1 files changed, 344 insertions, 0 deletions
diff --git a/bridge/matrix/handlers.go b/bridge/matrix/handlers.go
new file mode 100644
index 00000000..8833b0ed
--- /dev/null
+++ b/bridge/matrix/handlers.go
@@ -0,0 +1,344 @@
+package bmatrix
+
+import (
+	"bytes"
+	"fmt"
+	"mime"
+	"regexp"
+	"strings"
+
+	matrix "maunium.net/go/mautrix"
+	"maunium.net/go/mautrix/event"
+	"maunium.net/go/mautrix/id"
+
+	"github.com/42wim/matterbridge/bridge/config"
+	"github.com/42wim/matterbridge/bridge/helper"
+)
+
+// Determines if the event comes from ourselves, in which case we want to ignore it
+func (b *Bmatrix) ignoreBridgingEvents(ev *event.Event) bool {
+	if ev.Sender == b.UserID {
+		return true
+	}
+
+	// ignore messages we may have sent via the appservice
+	if b.appService != nil {
+		if ev.Sender == b.appService.appService.BotClient().UserID {
+			return true
+		}
+
+		// ignore virtual users messages (we ignore the 'exclusive' field of Namespace for now)
+		for _, username := range b.appService.namespaces.usernames {
+			if username.MatchString(ev.Sender.String()) {
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+//nolint: funlen
+func (b *Bmatrix) handleEvent(origin EventOrigin, ev *event.Event) {
+	if b.ignoreBridgingEvents(ev) {
+		return
+	}
+
+	b.RLock()
+	channel, ok := b.RoomMap[ev.RoomID]
+	b.RUnlock()
+	if !ok {
+		// we don't know that room yet, that could be a room returned by an
+		// application service, but matterbridge doesn't handle those just yet
+		b.Log.Debugf("Received event for room %s, not joined yet/not handled", ev.RoomID)
+
+		return
+	}
+
+	if ev.Type == event.EphemeralEventReceipt {
+		// we do not support read receipts across servers, considering that
+		// multiple services (e.g. Discord) doesn't expose that information)
+		return
+	}
+
+	if ev.Type == event.StateMember {
+		b.handleMemberChange(ev)
+
+		return
+	}
+
+	// if we receive appservice events for this room, there is no need to check them with the classical syncer
+	if !channel.appService && origin == originAppService {
+		channel.appService = true
+		b.Lock()
+		b.RoomMap[ev.RoomID] = channel
+		b.Unlock()
+	}
+
+	// if we receive messages both via the classical matrix syncer and appserver, prefer appservice and throw away this duplicate event
+	if channel.appService && origin != originAppService {
+		b.Log.Debugf("Dropping event, should receive it via appservice: %s", ev.ID)
+
+		return
+	}
+
+	b.Log.Debugf("== Receiving event: %#v (appService=%t)", ev, origin == originAppService)
+
+	if ev.Type == event.EphemeralEventTyping {
+		typing := ev.Content.AsTyping()
+		if len(typing.UserIDs) > 0 {
+			//nolint:exhaustruct
+			b.Remote <- config.Message{
+				Event:   config.EventUserTyping,
+				Channel: channel.name,
+				Account: b.Account,
+			}
+		}
+
+		return
+	}
+
+	defer (func(ev *event.Event) {
+		// not crucial, so no ratelimit check here
+		if err := b.mc.MarkRead(ev.RoomID, ev.ID); err != nil {
+			b.Log.Errorf("couldn't mark message as read %s", err.Error())
+		}
+	})(ev)
+
+	// Create our message
+	//nolint:exhaustruct
+	rmsg := config.Message{
+		Username: b.getDisplayName(ev.RoomID, ev.Sender),
