]> nmode's Git Repositories - signal-cli/blobdiff - lib/src/main/java/org/asamk/signal/manager/Manager.java
Split receiveMessages method
[signal-cli] / lib / src / main / java / org / asamk / signal / manager / Manager.java
index 60263dd996f40232503b24008aae011de4af1f3f..ac0cc02fc03aa98017798236ef3cabbfbf06bcfe 100644 (file)
-/*
-  Copyright (C) 2015-2021 AsamK and contributors
-
-  This program is free software: you can redistribute it and/or modify
-  it under the terms of the GNU 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 General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
 package org.asamk.signal.manager;
 
+import org.asamk.signal.manager.api.Device;
+import org.asamk.signal.manager.api.Group;
+import org.asamk.signal.manager.api.Identity;
+import org.asamk.signal.manager.api.Message;
+import org.asamk.signal.manager.api.RecipientIdentifier;
+import org.asamk.signal.manager.api.SendGroupMessageResults;
+import org.asamk.signal.manager.api.SendMessageResults;
+import org.asamk.signal.manager.api.TypingAction;
+import org.asamk.signal.manager.api.UpdateGroup;
 import org.asamk.signal.manager.config.ServiceConfig;
 import org.asamk.signal.manager.config.ServiceEnvironment;
-import org.asamk.signal.manager.config.ServiceEnvironmentConfig;
 import org.asamk.signal.manager.groups.GroupId;
-import org.asamk.signal.manager.groups.GroupIdV1;
 import org.asamk.signal.manager.groups.GroupInviteLinkUrl;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
-import org.asamk.signal.manager.groups.GroupUtils;
+import org.asamk.signal.manager.groups.GroupSendingNotAllowedException;
+import org.asamk.signal.manager.groups.LastGroupAdminException;
 import org.asamk.signal.manager.groups.NotAGroupMemberException;
-import org.asamk.signal.manager.helper.GroupHelper;
-import org.asamk.signal.manager.helper.PinHelper;
-import org.asamk.signal.manager.helper.ProfileHelper;
-import org.asamk.signal.manager.helper.UnidentifiedAccessHelper;
 import org.asamk.signal.manager.storage.SignalAccount;
-import org.asamk.signal.manager.storage.contacts.ContactInfo;
-import org.asamk.signal.manager.storage.groups.GroupInfo;
-import org.asamk.signal.manager.storage.groups.GroupInfoV1;
-import org.asamk.signal.manager.storage.groups.GroupInfoV2;
-import org.asamk.signal.manager.storage.identities.IdentityInfo;
-import org.asamk.signal.manager.storage.messageCache.CachedMessage;
-import org.asamk.signal.manager.storage.profiles.SignalProfile;
-import org.asamk.signal.manager.storage.recipients.RecipientId;
-import org.asamk.signal.manager.storage.stickers.Sticker;
-import org.asamk.signal.manager.util.AttachmentUtils;
-import org.asamk.signal.manager.util.IOUtils;
-import org.asamk.signal.manager.util.KeyUtils;
-import org.asamk.signal.manager.util.ProfileUtils;
-import org.asamk.signal.manager.util.StickerUtils;
-import org.asamk.signal.manager.util.Utils;
-import org.signal.libsignal.metadata.InvalidMetadataMessageException;
-import org.signal.libsignal.metadata.InvalidMetadataVersionException;
-import org.signal.libsignal.metadata.ProtocolDuplicateMessageException;
-import org.signal.libsignal.metadata.ProtocolInvalidKeyException;
-import org.signal.libsignal.metadata.ProtocolInvalidKeyIdException;
-import org.signal.libsignal.metadata.ProtocolInvalidMessageException;
-import org.signal.libsignal.metadata.ProtocolInvalidVersionException;
-import org.signal.libsignal.metadata.ProtocolLegacyMessageException;
-import org.signal.libsignal.metadata.ProtocolNoSessionException;
-import org.signal.libsignal.metadata.ProtocolUntrustedIdentityException;
-import org.signal.libsignal.metadata.SelfSendException;
-import org.signal.libsignal.metadata.certificate.CertificateValidator;
-import org.signal.storageservice.protos.groups.GroupChange;
-import org.signal.storageservice.protos.groups.local.DecryptedGroup;
-import org.signal.zkgroup.InvalidInputException;
-import org.signal.zkgroup.VerificationFailedException;
-import org.signal.zkgroup.groups.GroupMasterKey;
-import org.signal.zkgroup.groups.GroupSecretParams;
-import org.signal.zkgroup.profiles.ClientZkProfileOperations;
-import org.signal.zkgroup.profiles.ProfileKey;
-import org.signal.zkgroup.profiles.ProfileKeyCredential;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.whispersystems.libsignal.IdentityKey;
-import org.whispersystems.libsignal.IdentityKeyPair;
+import org.asamk.signal.manager.storage.identities.TrustNewIdentity;
+import org.asamk.signal.manager.storage.recipients.Contact;
+import org.asamk.signal.manager.storage.recipients.Profile;
+import org.asamk.signal.manager.storage.recipients.RecipientAddress;
 import org.whispersystems.libsignal.InvalidKeyException;
-import org.whispersystems.libsignal.InvalidMessageException;
-import org.whispersystems.libsignal.ecc.ECPublicKey;
-import org.whispersystems.libsignal.state.PreKeyRecord;
-import org.whispersystems.libsignal.state.SignedPreKeyRecord;
 import org.whispersystems.libsignal.util.Pair;
 import org.whispersystems.libsignal.util.guava.Optional;
-import org.whispersystems.signalservice.api.SignalServiceAccountManager;
-import org.whispersystems.signalservice.api.SignalServiceMessagePipe;
-import org.whispersystems.signalservice.api.SignalServiceMessageReceiver;
-import org.whispersystems.signalservice.api.SignalServiceMessageSender;
-import org.whispersystems.signalservice.api.crypto.SignalServiceCipher;
-import org.whispersystems.signalservice.api.crypto.UntrustedIdentityException;
-import org.whispersystems.signalservice.api.groupsv2.ClientZkOperations;
 import org.whispersystems.signalservice.api.groupsv2.GroupLinkNotActiveException;
-import org.whispersystems.signalservice.api.groupsv2.GroupsV2Api;
-import org.whispersystems.signalservice.api.groupsv2.GroupsV2AuthorizationString;
-import org.whispersystems.signalservice.api.groupsv2.GroupsV2Operations;
-import org.whispersystems.signalservice.api.messages.SendMessageResult;
-import org.whispersystems.signalservice.api.messages.SignalServiceAttachment;
-import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentPointer;
 import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentRemoteId;
-import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentStream;
 import org.whispersystems.signalservice.api.messages.SignalServiceContent;
-import org.whispersystems.signalservice.api.messages.SignalServiceDataMessage;
 import org.whispersystems.signalservice.api.messages.SignalServiceEnvelope;
-import org.whispersystems.signalservice.api.messages.SignalServiceGroup;
-import org.whispersystems.signalservice.api.messages.SignalServiceGroupV2;
-import org.whispersystems.signalservice.api.messages.SignalServiceReceiptMessage;
-import org.whispersystems.signalservice.api.messages.multidevice.BlockedListMessage;
-import org.whispersystems.signalservice.api.messages.multidevice.ContactsMessage;
-import org.whispersystems.signalservice.api.messages.multidevice.DeviceContact;
-import org.whispersystems.signalservice.api.messages.multidevice.DeviceContactsInputStream;
-import org.whispersystems.signalservice.api.messages.multidevice.DeviceContactsOutputStream;
-import org.whispersystems.signalservice.api.messages.multidevice.DeviceGroup;
-import org.whispersystems.signalservice.api.messages.multidevice.DeviceGroupsInputStream;
-import org.whispersystems.signalservice.api.messages.multidevice.DeviceGroupsOutputStream;
-import org.whispersystems.signalservice.api.messages.multidevice.DeviceInfo;
-import org.whispersystems.signalservice.api.messages.multidevice.RequestMessage;
-import org.whispersystems.signalservice.api.messages.multidevice.SentTranscriptMessage;
-import org.whispersystems.signalservice.api.messages.multidevice.SignalServiceSyncMessage;
-import org.whispersystems.signalservice.api.messages.multidevice.StickerPackOperationMessage;
-import org.whispersystems.signalservice.api.messages.multidevice.VerifiedMessage;
-import org.whispersystems.signalservice.api.profiles.ProfileAndCredential;
-import org.whispersystems.signalservice.api.profiles.SignalServiceProfile;
 import org.whispersystems.signalservice.api.push.SignalServiceAddress;
-import org.whispersystems.signalservice.api.push.exceptions.MissingConfigurationException;
-import org.whispersystems.signalservice.api.util.InvalidNumberException;
+import org.whispersystems.signalservice.api.push.exceptions.UnregisteredUserException;
 import org.whispersystems.signalservice.api.util.PhoneNumberFormatter;
-import org.whispersystems.signalservice.api.util.SleepTimer;
-import org.whispersystems.signalservice.api.util.UptimeSleepTimer;
-import org.whispersystems.signalservice.api.util.UuidUtil;
-import org.whispersystems.signalservice.internal.contacts.crypto.Quote;
-import org.whispersystems.signalservice.internal.contacts.crypto.UnauthenticatedQuoteException;
 import org.whispersystems.signalservice.internal.contacts.crypto.UnauthenticatedResponseException;
-import org.whispersystems.signalservice.internal.push.SignalServiceProtos;
-import org.whispersystems.signalservice.internal.push.UnsupportedDataMessageException;
-import org.whispersystems.signalservice.internal.util.DynamicCredentialsProvider;
-import org.whispersystems.signalservice.internal.util.Hex;
-import org.whispersystems.signalservice.internal.util.Util;
 
 import java.io.Closeable;
 import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
 import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
 import java.net.URI;
-import java.net.URISyntaxException;
-import java.net.URLEncoder;
-import java.nio.charset.StandardCharsets;
-import java.nio.file.Files;
-import java.security.SignatureException;
-import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collection;
-import java.util.Date;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.UUID;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
-import java.util.concurrent.TimeoutException;
-import java.util.function.Function;
 import java.util.stream.Collectors;
 
-import static org.asamk.signal.manager.config.ServiceConfig.capabilities;
-
-public class Manager implements Closeable {
-
-    private final static Logger logger = LoggerFactory.getLogger(Manager.class);
-
-    private final CertificateValidator certificateValidator;
-
-    private final ServiceEnvironmentConfig serviceEnvironmentConfig;
-    private final String userAgent;
-
-    private SignalAccount account;
-    private final SignalServiceAccountManager accountManager;
-    private final GroupsV2Api groupsV2Api;
-    private final GroupsV2Operations groupsV2Operations;
-    private final SignalServiceMessageReceiver messageReceiver;
-    private final ClientZkProfileOperations clientZkProfileOperations;
-
-    private final ExecutorService executor = Executors.newCachedThreadPool();
-
-    private SignalServiceMessagePipe messagePipe = null;
-    private SignalServiceMessagePipe unidentifiedMessagePipe = null;
-
-    private final UnidentifiedAccessHelper unidentifiedAccessHelper;
-    private final ProfileHelper profileHelper;
-    private final GroupHelper groupHelper;
-    private final PinHelper pinHelper;
-    private final AvatarStore avatarStore;
-    private final AttachmentStore attachmentStore;
-
-    Manager(
-            SignalAccount account,
-            PathConfig pathConfig,
-            ServiceEnvironmentConfig serviceEnvironmentConfig,
-            String userAgent
-    ) {
-        this.account = account;
-        this.serviceEnvironmentConfig = serviceEnvironmentConfig;
-        this.certificateValidator = new CertificateValidator(serviceEnvironmentConfig.getUnidentifiedSenderTrustRoot());
-        this.userAgent = userAgent;
-        this.groupsV2Operations = capabilities.isGv2() ? new GroupsV2Operations(ClientZkOperations.create(
-                serviceEnvironmentConfig.getSignalServiceConfiguration())) : null;
-        final SleepTimer timer = new UptimeSleepTimer();
-        this.accountManager = new SignalServiceAccountManager(serviceEnvironmentConfig.getSignalServiceConfiguration(),
-                new DynamicCredentialsProvider(account.getUuid(),
-                        account.getUsername(),
-                        account.getPassword(),
-                        account.getDeviceId()),
-                userAgent,
-                groupsV2Operations,
-                ServiceConfig.AUTOMATIC_NETWORK_RETRY,
-                timer);
-        this.groupsV2Api = accountManager.getGroupsV2Api();
-        final var keyBackupService = accountManager.getKeyBackupService(ServiceConfig.getIasKeyStore(),
-                serviceEnvironmentConfig.getKeyBackupConfig().getEnclaveName(),
-                serviceEnvironmentConfig.getKeyBackupConfig().getServiceId(),
-                serviceEnvironmentConfig.getKeyBackupConfig().getMrenclave(),
-                10);
-
-        this.pinHelper = new PinHelper(keyBackupService);
-        this.clientZkProfileOperations = capabilities.isGv2()
-                ? ClientZkOperations.create(serviceEnvironmentConfig.getSignalServiceConfiguration())
-                .getProfileOperations()
-                : null;
-        this.messageReceiver = new SignalServiceMessageReceiver(serviceEnvironmentConfig.getSignalServiceConfiguration(),
-                account.getUuid(),
-                account.getUsername(),
-                account.getPassword(),
-                account.getDeviceId(),
-                userAgent,
-                null,
-                timer,
-                clientZkProfileOperations,
-                ServiceConfig.AUTOMATIC_NETWORK_RETRY);
-
-        this.unidentifiedAccessHelper = new UnidentifiedAccessHelper(account::getProfileKey,
-                account.getProfileStore()::getProfileKey,
-                this::getRecipientProfile,
-                this::getSenderCertificate);
-        this.profileHelper = new ProfileHelper(account.getProfileStore()::getProfileKey,
-                unidentifiedAccessHelper::getAccessFor,
-                unidentified -> unidentified ? getOrCreateUnidentifiedMessagePipe() : getOrCreateMessagePipe(),
-                () -> messageReceiver);
-        this.groupHelper = new GroupHelper(this::getRecipientProfileKeyCredential,
-                this::getRecipientProfile,
-                account::getSelfAddress,
-                groupsV2Operations,
-                groupsV2Api,
-                this::getGroupAuthForToday);
-        this.avatarStore = new AvatarStore(pathConfig.getAvatarsPath());
-        this.attachmentStore = new AttachmentStore(pathConfig.getAttachmentsPath());
-    }
-
-    public String getUsername() {
-        return account.getUsername();
-    }
-
-    public SignalServiceAddress getSelfAddress() {
-        return account.getSelfAddress();
-    }
-
-    private IdentityKeyPair getIdentityKeyPair() {
-        return account.getIdentityKeyPair();
-    }
-
-    public int getDeviceId() {
-        return account.getDeviceId();
-    }
+public interface Manager extends Closeable {
 
