Send the display name instead of the user name (matrix) (#1282)

* matrix: send the display name (the nickname in matrix parlance) instead of the user name

There is also the option UseUserName (already in use by the discord bridge) to turn back to the old behavior.

* matrix: update displayNames on join events

* matrix: introduce a helper.go file to keep matrix.go size reasonable

1 files changed, 37 insertions, 110 deletions

diff --git a/bridge/matrix/matrix.go b/bridge/matrix/matrix.go
index fa2a3f80..725f49a6 100644
--- a/bridge/matrix/matrix.go
+++ b/bridge/matrix/matrix.go
@@ -2,9 +2,7 @@ package bmatrix
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
-	"html"
 	"mime"
 	"regexp"
 	"strings"
@@ -22,10 +20,16 @@ var (
 	htmlReplacementTag = regexp.MustCompile("<[^>]*>")
 )
 
+type NicknameCacheEntry struct {
+	displayName string
+	lastUpdated time.Time
+}
+
 type Bmatrix struct {
-	mc      *matrix.Client
-	UserID  string
-	RoomMap map[string]string
+	mc          *matrix.Client
+	UserID      string
+	NicknameMap map[string]NicknameCacheEntry
+	RoomMap     map[string]string
 	sync.RWMutex
 	*bridge.Config
 }
@@ -41,25 +45,29 @@ type matrixUsername struct {
 	formatted string
 }
 
-func newMatrixUsername(username string) *matrixUsername {
-	mUsername := new(matrixUsername)
-
-	// check if we have a </tag>. if we have, we don't escape HTML. #696
-	if htmlTag.MatchString(username) {
-		mUsername.formatted = username
-		// remove the HTML formatting for beautiful push messages #1188
-		mUsername.plain = htmlReplacementTag.ReplaceAllString(username, "")
-	} else {
-		mUsername.formatted = html.EscapeString(username)
-		mUsername.plain = username
-	}
+// SubTextMessage represents the new content of the message in edit messages.
+type SubTextMessage struct {
+	MsgType string `json:"msgtype"`
+	Body    string `json:"body"`
+}
+
+// MessageRelation explains how the current message relates to a previous message.
+// Notably used for message edits.
+type MessageRelation struct {
+	EventID string `json:"event_id"`
+	Type    string `json:"rel_type"`
+}
 
-	return mUsername
+type EditedMessage struct {
+	NewContent SubTextMessage  `json:"m.new_content"`
+	RelatedTo  MessageRelation `json:"m.relates_to"`
+	matrix.TextMessage
 }
 
 func New(cfg *bridge.Config) bridge.Bridger {
 	b := &Bmatrix{Config: cfg}
 	b.RoomMap = make(map[string]string)
+	b.NicknameMap = make(map[string]NicknameCacheEntry)
 	return b
 }
 
@@ -112,22 +120,6 @@ retry:
 	return nil
 }
 
-type SubTextMessage struct {
-	MsgType string `json:"msgtype"`
-	Body    string `json:"body"`
-}
-
-type MessageRelation struct {
-	EventID string `json:"event_id"`
-	Type    string `json:"rel_type"`
-}
-
-type EditedMessage struct {
-	NewContent SubTextMessage  `json:"m.new_content"`
-	RelatedTo  MessageRelation `json:"m.relates_to"`
-	matrix.TextMessage
-}
-
 func (b *Bmatrix) Send(msg config.Message) (string, error) {
 	b.Log.Debugf("=> Receiving %#v", msg)
 
@@ -233,21 +225,11 @@ func (b *Bmatrix) Send(msg config.Message) (string, error) {
 	return resp.EventID, err
 }
 
