From d501ce0578dec93cc3f5bcb6826f0bdc2ba7c930 Mon Sep 17 00:00:00 2001
From: Tulir Asokan <tulir@maunium.net>
Date: Mon, 10 Jun 2024 22:15:10 +0300
Subject: [PATCH] Add portal receiver to DMs

---
 go.mod                     |  2 +-
 go.sum                     |  4 ++--
 pkg/connector/connector.go | 45 +++++++++-----------------------------
 3 files changed, 13 insertions(+), 38 deletions(-)

diff --git a/go.mod b/go.mod
index 7d766d8a..c602f496 100644
--- a/go.mod
+++ b/go.mod
@@ -21,7 +21,7 @@ require (
 	golang.org/x/net v0.25.0
 	google.golang.org/protobuf v1.34.1
 	gopkg.in/yaml.v3 v3.0.1
-	maunium.net/go/mautrix v0.18.2-0.20240607095501-6466bf945260
+	maunium.net/go/mautrix v0.18.2-0.20240610191402-39ce0103d40b
 	nhooyr.io/websocket v1.8.11
 )
 
diff --git a/go.sum b/go.sum
index 78957fa7..f67f9ad4 100644
--- a/go.sum
+++ b/go.sum
@@ -95,7 +95,7 @@ gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 maunium.net/go/mauflag v1.0.0 h1:YiaRc0tEI3toYtJMRIfjP+jklH45uDHtT80nUamyD4M=
 maunium.net/go/mauflag v1.0.0/go.mod h1:nLivPOpTpHnpzEh8jEdSL9UqO9+/KBJFmNRlwKfkPeA=
-maunium.net/go/mautrix v0.18.2-0.20240607095501-6466bf945260 h1:PRjq8wEtssdiUhwVpo9h2LAlVEB04r3y/YR2XZsdlbg=
-maunium.net/go/mautrix v0.18.2-0.20240607095501-6466bf945260/go.mod h1:P/FV8cXY262MezYX7ViuhfzeJ0nK4+M8K6ZmxEC/aEA=
+maunium.net/go/mautrix v0.18.2-0.20240610191402-39ce0103d40b h1:sEwWJqdshbCZFGlvj6j3IPxBDznQLHG79GZdrMCEZvk=
+maunium.net/go/mautrix v0.18.2-0.20240610191402-39ce0103d40b/go.mod h1:P/FV8cXY262MezYX7ViuhfzeJ0nK4+M8K6ZmxEC/aEA=
 nhooyr.io/websocket v1.8.11 h1:f/qXNc2/3DpoSZkHt1DQu6rj4zGC8JmkkLkWss0MgN0=
 nhooyr.io/websocket v1.8.11/go.mod h1:rN9OFWIUwuxg4fR5tELlYC04bXYowCP9GX47ivo2l+c=
diff --git a/pkg/connector/connector.go b/pkg/connector/connector.go
index 69ec6b35..180a30e9 100644
--- a/pkg/connector/connector.go
+++ b/pkg/connector/connector.go
@@ -28,7 +28,6 @@ import (
 	"github.com/rs/zerolog"
 	"go.mau.fi/util/dbutil"
 	"go.mau.fi/util/variationselector"
-	"golang.org/x/exp/slices"
 	"google.golang.org/protobuf/proto"
 
 	"maunium.net/go/mautrix/bridgev2"
@@ -345,43 +344,14 @@ func parseUserID(userID networkid.UserID) (uuid.UUID, error) {
 }
 
 func (s *SignalClient) parsePortalID(portalID networkid.PortalID) (userID libsignalgo.ServiceID, groupID types.GroupIdentifier, err error) {
-	parts := strings.Split(string(portalID), "|")
-	if len(parts) == 1 {
-		if len(parts[0]) == 44 {
-			groupID = types.GroupIdentifier(parts[0])
-		} else {
-			err = fmt.Errorf("invalid portal ID: expected group ID to be 44 characters")
-		}
-	} else if len(parts) == 2 {
-		ourACI := s.Client.Store.ACI.String()
-		if parts[0] == ourACI {
-			userID, err = libsignalgo.ServiceIDFromString(parts[1])
-		} else if parts[1] == ourACI {
-			userID, err = libsignalgo.ServiceIDFromString(parts[0])
-		} else {
-			err = fmt.Errorf("invalid portal ID: expected one side to be our ACI")
-		}
+	if len(portalID) == 44 {
+		groupID = types.GroupIdentifier(portalID)
 	} else {
-		err = fmt.Errorf("invalid portal ID: unexpected number of pipe-separated parts")
+		userID, err = libsignalgo.ServiceIDFromString(string(portalID))
 	}
 	return
 }
 
-func (s *SignalClient) getPortalID(chatID string) networkid.PortalID {
-	if len(chatID) == 44 {
-		// Group ID
-		return networkid.PortalID(chatID)
-	} else if strings.HasPrefix(chatID, "PNI:") {
-		// Temporary new DM ID: always put our own ACI first, the portal will never be shared anyway
-		return networkid.PortalID(fmt.Sprintf("%s|%s", s.Client.Store.ACI, chatID))
-	} else {
-		// DM ID: sort the two parts so the ID is always the same regardless of which side is receiving the message
-		parts := []string{s.Client.Store.ACI.String(), chatID}
-		slices.Sort(parts)
-		return networkid.PortalID(strings.Join(parts, "|"))
-	}
-}
-
 func parseMessageID(messageID networkid.MessageID) (sender uuid.UUID, timestamp uint64, err error) {
 	parts := strings.Split(string(messageID), "|")
 	if len(parts) != 2 {
@@ -471,8 +441,13 @@ func (evt *Bv2ChatEvent) GetType() bridgev2.RemoteEventType {
 	return bridgev2.RemoteEventUnknown
 }
 
-func (evt *Bv2ChatEvent) GetPortalID() networkid.PortalID {
-	return evt.s.getPortalID(evt.Info.ChatID)
+func (evt *Bv2ChatEvent) GetPortalKey() networkid.PortalKey {
+	key := networkid.PortalKey{ID: networkid.PortalID(evt.Info.ChatID)}
+	// For non-group chats, add receiver
+	if len(evt.Info.ChatID) != 44 {
+		key.Receiver = makeUserLoginID(evt.s.Client.Store.ACI)
+	}
+	return key
 }
 
 func (evt *Bv2ChatEvent) ShouldCreatePortal() bool {