-    public static Manager init(
-            String username, File settingsPath, ServiceEnvironment serviceEnvironment, String userAgent
+    static Manager init(
+            String number,
+            File settingsPath,
+            ServiceEnvironment serviceEnvironment,
+            String userAgent,
+            TrustNewIdentity trustNewIdentity
     ) throws IOException, NotRegisteredException {
         var pathConfig = PathConfig.createDefault(settingsPath);
 
-        if (!SignalAccount.userExists(pathConfig.getDataPath(), username)) {
+        if (!SignalAccount.userExists(pathConfig.getDataPath(), number)) {
             throw new NotRegisteredException();
         }
 
-        var account = SignalAccount.load(pathConfig.getDataPath(), username);
+        var account = SignalAccount.load(pathConfig.getDataPath(), number, true, trustNewIdentity);
 
         if (!account.isRegistered()) {
             throw new NotRegisteredException();
@@ -286,10 +69,10 @@ public class Manager implements Closeable {
 
         final var serviceEnvironmentConfig = ServiceConfig.getServiceEnvironmentConfig(serviceEnvironment, userAgent);
 
-        return new Manager(account, pathConfig, serviceEnvironmentConfig, userAgent);
+        return new ManagerImpl(account, pathConfig, serviceEnvironmentConfig, userAgent);
     }
 
-    public static List<String> getAllLocalUsernames(File settingsPath) {
+    static List<String> getAllLocalNumbers(File settingsPath) {
         var pathConfig = PathConfig.createDefault(settingsPath);
         final var dataPath = pathConfig.getDataPath();
         final var files = dataPath.listFiles();
@@ -305,2227 +88,155 @@ public class Manager implements Closeable {
                 .collect(Collectors.toList());
     }
 
-    public void checkAccountState() throws IOException {
-        if (accountManager.getPreKeysCount() < ServiceConfig.PREKEY_MINIMUM_COUNT) {
-            refreshPreKeys();
-            account.save();
-        }
-        if (account.getUuid() == null) {
-            account.setUuid(accountManager.getOwnUuid());
-            account.save();
-        }
-        updateAccountAttributes();
-    }
-
-    /**
-     * This is used for checking a set of phone numbers for registration on Signal
-     *
-     * @param numbers The set of phone number in question
-     * @return A map of numbers to booleans. True if registered, false otherwise. Should never be null
-     * @throws IOException if its unable to get the contacts to check if they're registered
-     */
-    public Map<String, Boolean> areUsersRegistered(Set<String> numbers) throws IOException {
-        // Note "contactDetails" has no optionals. It only gives us info on users who are registered
-        var contactDetails = getRegisteredUsers(numbers);
-
-        var registeredUsers = contactDetails.keySet();
-
-        return numbers.stream().collect(Collectors.toMap(x -> x, registeredUsers::contains));
-    }
-
-    public void updateAccountAttributes() throws IOException {
-        accountManager.setAccountAttributes(null,
-                account.getLocalRegistrationId(),
-                true,
-                // set legacy pin only if no KBS master key is set
-                account.getPinMasterKey() == null ? account.getRegistrationLockPin() : null,
-                account.getPinMasterKey() == null ? null : account.getPinMasterKey().deriveRegistrationLock(),
-                account.getSelfUnidentifiedAccessKey(),
-                account.isUnrestrictedUnidentifiedAccess(),
-                capabilities,
-                account.isDiscoverableByPhoneNumber());
-    }
-
-    /**
-     * @param name       if null, the previous name will be kept
-     * @param about      if null, the previous about text will be kept
-     * @param aboutEmoji if null, the previous about emoji will be kept
-     * @param avatar     if avatar is null the image from the local avatar store is used (if present),
-     *                   if it's Optional.absent(), the avatar will be removed
-     */
-    public void setProfile(String name, String about, String aboutEmoji, Optional<File> avatar) throws IOException {
-        var profileEntry = account.getProfileStore().getProfileEntry(getSelfAddress());
-        var profile = profileEntry == null ? null : profileEntry.getProfile();
-        var newProfile = new SignalProfile(profile == null ? null : profile.getIdentityKey(),
-                name != null ? name : profile == null || profile.getName() == null ? "" : profile.getName(),
-                about != null ? about : profile == null || profile.getAbout() == null ? "" : profile.getAbout(),
-                aboutEmoji != null
-                        ? aboutEmoji
-                        : profile == null || profile.getAboutEmoji() == null ? "" : profile.getAboutEmoji(),
-                profile == null ? null : profile.getUnidentifiedAccess(),
-                account.isUnrestrictedUnidentifiedAccess(),
-                profile == null ? null : profile.getCapabilities());
-
-        try (final var streamDetails = avatar == null
-                ? avatarStore.retrieveProfileAvatar(getSelfAddress())
-                : avatar.isPresent() ? Utils.createStreamDetailsFromFile(avatar.get()) : null) {
-            accountManager.setVersionedProfile(account.getUuid(),
-                    account.getProfileKey(),
-                    newProfile.getName(),
-                    newProfile.getAbout(),
-                    newProfile.getAboutEmoji(),
-                    streamDetails);
-        }
-
-        if (avatar != null) {
-            if (avatar.isPresent()) {
-                avatarStore.storeProfileAvatar(getSelfAddress(),
-                        outputStream -> IOUtils.copyFileToStream(avatar.get(), outputStream));
-            } else {
-                avatarStore.deleteProfileAvatar(getSelfAddress());
-            }
-        }
-        account.getProfileStore()
-                .updateProfile(getSelfAddress(),
-                        account.getProfileKey(),
-                        System.currentTimeMillis(),
-                        newProfile,
-                        profileEntry == null ? null : profileEntry.getProfileKeyCredential());
-
-        try {
-            sendSyncMessage(SignalServiceSyncMessage.forFetchLatest(SignalServiceSyncMessage.FetchType.LOCAL_PROFILE));
-        } catch (UntrustedIdentityException ignored) {
-        }
-    }
-
-    public void unregister() throws IOException {
-        // When setting an empty GCM id, the Signal-Server also sets the fetchesMessages property to false.
-        // If this is the master device, other users can't send messages to this number anymore.
-        // If this is a linked device, other users can still send messages, but this device doesn't receive them anymore.
-        accountManager.setGcmId(Optional.absent());
-        accountManager.deleteAccount();
-
-        account.setRegistered(false);
-        account.save();
-    }
-
-    public List<DeviceInfo> getLinkedDevices() throws IOException {
-        var devices = accountManager.getDevices();
-        account.setMultiDevice(devices.size() > 1);
-        account.save();
-        return devices;
-    }
-
-    public void removeLinkedDevices(int deviceId) throws IOException {
-        accountManager.removeDevice(deviceId);
-        var devices = accountManager.getDevices();
-        account.setMultiDevice(devices.size() > 1);
-        account.save();
-    }
-
-    public void addDeviceLink(URI linkUri) throws IOException, InvalidKeyException {
-        var info = DeviceLinkInfo.parseDeviceLinkUri(linkUri);
-
-        addDevice(info.deviceIdentifier, info.deviceKey);
-    }
-
-    private void addDevice(String deviceIdentifier, ECPublicKey deviceKey) throws IOException, InvalidKeyException {
-        var identityKeyPair = getIdentityKeyPair();
-        var verificationCode = accountManager.getNewDeviceVerificationCode();
-
-        accountManager.addDevice(deviceIdentifier,
-                deviceKey,
-                identityKeyPair,
-                Optional.of(account.getProfileKey().serialize()),
-                verificationCode);
-        account.setMultiDevice(true);
-        account.save();
-    }
-
-    public void setRegistrationLockPin(Optional<String> pin) throws IOException, UnauthenticatedResponseException {
-        if (!account.isMasterDevice()) {
-            throw new RuntimeException("Only master device can set a PIN");
-        }
-        if (pin.isPresent()) {
-            final var masterKey = account.getPinMasterKey() != null
-                    ? account.getPinMasterKey()
-                    : KeyUtils.createMasterKey();
-
-            pinHelper.setRegistrationLockPin(pin.get(), masterKey);
-
-            account.setRegistrationLockPin(pin.get());
-            account.setPinMasterKey(masterKey);
-        } else {
-            // Remove legacy registration lock
-            accountManager.removeRegistrationLockV1();
-
-            // Remove KBS Pin
-            pinHelper.removeRegistrationLockPin();
-
-            account.setRegistrationLockPin(null);
-            account.setPinMasterKey(null);
-        }
-        account.save();
-    }
-
-    void refreshPreKeys() throws IOException {
-        var oneTimePreKeys = generatePreKeys();
-        final var identityKeyPair = getIdentityKeyPair();
-        var signedPreKeyRecord = generateSignedPreKey(identityKeyPair);
-
-        accountManager.setPreKeys(identityKeyPair.getPublicKey(), signedPreKeyRecord, oneTimePreKeys);
-    }
-
-    private List<PreKeyRecord> generatePreKeys() {
-        final var offset = account.getPreKeyIdOffset();
-
-        var records = KeyUtils.generatePreKeyRecords(offset, ServiceConfig.PREKEY_BATCH_SIZE);
-        account.addPreKeys(records);
-
-        return records;
-    }
-
-    private SignedPreKeyRecord generateSignedPreKey(IdentityKeyPair identityKeyPair) {
-        final var signedPreKeyId = account.getNextSignedPreKeyId();
-
-        var record = KeyUtils.generateSignedPreKeyRecord(identityKeyPair, signedPreKeyId);
-        account.addSignedPreKey(record);
-
-        return record;
-    }
-
-    private SignalServiceMessagePipe getOrCreateMessagePipe() {
-        if (messagePipe == null) {
-            messagePipe = messageReceiver.createMessagePipe();
-        }
-        return messagePipe;
-    }
-
-    private SignalServiceMessagePipe getOrCreateUnidentifiedMessagePipe() {
-        if (unidentifiedMessagePipe == null) {
-            unidentifiedMessagePipe = messageReceiver.createUnidentifiedMessagePipe();
-        }
-        return unidentifiedMessagePipe;
-    }
-
-    private SignalServiceMessageSender createMessageSender() {
-        return new SignalServiceMessageSender(serviceEnvironmentConfig.getSignalServiceConfiguration(),
-                account.getUuid(),
-                account.getUsername(),
-                account.getPassword(),
-                account.getDeviceId(),
-                account.getSignalProtocolStore(),
-                userAgent,
-                account.isMultiDevice(),
-                Optional.fromNullable(messagePipe),
-                Optional.fromNullable(unidentifiedMessagePipe),
-                Optional.absent(),
-                clientZkProfileOperations,
-                executor,
-                ServiceConfig.MAX_ENVELOPE_SIZE,
-                ServiceConfig.AUTOMATIC_NETWORK_RETRY);
-    }
-
-    public SignalProfile getRecipientProfile(
-            SignalServiceAddress address
-    ) {
-        return getRecipientProfile(address, false);
-    }
-
-    private SignalProfile getRecipientProfile(
-            SignalServiceAddress address, boolean force
-    ) {
-        var profileEntry = account.getProfileStore().getProfileEntry(address);
-        if (profileEntry == null) {
-            return null;
-        }
-        var now = new Date().getTime();
-        // Profiles are cached for 24h before retrieving them again
-        if (!profileEntry.isRequestPending() && (
-                force
-                        || profileEntry.getProfile() == null
-                        || now - profileEntry.getLastUpdateTimestamp() > 24 * 60 * 60 * 1000
-        )) {
-            profileEntry.setRequestPending(true);
-            final SignalServiceProfile encryptedProfile;
-            try {
-                encryptedProfile = profileHelper.retrieveProfileSync(address, SignalServiceProfile.RequestType.PROFILE)
-                        .getProfile();
-            } catch (IOException e) {
-                logger.warn("Failed to retrieve profile, ignoring: {}", e.getMessage());
-                return null;
-            } finally {
-                profileEntry.setRequestPending(false);
-            }
-
-            final var profileKey = profileEntry.getProfileKey();
-            final var profile = decryptProfileAndDownloadAvatar(address, profileKey, encryptedProfile);
-            account.getProfileStore()
-                    .updateProfile(address, profileKey, now, profile, profileEntry.getProfileKeyCredential());
-            return profile;
-        }
-        return profileEntry.getProfile();
-    }
-
-    private ProfileKeyCredential getRecipientProfileKeyCredential(SignalServiceAddress address) {
-        var profileEntry = account.getProfileStore().getProfileEntry(address);
-        if (profileEntry == null) {
-            return null;
-        }
-        if (profileEntry.getProfileKeyCredential() == null) {
-            ProfileAndCredential profileAndCredential;
-            try {
-                profileAndCredential = profileHelper.retrieveProfileSync(address,
-                        SignalServiceProfile.RequestType.PROFILE_AND_CREDENTIAL);
-            } catch (IOException e) {
-                logger.warn("Failed to retrieve profile key credential, ignoring: {}", e.getMessage());
-                return null;
-            }
-
-            var now = new Date().getTime();
-            final var profileKeyCredential = profileAndCredential.getProfileKeyCredential().orNull();
-            final var profile = decryptProfileAndDownloadAvatar(address,
-                    profileEntry.getProfileKey(),
-                    profileAndCredential.getProfile());
-            account.getProfileStore()
-                    .updateProfile(address, profileEntry.getProfileKey(), now, profile, profileKeyCredential);
-            return profileKeyCredential;
-        }
-        return profileEntry.getProfileKeyCredential();
-    }
-
-    private SignalProfile decryptProfileAndDownloadAvatar(
-            final SignalServiceAddress address, final ProfileKey profileKey, final SignalServiceProfile encryptedProfile
-    ) {
-        if (encryptedProfile.getAvatar() != null) {
-            downloadProfileAvatar(address, encryptedProfile.getAvatar(), profileKey);
-        }
-
-        return ProfileUtils.decryptProfile(profileKey, encryptedProfile);
-    }
-
-    private Optional<SignalServiceAttachmentStream> createGroupAvatarAttachment(GroupId groupId) throws IOException {
-        final var streamDetails = avatarStore.retrieveGroupAvatar(groupId);
-        if (streamDetails == null) {
-            return Optional.absent();
-        }
-
-        return Optional.of(AttachmentUtils.createAttachment(streamDetails, Optional.absent()));
-    }
-
-    private Optional<SignalServiceAttachmentStream> createContactAvatarAttachment(SignalServiceAddress address) throws IOException {
-        final var streamDetails = avatarStore.retrieveContactAvatar(address);
-        if (streamDetails == null) {
-            return Optional.absent();
-        }
-
-        return Optional.of(AttachmentUtils.createAttachment(streamDetails, Optional.absent()));
-    }
-
-    private GroupInfo getGroupForSending(GroupId groupId) throws GroupNotFoundException, NotAGroupMemberException {
-        var g = getGroup(groupId);
-        if (g == null) {
-            throw new GroupNotFoundException(groupId);
-        }
-        if (!g.isMember(account.getSelfAddress())) {
-            throw new NotAGroupMemberException(groupId, g.getTitle());
-        }
-        return g;
-    }
-
-    private GroupInfo getGroupForUpdating(GroupId groupId) throws GroupNotFoundException, NotAGroupMemberException {
-        var g = getGroup(groupId);
-        if (g == null) {
-            throw new GroupNotFoundException(groupId);
-        }
-        if (!g.isMember(account.getSelfAddress()) && !g.isPendingMember(account.getSelfAddress())) {
-            throw new NotAGroupMemberException(groupId, g.getTitle());
-        }
-        return g;
-    }
+    String getSelfNumber();
 
