Add method for unpairing to MailboxManager

bramble-api/src/main/java/org/briarproject/bramble/api/mailbox/MailboxManager.java

@@ -2,6 +2,7 @@ package org.briarproject.bramble.api.mailbox;
 
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
+import org.briarproject.bramble.api.lifecycle.IoExecutor;
 
 import javax.annotation.Nullable;
 
@@ -41,4 +42,10 @@ public interface MailboxManager {
 	 */
 	boolean checkConnection();
 
+	/**
+	 * Unpairs the owner's mailbox and tries to wipe it.
+	 * As this makes a network call, it should be run on the {@link IoExecutor}.
+	 */
+	@IoExecutor
+	void unPair() throws DbException;
 }

bramble-api/src/main/java/org/briarproject/bramble/api/mailbox/MailboxSettingsManager.java

@@ -26,6 +26,8 @@ public interface MailboxSettingsManager {
 	void setOwnMailboxProperties(Transaction txn, MailboxProperties p)
 			throws DbException;
 
+	void removeOwnMailboxProperties(Transaction txn) throws DbException;
+
 	MailboxStatus getOwnMailboxStatus(Transaction txn) throws DbException;
 
 	void recordSuccessfulConnection(Transaction txn, long now)

bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxManagerImpl.java

@@ -131,4 +131,18 @@ class MailboxManagerImpl implements MailboxManager {
 		});
 	}
 
+	@Override
+	public void unPair() throws DbException {
+		MailboxProperties properties = db.transactionWithNullableResult(true,
+				mailboxSettingsManager::getOwnMailboxProperties);
+		try {
+			api.wipeMailbox(properties);
+		} catch (IOException | MailboxApi.ApiException e) {
+			// We wipe on a best-effort basis.
+			// If we can't do it, we still unpair.
+			logException(LOG, WARNING, e);
+		}
+		db.transaction(false,
+				mailboxSettingsManager::removeOwnMailboxProperties);
+	}
 }

bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxSettingsManagerImpl.java

@@ -75,6 +75,17 @@ class MailboxSettingsManagerImpl implements MailboxSettingsManager {
 		}
 	}
 
+	@Override
+	public void removeOwnMailboxProperties(Transaction txn) throws DbException {
+		Settings s = new Settings();
+		s.put(SETTINGS_KEY_ONION, "");
+		s.put(SETTINGS_KEY_TOKEN, "");
+		settingsManager.mergeSettings(txn, s, SETTINGS_NAMESPACE);
+		for (MailboxHook hook : hooks) {
+			hook.mailboxUnpaired(txn);
+		}
+	}
+
 	@Override
 	public MailboxStatus getOwnMailboxStatus(Transaction txn)
 			throws DbException {