From b1f3c4c1db36c5d317e9728a18ad31e5cdfc7c7d Mon Sep 17 00:00:00 2001
From: Conan <me@1conan.com>
Date: Tue, 7 Oct 2025 21:26:10 +0800
Subject: [PATCH] handlematrix: Implement DeleteChatHandlingNetworkAPI (#122)

---
 pkg/connector/capabilities.go | 10 ++++++++--
 pkg/connector/client.go       | 27 +++++++++++++++++++++++++++
 pkg/connector/handlematrix.go |  1 +
 3 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/pkg/connector/capabilities.go b/pkg/connector/capabilities.go
index 7a2a7c58..e8c9a2d5 100644
--- a/pkg/connector/capabilities.go
+++ b/pkg/connector/capabilities.go
@@ -26,6 +26,7 @@ import (
 	"go.mau.fi/util/ptr"
 	"go.mau.fi/util/variationselector"
 	"maunium.net/go/mautrix/bridgev2"
+	"maunium.net/go/mautrix/bridgev2/database"
 	"maunium.net/go/mautrix/event"
 )
 
@@ -57,7 +58,7 @@ func (tg *TelegramConnector) GetCapabilities() *bridgev2.NetworkGeneralCapabilit
 }
 
 func (tg *TelegramConnector) GetBridgeInfoVersion() (info, capabilities int) {
-	return 1, 5
+	return 1, 6
 }
 
 // TODO get these from getConfig instead of hardcoding?
@@ -207,7 +208,7 @@ func makeTimerList() []jsontime.Milliseconds {
 var telegramTimers = makeTimerList()
 
 func (t *TelegramClient) GetCapabilities(ctx context.Context, portal *bridgev2.Portal) *event.RoomFeatures {
-	baseID := "fi.mau.telegram.capabilities.2025_09_16"
+	baseID := "fi.mau.telegram.capabilities.2025_09_27"
 	feat := &event.RoomFeatures{
 		Formatting:          formattingCaps,
 		File:                fileCaps,
@@ -250,6 +251,11 @@ func (t *TelegramClient) GetCapabilities(ctx context.Context, portal *bridgev2.P
 		feat.File = premiumFileCaps
 		feat.ReactionCount = 3
 	}
+	if portal.RoomType == database.RoomTypeDM {
+		baseID += "+dm"
+		feat.DeleteChat = true
+		feat.DeleteChatForEveryone = true
+	}
 	feat.ID = baseID
 	return feat
 }
diff --git a/pkg/connector/client.go b/pkg/connector/client.go
index 3ad406af..f7b8030f 100644
--- a/pkg/connector/client.go
+++ b/pkg/connector/client.go
@@ -741,3 +741,30 @@ func (t *TelegramClient) senderForUserID(userID int64) bridgev2.EventSender {
 		Sender:      ids.MakeUserID(userID),
 	}
 }
+
+func (t *TelegramClient) HandleMatrixDeleteChat(ctx context.Context, chat *bridgev2.MatrixDeleteChat) error {
+	peerType, id, err := ids.ParsePortalID(chat.Portal.ID)
+	if err != nil {
+		return err
+	}
+	switch peerType {
+	case ids.PeerTypeUser:
+		if chat.Content.DeleteForEveryone {
+			_, err := t.client.API().MessagesDeleteHistory(ctx, &tg.MessagesDeleteHistoryRequest{
+				Peer:   &tg.InputPeerUser{UserID: id},
+				Revoke: true,
+				MaxID:  0,
+			})
+			if err != nil {
+				return err
+			}
+		}
+		_, err = t.client.API().MessagesDeleteChat(ctx, id)
+		if err != nil {
+			return err
+		}
+	default:
+		return fmt.Errorf("deleting chat not supported for peer type %s", peerType)
+	}
+	return nil
+}
diff --git a/pkg/connector/handlematrix.go b/pkg/connector/handlematrix.go
index ec75f663..d87e3a36 100644
--- a/pkg/connector/handlematrix.go
+++ b/pkg/connector/handlematrix.go
@@ -67,6 +67,7 @@ var (
 	_ bridgev2.MuteHandlingNetworkAPI           = (*TelegramClient)(nil)
 	_ bridgev2.TagHandlingNetworkAPI            = (*TelegramClient)(nil)
 	_ bridgev2.ChatViewingNetworkAPI            = (*TelegramClient)(nil)
+	_ bridgev2.DeleteChatHandlingNetworkAPI     = (*TelegramClient)(nil)
 )
 
 func getMediaFilename(content *event.MessageEventContent) (filename string) {