-    public List<GroupInfo> getGroups() {
-        return account.getGroupStore().getGroups();
-    }
+    void checkAccountState() throws IOException;
 
-    public Pair<Long, List<SendMessageResult>> sendGroupMessage(
-            String messageText, List<String> attachments, GroupId groupId
-    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException {
-        final var messageBuilder = SignalServiceDataMessage.newBuilder().withBody(messageText);
-        if (attachments != null) {
-            messageBuilder.withAttachments(AttachmentUtils.getSignalServiceAttachments(attachments));
-        }
+    Map<String, Pair<String, UUID>> areUsersRegistered(Set<String> numbers) throws IOException;
 
-        return sendGroupMessage(messageBuilder, groupId);
-    }
+    void updateAccountAttributes(String deviceName) throws IOException;
 
-    public Pair<Long, List<SendMessageResult>> sendGroupMessageReaction(
-            String emoji, boolean remove, String targetAuthor, long targetSentTimestamp, GroupId groupId
-    ) throws IOException, InvalidNumberException, NotAGroupMemberException, GroupNotFoundException {
-        var reaction = new SignalServiceDataMessage.Reaction(emoji,
-                remove,
-                canonicalizeAndResolveSignalServiceAddress(targetAuthor),
-                targetSentTimestamp);
-        final var messageBuilder = SignalServiceDataMessage.newBuilder().withReaction(reaction);
+    void updateConfiguration(
+            final Boolean readReceipts,
+            final Boolean unidentifiedDeliveryIndicators,
+            final Boolean typingIndicators,
+            final Boolean linkPreviews
+    ) throws IOException, NotMasterDeviceException;
 
-        return sendGroupMessage(messageBuilder, groupId);
-    }
+    void setProfile(
+            String givenName, String familyName, String about, String aboutEmoji, Optional<File> avatar
+    ) throws IOException;
 
-    public Pair<Long, List<SendMessageResult>> sendGroupMessage(
-            SignalServiceDataMessage.Builder messageBuilder, GroupId groupId
-    ) throws IOException, GroupNotFoundException, NotAGroupMemberException {
-        final var g = getGroupForSending(groupId);
+    void unregister() throws IOException;
 
-        GroupUtils.setGroupContext(messageBuilder, g);
-        messageBuilder.withExpiration(g.getMessageExpirationTime());
+    void deleteAccount() throws IOException;
 
-        return sendMessage(messageBuilder, g.getMembersWithout(account.getSelfAddress()));
-    }
+    void submitRateLimitRecaptchaChallenge(String challenge, String captcha) throws IOException;
 
-    public Pair<Long, List<SendMessageResult>> sendQuitGroupMessage(GroupId groupId) throws GroupNotFoundException, IOException, NotAGroupMemberException {
-        SignalServiceDataMessage.Builder messageBuilder;
-
-        final var g = getGroupForUpdating(groupId);
-        if (g instanceof GroupInfoV1) {
-            var groupInfoV1 = (GroupInfoV1) g;
-            var group = SignalServiceGroup.newBuilder(SignalServiceGroup.Type.QUIT).withId(groupId.serialize()).build();
-            messageBuilder = SignalServiceDataMessage.newBuilder().asGroupMessage(group);
-            groupInfoV1.removeMember(account.getSelfAddress());
-            account.getGroupStore().updateGroup(groupInfoV1);
-        } else {
-            final var groupInfoV2 = (GroupInfoV2) g;
-            final var groupGroupChangePair = groupHelper.leaveGroup(groupInfoV2);
-            groupInfoV2.setGroup(groupGroupChangePair.first());
-            messageBuilder = getGroupUpdateMessageBuilder(groupInfoV2, groupGroupChangePair.second().toByteArray());
-            account.getGroupStore().updateGroup(groupInfoV2);
-        }
+    List<Device> getLinkedDevices() throws IOException;
 
-        return sendMessage(messageBuilder, g.getMembersWithout(account.getSelfAddress()));
-    }
+    void removeLinkedDevices(long deviceId) throws IOException;
 
-    public Pair<GroupId, List<SendMessageResult>> updateGroup(
-            GroupId groupId, String name, List<String> members, File avatarFile
-    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, InvalidNumberException, NotAGroupMemberException {
-        return sendUpdateGroupMessage(groupId,
-                name,
-                members == null ? null : getSignalServiceAddresses(members),
-                avatarFile);
-    }
+    void addDeviceLink(URI linkUri) throws IOException, InvalidKeyException;
 
-    private Pair<GroupId, List<SendMessageResult>> sendUpdateGroupMessage(
-            GroupId groupId, String name, Collection<SignalServiceAddress> members, File avatarFile
-    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException {
-        GroupInfo g;
-        SignalServiceDataMessage.Builder messageBuilder;
-        if (groupId == null) {
-            // Create new group
-            var gv2 = groupHelper.createGroupV2(name == null ? "" : name,
-                    members == null ? List.of() : members,
-                    avatarFile);
-            if (gv2 == null) {
-                var gv1 = new GroupInfoV1(GroupIdV1.createRandom());
-                gv1.addMembers(List.of(account.getSelfAddress()));
-                updateGroupV1(gv1, name, members, avatarFile);
-                messageBuilder = getGroupUpdateMessageBuilder(gv1);
-                g = gv1;
-            } else {
-                if (avatarFile != null) {
-                    avatarStore.storeGroupAvatar(gv2.getGroupId(),
-                            outputStream -> IOUtils.copyFileToStream(avatarFile, outputStream));
-                }
-                messageBuilder = getGroupUpdateMessageBuilder(gv2, null);
-                g = gv2;
-            }
-        } else {
-            var group = getGroupForUpdating(groupId);
-            if (group instanceof GroupInfoV2) {
-                final var groupInfoV2 = (GroupInfoV2) group;
-
-                Pair<Long, List<SendMessageResult>> result = null;
-                if (groupInfoV2.isPendingMember(getSelfAddress())) {
-                    var groupGroupChangePair = groupHelper.acceptInvite(groupInfoV2);
-                    result = sendUpdateGroupMessage(groupInfoV2,
-                            groupGroupChangePair.first(),
-                            groupGroupChangePair.second());
-                }
-
-                if (members != null) {
-                    final var newMembers = new HashSet<>(members);
-                    newMembers.removeAll(group.getMembers()
-                            .stream()
-                            .map(this::resolveSignalServiceAddress)
-                            .collect(Collectors.toSet()));
-                    if (newMembers.size() > 0) {
-                        var groupGroupChangePair = groupHelper.updateGroupV2(groupInfoV2, newMembers);
-                        result = sendUpdateGroupMessage(groupInfoV2,
-                                groupGroupChangePair.first(),
-                                groupGroupChangePair.second());
-                    }
-                }
-                if (result == null || name != null || avatarFile != null) {
-                    var groupGroupChangePair = groupHelper.updateGroupV2(groupInfoV2, name, avatarFile);
-                    if (avatarFile != null) {
-                        avatarStore.storeGroupAvatar(groupInfoV2.getGroupId(),
-                                outputStream -> IOUtils.copyFileToStream(avatarFile, outputStream));
-                    }
-                    result = sendUpdateGroupMessage(groupInfoV2,
-                            groupGroupChangePair.first(),
-                            groupGroupChangePair.second());
-                }
-
-                return new Pair<>(group.getGroupId(), result.second());
-            } else {
-                var gv1 = (GroupInfoV1) group;
-                updateGroupV1(gv1, name, members, avatarFile);
-                messageBuilder = getGroupUpdateMessageBuilder(gv1);
-                g = gv1;
-            }
-        }
+    void setRegistrationLockPin(Optional<String> pin) throws IOException, UnauthenticatedResponseException;
 
-        account.getGroupStore().updateGroup(g);
+    Profile getRecipientProfile(RecipientIdentifier.Single recipient) throws UnregisteredUserException;
 
-        final var result = sendMessage(messageBuilder, g.getMembersIncludingPendingWithout(account.getSelfAddress()));
-        return new Pair<>(g.getGroupId(), result.second());
-    }
+    List<Group> getGroups();
 
-    private void updateGroupV1(
-            final GroupInfoV1 g,
-            final String name,
-            final Collection<SignalServiceAddress> members,
-            final File avatarFile
-    ) throws IOException {
-        if (name != null) {
-            g.name = name;
-        }
+    SendGroupMessageResults quitGroup(
+            GroupId groupId, Set<RecipientIdentifier.Single> groupAdmins
+    ) throws GroupNotFoundException, IOException, NotAGroupMemberException, LastGroupAdminException;
 
-        if (members != null) {
-            final var newE164Members = new HashSet<String>();
-            for (var member : members) {
-                if (g.isMember(member) || !member.getNumber().isPresent()) {
-                    continue;
-                }
-                newE164Members.add(member.getNumber().get());
-            }
-
-            final var registeredUsers = getRegisteredUsers(newE164Members);
-            if (registeredUsers.size() != newE164Members.size()) {
-                // Some of the new members are not registered on Signal
-                newE164Members.removeAll(registeredUsers.keySet());
-                throw new IOException("Failed to add members "
-                        + String.join(", ", newE164Members)
-                        + " to group: Not registered on Signal");
-            }
-
-            g.addMembers(members);
-        }
+    void deleteGroup(GroupId groupId) throws IOException;
 
-        if (avatarFile != null) {
-            avatarStore.storeGroupAvatar(g.getGroupId(),
-                    outputStream -> IOUtils.copyFileToStream(avatarFile, outputStream));
-        }
-    }
+    Pair<GroupId, SendGroupMessageResults> createGroup(
+            String name, Set<RecipientIdentifier.Single> members, File avatarFile
+    ) throws IOException, AttachmentInvalidException;
 
-    public Pair<GroupId, List<SendMessageResult>> joinGroup(
-            GroupInviteLinkUrl inviteLinkUrl
-    ) throws IOException, GroupLinkNotActiveException {
-        return sendJoinGroupMessage(inviteLinkUrl);
-    }
+    SendGroupMessageResults updateGroup(
+            final GroupId groupId, final UpdateGroup updateGroup
+    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException, GroupSendingNotAllowedException;
 
