From 81b3af8b8771cf45679a7c985f70f819ddb5067a Mon Sep 17 00:00:00 2001
From: Andrey Chugunov <andrey@chugunov.me>
Date: Wed, 20 Apr 2022 04:05:29 +0400
Subject: [PATCH] Improve Slack attachments formatting (slack)

* Add TitleLink
* Add Footer
---
 bridge/slack/handlers.go | 13 ++++++++++++-
 bridge/slack/helpers.go  | 11 ++---------
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/bridge/slack/handlers.go b/bridge/slack/handlers.go
index c469b9a5..8320e4f8 100644
--- a/bridge/slack/handlers.go
+++ b/bridge/slack/handlers.go
@@ -282,6 +282,14 @@ func (b *Bslack) handleStatusEvent(ev *slack.MessageEvent, rmsg *config.Message)
 	return false
 }
 
+func getMessageTitle(attach *slack.Attachment) string {
+	if attach.TitleLink != "" {
+		return fmt.Sprintf("[%s](%s)\n", attach.Title, attach.TitleLink)
+	} else {
+		return attach.Title
+	}
+}
+
 func (b *Bslack) handleAttachments(ev *slack.MessageEvent, rmsg *config.Message) {
 	// File comments are set by the system (because there is no username given).
 	if ev.SubType == sFileComment {
@@ -293,9 +301,12 @@ func (b *Bslack) handleAttachments(ev *slack.MessageEvent, rmsg *config.Message)
 		for _, attach := range ev.Attachments {
 			if attach.Text != "" {
 				if attach.Title != "" {
-					rmsg.Text = attach.Title + "\n"
+					rmsg.Text = getMessageTitle(&attach)
 				}
 				rmsg.Text += attach.Text
+				if attach.Footer != "" {
+					rmsg.Text += "\n\n" + attach.Footer
+				}
 			} else {
 				rmsg.Text = attach.Fallback
 			}
diff --git a/bridge/slack/helpers.go b/bridge/slack/helpers.go
index bdacd7ee..e46e2725 100644
--- a/bridge/slack/helpers.go
+++ b/bridge/slack/helpers.go
@@ -127,7 +127,7 @@ var (
 	mentionRE        = regexp.MustCompile(`<@([a-zA-Z0-9]+)>`)
 	channelRE        = regexp.MustCompile(`<#[a-zA-Z0-9]+\|(.+?)>`)
 	variableRE       = regexp.MustCompile(`<!((?:subteam\^)?[a-zA-Z0-9]+)(?:\|@?(.+?))?>`)
-	urlRE            = regexp.MustCompile(`<(.*?)(\|.*?)?>`)
+	urlRE            = regexp.MustCompile(`<([^<\|]+)\|([^>]+)>`)
 	codeFenceRE      = regexp.MustCompile(`(?m)^` + "```" + `\w+$`)
 	topicOrPurposeRE = regexp.MustCompile(`(?s)(@.+) (cleared|set)(?: the)? channel (topic|purpose)(?:: (.*))?`)
 )
@@ -181,14 +181,7 @@ func (b *Bslack) replaceVariable(text string) string {
 
 // @see https://api.slack.com/docs/message-formatting#linking_to_urls
 func (b *Bslack) replaceURL(text string) string {
-	for _, r := range urlRE.FindAllStringSubmatch(text, -1) {
-		if len(strings.TrimSpace(r[2])) == 1 { // A display text separator was found, but the text was blank
-			text = strings.Replace(text, r[0], "", 1)
-		} else {
-			text = strings.Replace(text, r[0], r[1], 1)
-		}
-	}
-	return text
+	return urlRE.ReplaceAllString(text, "[${2}](${1})")
 }
 
 func (b *Bslack) replaceb0rkedMarkDown(text string) string {