Refactor and create a RestoreAccount class which does the combining

briar-api/src/main/java/org/briarproject/briar/api/socialbackup/SocialBackup.java

@@ -6,10 +6,10 @@ import java.util.List;
 
 public class SocialBackup {
 	private Identity identity;
-	private List<ContactData> contacts;
+	private List<org.briarproject.briar.api.socialbackup.ContactData> contacts;
 	private int version;
 
-	SocialBackup (Identity identity, List<ContactData> contacts, int version) {
+	SocialBackup (Identity identity, List<org.briarproject.briar.api.socialbackup.ContactData> contacts, int version) {
 		this.identity = identity;
 		this.contacts = contacts;
 		this.version = version;
@@ -19,7 +19,7 @@ public class SocialBackup {
 		return identity;
 	}
 
-	public List<ContactData> getContacts() {
+	public List<org.briarproject.briar.api.socialbackup.ContactData> getContacts() {
 		return contacts;
 	}
 

briar-api/src/main/java/org/briarproject/briar/api/socialbackup/recovery/RestoreAccount.java

@@ -0,0 +1,4 @@
+package org.briarproject.briar.api.socialbackup.recovery;
+
+public interface RestoreAccount {
+}

briar-core/src/main/java/org/briarproject/briar/socialbackup/BackupPayloadDecoder.java

@@ -4,6 +4,7 @@ import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.briar.api.socialbackup.BackupPayload;
+import org.briarproject.briar.api.socialbackup.SocialBackup;
 
 import java.security.GeneralSecurityException;
 

briar-core/src/main/java/org/briarproject/briar/socialbackup/BackupPayloadDecoderImpl.java

@@ -20,6 +20,7 @@ import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.briar.api.socialbackup.BackupPayload;
 import org.briarproject.briar.api.socialbackup.MessageParser;
 import org.briarproject.briar.api.socialbackup.Shard;
+import org.briarproject.briar.api.socialbackup.SocialBackup;
 
 import java.security.GeneralSecurityException;
 import java.security.SecureRandom;
@@ -54,7 +55,7 @@ public class BackupPayloadDecoderImpl implements BackupPayloadDecoder {
 		this.messageParser = messageParser;
 	}
 
-	public SocialBackup decodeBackupPayload(
+	public org.briarproject.briar.api.socialbackup.SocialBackup decodeBackupPayload(
 			SecretKey secret,
 			BackupPayload backupPayload)
 			throws FormatException, GeneralSecurityException {
@@ -103,7 +104,7 @@ public class BackupPayloadDecoderImpl implements BackupPayloadDecoder {
 				handShakePrivateKey, created);
 		LOG.info("New identity created");
 
-		List<ContactData> contactDataList = new ArrayList();
+		List<org.briarproject.briar.api.socialbackup.ContactData> contactDataList = new ArrayList();
 
 		for (int i = 0; i < bdfContactData.size(); i++) {
 			BdfList bdfData = bdfContactData.getList(i);
@@ -139,8 +140,8 @@ public class BackupPayloadDecoderImpl implements BackupPayloadDecoder {
 			Contact contact =
 					new Contact(contactId, author, author.getId(), alias,
 							contactHandshakePublicKey, false);
-			ContactData contactData =
+			org.briarproject.briar.api.socialbackup.ContactData contactData =
-					new ContactData(contact, properties, shard);
+					new org.briarproject.briar.api.socialbackup.ContactData(contact, properties, shard);
 			contactDataList.add(contactData);
 			LOG.info("Contact added");
 		}

briar-core/src/main/java/org/briarproject/briar/socialbackup/BackupPayloadEncoder.java

@@ -10,5 +10,5 @@ import java.util.List;
 interface BackupPayloadEncoder {
 
 	org.briarproject.briar.api.socialbackup.BackupPayload encodeBackupPayload(SecretKey secret, Identity identity,
-			List<ContactData> contactData, int version);
+			List<org.briarproject.briar.api.socialbackup.ContactData> contactData, int version);
 }

briar-core/src/main/java/org/briarproject/briar/socialbackup/BackupPayloadEncoderImpl.java

@@ -46,7 +46,7 @@ class BackupPayloadEncoderImpl implements BackupPayloadEncoder {
 