-    private Pair<GroupId, List<SendMessageResult>> sendJoinGroupMessage(
+    Pair<GroupId, SendGroupMessageResults> joinGroup(
             GroupInviteLinkUrl inviteLinkUrl
-    ) throws IOException, GroupLinkNotActiveException {
-        final var groupJoinInfo = groupHelper.getDecryptedGroupJoinInfo(inviteLinkUrl.getGroupMasterKey(),
-                inviteLinkUrl.getPassword());
-        final var groupChange = groupHelper.joinGroup(inviteLinkUrl.getGroupMasterKey(),
-                inviteLinkUrl.getPassword(),
-                groupJoinInfo);
-        final var group = getOrMigrateGroup(inviteLinkUrl.getGroupMasterKey(),
-                groupJoinInfo.getRevision() + 1,
-                groupChange.toByteArray());
-
-        if (group.getGroup() == null) {
-            // Only requested member, can't send update to group members
-            return new Pair<>(group.getGroupId(), List.of());
-        }
-
-        final var result = sendUpdateGroupMessage(group, group.getGroup(), groupChange);
-
-        return new Pair<>(group.getGroupId(), result.second());
-    }
-
-    private static int currentTimeDays() {
-        return (int) TimeUnit.MILLISECONDS.toDays(System.currentTimeMillis());
-    }
-
-    private GroupsV2AuthorizationString getGroupAuthForToday(
-            final GroupSecretParams groupSecretParams
-    ) throws IOException {
-        final var today = currentTimeDays();
-        // Returns credentials for the next 7 days
-        final var credentials = groupsV2Api.getCredentials(today);
-        // TODO cache credentials until they expire
-        var authCredentialResponse = credentials.get(today);
-        try {
-            return groupsV2Api.getGroupsV2AuthorizationString(account.getUuid(),
-                    today,
-                    groupSecretParams,
-                    authCredentialResponse);
-        } catch (VerificationFailedException e) {
-            throw new IOException(e);
-        }
-    }
-
-    private Pair<Long, List<SendMessageResult>> sendUpdateGroupMessage(
-            GroupInfoV2 group, DecryptedGroup newDecryptedGroup, GroupChange groupChange
-    ) throws IOException {
-        group.setGroup(newDecryptedGroup);
-        final var messageBuilder = getGroupUpdateMessageBuilder(group, groupChange.toByteArray());
-        account.getGroupStore().updateGroup(group);
-        return sendMessage(messageBuilder, group.getMembersIncludingPendingWithout(account.getSelfAddress()));
-    }
-
-    Pair<Long, List<SendMessageResult>> sendGroupInfoMessage(
-            GroupIdV1 groupId, SignalServiceAddress recipient
-    ) throws IOException, NotAGroupMemberException, GroupNotFoundException, AttachmentInvalidException {
-        GroupInfoV1 g;
-        var group = getGroupForSending(groupId);
-        if (!(group instanceof GroupInfoV1)) {
-            throw new RuntimeException("Received an invalid group request for a v2 group!");
-        }
-        g = (GroupInfoV1) group;
-
-        if (!g.isMember(recipient)) {
-            throw new NotAGroupMemberException(groupId, g.name);
-        }
-
-        var messageBuilder = getGroupUpdateMessageBuilder(g);
-
-        // Send group message only to the recipient who requested it
-        return sendMessage(messageBuilder, List.of(recipient));
-    }
-
-    private SignalServiceDataMessage.Builder getGroupUpdateMessageBuilder(GroupInfoV1 g) throws AttachmentInvalidException {
-        var group = SignalServiceGroup.newBuilder(SignalServiceGroup.Type.UPDATE)
-                .withId(g.getGroupId().serialize())
-                .withName(g.name)
-                .withMembers(new ArrayList<>(g.getMembers()));
-
-        try {
-            final var attachment = createGroupAvatarAttachment(g.getGroupId());
-            if (attachment.isPresent()) {
-                group.withAvatar(attachment.get());
-            }
-        } catch (IOException e) {
-            throw new AttachmentInvalidException(g.getGroupId().toBase64(), e);
-        }
-
-        return SignalServiceDataMessage.newBuilder()
-                .asGroupMessage(group.build())
-                .withExpiration(g.getMessageExpirationTime());
-    }
-
-    private SignalServiceDataMessage.Builder getGroupUpdateMessageBuilder(GroupInfoV2 g, byte[] signedGroupChange) {
-        var group = SignalServiceGroupV2.newBuilder(g.getMasterKey())
-                .withRevision(g.getGroup().getRevision())
-                .withSignedGroupChange(signedGroupChange);
-        return SignalServiceDataMessage.newBuilder()
-                .asGroupMessage(group.build())
-                .withExpiration(g.getMessageExpirationTime());
-    }
-
-    Pair<Long, List<SendMessageResult>> sendGroupInfoRequest(
-            GroupIdV1 groupId, SignalServiceAddress recipient
-    ) throws IOException {
-        var group = SignalServiceGroup.newBuilder(SignalServiceGroup.Type.REQUEST_INFO).withId(groupId.serialize());
+    ) throws IOException, GroupLinkNotActiveException;
 
-        var messageBuilder = SignalServiceDataMessage.newBuilder().asGroupMessage(group.build());
+    void sendTypingMessage(
+            TypingAction action, Set<RecipientIdentifier> recipients
+    ) throws IOException, UntrustedIdentityException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException;
 
-        // Send group info request message to the recipient who sent us a message with this groupId
-        return sendMessage(messageBuilder, List.of(recipient));
-    }
+    void sendReadReceipt(
+            RecipientIdentifier.Single sender, List<Long> messageIds
+    ) throws IOException, UntrustedIdentityException;
 
-    void sendReceipt(
-            SignalServiceAddress remoteAddress, long messageId
-    ) throws IOException, UntrustedIdentityException {
-        var receiptMessage = new SignalServiceReceiptMessage(SignalServiceReceiptMessage.Type.DELIVERY,
-                List.of(messageId),
-                System.currentTimeMillis());
+    void sendViewedReceipt(
+            RecipientIdentifier.Single sender, List<Long> messageIds
+    ) throws IOException, UntrustedIdentityException;
 
-        createMessageSender().sendReceipt(remoteAddress,
-                unidentifiedAccessHelper.getAccessFor(remoteAddress),
-                receiptMessage);
-    }
+    SendMessageResults sendMessage(
+            Message message, Set<RecipientIdentifier> recipients
+    ) throws IOException, AttachmentInvalidException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException;
 
-    public Pair<Long, List<SendMessageResult>> sendMessage(
-            String messageText, List<String> attachments, List<String> recipients
-    ) throws IOException, AttachmentInvalidException, InvalidNumberException {
-        final var messageBuilder = SignalServiceDataMessage.newBuilder().withBody(messageText);
-        if (attachments != null) {
-            var attachmentStreams = AttachmentUtils.getSignalServiceAttachments(attachments);
-
-            // Upload attachments here, so we only upload once even for multiple recipients
-            var messageSender = createMessageSender();
-            var attachmentPointers = new ArrayList<SignalServiceAttachment>(attachmentStreams.size());
-            for (var attachment : attachmentStreams) {
-                if (attachment.isStream()) {
-                    attachmentPointers.add(messageSender.uploadAttachment(attachment.asStream()));
-                } else if (attachment.isPointer()) {
-                    attachmentPointers.add(attachment.asPointer());
-                }
-            }
-
-            messageBuilder.withAttachments(attachmentPointers);
-        }
-        return sendMessage(messageBuilder, getSignalServiceAddresses(recipients));
-    }
+    SendMessageResults sendRemoteDeleteMessage(
+            long targetSentTimestamp, Set<RecipientIdentifier> recipients
+    ) throws IOException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException;
 
-    public Pair<Long, SendMessageResult> sendSelfMessage(
-            String messageText, List<String> attachments
-    ) throws IOException, AttachmentInvalidException {
-        final var messageBuilder = SignalServiceDataMessage.newBuilder().withBody(messageText);
-        if (attachments != null) {
-            messageBuilder.withAttachments(AttachmentUtils.getSignalServiceAttachments(attachments));
-        }
-        return sendSelfMessage(messageBuilder);
-    }
+    SendMessageResults sendMessageReaction(
+            String emoji,
+            boolean remove,
+            RecipientIdentifier.Single targetAuthor,
+            long targetSentTimestamp,
+            Set<RecipientIdentifier> recipients
+    ) throws IOException, NotAGroupMemberException, GroupNotFoundException, GroupSendingNotAllowedException;
 
-    public Pair<Long, List<SendMessageResult>> sendRemoteDeleteMessage(
-            long targetSentTimestamp, List<String> recipients
-    ) throws IOException, InvalidNumberException {
-        var delete = new SignalServiceDataMessage.RemoteDelete(targetSentTimestamp);
-        final var messageBuilder = SignalServiceDataMessage.newBuilder().withRemoteDelete(delete);
-        return sendMessage(messageBuilder, getSignalServiceAddresses(recipients));
-    }
+    SendMessageResults sendEndSessionMessage(Set<RecipientIdentifier.Single> recipients) throws IOException;
 
-    public Pair<Long, List<SendMessageResult>> sendGroupRemoteDeleteMessage(
-            long targetSentTimestamp, GroupId groupId
-    ) throws IOException, NotAGroupMemberException, GroupNotFoundException {
-        var delete = new SignalServiceDataMessage.RemoteDelete(targetSentTimestamp);
-        final var messageBuilder = SignalServiceDataMessage.newBuilder().withRemoteDelete(delete);
-        return sendGroupMessage(messageBuilder, groupId);
-    }
+    void setContactName(
+            RecipientIdentifier.Single recipient, String name
+    ) throws NotMasterDeviceException, UnregisteredUserException;
 
-    public Pair<Long, List<SendMessageResult>> sendMessageReaction(
-            String emoji, boolean remove, String targetAuthor, long targetSentTimestamp, List<String> recipients
-    ) throws IOException, InvalidNumberException {
-        var reaction = new SignalServiceDataMessage.Reaction(emoji,
-                remove,
-                canonicalizeAndResolveSignalServiceAddress(targetAuthor),
-                targetSentTimestamp);
-        final var messageBuilder = SignalServiceDataMessage.newBuilder().withReaction(reaction);
-        return sendMessage(messageBuilder, getSignalServiceAddresses(recipients));
-    }
+    void setContactBlocked(
+            RecipientIdentifier.Single recipient, boolean blocked
+    ) throws NotMasterDeviceException, IOException;
 
-    public Pair<Long, List<SendMessageResult>> sendEndSessionMessage(List<String> recipients) throws IOException, InvalidNumberException {
-        var messageBuilder = SignalServiceDataMessage.newBuilder().asEndSessionMessage();
-
-        final var signalServiceAddresses = getSignalServiceAddresses(recipients);
-        try {
-            return sendMessage(messageBuilder, signalServiceAddresses);
-        } catch (Exception e) {
-            for (var address : signalServiceAddresses) {
-                handleEndSession(address);
-            }
-            account.save();
-            throw e;
-        }
-    }
+    void setGroupBlocked(
+            GroupId groupId, boolean blocked
+    ) throws GroupNotFoundException, IOException, NotMasterDeviceException;
 
-    public String getContactName(String number) throws InvalidNumberException {
-        var contact = account.getContactStore().getContact(canonicalizeAndResolveSignalServiceAddress(number));
-        if (contact == null) {
-            return "";
-        } else {
-            return contact.name;
-        }
-    }
-
-    public void setContactName(String number, String name) throws InvalidNumberException {
-        final var address = canonicalizeAndResolveSignalServiceAddress(number);
-        var contact = account.getContactStore().getContact(address);
-        if (contact == null) {
-            contact = new ContactInfo(address);
-        }
-        contact.name = name;
-        account.getContactStore().updateContact(contact);
-        account.save();
-    }
+    void setExpirationTimer(
+            RecipientIdentifier.Single recipient, int messageExpirationTimer
+    ) throws IOException;
 
-    public void setContactBlocked(String number, boolean blocked) throws InvalidNumberException {
-        setContactBlocked(canonicalizeAndResolveSignalServiceAddress(number), blocked);
-    }
+    URI uploadStickerPack(File path) throws IOException, StickerPackInvalidException;
 
-    private void setContactBlocked(SignalServiceAddress address, boolean blocked) {
-        var contact = account.getContactStore().getContact(address);
-        if (contact == null) {
-            contact = new ContactInfo(address);
-        }
-        contact.blocked = blocked;
-        account.getContactStore().updateContact(contact);
-        account.save();
-    }
-
-    public void setGroupBlocked(final GroupId groupId, final boolean blocked) throws GroupNotFoundException {
-        var group = getGroup(groupId);
-        if (group == null) {
-            throw new GroupNotFoundException(groupId);
-        }
-
-        group.setBlocked(blocked);
-        account.getGroupStore().updateGroup(group);
-        account.save();
-    }
+    void requestAllSyncData() throws IOException;
 
     /**
-     * Change the expiration timer for a contact
+     * Receive new messages from server, returns if no new message arrive in a timespan of timeout.
      */
-    public void setExpirationTimer(SignalServiceAddress address, int messageExpirationTimer) throws IOException {
-        var contact = account.getContactStore().getContact(address);
-        contact.messageExpirationTime = messageExpirationTimer;
-        account.getContactStore().updateContact(contact);
-        sendExpirationTimerUpdate(address);
-        account.save();
-    }
-
-    private void sendExpirationTimerUpdate(SignalServiceAddress address) throws IOException {
-        final var messageBuilder = SignalServiceDataMessage.newBuilder().asExpirationUpdate();
-        sendMessage(messageBuilder, List.of(address));
-    }
+    void receiveMessages(long timeout, TimeUnit unit, ReceiveMessageHandler handler) throws IOException;
 
     /**
-     * Change the expiration timer for a contact
+     * Receive new messages from server, returns only if the thread is interrupted.
      */
-    public void setExpirationTimer(
-            String number, int messageExpirationTimer
-    ) throws IOException, InvalidNumberException {
-        var address = canonicalizeAndResolveSignalServiceAddress(number);
-        setExpirationTimer(address, messageExpirationTimer);
-    }
+    void receiveMessages(ReceiveMessageHandler handler) throws IOException;
 
-    /**
-     * Change the expiration timer for a group
-     */
-    public void setExpirationTimer(GroupId groupId, int messageExpirationTimer) {
-        var g = getGroup(groupId);
-        if (g instanceof GroupInfoV1) {
-            var groupInfoV1 = (GroupInfoV1) g;
-            groupInfoV1.messageExpirationTime = messageExpirationTimer;
-            account.getGroupStore().updateGroup(groupInfoV1);
-        } else {
-            throw new RuntimeException("TODO Not implemented!");
-        }
-    }
+    void setIgnoreAttachments(boolean ignoreAttachments);
 
-    /**
-     * Upload the sticker pack from path.
-     *
-     * @param path Path can be a path to a manifest.json file or to a zip file that contains a manifest.json file
-     * @return if successful, returns the URL to install the sticker pack in the signal app
-     */
-    public String uploadStickerPack(File path) throws IOException, StickerPackInvalidException {
-        var manifest = StickerUtils.getSignalServiceStickerManifestUpload(path);
-
-        var messageSender = createMessageSender();
-
-        var packKey = KeyUtils.createStickerUploadKey();
-        var packId = messageSender.uploadStickerManifest(manifest, packKey);
-
-        var sticker = new Sticker(Hex.fromStringCondensed(packId), packKey);
-        account.getStickerStore().updateSticker(sticker);
-        account.save();
-
-        try {
-            return new URI("https",
-                    "signal.art",
-                    "/addstickers/",
-                    "pack_id=" + URLEncoder.encode(packId, StandardCharsets.UTF_8) + "&pack_key=" + URLEncoder.encode(
-                            Hex.toStringCondensed(packKey),
-                            StandardCharsets.UTF_8)).toString();
-        } catch (URISyntaxException e) {
-            throw new AssertionError(e);
-        }
-    }
+    boolean hasCaughtUpWithOldMessages();
 
