From 98bc98627d0c81a32a2046a0f4ffe6f7fa8632f5 Mon Sep 17 00:00:00 2001
From: Tulir Asokan <tulir@maunium.net>
Date: Mon, 27 Jun 2022 16:13:26 +0300
Subject: [PATCH] Re-add support for deleting attachments

---
 database/message.go |  8 +++-----
 portal.go           | 22 +++++++++++++++++++++-
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/database/message.go b/database/message.go
index 1dd692e..bf2ca4e 100644
--- a/database/message.go
+++ b/database/message.go
@@ -169,12 +169,10 @@ func (m *Message) Insert() {
 }
 
 func (m *Message) Delete() {
-	query := "DELETE FROM message WHERE dcid=$1 AND dc_chan_id=$2 AND dc_chan_receiver=$3"
-
-	_, err := m.db.Exec(query, m.DiscordID, m.Channel.ChannelID, m.Channel.Receiver)
-
+	query := "DELETE FROM message WHERE dcid=$1 AND dc_chan_id=$2 AND dc_chan_receiver=$3 AND dc_attachment_id=$4"
+	_, err := m.db.Exec(query, m.DiscordID, m.Channel.ChannelID, m.Channel.Receiver, m.AttachmentID)
 	if err != nil {
-		m.log.Warnfln("Failed to delete %s@%s: %v", m.DiscordID, m.Channel, err)
+		m.log.Warnfln("Failed to delete %q of %s@%s: %v", m.AttachmentID, m.DiscordID, m.Channel, err)
 		panic(err)
 	}
 }
diff --git a/portal.go b/portal.go
index b940b28..841884c 100644
--- a/portal.go
+++ b/portal.go
@@ -690,8 +690,27 @@ func (portal *Portal) handleDiscordMessageUpdate(user *User, msg *discordgo.Mess
 
 	intent := portal.bridge.GetPuppetByID(msg.Author.ID).IntentFor(portal)
 
+	attachmentMap := map[string]*database.Message{}
+	for _, existingPart := range existing {
+		if existingPart.AttachmentID != "" {
+			attachmentMap[existingPart.AttachmentID] = existingPart
+		}
+	}
+	for _, attachment := range msg.Attachments {
+		if _, found := attachmentMap[attachment.ID]; found {
+			delete(attachmentMap, attachment.ID)
+		}
+	}
+	for _, attachment := range attachmentMap {
+		_, err := intent.RedactEvent(portal.MXID, attachment.MXID)
+		if err != nil {
+			portal.log.Warnfln("Failed to remove attachment %s: %v", attachment.MXID, err)
+		}
+		attachment.Delete()
+	}
+
 	if msg.Content == "" || existing[0].AttachmentID != "" {
-		portal.log.Debugfln("Dropping non-text edit to %s", msg.ID)
+		portal.log.Debugfln("Dropping non-text edit to %s (message on matrix: %t, text on discord: %t)", msg.ID, existing[0].AttachmentID == "", len(msg.Content) > 0)
 		return
 	}
 	content := renderDiscordMarkdown(msg.Content)
@@ -1297,6 +1316,7 @@ func (portal *Portal) handleMatrixRedaction(sender *User, evt *event.Event) {
 			portal.log.Debugfln("Failed to delete discord message %s: %v", message.DiscordID, err)
 			portal.bridge.SendMessageErrorCheckpoint(evt, bridge.MsgStepRemote, err, true, 0)
 		} else {
+			// TODO add support for deleting individual attachments from messages
 			message.Delete()
 			portal.bridge.SendMessageSuccessCheckpoint(evt, bridge.MsgStepRemote, 0)
 			portal.sendDeliveryReceipt(evt.ID)