 	@Override
 	public org.briarproject.briar.api.socialbackup.BackupPayload encodeBackupPayload(SecretKey secret,
-			Identity identity, List<ContactData> contactData, int version) {
+			Identity identity, List<org.briarproject.briar.api.socialbackup.ContactData> contactData, int version) {
 		// Encode the local identity
 		BdfList bdfIdentity = new BdfList();
 		LocalAuthor localAuthor = identity.getLocalAuthor();
@@ -56,7 +56,7 @@ class BackupPayloadEncoderImpl implements BackupPayloadEncoder {
 		bdfIdentity.add(identity.getHandshakePrivateKey().getEncoded());
 		// Encode the contact data
 		BdfList bdfContactData = new BdfList();
-		for (ContactData cd : contactData) {
+		for (org.briarproject.briar.api.socialbackup.ContactData cd : contactData) {
 			BdfList bdfData = new BdfList();
 			Contact contact = cd.getContact();
 			bdfData.add(clientHelper.toList(contact.getAuthor()));

briar-core/src/main/java/org/briarproject/briar/socialbackup/SocialBackupManagerImpl.java

@@ -193,12 +193,12 @@ class SocialBackupManagerImpl extends ConversationClientImpl
 			// Add the shard to our backup, if any
 			if (localBackupExists(txn)) {
 				Shard shard = messageParser.parseShardMessage(body);
-				List<ContactData> contactData = loadContactData(txn);
+				List<org.briarproject.briar.api.socialbackup.ContactData> contactData = loadContactData(txn);
-				ListIterator<ContactData> it = contactData.listIterator();
+				ListIterator<org.briarproject.briar.api.socialbackup.ContactData> it = contactData.listIterator();
 				while (it.hasNext()) {
-					ContactData cd = it.next();
+					org.briarproject.briar.api.socialbackup.ContactData cd = it.next();
 					if (cd.getContact().getId().equals(contactId)) {
-						it.set(new ContactData(cd.getContact(),
+						it.set(new org.briarproject.briar.api.socialbackup.ContactData(cd.getContact(),
 								cd.getProperties(), shard));
 						updateBackup(txn, contactData);
 						break;
@@ -278,7 +278,7 @@ class SocialBackupManagerImpl extends ConversationClientImpl
 		}
 		// Create the encrypted backup payload
 		SecretKey secret = crypto.generateSecretKey();
-		List<ContactData> contactData = loadContactData(txn);
+		List<org.briarproject.briar.api.socialbackup.ContactData> contactData = loadContactData(txn);
 		BackupPayload payload =
 				createBackupPayload(txn, secret, contactData, 0);
 		// Create the shards
@@ -415,17 +415,17 @@ class SocialBackupManagerImpl extends ConversationClientImpl
 	}
 
 	private BackupPayload createBackupPayload(Transaction txn,
-			SecretKey secret, List<ContactData> contactData, int version)
+			SecretKey secret, List<org.briarproject.briar.api.socialbackup.ContactData> contactData, int version)
 			throws DbException {
 		Identity identity = identityManager.getIdentity(txn);
 		return backupPayloadEncoder.encodeBackupPayload(secret, identity,
 				contactData, version);
 	}
 
-	private List<ContactData> loadContactData(Transaction txn)
+	private List<org.briarproject.briar.api.socialbackup.ContactData> loadContactData(Transaction txn)
 			throws DbException {
 		Collection<Contact> contacts = contactManager.getContacts(txn);
-		List<ContactData> contactData = new ArrayList<>();
+		List<org.briarproject.briar.api.socialbackup.ContactData> contactData = new ArrayList<>();
 		for (Contact c : contacts) {
 			// Skip contacts that are in the process of being removed
 			Group contactGroup = getContactGroup(c);
@@ -433,7 +433,7 @@ class SocialBackupManagerImpl extends ConversationClientImpl
 			Map<TransportId, TransportProperties> props =
 					getTransportProperties(txn, c.getId());
 			Shard shard = getRemoteShard(txn, contactGroup.getId());
-			contactData.add(new ContactData(c, props, shard));
+			contactData.add(new org.briarproject.briar.api.socialbackup.ContactData(c, props, shard));
 		}
 		return contactData;
 	}
@@ -513,7 +513,7 @@ class SocialBackupManagerImpl extends ConversationClientImpl
 			throw new DbException(e);
 		}
 	}
-	private void updateBackup(Transaction txn, List<ContactData> contactData)
+	private void updateBackup(Transaction txn, List<org.briarproject.briar.api.socialbackup.ContactData> contactData)
 			throws DbException {
 		BackupMetadata backupMetadata = requireNonNull(getBackupMetadata(txn));
 		int newVersion = backupMetadata.getVersion() + 1;

briar-core/src/main/java/org/briarproject/briar/socialbackup/SocialBackupModule.java