-    void requestSyncGroups() throws IOException {
-        var r = SignalServiceProtos.SyncMessage.Request.newBuilder()
-                .setType(SignalServiceProtos.SyncMessage.Request.Type.GROUPS)
-                .build();
-        var message = SignalServiceSyncMessage.forRequest(new RequestMessage(r));
-        try {
-            sendSyncMessage(message);
-        } catch (UntrustedIdentityException e) {
-            throw new AssertionError(e);
-        }
-    }
+    boolean isContactBlocked(RecipientIdentifier.Single recipient);
 
-    void requestSyncContacts() throws IOException {
-        var r = SignalServiceProtos.SyncMessage.Request.newBuilder()
-                .setType(SignalServiceProtos.SyncMessage.Request.Type.CONTACTS)
-                .build();
-        var message = SignalServiceSyncMessage.forRequest(new RequestMessage(r));
-        try {
-            sendSyncMessage(message);
-        } catch (UntrustedIdentityException e) {
-            throw new AssertionError(e);
-        }
-    }
+    File getAttachmentFile(SignalServiceAttachmentRemoteId attachmentId);
 
-    void requestSyncBlocked() throws IOException {
-        var r = SignalServiceProtos.SyncMessage.Request.newBuilder()
-                .setType(SignalServiceProtos.SyncMessage.Request.Type.BLOCKED)
-                .build();
-        var message = SignalServiceSyncMessage.forRequest(new RequestMessage(r));
-        try {
-            sendSyncMessage(message);
-        } catch (UntrustedIdentityException e) {
-            throw new AssertionError(e);
-        }
-    }
+    void sendContacts() throws IOException;
 
-    void requestSyncConfiguration() throws IOException {
-        var r = SignalServiceProtos.SyncMessage.Request.newBuilder()
-                .setType(SignalServiceProtos.SyncMessage.Request.Type.CONFIGURATION)
-                .build();
-        var message = SignalServiceSyncMessage.forRequest(new RequestMessage(r));
-        try {
-            sendSyncMessage(message);
-        } catch (UntrustedIdentityException e) {
-            throw new AssertionError(e);
-        }
-    }
+    List<Pair<RecipientAddress, Contact>> getContacts();
 
-    void requestSyncKeys() throws IOException {
-        var r = SignalServiceProtos.SyncMessage.Request.newBuilder()
-                .setType(SignalServiceProtos.SyncMessage.Request.Type.KEYS)
-                .build();
-        var message = SignalServiceSyncMessage.forRequest(new RequestMessage(r));
-        try {
-            sendSyncMessage(message);
-        } catch (UntrustedIdentityException e) {
-            throw new AssertionError(e);
-        }
-    }
+    String getContactOrProfileName(RecipientIdentifier.Single recipient);
 
