2 files changed, 43 insertions, 0 deletions
diff --git a/bridge/discord/discord.go b/bridge/discord/discord.go
index a59735ad..614512f3 100644
--- a/bridge/discord/discord.go
+++ b/bridge/discord/discord.go
@@ -34,6 +34,8 @@ type Bdiscord struct {
 	membersMutex  sync.RWMutex
 	userMemberMap map[string]*discordgo.Member
 	nickMemberMap map[string]*discordgo.Member
+	webhookCache  map[string]string
+	webhookMutex  sync.RWMutex
 }
 
 func New(cfg *bridge.Config) bridge.Bridger {
@@ -41,6 +43,7 @@ func New(cfg *bridge.Config) bridge.Bridger {
 	b.userMemberMap = make(map[string]*discordgo.Member)
 	b.nickMemberMap = make(map[string]*discordgo.Member)
 	b.channelInfoMap = make(map[string]*config.ChannelInfo)
+	b.webhookCache = make(map[string]string)
 	if b.GetString("WebhookURL") != "" {
 		b.Log.Debug("Configuring Discord Incoming Webhook")
 		b.webhookID, b.webhookToken = b.splitURL(b.GetString("WebhookURL"))
@@ -188,6 +191,8 @@ func (b *Bdiscord) JoinChannel(channel config.ChannelInfo) error {
 func (b *Bdiscord) Send(msg config.Message) (string, error) {
 	b.Log.Debugf("=> Receiving %#v", msg)
 
+	origMsgID := msg.ID
+
 	channelID := b.getChannelID(msg.Channel)
 	if channelID == "" {
 		return "", fmt.Errorf("Could not find channelID for %v", msg.Channel)
@@ -230,6 +235,7 @@ func (b *Bdiscord) Send(msg config.Message) (string, error) {
 
 		// If we are editing a message, delete the old message
 		if msg.ID != "" {
+			msg.ID = b.getCacheID(msg.ID)
 			b.Log.Debugf("Deleting edited webhook message")
 			err := b.c.ChannelMessageDelete(channelID, msg.ID)
 			if err != nil {
@@ -273,6 +279,8 @@ func (b *Bdiscord) Send(msg config.Message) (string, error) {
 		if msg == nil {
 			return "", nil
 		}
+
+		b.updateCacheID(origMsgID, msg.ID)
 		return msg.ID, nil
 	}
 
@@ -283,6 +291,7 @@ func (b *Bdiscord) Send(msg config.Message) (string, error) {
 		if msg.ID == "" {
 			return "", nil
 		}
+		msg.ID = b.getCacheID(msg.ID)
 		err := b.c.ChannelMessageDelete(channelID, msg.ID)
 		return "", err
 	}
diff --git a/bridge/discord/helpers.go b/bridge/discord/helpers.go
index 9ef234c5..00592f3a 100644
--- a/bridge/discord/helpers.go
+++ b/bridge/discord/helpers.go
@@ -208,6 +208,40 @@ func (b *Bdiscord) splitURL(url string) (string, string) {
 	return webhookURLSplit[webhookIdxID], webhookURLSplit[webhookIdxToken]
 }
 
+// getcacheID tries to find a corresponding msgID in the webhook cache.
+// if not found returns the original request.
+func (b *Bdiscord) getCacheID(msgID string) string {
+	b.webhookMutex.RLock()
+	defer b.webhookMutex.RUnlock()
+	for k, v := range b.webhookCache {
+		if msgID == k {
+			return v
+		}
+	}
+	return msgID
+}
+
+// updateCacheID updates the cache so that the newID takes the place of
+// the original ID. This is used for edit/deletes in combination with webhooks
+// as editing a message via webhook means deleting the message and creating a
+// new message (with a new ID). This ID needs to be set instead of the original ID
+func (b *Bdiscord) updateCacheID(origID, newID string) {
+	b.webhookMutex.Lock()
+	match := false
+	for k, v := range b.webhookCache {
+		if v == origID {
+			delete(b.webhookCache, k)
+			b.webhookCache[origID] = newID
+			match = true
+			continue
+		}
+	}
+	if !match && origID != "" {
+		b.webhookCache[origID] = newID
+	}
+	b.webhookMutex.Unlock()
+}
+
 func enumerateUsernames(s string) []string {
 	onlySpace := true
 	for _, r := range s {