !isMuc {
+			disco.AddIdentity("", "account", "registered")
+		}
 		answer.Payload = disco
+	} else if dt == discoTypeItems {
+		disco := answer.DiscoItems()
+
+		_, ok := toToID(iq.To)
+		if !ok {
+			bare, _, ok := gateway.SplitJID(iq.From)
+			if ok {
+				// raw access, no need to create a new instance if not connected
+				session, ok := sessions[bare]
+				if ok && session.Session.MUC {
+					bareJid := gateway.Jid.Bare()
+					disco.AddItem(bareJid, "", "Telegram group chats")
+					for _, chat := range session.GetGroupChats() {
+						jid := strconv.FormatInt(chat.Id, 10) + "@" + bareJid
+						disco.AddItem(jid, "", chat.Title)
+					}
+				}
+			}
+		}
+
+		answer.Payload = disco
+	}
 
 	log.Debugf("%#v", answer)
 
@@ -475,30 +730,6 @@ func handleGetDiscoInfo(s xmpp.Sender, iq *stanza.IQ) {
 	_ = gateway.ResumableSend(component, answer)
 }
 
-func handleGetDiscoItems(s xmpp.Sender, iq *stanza.IQ) {
-	answer, err := stanza.NewIQ(stanza.Attrs{
-		Type: stanza.IQTypeResult,
-		From: iq.To,
-		To:   iq.From,
-		Id:   iq.Id,
-		Lang: "en",
-	})
-	if err != nil {
-		log.Errorf("Failed to create answer IQ: %v", err)
-		return
-	}
-
-	answer.Payload = answer.DiscoItems()
-
-	component, ok := s.(*xmpp.Component)
-	if !ok {
-		log.Error("Not a component")
-		return
-	}
-
-	_ = gateway.ResumableSend(component, answer)
-}
-
 func handleGetQueryRegister(s xmpp.Sender, iq *stanza.IQ) {
 	component, ok := s.(*xmpp.Component)
 	if !ok {
@@ -658,6 +889,28 @@ func iqAnswerSetError(answer *stanza.IQ, payload *extensions.QueryRegister, code
 	}
 }
 
+func presenceReplySetError(reply *stanza.Presence, code int) {
+	reply.Type = stanza.PresenceTypeError
+	reply.Error = stanza.Err{
+		Code: code,
+	}
+	switch code {
+	case 400:
+		reply.Error.Type = stanza.ErrorTypeModify
+		reply.Error.Reason = "jid-malformed"
+	case 407:
+		reply.Error.Type = stanza.ErrorTypeAuth
+		reply.Error.Reason = "registration-required"
+	case 404:
+		reply.Error.Type = stanza.ErrorTypeCancel
+		reply.Error.Reason = "item-not-found"
+	default:
+		log.Error("Unknown error code, falling back with empty reason")
+		reply.Error.Type = stanza.ErrorTypeCancel
+		reply.Error.Reason = "undefined-condition"
+	}
+}
+
 func toToID(to string) (int64, bool) {
 	toParts := strings.Split(to, "@")
 	if len(toParts) < 2 {