@@ -11,8 +11,10 @@ import org.briarproject.briar.api.conversation.ConversationManager;
 import org.briarproject.briar.api.socialbackup.SocialBackupExchangeManager;
 import org.briarproject.briar.api.socialbackup.SocialBackupManager;
 import org.briarproject.briar.api.socialbackup.recovery.CustodianTask;
+import org.briarproject.briar.api.socialbackup.recovery.RestoreAccount;
 import org.briarproject.briar.api.socialbackup.recovery.SecretOwnerTask;
 import org.briarproject.briar.socialbackup.recovery.CustodianTaskImpl;
+import org.briarproject.briar.socialbackup.recovery.RestoreAccountImpl;
 import org.briarproject.briar.socialbackup.recovery.SecretOwnerTaskImpl;
 
 import javax.inject.Inject;
@@ -119,4 +121,9 @@ public class SocialBackupModule {
 	CustodianTask custodianTask(CustodianTaskImpl custodianTask) {
 		return custodianTask;
 	}
+
+	@Provides
+	RestoreAccount restoreAccount(RestoreAccountImpl restoreAccount) {
+		return restoreAccount;
+	}
 }

briar-core/src/main/java/org/briarproject/briar/socialbackup/recovery/RestoreAccountImpl.java

@@ -0,0 +1,73 @@
+package org.briarproject.briar.socialbackup.recovery;
+
+import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.crypto.SecretKey;
+import org.briarproject.briar.api.socialbackup.BackupPayload;
+import org.briarproject.briar.api.socialbackup.DarkCrystal;
+import org.briarproject.briar.api.socialbackup.ReturnShardPayload;
+import org.briarproject.briar.api.socialbackup.Shard;
+import org.briarproject.briar.api.socialbackup.recovery.RestoreAccount;
+import org.briarproject.briar.socialbackup.BackupPayloadDecoder;
+import org.briarproject.briar.api.socialbackup.SocialBackup;
+
+import java.security.GeneralSecurityException;
+import java.util.ArrayList;
+
+import javax.inject.Inject;
+
+public class RestoreAccountImpl implements RestoreAccount {
+	private ArrayList<ReturnShardPayload> recoveredShards = new ArrayList<>();
+	private final DarkCrystal darkCrystal;
+	private SecretKey secretKey;
+	private final BackupPayloadDecoder backupPayloadDecoder;
+	private SocialBackup socialBackup;
+
+	@Inject
+	RestoreAccountImpl(DarkCrystal darkCrystal, BackupPayloadDecoder backupPayloadDecoder) {
+		this.darkCrystal = darkCrystal;
+		this.backupPayloadDecoder = backupPayloadDecoder;
+	}
+
+	public int getNumberOfShards() { return recoveredShards.size(); }
+
+	// TODO figure out how to actually use a hash set for these objects
+	public boolean addReturnShardPayload(ReturnShardPayload toAdd) {
+		boolean found = false;
+		for (ReturnShardPayload returnShardPayload : recoveredShards) {
+			if (toAdd.equals(returnShardPayload)) {
+				found = true;
+				break;
+			}
+		}
+		if (!found) recoveredShards.add(toAdd);
+		return !found;
+	}
+
+	public boolean canRecover() {
+		ArrayList<Shard> shards = new ArrayList();
+		for (ReturnShardPayload returnShardPayload : recoveredShards) {
+			// TODO check shards all have same secret id
+			shards.add(returnShardPayload.getShard());
+		}
+		try {
+			secretKey = darkCrystal.combineShards(shards);
+		} catch (GeneralSecurityException e) {
+			// TODO handle error message
+			return false;
+		}
+		return true;
+	}
+
+	public int recover() throws FormatException, GeneralSecurityException {
+		if (secretKey == null) throw new GeneralSecurityException();
+		// TODO find backup with highest version number
+		BackupPayload backupPayload = recoveredShards.get(0).getBackupPayload();
+		socialBackup = backupPayloadDecoder.decodeBackupPayload(secretKey, backupPayload);
+		int version = socialBackup.getVersion();
+		return version;
+	}
+
+	public SocialBackup getSocialBackup() {
+		return socialBackup;
+	}
+}