+		Channel:  channel.name,
+		Account:  b.Account,
+		UserID:   string(ev.Sender),
+		ID:       string(ev.ID),
+	}
+
+	// Remove homeserver suffix if configured
+	if b.GetBool("NoHomeServerSuffix") {
+		re := regexp.MustCompile("(.*?):.*")
+		rmsg.Username = re.ReplaceAllString(rmsg.Username, `$1`)
+	}
+
+	// Delete event
+	if ev.Type == event.EventRedaction {
+		rmsg.Event = config.EventMsgDelete
+		rmsg.ID = string(ev.Redacts)
+		rmsg.Text = config.EventMsgDelete
+		b.Remote <- rmsg
+
+		return
+	}
+
+	b.handleMessage(rmsg, ev)
+}
+
+func (b *Bmatrix) handleMemberChange(ev *event.Event) {
+	member := ev.Content.AsMember()
+	if member == nil {
+		b.Log.Errorf("Couldn't process a member event:\n%#v", ev)
+
+		return
+	}
+
+	// Update the displayname on join messages, according to https://spec.matrix.org/v1.3/client-server-api/#events-on-change-of-profile-information
+	if member.Membership == event.MembershipJoin {
+		b.cacheDisplayName(ev.RoomID, ev.Sender, member.Displayname)
+	} else if member.Membership == event.MembershipLeave || member.Membership == event.MembershipBan {
+		b.removeDisplayNameFromCache(ev.Sender)
+	}
+}
+
+func (b *Bmatrix) handleMessage(rmsg config.Message, ev *event.Event) {
+	msg := ev.Content.AsMessage()
+	if msg == nil {
+		b.Log.Errorf("matterbridge don't support this event type: %s", ev.Type.Type)
+		b.Log.Debugf("Full event: %#v", ev)
+
+		return
+	}
+
+	rmsg.Text = msg.Body
+
+	// TODO: cache the avatars
+	avatarURL := b.getAvatarURL(ev.Sender)
+	contentURI, err := id.ParseContentURI(avatarURL)
+	if err == nil {
+		avatarURL = b.mc.GetDownloadURL(contentURI)
+		rmsg.Avatar = avatarURL
+	}
+
+	// Do we have a /me action
+	//nolint: exhaustive
+	switch msg.MsgType {
+	case event.MsgEmote:
+		rmsg.Event = config.EventUserAction
+	case event.MsgImage, event.MsgVideo, event.MsgFile:
+		// Do we have attachments? (we only allow images, videos or files msgtypes)
+		err := b.handleDownloadFile(&rmsg, *msg)
+		if err != nil {
+			b.Log.Errorf("download failed: %#v", err)
+		}
+	default:
+		if msg.RelatesTo == nil {
+			break
+		}
+
+		if msg.RelatesTo.Type == event.RelReplace && msg.NewContent != nil {
+			// Is it an edit?
+			rmsg.ID = string(msg.RelatesTo.EventID)
+			rmsg.Text = msg.NewContent.Body
+		} else if msg.RelatesTo.Type == event.RelReference && msg.RelatesTo.InReplyTo != nil {
+			// Is it a reply?
+			body := msg.Body
+			if !b.GetBool("keepquotedreply") {
+				for strings.HasPrefix(body, "> ") {
+					lineIdx := strings.Index(body, "\n\n")
+					if lineIdx == -1 {
+						break
+					}
+
+					body = body[(lineIdx + 2):]
+				}
+			}
+
+			rmsg.ParentID = string(msg.RelatesTo.EventID)
+			rmsg.Text = body
+		}
+	}
+
+	b.Log.Debugf("<= Sending message from %s on %s to gateway", ev.Sender, b.Account)
+	b.Remote <- rmsg
+}
+
+// handleDownloadFile handles file download
+func (b *Bmatrix) handleDownloadFile(rmsg *config.Message, msg event.MessageEventContent) error {
+	rmsg.Extra = make(map[string][]interface{})
+	if msg.URL == "" || msg.Info == nil {
+		b.Log.Error("couldn't download a file with no URL or no file informations (invalid event ?)")
