Add basic Matrix puppeting support

May contain bugs.
EDUs from /sync are not yet handled.

custompuppet.go

@@ -0,0 +1,168 @@
+// mautrix-whatsapp - A Matrix-WhatsApp puppeting bridge.
+// Copyright (C) 2019 Tulir Asokan
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/pkg/errors"
+	"maunium.net/go/mautrix"
+	"maunium.net/go/mautrix-appservice"
+)
+
+var (
+	ErrNoCustomMXID = errors.New("no custom mxid set")
+	ErrMismatchingMXID = errors.New("whoami result does not match custom mxid")
+)
+
+func (puppet *Puppet) SwitchCustomMXID(accessToken string, mxid string) error {
+	prevCustomMXID := puppet.CustomMXID
+	if puppet.customIntent != nil {
+		puppet.stopSyncing()
+	}
+	puppet.CustomMXID = mxid
+	puppet.AccessToken = accessToken
+
+	err := puppet.StartCustomMXID()
+	if err != nil {
+		return err
+	}
+
+	if len(prevCustomMXID) > 0 {
+		delete(puppet.bridge.puppetsByCustomMXID, prevCustomMXID)
+	}
+	if len(puppet.CustomMXID) > 0 {
+		puppet.bridge.puppetsByCustomMXID[puppet.CustomMXID] = puppet
+	}
+	puppet.Update()
+	// TODO leave rooms with default puppet
+	return nil
+}
+
+func (puppet *Puppet) newCustomIntent() (*appservice.IntentAPI, error) {
+	if len(puppet.CustomMXID) == 0 {
+		return nil, ErrNoCustomMXID
+	}
+	client, err := mautrix.NewClient(puppet.bridge.AS.HomeserverURL, puppet.CustomMXID, puppet.AccessToken)
+	if err != nil {
+		return nil, err
+	}
+	client.Store = puppet
+
+	ia := puppet.bridge.AS.NewIntentAPI("custom")
+	ia.Client = client
+	ia.Localpart = puppet.CustomMXID[1:strings.IndexRune(puppet.CustomMXID, ':')]
+	ia.UserID = puppet.CustomMXID
+	ia.IsCustomPuppet = true
+	return ia, nil
+}
+
+func (puppet *Puppet) StartCustomMXID() error {
+	if len(puppet.CustomMXID) == 0 {
+		return nil
+	}
+	intent, err := puppet.newCustomIntent()
+	if err != nil {
+		puppet.CustomMXID = ""
+		puppet.AccessToken = ""
+		return err
+	}
+	urlPath := intent.BuildURL("account", "whoami")
+	var resp struct{ UserID string `json:"user_id"` }
+	_, err = intent.MakeRequest("GET", urlPath, nil, &resp)
+	if err != nil {
+		puppet.CustomMXID = ""
+		puppet.AccessToken = ""
+		return err
+	}
+	if resp.UserID != puppet.CustomMXID {
+		puppet.CustomMXID = ""
+		puppet.AccessToken = ""
+		return ErrMismatchingMXID
+	}
+	puppet.customIntent = intent
+	puppet.startSyncing()
+	return nil
+}
+
+func (puppet *Puppet) startSyncing() {
+	if !puppet.bridge.Config.Bridge.SyncWithCustomPuppets {
+		return
+	}
+	go func() {
+		puppet.log.Debugln("Starting syncing...")
+		err := puppet.customIntent.Sync()
+		if err != nil {
+			puppet.log.Errorln("Fatal error syncing:", err)
+		}
+	}()
+}
+
+func (puppet *Puppet) stopSyncing() {
+	if !puppet.bridge.Config.Bridge.SyncWithCustomPuppets {
+		return
+	}
+	puppet.customIntent.StopSync()
+}
+
+func (puppet *Puppet) ProcessResponse(resp *mautrix.RespSync, since string) error {
+	puppet.log.Debugln("Sync data:", resp, since)
+	// TODO handle sync data
+	return nil
+}
+
+func (puppet *Puppet) OnFailedSync(res *mautrix.RespSync, err error) (time.Duration, error) {
+	puppet.log.Warnln("Sync error:", err)
+	return 10 * time.Second, nil
+}
+
+func (puppet *Puppet) GetFilterJSON(_ string) json.RawMessage {
+	mxid, _ := json.Marshal(puppet.CustomMXID)
+	return json.RawMessage(fmt.Sprintf(`{
+    "account_data": { "types": [] },
+    "presence": {
+        "senders": [
+            %s
+	    ],
+        "types": [
+            "m.presence"
+        ]
+    },
+    "room": {
+        "ephemeral": {
+            "types": [
+                "m.typing",
+                "m.receipt"
+            ]
+        },
+        "include_leave": false,
+        "account_data": { "types": [] },
+        "state": { "types": [] },
+        "timeline": { "types": [] }
+    }
+}`, mxid))
+}
+
+func (puppet *Puppet) SaveFilterID(_, _ string)             {}
+func (puppet *Puppet) SaveNextBatch(_, nbt string)          { puppet.NextBatch = nbt }
+func (puppet *Puppet) SaveRoom(room *mautrix.Room)          {}
+func (puppet *Puppet) LoadFilterID(_ string) string         { return "" }
+func (puppet *Puppet) LoadNextBatch(_ string) string        { return puppet.NextBatch }
+func (puppet *Puppet) LoadRoom(roomID string) *mautrix.Room { return nil }