-    private byte[] getSenderCertificate() {
-        // TODO support UUID capable sender certificates
-        // byte[] certificate = accountManager.getSenderCertificateForPhoneNumberPrivacy();
-        byte[] certificate;
-        try {
-            certificate = accountManager.getSenderCertificate();
-        } catch (IOException e) {
-            logger.warn("Failed to get sender certificate, ignoring: {}", e.getMessage());
-            return null;
-        }
-        // TODO cache for a day
-        return certificate;
-    }
-
-    private void sendSyncMessage(SignalServiceSyncMessage message) throws IOException, UntrustedIdentityException {
-        var messageSender = createMessageSender();
-        messageSender.sendMessage(message, unidentifiedAccessHelper.getAccessForSync());
-    }
-
-    private Collection<SignalServiceAddress> getSignalServiceAddresses(Collection<String> numbers) throws InvalidNumberException {
-        final var signalServiceAddresses = new HashSet<SignalServiceAddress>(numbers.size());
-        final var addressesMissingUuid = new HashSet<SignalServiceAddress>();
-
-        for (var number : numbers) {
-            final var resolvedAddress = canonicalizeAndResolveSignalServiceAddress(number);
-            if (resolvedAddress.getUuid().isPresent()) {
-                signalServiceAddresses.add(resolvedAddress);
-            } else {
-                addressesMissingUuid.add(resolvedAddress);
-            }
-        }
-
-        final var numbersMissingUuid = addressesMissingUuid.stream()
-                .map(a -> a.getNumber().get())
-                .collect(Collectors.toSet());
-        Map<String, UUID> registeredUsers;
-        try {
-            registeredUsers = getRegisteredUsers(numbersMissingUuid);
-        } catch (IOException e) {
-            logger.warn("Failed to resolve uuids from server, ignoring: {}", e.getMessage());
-            registeredUsers = Map.of();
-        }
-
-        for (var address : addressesMissingUuid) {
-            final var number = address.getNumber().get();
-            if (registeredUsers.containsKey(number)) {
-                final var newAddress = resolveSignalServiceAddress(new SignalServiceAddress(registeredUsers.get(number),
-                        number));
-                signalServiceAddresses.add(newAddress);
-            } else {
-                signalServiceAddresses.add(address);
-            }
-        }
-
-        return signalServiceAddresses;
-    }
-
-    private Map<String, UUID> getRegisteredUsers(final Set<String> numbersMissingUuid) throws IOException {
-        try {
-            return accountManager.getRegisteredUsers(ServiceConfig.getIasKeyStore(),
-                    numbersMissingUuid,
-                    serviceEnvironmentConfig.getCdsMrenclave());
-        } catch (Quote.InvalidQuoteFormatException | UnauthenticatedQuoteException | SignatureException | UnauthenticatedResponseException | InvalidKeyException e) {
-            throw new IOException(e);
-        }
-    }
-
-    private Pair<Long, List<SendMessageResult>> sendMessage(
-            SignalServiceDataMessage.Builder messageBuilder, Collection<SignalServiceAddress> recipients
-    ) throws IOException {
-        recipients = recipients.stream().map(this::resolveSignalServiceAddress).collect(Collectors.toSet());
-        final var timestamp = System.currentTimeMillis();
-        messageBuilder.withTimestamp(timestamp);
-        getOrCreateMessagePipe();
-        getOrCreateUnidentifiedMessagePipe();
-        SignalServiceDataMessage message = null;
-        try {
-            message = messageBuilder.build();
-            if (message.getGroupContext().isPresent()) {
-                try {
-                    var messageSender = createMessageSender();
-                    final var isRecipientUpdate = false;
-                    var result = messageSender.sendMessage(new ArrayList<>(recipients),
-                            unidentifiedAccessHelper.getAccessFor(recipients),
-                            isRecipientUpdate,
-                            message);
-                    return new Pair<>(timestamp, result);
-                } catch (UntrustedIdentityException e) {
-                    return new Pair<>(timestamp, List.of());
-                }
-            } else {
-                // Send to all individually, so sync messages are sent correctly
-                messageBuilder.withProfileKey(account.getProfileKey().serialize());
-                var results = new ArrayList<SendMessageResult>(recipients.size());
-                for (var address : recipients) {
-                    final var contact = account.getContactStore().getContact(address);
-                    final var expirationTime = contact != null ? contact.messageExpirationTime : 0;
-                    messageBuilder.withExpiration(expirationTime);
-                    message = messageBuilder.build();
-                    results.add(sendMessage(address, message));
-                }
-                return new Pair<>(timestamp, results);
-            }
-        } finally {
-            if (message != null && message.isEndSession()) {
-                for (var recipient : recipients) {
-                    handleEndSession(recipient);
-                }
-            }
-            account.save();
-        }
-    }
-
-    private Pair<Long, SendMessageResult> sendSelfMessage(
-            SignalServiceDataMessage.Builder messageBuilder
-    ) throws IOException {
-        final var timestamp = System.currentTimeMillis();
-        messageBuilder.withTimestamp(timestamp);
-        getOrCreateMessagePipe();
-        getOrCreateUnidentifiedMessagePipe();
-        try {
-            final var address = getSelfAddress();
-
-            final var contact = account.getContactStore().getContact(address);
-            final var expirationTime = contact != null ? contact.messageExpirationTime : 0;
-            messageBuilder.withExpiration(expirationTime);
-
-            var message = messageBuilder.build();
-            final var result = sendSelfMessage(message);
-            return new Pair<>(timestamp, result);
-        } finally {
-            account.save();
-        }
-    }
-
-    private SendMessageResult sendSelfMessage(SignalServiceDataMessage message) throws IOException {
-        var messageSender = createMessageSender();
-
-        var recipient = account.getSelfAddress();
-
-        final var unidentifiedAccess = unidentifiedAccessHelper.getAccessFor(recipient);
-        var transcript = new SentTranscriptMessage(Optional.of(recipient),
-                message.getTimestamp(),
-                message,
-                message.getExpiresInSeconds(),
-                Map.of(recipient, unidentifiedAccess.isPresent()),
-                false);
-        var syncMessage = SignalServiceSyncMessage.forSentTranscript(transcript);
-
-        try {
-            var startTime = System.currentTimeMillis();
-            messageSender.sendMessage(syncMessage, unidentifiedAccess);
-            return SendMessageResult.success(recipient,
-                    unidentifiedAccess.isPresent(),
-                    false,
-                    System.currentTimeMillis() - startTime);
-        } catch (UntrustedIdentityException e) {
-            return SendMessageResult.identityFailure(recipient, e.getIdentityKey());
-        }
-    }
-
-    private SendMessageResult sendMessage(
-            SignalServiceAddress address, SignalServiceDataMessage message
-    ) throws IOException {
-        var messageSender = createMessageSender();
-
-        try {
-            return messageSender.sendMessage(address, unidentifiedAccessHelper.getAccessFor(address), message);
-        } catch (UntrustedIdentityException e) {
-            return SendMessageResult.identityFailure(address, e.getIdentityKey());
-        }
-    }
-
-    private SignalServiceContent decryptMessage(SignalServiceEnvelope envelope) throws InvalidMetadataMessageException, ProtocolInvalidMessageException, ProtocolDuplicateMessageException, ProtocolLegacyMessageException, ProtocolInvalidKeyIdException, InvalidMetadataVersionException, ProtocolInvalidVersionException, ProtocolNoSessionException, ProtocolInvalidKeyException, SelfSendException, UnsupportedDataMessageException, org.whispersystems.libsignal.UntrustedIdentityException {
-        var cipher = new SignalServiceCipher(account.getSelfAddress(),
-                account.getSignalProtocolStore(),
-                certificateValidator);
-        try {
-            return cipher.decrypt(envelope);
-        } catch (ProtocolUntrustedIdentityException e) {
-            if (e.getCause() instanceof org.whispersystems.libsignal.UntrustedIdentityException) {
-                throw (org.whispersystems.libsignal.UntrustedIdentityException) e.getCause();
-            }
-            throw new AssertionError(e);
-        }
-    }
-
-    private void handleEndSession(SignalServiceAddress source) {
-        account.getSessionStore().deleteAllSessions(source.getIdentifier());
-    }
-
-    private List<HandleAction> handleSignalServiceDataMessage(
-            SignalServiceDataMessage message,
-            boolean isSync,
-            SignalServiceAddress source,
-            SignalServiceAddress destination,
-            boolean ignoreAttachments
-    ) {
-        var actions = new ArrayList<HandleAction>();
-        if (message.getGroupContext().isPresent()) {
-            if (message.getGroupContext().get().getGroupV1().isPresent()) {
-                var groupInfo = message.getGroupContext().get().getGroupV1().get();
-                var groupId = GroupId.v1(groupInfo.getGroupId());
-                var group = getGroup(groupId);
-                if (group == null || group instanceof GroupInfoV1) {
-                    var groupV1 = (GroupInfoV1) group;
-                    switch (groupInfo.getType()) {
-                        case UPDATE: {
-                            if (groupV1 == null) {
-                                groupV1 = new GroupInfoV1(groupId);
-                            }
-
-                            if (groupInfo.getAvatar().isPresent()) {
-                                var avatar = groupInfo.getAvatar().get();
-                                downloadGroupAvatar(avatar, groupV1.getGroupId());
-                            }
-
-                            if (groupInfo.getName().isPresent()) {
-                                groupV1.name = groupInfo.getName().get();
-                            }
-
-                            if (groupInfo.getMembers().isPresent()) {
-                                groupV1.addMembers(groupInfo.getMembers()
-                                        .get()
-                                        .stream()
-                                        .map(this::resolveSignalServiceAddress)
-                                        .collect(Collectors.toSet()));
-                            }
-
-                            account.getGroupStore().updateGroup(groupV1);
-                            break;
-                        }
-                        case DELIVER:
-                            if (groupV1 == null && !isSync) {
-                                actions.add(new SendGroupInfoRequestAction(source, groupId));
-                            }
-                            break;
-                        case QUIT: {
-                            if (groupV1 != null) {
-                                groupV1.removeMember(source);
-                                account.getGroupStore().updateGroup(groupV1);
-                            }
-                            break;
-                        }
-                        case REQUEST_INFO:
-                            if (groupV1 != null && !isSync) {
-                                actions.add(new SendGroupInfoAction(source, groupV1.getGroupId()));
-                            }
-                            break;
-                    }
-                } else {
-                    // Received a group v1 message for a v2 group
-                }
-            }
-            if (message.getGroupContext().get().getGroupV2().isPresent()) {
-                final var groupContext = message.getGroupContext().get().getGroupV2().get();
-                final var groupMasterKey = groupContext.getMasterKey();
-
-                getOrMigrateGroup(groupMasterKey,
-                        groupContext.getRevision(),
-                        groupContext.hasSignedGroupChange() ? groupContext.getSignedGroupChange() : null);
-            }
-        }
-
-        final var conversationPartnerAddress = isSync ? destination : source;
-        if (conversationPartnerAddress != null && message.isEndSession()) {
-            handleEndSession(conversationPartnerAddress);
-        }
-        if (message.isExpirationUpdate() || message.getBody().isPresent()) {
-            if (message.getGroupContext().isPresent()) {
-                if (message.getGroupContext().get().getGroupV1().isPresent()) {
-                    var groupInfo = message.getGroupContext().get().getGroupV1().get();
-                    var group = account.getGroupStore().getOrCreateGroupV1(GroupId.v1(groupInfo.getGroupId()));
-                    if (group != null) {
-                        if (group.messageExpirationTime != message.getExpiresInSeconds()) {
-                            group.messageExpirationTime = message.getExpiresInSeconds();
-                            account.getGroupStore().updateGroup(group);
-                        }
-                    }
-                } else if (message.getGroupContext().get().getGroupV2().isPresent()) {
-                    // disappearing message timer already stored in the DecryptedGroup
-                }
-            } else if (conversationPartnerAddress != null) {
-                var contact = account.getContactStore().getContact(conversationPartnerAddress);
-                if (contact == null) {
-                    contact = new ContactInfo(conversationPartnerAddress);
-                }
-                if (contact.messageExpirationTime != message.getExpiresInSeconds()) {
-                    contact.messageExpirationTime = message.getExpiresInSeconds();
-                    account.getContactStore().updateContact(contact);
-                }
-            }
-        }
-        if (!ignoreAttachments) {
-            if (message.getAttachments().isPresent()) {
-                for (var attachment : message.getAttachments().get()) {
-                    downloadAttachment(attachment);
-                }
-            }
-            if (message.getSharedContacts().isPresent()) {
-                for (var contact : message.getSharedContacts().get()) {
-                    if (contact.getAvatar().isPresent()) {
-                        downloadAttachment(contact.getAvatar().get().getAttachment());
-                    }
-                }
-            }
-        }
-        if (message.getProfileKey().isPresent() && message.getProfileKey().get().length == 32) {
-            final ProfileKey profileKey;
-            try {
-                profileKey = new ProfileKey(message.getProfileKey().get());
-            } catch (InvalidInputException e) {
-                throw new AssertionError(e);
-            }
-            if (source.matches(account.getSelfAddress())) {
-                this.account.setProfileKey(profileKey);
-            }
-            this.account.getProfileStore().storeProfileKey(source, profileKey);
-        }
-        if (message.getPreviews().isPresent()) {
-            final var previews = message.getPreviews().get();
-            for (var preview : previews) {
-                if (preview.getImage().isPresent()) {
-                    downloadAttachment(preview.getImage().get());
-                }
-            }
-        }
-        if (message.getQuote().isPresent()) {
-            final var quote = message.getQuote().get();
-
-            for (var quotedAttachment : quote.getAttachments()) {
-                final var thumbnail = quotedAttachment.getThumbnail();
-                if (thumbnail != null) {
-                    downloadAttachment(thumbnail);
-                }
-            }
-        }
-        if (message.getSticker().isPresent()) {
-            final var messageSticker = message.getSticker().get();
-            var sticker = account.getStickerStore().getSticker(messageSticker.getPackId());
-            if (sticker == null) {
-                sticker = new Sticker(messageSticker.getPackId(), messageSticker.getPackKey());
-                account.getStickerStore().updateSticker(sticker);
-            }
-        }
-        return actions;
-    }
-
-    private GroupInfoV2 getOrMigrateGroup(
-            final GroupMasterKey groupMasterKey, final int revision, final byte[] signedGroupChange
-    ) {
-        final var groupSecretParams = GroupSecretParams.deriveFromMasterKey(groupMasterKey);
-
-        var groupId = GroupUtils.getGroupIdV2(groupSecretParams);
-        var groupInfo = getGroup(groupId);
-        final GroupInfoV2 groupInfoV2;
-        if (groupInfo instanceof GroupInfoV1) {
-            // Received a v2 group message for a v1 group, we need to locally migrate the group
-            account.getGroupStore().deleteGroup(groupInfo.getGroupId());
-            groupInfoV2 = new GroupInfoV2(groupId, groupMasterKey);
-            logger.info("Locally migrated group {} to group v2, id: {}",
-                    groupInfo.getGroupId().toBase64(),
-                    groupInfoV2.getGroupId().toBase64());
-        } else if (groupInfo instanceof GroupInfoV2) {
-            groupInfoV2 = (GroupInfoV2) groupInfo;
-        } else {
-            groupInfoV2 = new GroupInfoV2(groupId, groupMasterKey);
-        }
-
-        if (groupInfoV2.getGroup() == null || groupInfoV2.getGroup().getRevision() < revision) {
-            DecryptedGroup group = null;
-            if (signedGroupChange != null
-                    && groupInfoV2.getGroup() != null
-                    && groupInfoV2.getGroup().getRevision() + 1 == revision) {
-                group = groupHelper.getUpdatedDecryptedGroup(groupInfoV2.getGroup(), signedGroupChange, groupMasterKey);
-            }
-            if (group == null) {
-                group = groupHelper.getDecryptedGroup(groupSecretParams);
-            }
-            if (group != null) {
-                storeProfileKeysFromMembers(group);
-                final var avatar = group.getAvatar();
-                if (avatar != null && !avatar.isEmpty()) {
-                    downloadGroupAvatar(groupId, groupSecretParams, avatar);
-                }
-            }
-            groupInfoV2.setGroup(group);
-            account.getGroupStore().updateGroup(groupInfoV2);
-        }
-
-        return groupInfoV2;
-    }
-
-    private void storeProfileKeysFromMembers(final DecryptedGroup group) {
-        for (var member : group.getMembersList()) {
-            final var address = resolveSignalServiceAddress(new SignalServiceAddress(UuidUtil.parseOrThrow(member.getUuid()
-                    .toByteArray()), null));
-            try {
-                account.getProfileStore()
-                        .storeProfileKey(address, new ProfileKey(member.getProfileKey().toByteArray()));
-            } catch (InvalidInputException ignored) {
-            }
-        }
-    }
-
-    private void retryFailedReceivedMessages(ReceiveMessageHandler handler, boolean ignoreAttachments) {
-        for (var cachedMessage : account.getMessageCache().getCachedMessages()) {
-            retryFailedReceivedMessage(handler, ignoreAttachments, cachedMessage);
-        }
-    }
-
-    private void retryFailedReceivedMessage(
-            final ReceiveMessageHandler handler, final boolean ignoreAttachments, final CachedMessage cachedMessage
-    ) {
-        var envelope = cachedMessage.loadEnvelope();
-        if (envelope == null) {
-            return;
-        }
-        SignalServiceContent content = null;
-        if (!envelope.isReceipt()) {
-            try {
-                content = decryptMessage(envelope);
-            } catch (org.whispersystems.libsignal.UntrustedIdentityException e) {
-                if (!envelope.hasSource()) {
-                    final var recipientId = resolveRecipient(((org.whispersystems.libsignal.UntrustedIdentityException) e)
-                            .getName());
-                    try {
-                        account.getMessageCache().replaceSender(cachedMessage, recipientId);
-                    } catch (IOException ioException) {
-                        logger.warn("Failed to move cached message to recipient folder: {}", ioException.getMessage());
-                    }
-                }
-                return;
-            } catch (Exception er) {
-                // All other errors are not recoverable, so delete the cached message
-                cachedMessage.delete();
-                return;
-            }
-            var actions = handleMessage(envelope, content, ignoreAttachments);
-            for (var action : actions) {
-                try {
-                    action.execute(this);
-                } catch (Throwable e) {
-                    logger.warn("Message action failed.", e);
-                }
-            }
-        }
-        account.save();
-        handler.handleMessage(envelope, content, null);
-        cachedMessage.delete();
-    }
-
-    public void receiveMessages(
-            long timeout,
-            TimeUnit unit,
-            boolean returnOnTimeout,
-            boolean ignoreAttachments,
-            ReceiveMessageHandler handler
-    ) throws IOException {
-        retryFailedReceivedMessages(handler, ignoreAttachments);
-
-        Set<HandleAction> queuedActions = null;
-
-        final var messagePipe = getOrCreateMessagePipe();
-
-        var hasCaughtUpWithOldMessages = false;
-
-        while (true) {
-            SignalServiceEnvelope envelope;
-            SignalServiceContent content = null;
-            Exception exception = null;
-            final CachedMessage[] cachedMessage = {null};
-            try {
-                var result = messagePipe.readOrEmpty(timeout, unit, envelope1 -> {
-                    final var recipientId = envelope1.hasSource()
-                            ? resolveRecipient(envelope1.getSourceIdentifier())
-                            : null;
-                    // store message on disk, before acknowledging receipt to the server
-                    cachedMessage[0] = account.getMessageCache().cacheMessage(envelope1, recipientId);
-                });
-                if (result.isPresent()) {
-                    envelope = result.get();
-                } else {
-                    // Received indicator that server queue is empty
-                    hasCaughtUpWithOldMessages = true;
-
-                    if (queuedActions != null) {
-                        for (var action : queuedActions) {
-                            try {
-                                action.execute(this);
-                            } catch (Throwable e) {
-                                logger.warn("Message action failed.", e);
-                            }
-                        }
-                        account.save();
-                        queuedActions.clear();
-                        queuedActions = null;
-                    }
-
-                    // Continue to wait another timeout for new messages
-                    continue;
-                }
-            } catch (TimeoutException e) {
-                if (returnOnTimeout) return;
-                continue;
-            }
-
-            if (envelope.hasSource()) {
-                // Store uuid if we don't have it already
-                resolveRecipientTrusted(envelope.getSourceAddress());
-            }
-            if (!envelope.isReceipt()) {
-                try {
-                    content = decryptMessage(envelope);
-                } catch (Exception e) {
-                    exception = e;
-                }
-                var actions = handleMessage(envelope, content, ignoreAttachments);
-                if (hasCaughtUpWithOldMessages) {
-                    for (var action : actions) {
-                        try {
-                            action.execute(this);
-                        } catch (Throwable e) {
-                            logger.warn("Message action failed.", e);
-                        }
-                    }
-                } else {
-                    if (queuedActions == null) {
-                        queuedActions = new HashSet<>();
-                    }
-                    queuedActions.addAll(actions);
-                }
-            }
-            account.save();
-            if (isMessageBlocked(envelope, content)) {
-                logger.info("Ignoring a message from blocked user/group: {}", envelope.getTimestamp());
-            } else if (isNotAGroupMember(envelope, content)) {
-                logger.info("Ignoring a message from a non group member: {}", envelope.getTimestamp());
-            } else {
-                handler.handleMessage(envelope, content, exception);
-            }
-            if (cachedMessage[0] != null) {
-                if (exception instanceof org.whispersystems.libsignal.UntrustedIdentityException) {
-                    if (!envelope.hasSource()) {
-                        final var recipientId = resolveRecipient(((org.whispersystems.libsignal.UntrustedIdentityException) exception)
-                                .getName());
-                        try {
-                            cachedMessage[0] = account.getMessageCache().replaceSender(cachedMessage[0], recipientId);
-                        } catch (IOException ioException) {
-                            logger.warn("Failed to move cached message to recipient folder: {}",
-                                    ioException.getMessage());
-                        }
-                    }
-                } else {
-                    cachedMessage[0].delete();
-                }
-            }
-        }
-    }
-
-    private boolean isMessageBlocked(
-            SignalServiceEnvelope envelope, SignalServiceContent content
-    ) {
-        SignalServiceAddress source;
-        if (!envelope.isUnidentifiedSender() && envelope.hasSource()) {
-            source = envelope.getSourceAddress();
-        } else if (content != null) {
-            source = content.getSender();
-        } else {
-            return false;
-        }
-        var sourceContact = account.getContactStore().getContact(source);
-        if (sourceContact != null && sourceContact.blocked) {
-            return true;
-        }
-
-        if (content != null && content.getDataMessage().isPresent()) {
-            var message = content.getDataMessage().get();
-            if (message.getGroupContext().isPresent()) {
-                var groupId = GroupUtils.getGroupId(message.getGroupContext().get());
-                var group = getGroup(groupId);
-                if (group != null && group.isBlocked()) {
-                    return true;
-                }
-            }
-        }
-        return false;
-    }
-
-    private boolean isNotAGroupMember(
-            SignalServiceEnvelope envelope, SignalServiceContent content
-    ) {
-        SignalServiceAddress source;
-        if (!envelope.isUnidentifiedSender() && envelope.hasSource()) {
-            source = envelope.getSourceAddress();
-        } else if (content != null) {
-            source = content.getSender();
-        } else {
-            return false;
-        }
+    Group getGroup(GroupId groupId);
 
-        if (content != null && content.getDataMessage().isPresent()) {
-            var message = content.getDataMessage().get();
-            if (message.getGroupContext().isPresent()) {
-                if (message.getGroupContext().get().getGroupV1().isPresent()) {
-                    var groupInfo = message.getGroupContext().get().getGroupV1().get();
-                    if (groupInfo.getType() == SignalServiceGroup.Type.QUIT) {
-                        return false;
-                    }
-                }
-                var groupId = GroupUtils.getGroupId(message.getGroupContext().get());
-                var group = getGroup(groupId);
-                if (group != null && !group.isMember(source)) {
-                    return true;
-                }
-            }
-        }
-        return false;
-    }
+    List<Identity> getIdentities();
 
