From 198625eb9b3bb0e967cdda652029dba3185e9059 Mon Sep 17 00:00:00 2001
From: Tulir Asokan <tulir@maunium.net>
Date: Mon, 5 Aug 2024 14:14:53 +0300
Subject: [PATCH] just copy old incoming mention parsing

---
 messagix/socket/threads.go        |   2 +-
 pkg/connector/msgconv/mentions.go | 117 +++++++++++-------------------
 2 files changed, 44 insertions(+), 75 deletions(-)

diff --git a/messagix/socket/threads.go b/messagix/socket/threads.go
index abd444c..da986db 100644
--- a/messagix/socket/threads.go
+++ b/messagix/socket/threads.go
@@ -53,7 +53,7 @@ type MentionData struct {
 }
 
 func (md *MentionData) Parse() (Mentions, error) {
-	if len(md.MentionIDs) == 0 {
+	if md == nil || len(md.MentionIDs) == 0 {
 		return nil, nil
 	}
 	mentionIDs := strings.Split(md.MentionIDs, ",")
diff --git a/pkg/connector/msgconv/mentions.go b/pkg/connector/msgconv/mentions.go
index 8ae15f3..5d74c66 100644
--- a/pkg/connector/msgconv/mentions.go
+++ b/pkg/connector/msgconv/mentions.go
@@ -18,9 +18,6 @@ package msgconv
 
 import (
 	"context"
-	"regexp"
-	"slices"
-
 	//"log"
 	"strings"
 	"unicode/utf16"
@@ -43,88 +40,60 @@ func (u UTF16String) String() string {
 	return string(utf16.Decode(u))
 }
 
-var (
-	META_BOLD_REGEX            = regexp.MustCompile(`\*([^*]+)\*`)
-	META_ITALIC_REGEX          = regexp.MustCompile(`_([^_]+)_`)
-	META_STRIKE_REGEX          = regexp.MustCompile(`~([^~]+)~`)
-	META_MONOSPACE_REGEX       = regexp.MustCompile("`([^`]+)`")
-	META_MONOSPACE_BLOCK_REGEX = regexp.MustCompile("```([^`]+)```")
-)
-
 func (mc *MessageConverter) MetaToMatrixText(ctx context.Context, text string, rawMentions *socket.MentionData, portal *bridgev2.Portal) (content *event.MessageEventContent) {
 	content = &event.MessageEventContent{
 		MsgType:  event.MsgText,
 		Body:     text,
 		Mentions: &event.Mentions{},
 	}
-
-	var mentions *socket.Mentions
-
-	if rawMentions != nil {
-		mentionsP, err := rawMentions.Parse()
-		if err != nil {
-			zerolog.Ctx(ctx).Err(err).Msg("Failed to parse mentions")
-		}
-		mentions = &mentionsP
+	mentions, err := rawMentions.Parse()
+	if err != nil {
+		zerolog.Ctx(ctx).Err(err).Msg("Failed to parse mentions")
 	}
-
-	outputString := text
-
-	if mentions != nil {
-		utf16Text := NewUTF16String(text)
-		prevEnd := 0
-		var output strings.Builder
-		for _, mention := range *mentions {
-			if mention.Offset < prevEnd {
-				zerolog.Ctx(ctx).Warn().Msg("Ignoring overlapping mentions in message")
-				continue
-			} else if mention.Offset >= len(utf16Text) {
-				zerolog.Ctx(ctx).Warn().Msg("Ignoring mention outside of message")
-				continue
-			}
-			end := mention.Offset + mention.Length
-			if end > len(utf16Text) {
-				end = len(utf16Text)
-			}
-			var mentionLink string
-			switch mention.Type {
-			case socket.MentionTypePerson:
-				info, err := mc.getBasicUserInfo(ctx, portal, ids.MakeUserID(mention.ID))
-				if err != nil {
-					zerolog.Ctx(ctx).Err(err).Msg("Failed to get user info for mention")
-					continue
-				}
-				if !slices.Contains(content.Mentions.UserIDs, info.MXID) {
-					content.Mentions.UserIDs = append(content.Mentions.UserIDs, info.MXID)
-				}
-				mentionLink = info.MXID.URI().MatrixToURL()
-			case socket.MentionTypeThread:
-				// TODO: how does one send thread mentions?
-			}
-			if mentionLink == "" {
+	if mentions == nil {
+		return
+	}
+	utf16Text := NewUTF16String(text)
+	prevEnd := 0
+	var output strings.Builder
+	for _, mention := range mentions {
+		if mention.Offset < prevEnd {
+			zerolog.Ctx(ctx).Warn().Msg("Ignoring overlapping mentions in message")
+			continue
+		} else if mention.Offset >= len(utf16Text) {
+			zerolog.Ctx(ctx).Warn().Msg("Ignoring mention outside of message")
+			continue
+		}
+		end := mention.Offset + mention.Length
+		if end > len(utf16Text) {
+			end = len(utf16Text)
+		}
+		var mentionLink string
+		switch mention.Type {
+		case socket.MentionTypePerson:
+			info, err := mc.getBasicUserInfo(ctx, portal, ids.MakeUserID(mention.ID))
+			if err != nil {
+				zerolog.Ctx(ctx).Err(err).Msg("Failed to get user info for mention")
 				continue
 			}
-
-			output.WriteString(utf16Text[prevEnd:mention.Offset].String() + `<a href="` + mentionLink + `">` + utf16Text[mention.Offset:end].String() + `</a>`)
-			prevEnd = end
+			content.Mentions.Add(info.MXID)
+			mentionLink = info.MXID.URI().MatrixToURL()
+		case socket.MentionTypeThread:
+			// TODO: how does one send thread mentions?
 		}
-		output.WriteString(utf16Text[prevEnd:].String())
-
-		outputString = output.String()
+		if mentionLink == "" {
+			continue
+		}
+		output.WriteString(utf16Text[prevEnd:mention.Offset].String())
+		output.WriteString(`<a href="`)
+		output.WriteString(mentionLink)
+		output.WriteString(`">`)
+		output.WriteString(utf16Text[mention.Offset:end].String())
+		output.WriteString(`</a>`)
+		prevEnd = end
 	}
-
-	// Second parsing pass, replacing other formatting:
-	outputString = META_BOLD_REGEX.ReplaceAllString(outputString, "<strong>$1</strong>")
-	outputString = META_ITALIC_REGEX.ReplaceAllString(outputString, "<em>$1</em>")
-	outputString = META_STRIKE_REGEX.ReplaceAllString(outputString, "<del>$1</del>")
-	outputString = META_MONOSPACE_REGEX.ReplaceAllString(outputString, "<code>$1</code>")
-	outputString = META_MONOSPACE_BLOCK_REGEX.ReplaceAllString(outputString, "<pre>$1</pre>")
-
+	output.WriteString(utf16Text[prevEnd:].String())
 	content.Format = event.FormatHTML
-	content.FormattedBody = outputString
-
-	log := zerolog.Ctx(ctx)
-	log.Debug().Str("text", text).Str("formatted_body", content.FormattedBody).Msg("Converted message to Matrix text")
-
+	content.FormattedBody = output.String()
 	return content
 }