From e3aed76f7ae3a66011ae9054d90b1f349cb1e8ac Mon Sep 17 00:00:00 2001
From: Tulir Asokan <tulir@maunium.net>
Date: Sat, 30 Oct 2021 21:54:35 +0300
Subject: [PATCH] Add option to limit age of chats to create portals for

---
 commands.go         |  2 +-
 config/bridge.go    | 12 +++++++-----
 example-config.yaml |  2 ++
 user.go             | 10 +++++++++-
 4 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/commands.go b/commands.go
index 741d96a..fb97f7b 100644
--- a/commands.go
+++ b/commands.go
@@ -720,7 +720,7 @@ func (handler *CommandHandler) CommandDeleteAllPortals(ce *CommandEvent) {
 	var portalsToDelete []*Portal
 
 	if ce.User.Admin {
-		portals = portalsToDelete
+		portalsToDelete = portals
 	} else {
 		portalsToDelete = portals[:0]
 		for _, portal := range portals {
diff --git a/config/bridge.go b/config/bridge.go
index bf1d367..83aa1e5 100644
--- a/config/bridge.go
+++ b/config/bridge.go
@@ -31,8 +31,8 @@ type BridgeConfig struct {
 	UsernameTemplate    string `yaml:"username_template"`
 	DisplaynameTemplate string `yaml:"displayname_template"`
 
-	DeliveryReceipts      bool `yaml:"delivery_receipts"`
-	PortalMessageBuffer   int  `yaml:"portal_message_buffer"`
+	DeliveryReceipts    bool `yaml:"delivery_receipts"`
+	PortalMessageBuffer int  `yaml:"portal_message_buffer"`
 
 	CallNotices struct {
 		Start bool `yaml:"start"`
@@ -40,9 +40,10 @@ type BridgeConfig struct {
 	} `yaml:"call_notices"`
 
 	HistorySync struct {
-		CreatePortals        bool `yaml:"create_portals"`
-		Backfill             bool `yaml:"backfill"`
-		DoublePuppetBackfill bool `yaml:"double_puppet_backfill"`
+		CreatePortals        bool  `yaml:"create_portals"`
+		MaxAge               int64 `yaml:"max_age"`
+		Backfill             bool  `yaml:"backfill"`
+		DoublePuppetBackfill bool  `yaml:"double_puppet_backfill"`
 	} `yaml:"history_sync"`
 	UserAvatarSync    bool `yaml:"user_avatar_sync"`
 	BridgeMatrixLeave bool `yaml:"bridge_matrix_leave"`
@@ -102,6 +103,7 @@ func (bc *BridgeConfig) setDefaults() {
 	bc.CallNotices.End = true
 
 	bc.HistorySync.CreatePortals = true
+	bc.HistorySync.MaxAge = 604800
 	bc.UserAvatarSync = true
 	bc.BridgeMatrixLeave = true
 
diff --git a/example-config.yaml b/example-config.yaml
index e2d84f4..24a7719 100644
--- a/example-config.yaml
+++ b/example-config.yaml
@@ -98,6 +98,8 @@ bridge:
     history_sync:
         # Whether to create portals from history sync payloads from WhatsApp.
         create_portals: true
+        # Maximum age of chats in seconds to create portals for. Set to 0 to create portals for all chats in sync payload.
+        max_age: 604800
         # Whether to enable backfilling history sync payloads from WhatsApp using batch sending
         # This requires a server with MSC2716 support, which is currently an experimental feature in synapse.
         # It can be enabled by setting experimental_features -> enable_msc2716 to true in homeserver.yaml.
diff --git a/user.go b/user.go
index 7778eab..795962a 100644
--- a/user.go
+++ b/user.go
@@ -347,6 +347,9 @@ func (user *User) handleHistorySync(evt *waProto.HistorySync) {
 		return
 	}
 	user.log.Infofln("Handling history sync with type %s, chunk order %d, progress %d%%", evt.GetSyncType(), evt.GetChunkOrder(), evt.GetProgress())
+	maxAge := user.bridge.Config.Bridge.HistorySync.MaxAge
+	minLastMsgToCreate := time.Now().Add(-time.Duration(maxAge) * time.Second)
+	createRooms := user.bridge.Config.Bridge.HistorySync.CreatePortals
 	for _, conv := range evt.GetConversations() {
 		jid, err := types.ParseJID(conv.GetId())
 		if err != nil {
@@ -365,8 +368,13 @@ func (user *User) handleHistorySync(evt *waProto.HistorySync) {
 			_ = user.Client.Store.ChatSettings.PutPinned(jid, true)
 		}
 
+		lastMsg := time.Unix(int64(conv.GetConversationTimestamp()), 0)
 		portal := user.GetPortalByJID(jid)
-		if user.bridge.Config.Bridge.HistorySync.CreatePortals && len(portal.MXID) == 0 {
+		if createRooms && len(portal.MXID) == 0 {
+			if maxAge > 0 && !lastMsg.After(minLastMsgToCreate) {
+				user.log.Debugfln("Not creating portal for %s: last message older than limit (%s)", portal.Key.JID, lastMsg)
+				continue
+			}
 			user.log.Debugln("Creating portal for", portal.Key.JID, "as part of history sync handling")
 			err = portal.CreateMatrixRoom(user)
 			if err != nil {