-    private List<HandleAction> handleMessage(
-            SignalServiceEnvelope envelope, SignalServiceContent content, boolean ignoreAttachments
-    ) {
-        var actions = new ArrayList<HandleAction>();
-        if (content != null) {
-            final SignalServiceAddress sender;
-            if (!envelope.isUnidentifiedSender() && envelope.hasSource()) {
-                sender = envelope.getSourceAddress();
-            } else {
-                sender = content.getSender();
-            }
-            // Store uuid if we don't have it already
-            resolveSignalServiceAddress(sender);
-
-            if (content.getDataMessage().isPresent()) {
-                var message = content.getDataMessage().get();
-
-                if (content.isNeedsReceipt()) {
-                    actions.add(new SendReceiptAction(sender, message.getTimestamp()));
-                }
-
-                actions.addAll(handleSignalServiceDataMessage(message,
-                        false,
-                        sender,
-                        account.getSelfAddress(),
-                        ignoreAttachments));
-            }
-            if (content.getSyncMessage().isPresent()) {
-                account.setMultiDevice(true);
-                var syncMessage = content.getSyncMessage().get();
-                if (syncMessage.getSent().isPresent()) {
-                    var message = syncMessage.getSent().get();
-                    final var destination = message.getDestination().orNull();
-                    actions.addAll(handleSignalServiceDataMessage(message.getMessage(),
-                            true,
-                            sender,
-                            destination,
-                            ignoreAttachments));
-                }
-                if (syncMessage.getRequest().isPresent()) {
-                    var rm = syncMessage.getRequest().get();
-                    if (rm.isContactsRequest()) {
-                        actions.add(SendSyncContactsAction.create());
-                    }
-                    if (rm.isGroupsRequest()) {
-                        actions.add(SendSyncGroupsAction.create());
-                    }
-                    if (rm.isBlockedListRequest()) {
-                        actions.add(SendSyncBlockedListAction.create());
-                    }
-                    // TODO Handle rm.isConfigurationRequest(); rm.isKeysRequest();
-                }
-                if (syncMessage.getGroups().isPresent()) {
-                    File tmpFile = null;
-                    try {
-                        tmpFile = IOUtils.createTempFile();
-                        final var groupsMessage = syncMessage.getGroups().get();
-                        try (var attachmentAsStream = retrieveAttachmentAsStream(groupsMessage.asPointer(), tmpFile)) {
-                            var s = new DeviceGroupsInputStream(attachmentAsStream);
-                            DeviceGroup g;
-                            while ((g = s.read()) != null) {
-                                var syncGroup = account.getGroupStore().getOrCreateGroupV1(GroupId.v1(g.getId()));
-                                if (syncGroup != null) {
-                                    if (g.getName().isPresent()) {
-                                        syncGroup.name = g.getName().get();
-                                    }
-                                    syncGroup.addMembers(g.getMembers()
-                                            .stream()
-                                            .map(this::resolveSignalServiceAddress)
-                                            .collect(Collectors.toSet()));
-                                    if (!g.isActive()) {
-                                        syncGroup.removeMember(account.getSelfAddress());
-                                    } else {
-                                        // Add ourself to the member set as it's marked as active
-                                        syncGroup.addMembers(List.of(account.getSelfAddress()));
-                                    }
-                                    syncGroup.blocked = g.isBlocked();
-                                    if (g.getColor().isPresent()) {
-                                        syncGroup.color = g.getColor().get();
-                                    }
-
-                                    if (g.getAvatar().isPresent()) {
-                                        downloadGroupAvatar(g.getAvatar().get(), syncGroup.getGroupId());
-                                    }
-                                    syncGroup.inboxPosition = g.getInboxPosition().orNull();
-                                    syncGroup.archived = g.isArchived();
-                                    account.getGroupStore().updateGroup(syncGroup);
-                                }
-                            }
-                        }
-                    } catch (Exception e) {
-                        logger.warn("Failed to handle received sync groups “{}”, ignoring: {}",
-                                tmpFile,
-                                e.getMessage());
-                    } finally {
-                        if (tmpFile != null) {
-                            try {
-                                Files.delete(tmpFile.toPath());
-                            } catch (IOException e) {
-                                logger.warn("Failed to delete received groups temp file “{}”, ignoring: {}",
-                                        tmpFile,
-                                        e.getMessage());
-                            }
-                        }
-                    }
-                }
-                if (syncMessage.getBlockedList().isPresent()) {
-                    final var blockedListMessage = syncMessage.getBlockedList().get();
-                    for (var address : blockedListMessage.getAddresses()) {
-                        setContactBlocked(resolveSignalServiceAddress(address), true);
-                    }
-                    for (var groupId : blockedListMessage.getGroupIds()
-                            .stream()
-                            .map(GroupId::unknownVersion)
-                            .collect(Collectors.toSet())) {
-                        try {
-                            setGroupBlocked(groupId, true);
-                        } catch (GroupNotFoundException e) {
-                            logger.warn("BlockedListMessage contained groupID that was not found in GroupStore: {}",
-                                    groupId.toBase64());
-                        }
-                    }
-                }
-                if (syncMessage.getContacts().isPresent()) {
-                    File tmpFile = null;
-                    try {
-                        tmpFile = IOUtils.createTempFile();
-                        final var contactsMessage = syncMessage.getContacts().get();
-                        try (var attachmentAsStream = retrieveAttachmentAsStream(contactsMessage.getContactsStream()
-                                .asPointer(), tmpFile)) {
-                            var s = new DeviceContactsInputStream(attachmentAsStream);
-                            if (contactsMessage.isComplete()) {
-                                account.getContactStore().clear();
-                            }
-                            DeviceContact c;
-                            while ((c = s.read()) != null) {
-                                if (c.getAddress().matches(account.getSelfAddress()) && c.getProfileKey().isPresent()) {
-                                    account.setProfileKey(c.getProfileKey().get());
-                                }
-                                final var address = resolveSignalServiceAddress(c.getAddress());
-                                var contact = account.getContactStore().getContact(address);
-                                if (contact == null) {
-                                    contact = new ContactInfo(address);
-                                }
-                                if (c.getName().isPresent()) {
-                                    contact.name = c.getName().get();
-                                }
-                                if (c.getColor().isPresent()) {
-                                    contact.color = c.getColor().get();
-                                }
-                                if (c.getProfileKey().isPresent()) {
-                                    account.getProfileStore().storeProfileKey(address, c.getProfileKey().get());
-                                }
-                                if (c.getVerified().isPresent()) {
-                                    final var verifiedMessage = c.getVerified().get();
-                                    account.getIdentityKeyStore()
-                                            .setIdentityTrustLevel(resolveRecipientTrusted(verifiedMessage.getDestination()),
-                                                    verifiedMessage.getIdentityKey(),
-                                                    TrustLevel.fromVerifiedState(verifiedMessage.getVerified()));
-                                }
-                                if (c.getExpirationTimer().isPresent()) {
-                                    contact.messageExpirationTime = c.getExpirationTimer().get();
-                                }
-                                contact.blocked = c.isBlocked();
-                                contact.inboxPosition = c.getInboxPosition().orNull();
-                                contact.archived = c.isArchived();
-                                account.getContactStore().updateContact(contact);
-
-                                if (c.getAvatar().isPresent()) {
-                                    downloadContactAvatar(c.getAvatar().get(), contact.getAddress());
-                                }
-                            }
-                        }
-                    } catch (Exception e) {
-                        logger.warn("Failed to handle received sync contacts “{}”, ignoring: {}",
-                                tmpFile,
-                                e.getMessage());
-                    } finally {
-                        if (tmpFile != null) {
-                            try {
-                                Files.delete(tmpFile.toPath());
-                            } catch (IOException e) {
-                                logger.warn("Failed to delete received contacts temp file “{}”, ignoring: {}",
-                                        tmpFile,
-                                        e.getMessage());
-                            }
-                        }
-                    }
-                }
-                if (syncMessage.getVerified().isPresent()) {
-                    final var verifiedMessage = syncMessage.getVerified().get();
-                    account.getIdentityKeyStore()
-                            .setIdentityTrustLevel(resolveRecipientTrusted(verifiedMessage.getDestination()),
-                                    verifiedMessage.getIdentityKey(),
-                                    TrustLevel.fromVerifiedState(verifiedMessage.getVerified()));
-                }
-                if (syncMessage.getStickerPackOperations().isPresent()) {
-                    final var stickerPackOperationMessages = syncMessage.getStickerPackOperations().get();
-                    for (var m : stickerPackOperationMessages) {
-                        if (!m.getPackId().isPresent()) {
-                            continue;
-                        }
-                        var sticker = account.getStickerStore().getSticker(m.getPackId().get());
-                        if (sticker == null) {
-                            if (!m.getPackKey().isPresent()) {
-                                continue;
-                            }
-                            sticker = new Sticker(m.getPackId().get(), m.getPackKey().get());
-                        }
-                        sticker.setInstalled(!m.getType().isPresent()
-                                || m.getType().get() == StickerPackOperationMessage.Type.INSTALL);
-                        account.getStickerStore().updateSticker(sticker);
-                    }
-                }
-                if (syncMessage.getFetchType().isPresent()) {
-                    switch (syncMessage.getFetchType().get()) {
-                        case LOCAL_PROFILE:
-                            getRecipientProfile(getSelfAddress(), true);
-                        case STORAGE_MANIFEST:
-                            // TODO
-                    }
-                }
-                if (syncMessage.getKeys().isPresent()) {
-                    final var keysMessage = syncMessage.getKeys().get();
-                    if (keysMessage.getStorageService().isPresent()) {
-                        final var storageKey = keysMessage.getStorageService().get();
-                        account.setStorageKey(storageKey);
-                    }
-                }
-                if (syncMessage.getConfiguration().isPresent()) {
-                    // TODO
-                }
-            }
-        }
-        return actions;
-    }
+    List<Identity> getIdentities(RecipientIdentifier.Single recipient);
 
-    private void downloadContactAvatar(SignalServiceAttachment avatar, SignalServiceAddress address) {
-        try {
-            avatarStore.storeContactAvatar(address, outputStream -> retrieveAttachment(avatar, outputStream));
-        } catch (IOException e) {
-            logger.warn("Failed to download avatar for contact {}, ignoring: {}", address, e.getMessage());
-        }
-    }
+    boolean trustIdentityVerified(RecipientIdentifier.Single recipient, byte[] fingerprint);
 
-    private void downloadGroupAvatar(SignalServiceAttachment avatar, GroupId groupId) {
-        try {
-            avatarStore.storeGroupAvatar(groupId, outputStream -> retrieveAttachment(avatar, outputStream));
-        } catch (IOException e) {
-            logger.warn("Failed to download avatar for group {}, ignoring: {}", groupId.toBase64(), e.getMessage());
-        }
-    }
+    boolean trustIdentityVerifiedSafetyNumber(RecipientIdentifier.Single recipient, String safetyNumber);
 
-    private void downloadGroupAvatar(GroupId groupId, GroupSecretParams groupSecretParams, String cdnKey) {
-        try {
-            avatarStore.storeGroupAvatar(groupId,
-                    outputStream -> retrieveGroupV2Avatar(groupSecretParams, cdnKey, outputStream));
-        } catch (IOException e) {
-            logger.warn("Failed to download avatar for group {}, ignoring: {}", groupId.toBase64(), e.getMessage());
-        }
-    }
+    boolean trustIdentityVerifiedSafetyNumber(RecipientIdentifier.Single recipient, byte[] safetyNumber);
 
-    private void downloadProfileAvatar(
-            SignalServiceAddress address, String avatarPath, ProfileKey profileKey
-    ) {
-        try {
-            avatarStore.storeProfileAvatar(address,
-                    outputStream -> retrieveProfileAvatar(avatarPath, profileKey, outputStream));
-        } catch (Throwable e) {
-            logger.warn("Failed to download profile avatar, ignoring: {}", e.getMessage());
-        }
-    }
-
-    public File getAttachmentFile(SignalServiceAttachmentRemoteId attachmentId) {
-        return attachmentStore.getAttachmentFile(attachmentId);
-    }
+    boolean trustIdentityAllKeys(RecipientIdentifier.Single recipient);
 