+		b.Log.Debugf("Full Message content:\n%#v", msg)
+	}
+
+	url := strings.ReplaceAll(string(msg.URL), "mxc://", b.GetString("Server")+"/_matrix/media/v1/download/")
+	filename := msg.Body
+
+	// check if we have an image uploaded without extension
+	if !strings.Contains(filename, ".") {
+		mext, _ := mime.ExtensionsByType(msg.Info.MimeType)
+		if len(mext) > 0 {
+			filename += mext[0]
+		} else if msg.MsgType == event.MsgImage {
+			// just a default .png extension if we don't have mime info
+			filename += ".png"
+		}
+	}
+
+	// check if the size is ok
+	err := helper.HandleDownloadSize(b.Log, rmsg, filename, int64(msg.Info.Size), b.General)
+	if err != nil {
+		return err
+	}
+	// actually download the file
+	data, err := helper.DownloadFile(url)
+	if err != nil {
+		return fmt.Errorf("download %s failed %#v", url, err)
+	}
+	// add the downloaded data to the message
+	helper.HandleDownloadData(b.Log, rmsg, filename, "", url, data, b.General)
+	return nil
+}
+
+// handleUploadFiles handles native upload of files.
+func (b *Bmatrix) handleUploadFiles(msg *config.Message, channel id.RoomID) (string, error) {
+	for _, f := range msg.Extra["file"] {
+		if fi, ok := f.(config.FileInfo); ok {
+			b.handleUploadFile(msg, channel, &fi)
+		}
+	}
+	return "", nil
+}
+
+// handleUploadFile handles native upload of a file.
+//nolint: funlen
+func (b *Bmatrix) handleUploadFile(msg *config.Message, channel id.RoomID, fi *config.FileInfo) {
+	content := bytes.NewReader(*fi.Data)
+	sp := strings.Split(fi.Name, ".")
+	mtype := mime.TypeByExtension("." + sp[len(sp)-1])
+
+	// image and video uploads send no username, we have to do this ourself here #715
+	//nolint:exhaustruct
+	m := event.MessageEventContent{
+		MsgType:       event.MsgText,
+		Body:          fi.Comment,
+		FormattedBody: fi.Comment,
+	}
+
+	_, err := b.sendMessageEventWithRetries(channel, m, msg.Username)
+	if err != nil {
+		b.Log.Errorf("file comment failed: %#v", err)
+	}
+
+	b.Log.Debugf("uploading file: %s %s", fi.Name, mtype)
+
+	var res *matrix.RespMediaUpload
+	//nolint:exhaustruct
+	req := matrix.ReqUploadMedia{
+		Content:       content,
+		ContentType:   mtype,
+		ContentLength: fi.Size,
+	}
+
+	err = b.retry(func() error {
+		res, err = b.mc.UploadMedia(req)
+
+		return err
+	})
+
+	if err != nil {
+		b.Log.Errorf("file upload failed: %#v", err)
+		return
+	}
+
+	b.Log.Debugf("result: %#v", res)
+
+	//nolint:exhaustruct
+	m = event.MessageEventContent{
+		Body: fi.Name,
+		URL:  res.ContentURI.CUString(),
+	}
+
+	switch {
+	case strings.Contains(mtype, "video"):
+		b.Log.Debugf("sendVideo %s", res.ContentURI)
+
+		m.MsgType = event.MsgVideo
+	case strings.Contains(mtype, "image"):
+		b.Log.Debugf("sendImage %s", res.ContentURI)
+
+		m.MsgType = event.MsgImage
+	case strings.Contains(mtype, "audio"):
+		b.Log.Debugf("sendAudio %s", res.ContentURI)
+
+		m.MsgType = event.MsgAudio
+		//nolint:exhaustruct
+		m.Info = &event.FileInfo{
+			MimeType: mtype,
+			Size:     len(*fi.Data),
+		}
+	default:
+		b.Log.Debugf("sendFile %s", res.ContentURI)
+
+		m.MsgType = event.MsgFile
+		//nolint:exhaustruct
+		m.Info = &event.FileInfo{
+			MimeType: mtype,
+			Size:     len(*fi.Data),
+		}
+	}
+
+	_, err = b.sendMessageEventWithRetries(channel, m, msg.Username)
+	if err != nil {
+		b.Log.Errorf("sending the message referencing the uploaded file failed: %#v", err)
+	}
+}