matrix+irc: improve support for IRC NOTICE/[matrix] m.notice

Fixes: #1393.

bridge/config/config.go

@@ -27,7 +27,7 @@ const (
 	EventAPIConnected      = "api_connected"
 	EventUserTyping        = "user_typing"
 	EventGetChannelMembers = "get_channel_members"
-	EventNoticeIRC         = "notice_irc"
+	EventNotice            = "notice"
 )
 
 const ParentIDNotFound = "msg-parent-not-found"

bridge/irc/handlers.go

@@ -201,7 +201,7 @@ func (b *Birc) handlePrivMsg(client *girc.Client, event girc.Event) {
 
 	// set NOTICE event
 	if event.Command == "NOTICE" {
-		rmsg.Event = config.EventNoticeIRC
+		rmsg.Event = config.EventNotice
 	}
 
 	// strip action, we made an event if it was an action

bridge/irc/irc.go

@@ -255,7 +255,7 @@ func (b *Birc) doSend() {
 			switch msg.Event {
 			case config.EventUserAction:
 				b.i.Cmd.Action(msg.Channel, username+msg.Text)
-			case config.EventNoticeIRC:
+			case config.EventNotice:
 				b.Log.Debugf("Sending notice to channel %s", msg.Channel)
 				b.i.Cmd.Notice(msg.Channel, username+msg.Text)
 			default:

bridge/matrix/handlers.go

@@ -150,6 +150,7 @@ func (b *Bmatrix) handleMemberChange(ev *event.Event) {
 	}
 }
 
+//nolint: funlen
 func (b *Bmatrix) handleMessage(rmsg config.Message, ev *event.Event) {
 	msg := ev.Content.AsMessage()
 	if msg == nil {
@@ -169,10 +170,10 @@ func (b *Bmatrix) handleMessage(rmsg config.Message, ev *event.Event) {
 		rmsg.Avatar = avatarURL
 	}
 
-	// Do we have a /me action
 	//nolint: exhaustive
 	switch msg.MsgType {
 	case event.MsgEmote:
+		// Do we have a /me action
 		rmsg.Event = config.EventUserAction
 	case event.MsgImage, event.MsgVideo, event.MsgFile:
 		// Do we have attachments? (we only allow images, videos or files msgtypes)
@@ -180,6 +181,9 @@ func (b *Bmatrix) handleMessage(rmsg config.Message, ev *event.Event) {
 		if err != nil {
 			b.Log.Errorf("download failed: %#v", err)
 		}
+	case event.MsgNotice:
+		// Support for IRC NOTICE commands/[matrix] m.notice
+		rmsg.Event = config.EventNotice
 	default:
 		if msg.RelatesTo == nil {
 			break

bridge/matrix/matrix.go

@@ -195,6 +195,7 @@ func (b *Bmatrix) Start() error {
 	return nil
 }
 
+//nolint: funlen,gocognit,gocyclo
 func (b *Bmatrix) Send(msg config.Message) (string, error) {
 	b.Log.Debugf("=> Sending %#v", msg)
 
@@ -305,7 +306,7 @@ func (b *Bmatrix) Send(msg config.Message) (string, error) {
 	}
 
 	// Use notices to send join/leave events
-	if msg.Event == config.EventJoinLeave {
+	if msg.Event == config.EventJoinLeave || msg.Event == config.EventNotice {
 		m.MsgType = event.MsgNotice
 	} else {
 		m.MsgType = event.MsgText

gateway/bridgemap/birc.go

@@ -1,3 +1,4 @@
+//go:build !noirc
 // +build !noirc
 
 package bridgemap
@@ -8,4 +9,5 @@ import (
 
 func init() {
 	FullMap["irc"] = birc.New
+	NoticeSupport["irc"] = struct{}{}
 }

gateway/bridgemap/bmatrix.go

@@ -1,3 +1,4 @@
+//go:build !nomatrix
 // +build !nomatrix
 
 package bridgemap
@@ -9,4 +10,5 @@ import (
 func init() {
 	FullMap["matrix"] = bmatrix.New
 	UserTypingSupport["matrix"] = struct{}{}
+	NoticeSupport["matrix"] = struct{}{}
 }

gateway/bridgemap/bridgemap.go

@@ -7,4 +7,5 @@ import (
 var (
 	FullMap           = map[string]bridge.Factory{}
 	UserTypingSupport = map[string]struct{}{}
+	NoticeSupport     = map[string]struct{}{}
 )

gateway/gateway.go

@@ -450,11 +450,6 @@ func (gw *Gateway) SendMessage(
 		}
 	}
 
-	// Only send irc notices to irc
-	if msg.Event == config.EventNoticeIRC && dest.Protocol != "irc" {
-		return "", nil
-	}
-
 	// Too noisy to log like other events
 	debugSendMessage := ""
 	if msg.Event != config.EventUserTyping {

gateway/handlers.go

@@ -199,6 +199,17 @@ func (gw *Gateway) handleMessage(rmsg *config.Message, dest *bridge.Bridge) []*B
 		}
 	}
 
+	if rmsg.Event == config.EventNotice {
+		if _, ok := bridgemap.NoticeSupport[dest.Protocol]; !ok {
+			// we are forced to clone the pointer, as `rmsg` is re-used across calls to handleMessage
+			newMsg := *rmsg
+			// if the destination doesn't support IRC/Matrix 'notices',
+			// emit a normal message
+			newMsg.Event = ""
+			rmsg = &newMsg
+		}
+	}
+
 	// if we have an attached file, or other info
 	if rmsg.Extra != nil && len(rmsg.Extra[config.EventFileFailureSize]) != 0 && rmsg.Text == "" {
 		return brMsgIDs