-    private void downloadAttachment(final SignalServiceAttachment attachment) {
-        if (!attachment.isPointer()) {
-            logger.warn("Invalid state, can't store an attachment stream.");
-        }
-
-        var pointer = attachment.asPointer();
-        if (pointer.getPreview().isPresent()) {
-            final var preview = pointer.getPreview().get();
-            try {
-                attachmentStore.storeAttachmentPreview(pointer.getRemoteId(),
-                        outputStream -> outputStream.write(preview, 0, preview.length));
-            } catch (IOException e) {
-                logger.warn("Failed to download attachment preview, ignoring: {}", e.getMessage());
-            }
-        }
-
-        try {
-            attachmentStore.storeAttachment(pointer.getRemoteId(),
-                    outputStream -> retrieveAttachmentPointer(pointer, outputStream));
-        } catch (IOException e) {
-            logger.warn("Failed to download attachment ({}), ignoring: {}", pointer.getRemoteId(), e.getMessage());
-        }
-    }
-
-    private void retrieveGroupV2Avatar(
-            GroupSecretParams groupSecretParams, String cdnKey, OutputStream outputStream
-    ) throws IOException {
-        var groupOperations = groupsV2Operations.forGroup(groupSecretParams);
-
-        var tmpFile = IOUtils.createTempFile();
-        try (InputStream input = messageReceiver.retrieveGroupsV2ProfileAvatar(cdnKey,
-                tmpFile,
-                ServiceConfig.AVATAR_DOWNLOAD_FAILSAFE_MAX_SIZE)) {
-            var encryptedData = IOUtils.readFully(input);
-
-            var decryptedData = groupOperations.decryptAvatar(encryptedData);
-            outputStream.write(decryptedData);
-        } finally {
-            try {
-                Files.delete(tmpFile.toPath());
-            } catch (IOException e) {
-                logger.warn("Failed to delete received group avatar temp file “{}”, ignoring: {}",
-                        tmpFile,
-                        e.getMessage());
-            }
-        }
-    }
-
-    private void retrieveProfileAvatar(
-            String avatarPath, ProfileKey profileKey, OutputStream outputStream
-    ) throws IOException {
-        var tmpFile = IOUtils.createTempFile();
-        try (var input = messageReceiver.retrieveProfileAvatar(avatarPath,
-                tmpFile,
-                profileKey,
-                ServiceConfig.AVATAR_DOWNLOAD_FAILSAFE_MAX_SIZE)) {
-            // Use larger buffer size to prevent AssertionError: Need: 12272 but only have: 8192 ...
-            IOUtils.copyStream(input, outputStream, (int) ServiceConfig.AVATAR_DOWNLOAD_FAILSAFE_MAX_SIZE);
-        } finally {
-            try {
-                Files.delete(tmpFile.toPath());
-            } catch (IOException e) {
-                logger.warn("Failed to delete received profile avatar temp file “{}”, ignoring: {}",
-                        tmpFile,
-                        e.getMessage());
-            }
-        }
-    }
-
-    private void retrieveAttachment(
-            final SignalServiceAttachment attachment, final OutputStream outputStream
-    ) throws IOException {
-        if (attachment.isPointer()) {
-            var pointer = attachment.asPointer();
-            retrieveAttachmentPointer(pointer, outputStream);
-        } else {
-            var stream = attachment.asStream();
-            IOUtils.copyStream(stream.getInputStream(), outputStream);
-        }
-    }
-
-    private void retrieveAttachmentPointer(
-            SignalServiceAttachmentPointer pointer, OutputStream outputStream
-    ) throws IOException {
-        var tmpFile = IOUtils.createTempFile();
-        try (var input = retrieveAttachmentAsStream(pointer, tmpFile)) {
-            IOUtils.copyStream(input, outputStream);
-        } catch (MissingConfigurationException | InvalidMessageException e) {
-            throw new IOException(e);
-        } finally {
-            try {
-                Files.delete(tmpFile.toPath());
-            } catch (IOException e) {
-                logger.warn("Failed to delete received attachment temp file “{}”, ignoring: {}",
-                        tmpFile,
-                        e.getMessage());
-            }
-        }
-    }
-
-    private InputStream retrieveAttachmentAsStream(
-            SignalServiceAttachmentPointer pointer, File tmpFile
-    ) throws IOException, InvalidMessageException, MissingConfigurationException {
-        return messageReceiver.retrieveAttachment(pointer, tmpFile, ServiceConfig.MAX_ATTACHMENT_SIZE);
-    }
-
-    void sendGroups() throws IOException, UntrustedIdentityException {
-        var groupsFile = IOUtils.createTempFile();
-
-        try {
-            try (OutputStream fos = new FileOutputStream(groupsFile)) {
-                var out = new DeviceGroupsOutputStream(fos);
-                for (var record : getGroups()) {
-                    if (record instanceof GroupInfoV1) {
-                        var groupInfo = (GroupInfoV1) record;
-                        out.write(new DeviceGroup(groupInfo.getGroupId().serialize(),
-                                Optional.fromNullable(groupInfo.name),
-                                new ArrayList<>(groupInfo.getMembers()),
-                                createGroupAvatarAttachment(groupInfo.getGroupId()),
-                                groupInfo.isMember(account.getSelfAddress()),
-                                Optional.of(groupInfo.messageExpirationTime),
-                                Optional.fromNullable(groupInfo.color),
-                                groupInfo.blocked,
-                                Optional.fromNullable(groupInfo.inboxPosition),
-                                groupInfo.archived));
-                    }
-                }
-            }
-
-            if (groupsFile.exists() && groupsFile.length() > 0) {
-                try (var groupsFileStream = new FileInputStream(groupsFile)) {
-                    var attachmentStream = SignalServiceAttachment.newStreamBuilder()
-                            .withStream(groupsFileStream)
-                            .withContentType("application/octet-stream")
-                            .withLength(groupsFile.length())
-                            .build();
-
-                    sendSyncMessage(SignalServiceSyncMessage.forGroups(attachmentStream));
-                }
-            }
-        } finally {
-            try {
-                Files.delete(groupsFile.toPath());
-            } catch (IOException e) {
-                logger.warn("Failed to delete groups temp file “{}”, ignoring: {}", groupsFile, e.getMessage());
-            }
-        }
-    }
-
-    public void sendContacts() throws IOException, UntrustedIdentityException {
-        var contactsFile = IOUtils.createTempFile();
-
-        try {
-            try (OutputStream fos = new FileOutputStream(contactsFile)) {
-                var out = new DeviceContactsOutputStream(fos);
-                for (var record : account.getContactStore().getContacts()) {
-                    VerifiedMessage verifiedMessage = null;
-                    var currentIdentity = account.getIdentityKeyStore()
-                            .getIdentity(resolveRecipientTrusted(record.getAddress()));
-                    if (currentIdentity != null) {
-                        verifiedMessage = new VerifiedMessage(record.getAddress(),
-                                currentIdentity.getIdentityKey(),
-                                currentIdentity.getTrustLevel().toVerifiedState(),
-                                currentIdentity.getDateAdded().getTime());
-                    }
-
-                    var profileKey = account.getProfileStore().getProfileKey(record.getAddress());
-                    out.write(new DeviceContact(record.getAddress(),
-                            Optional.fromNullable(record.name),
-                            createContactAvatarAttachment(record.getAddress()),
-                            Optional.fromNullable(record.color),
-                            Optional.fromNullable(verifiedMessage),
-                            Optional.fromNullable(profileKey),
-                            record.blocked,
-                            Optional.of(record.messageExpirationTime),
-                            Optional.fromNullable(record.inboxPosition),
-                            record.archived));
-                }
-
-                if (account.getProfileKey() != null) {
-                    // Send our own profile key as well
-                    out.write(new DeviceContact(account.getSelfAddress(),
-                            Optional.absent(),
-                            Optional.absent(),
-                            Optional.absent(),
-                            Optional.absent(),
-                            Optional.of(account.getProfileKey()),
-                            false,
-                            Optional.absent(),
-                            Optional.absent(),
-                            false));
-                }
-            }
-
-            if (contactsFile.exists() && contactsFile.length() > 0) {
-                try (var contactsFileStream = new FileInputStream(contactsFile)) {
-                    var attachmentStream = SignalServiceAttachment.newStreamBuilder()
-                            .withStream(contactsFileStream)
-                            .withContentType("application/octet-stream")
-                            .withLength(contactsFile.length())
-                            .build();
-
-                    sendSyncMessage(SignalServiceSyncMessage.forContacts(new ContactsMessage(attachmentStream, true)));
-                }
-            }
-        } finally {
-            try {
-                Files.delete(contactsFile.toPath());
-            } catch (IOException e) {
-                logger.warn("Failed to delete contacts temp file “{}”, ignoring: {}", contactsFile, e.getMessage());
-            }
-        }
-    }
-
-    void sendBlockedList() throws IOException, UntrustedIdentityException {
-        var addresses = new ArrayList<SignalServiceAddress>();
-        for (var record : account.getContactStore().getContacts()) {
-            if (record.blocked) {
-                addresses.add(record.getAddress());
-            }
-        }
-        var groupIds = new ArrayList<byte[]>();
-        for (var record : getGroups()) {
-            if (record.isBlocked()) {
-                groupIds.add(record.getGroupId().serialize());
-            }
-        }
-        sendSyncMessage(SignalServiceSyncMessage.forBlocked(new BlockedListMessage(addresses, groupIds)));
-    }
-
-    private void sendVerifiedMessage(
-            SignalServiceAddress destination, IdentityKey identityKey, TrustLevel trustLevel
-    ) throws IOException, UntrustedIdentityException {
-        var verifiedMessage = new VerifiedMessage(destination,
-                identityKey,
-                trustLevel.toVerifiedState(),
-                System.currentTimeMillis());
-        sendSyncMessage(SignalServiceSyncMessage.forVerified(verifiedMessage));
-    }
-
-    public List<ContactInfo> getContacts() {
-        return account.getContactStore().getContacts();
-    }
-
-    public String getContactOrProfileName(String number) {
-        final var address = Utils.getSignalServiceAddressFromIdentifier(number);
-
-        final var contact = account.getContactStore().getContact(address);
-        if (contact != null && !Util.isEmpty(contact.name)) {
-            return contact.name;
-        }
-
-        final var profileEntry = account.getProfileStore().getProfileEntry(address);
-        if (profileEntry != null && profileEntry.getProfile() != null) {
-            return profileEntry.getProfile().getDisplayName();
-        }
-        return null;
-    }
-
-    public GroupInfo getGroup(GroupId groupId) {
-        final var group = account.getGroupStore().getGroup(groupId);
-        if (group instanceof GroupInfoV2 && ((GroupInfoV2) group).getGroup() == null) {
-            final var groupSecretParams = GroupSecretParams.deriveFromMasterKey(((GroupInfoV2) group).getMasterKey());
-            ((GroupInfoV2) group).setGroup(groupHelper.getDecryptedGroup(groupSecretParams));
-            account.getGroupStore().updateGroup(group);
-        }
-        return group;
-    }
-
-    public List<IdentityInfo> getIdentities() {
-        return account.getIdentityKeyStore().getIdentities();
-    }
-
-    public List<IdentityInfo> getIdentities(String number) throws InvalidNumberException {
-        final var identity = account.getIdentityKeyStore().getIdentity(canonicalizeAndResolveRecipient(number));
-        return identity == null ? List.of() : List.of(identity);
-    }
-
-    /**
-     * Trust this the identity with this fingerprint
-     *
-     * @param name        username of the identity
-     * @param fingerprint Fingerprint
-     */
-    public boolean trustIdentityVerified(String name, byte[] fingerprint) throws InvalidNumberException {
-        var recipientId = canonicalizeAndResolveRecipient(name);
-        return trustIdentity(recipientId,
-                identityKey -> Arrays.equals(identityKey.serialize(), fingerprint),
-                TrustLevel.TRUSTED_VERIFIED);
-    }
-
-    /**
-     * Trust this the identity with this safety number
-     *
-     * @param name         username of the identity
-     * @param safetyNumber Safety number
-     */
-    public boolean trustIdentityVerifiedSafetyNumber(String name, String safetyNumber) throws InvalidNumberException {
-        var recipientId = canonicalizeAndResolveRecipient(name);
-        var address = account.getRecipientStore().resolveServiceAddress(recipientId);
-        return trustIdentity(recipientId,
-                identityKey -> safetyNumber.equals(computeSafetyNumber(address, identityKey)),
-                TrustLevel.TRUSTED_VERIFIED);
-    }
-
-    /**
-     * Trust all keys of this identity without verification
-     *
-     * @param name username of the identity
-     */
-    public boolean trustIdentityAllKeys(String name) throws InvalidNumberException {
-        var recipientId = canonicalizeAndResolveRecipient(name);
-        return trustIdentity(recipientId, identityKey -> true, TrustLevel.TRUSTED_UNVERIFIED);
-    }
-
-    private boolean trustIdentity(
-            RecipientId recipientId, Function<IdentityKey, Boolean> verifier, TrustLevel trustLevel
-    ) {
-        var identity = account.getIdentityKeyStore().getIdentity(recipientId);
-        if (identity == null) {
-            return false;
-        }
-
-        if (!verifier.apply(identity.getIdentityKey())) {
-            return false;
-        }
-
-        account.getIdentityKeyStore().setIdentityTrustLevel(recipientId, identity.getIdentityKey(), trustLevel);
-        try {
-            var address = account.getRecipientStore().resolveServiceAddress(recipientId);
-            sendVerifiedMessage(address, identity.getIdentityKey(), trustLevel);
-        } catch (IOException | UntrustedIdentityException e) {
-            logger.warn("Failed to send verification sync message: {}", e.getMessage());
-        }
-
-        return true;
-    }
-
-    public String computeSafetyNumber(
-            SignalServiceAddress theirAddress, IdentityKey theirIdentityKey
-    ) {
-        return Utils.computeSafetyNumber(ServiceConfig.capabilities.isUuid(),
-                account.getSelfAddress(),
-                getIdentityKeyPair().getPublicKey(),
-                theirAddress,
-                theirIdentityKey);
-    }
-
-    @Deprecated
-    public SignalServiceAddress canonicalizeAndResolveSignalServiceAddress(String identifier) throws InvalidNumberException {
-        var canonicalizedNumber = UuidUtil.isUuid(identifier)
-                ? identifier
-                : PhoneNumberFormatter.formatNumber(identifier, account.getUsername());
-        return resolveSignalServiceAddress(canonicalizedNumber);
-    }
-
-    @Deprecated
-    public SignalServiceAddress resolveSignalServiceAddress(String identifier) {
-        var address = Utils.getSignalServiceAddressFromIdentifier(identifier);
-
-        return resolveSignalServiceAddress(address);
-    }
-
-    @Deprecated
-    public SignalServiceAddress resolveSignalServiceAddress(SignalServiceAddress address) {
-        if (address.matches(account.getSelfAddress())) {
-            return account.getSelfAddress();
-        }
-
-        return account.getRecipientStore().resolveServiceAddress(address);
-    }
-
-    public SignalServiceAddress resolveSignalServiceAddress(RecipientId recipientId) {
-        return account.getRecipientStore().resolveServiceAddress(recipientId);
-    }
-
-    public RecipientId canonicalizeAndResolveRecipient(String identifier) throws InvalidNumberException {
-        var canonicalizedNumber = UuidUtil.isUuid(identifier)
-                ? identifier
-                : PhoneNumberFormatter.formatNumber(identifier, account.getUsername());
-
-        return resolveRecipient(canonicalizedNumber);
-    }
-
-    private RecipientId resolveRecipient(final String identifier) {
-        var address = Utils.getSignalServiceAddressFromIdentifier(identifier);
-
-        return resolveRecipient(address);
-    }
-
-    public RecipientId resolveRecipient(SignalServiceAddress address) {
-        return account.getRecipientStore().resolveRecipientUntrusted(address);
-    }
-
-    private RecipientId resolveRecipientTrusted(SignalServiceAddress address) {
-        return account.getRecipientStore().resolveRecipient(address);
-    }
+    SignalServiceAddress resolveSignalServiceAddress(SignalServiceAddress address);
 
     @Override
-    public void close() throws IOException {
-        close(true);
-    }
-
-    void close(boolean closeAccount) throws IOException {
-        executor.shutdown();
-
-        if (messagePipe != null) {
-            messagePipe.shutdown();
-            messagePipe = null;
-        }
-
-        if (unidentifiedMessagePipe != null) {
-            unidentifiedMessagePipe.shutdown();
-            unidentifiedMessagePipe = null;
-        }
-
-        if (closeAccount && account != null) {
-            account.close();
-        }
-        account = null;
-    }
+    void close() throws IOException;
 
-    public interface ReceiveMessageHandler {
+    interface ReceiveMessageHandler {
 
         void handleMessage(SignalServiceEnvelope envelope, SignalServiceContent decryptedContent, Throwable e);
     }