-func (b *Bmatrix) getRoomID(channel string) string {
-	b.RLock()
-	defer b.RUnlock()
-	for ID, name := range b.RoomMap {
-		if name == channel {
-			return ID
-		}
-	}
-	return ""
-}
-
 func (b *Bmatrix) handlematrix() {
 	syncer := b.mc.Syncer.(*matrix.DefaultSyncer)
 	syncer.OnEventType("m.room.redaction", b.handleEvent)
 	syncer.OnEventType("m.room.message", b.handleEvent)
+	syncer.OnEventType("m.room.member", b.handleMemberChange)
 	go func() {
 		for {
 			if err := b.mc.Sync(); err != nil {
@@ -257,15 +239,6 @@ func (b *Bmatrix) handlematrix() {
 	}()
 }
 
-func interface2Struct(in interface{}, out interface{}) error {
-	jsonObj, err := json.Marshal(in)
-	if err != nil {
-		return err
-	}
-
-	return json.Unmarshal(jsonObj, out)
-}
-
 func (b *Bmatrix) handleEdit(ev *matrix.Event, rmsg config.Message) bool {
 	relationInterface, present := ev.Content["m.relates_to"]
 	newContentInterface, present2 := ev.Content["m.new_content"]
@@ -296,6 +269,15 @@ func (b *Bmatrix) handleEdit(ev *matrix.Event, rmsg config.Message) bool {
 	return true
 }
 
+func (b *Bmatrix) handleMemberChange(ev *matrix.Event) {
+	// Update the displayname on join messages, according to https://matrix.org/docs/spec/client_server/r0.6.1#events-on-change-of-profile-information
+	if ev.Content["membership"] == "join" {
+		if dn, ok := ev.Content["displayname"].(string); ok {
+			b.cacheDisplayName(ev.Sender, dn)
+		}
+	}
+}
+
 func (b *Bmatrix) handleEvent(ev *matrix.Event) {
 	b.Log.Debugf("== Receiving event: %#v", ev)
 	if ev.Sender != b.UserID {
@@ -309,7 +291,7 @@ func (b *Bmatrix) handleEvent(ev *matrix.Event) {
 
 		// Create our message
 		rmsg := config.Message{
-			Username: ev.Sender[1:],
+			Username: b.getDisplayName(ev.Sender),
 			Channel:  channel,
 			Account:  b.Account,
 			UserID:   ev.Sender,
@@ -494,58 +476,3 @@ func (b *Bmatrix) handleUploadFile(msg *config.Message, channel string, fi *conf
 	}
 	b.Log.Debugf("result: %#v", res)
 }
-
-// skipMessages returns true if this message should not be handled
-func (b *Bmatrix) containsAttachment(content map[string]interface{}) bool {
-	// Skip empty messages
-	if content["msgtype"] == nil {
-		return false
-	}
-
-	// Only allow image,video or file msgtypes
-	if !(content["msgtype"].(string) == "m.image" ||
-		content["msgtype"].(string) == "m.video" ||
-		content["msgtype"].(string) == "m.file") {
-		return false
-	}
-	return true
-}
-
-// getAvatarURL returns the avatar URL of the specified sender
-func (b *Bmatrix) getAvatarURL(sender string) string {
-	urlPath := b.mc.BuildURL("profile", sender, "avatar_url")
-
-	s := struct {
-		AvatarURL string `json:"avatar_url"`
-	}{}
-
-	err := b.mc.MakeRequest("GET", urlPath, nil, &s)
-	if err != nil {
-		b.Log.Errorf("getAvatarURL failed: %s", err)
-		return ""
-	}
-	url := strings.ReplaceAll(s.AvatarURL, "mxc://", b.GetString("Server")+"/_matrix/media/r0/thumbnail/")
-	if url != "" {
-		url += "?width=37&height=37&method=crop"
-	}
-	return url
-}
-
-func handleError(err error) *httpError {
-	mErr, ok := err.(matrix.HTTPError)
-	if !ok {
-		return &httpError{
-			Err: "not a HTTPError",
-		}
-	}
-
-	var httpErr httpError
-
-	if err := json.Unmarshal(mErr.Contents, &httpErr); err != nil {
-		return &httpError{
-			Err: "unmarshal failed",
-		}
-	}
-
-	return &httpErr
-}