Added a service based POW engine, so it shouldn't be killed by the system, at least not that easily. (WIP)

app/src/main/AndroidManifest.xml

@@ -102,7 +102,8 @@
                 <category android:name="android.intent.category.BROWSABLE" />
             </intent-filter>
         </activity>
-        <service android:name=".synchronization.BitmessageService" />
+        <service android:name=".service.BitmessageService" />
+        <service android:name=".service.ProofOfWorkService" />
 
         <!-- Synchronization -->
         <provider

app/src/main/java/ch/dissem/apps/abit/MessageListActivity.java

@@ -40,22 +40,23 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.Serializable;
+import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 
 import ch.dissem.apps.abit.listener.ActionBarListener;
 import ch.dissem.apps.abit.listener.ListSelectionListener;
+import ch.dissem.apps.abit.service.BitmessageService;
 import ch.dissem.apps.abit.service.Singleton;
 import ch.dissem.apps.abit.synchronization.Authenticator;
-import ch.dissem.apps.abit.synchronization.BitmessageService;
 import ch.dissem.bitmessage.entity.BitmessageAddress;
 import ch.dissem.bitmessage.entity.Plaintext;
 import ch.dissem.bitmessage.entity.valueobject.Label;
 import ch.dissem.bitmessage.ports.AddressRepository;
 import ch.dissem.bitmessage.ports.MessageRepository;
 
-import static ch.dissem.apps.abit.synchronization.BitmessageService.DATA_FIELD_IDENTITY;
+import static ch.dissem.apps.abit.service.BitmessageService.DATA_FIELD_IDENTITY;
-import static ch.dissem.apps.abit.synchronization.BitmessageService.MSG_START_NODE;
+import static ch.dissem.apps.abit.service.BitmessageService.MSG_START_NODE;
-import static ch.dissem.apps.abit.synchronization.BitmessageService.MSG_STOP_NODE;
+import static ch.dissem.apps.abit.service.BitmessageService.MSG_STOP_NODE;
 import static ch.dissem.apps.abit.synchronization.StubProvider.AUTHORITY;
 
 
@@ -82,7 +83,7 @@ public class MessageListActivity extends AppCompatActivity
     public static final String ACTION_SHOW_INBOX = "ch.dissem.abit.ShowInbox";
 
     private static final Logger LOG = LoggerFactory.getLogger(MessageListActivity.class);
-    private static final long SYNC_FREQUENCY = 15;// FIXME * 60; // seconds
+    private static final long SYNC_FREQUENCY = 15 * 60; // seconds
     private static final int ADD_IDENTITY = 1;
 
     /**
@@ -91,14 +92,15 @@ public class MessageListActivity extends AppCompatActivity
      */
     private boolean twoPane;
 
-    private Messenger messenger = new Messenger(new IncomingHandler());
+    private static IncomingHandler incomingHandler = new IncomingHandler();
-    private Messenger service;
+    private static Messenger messenger = new Messenger(incomingHandler);
-    private boolean bound;
+    private static Messenger service;
-    private ServiceConnection connection = new ServiceConnection() {
+    private static boolean bound;
+    private static ServiceConnection connection = new ServiceConnection() {
         @Override
         public void onServiceConnected(ComponentName name, IBinder service) {
-            MessageListActivity.this.service = new Messenger(service);
+            MessageListActivity.service = new Messenger(service);
-            MessageListActivity.this.bound = true;
+            MessageListActivity.bound = true;
         }
 
         @Override
@@ -108,7 +110,6 @@ public class MessageListActivity extends AppCompatActivity
         }
     };
 
-    private AccountHeader accountHeader;
     private Label selectedLabel;
 
     private MessageRepository messageRepo;
@@ -208,7 +209,7 @@ public class MessageListActivity extends AppCompatActivity
                         .withIcon(GoogleMaterial.Icon.gmd_settings)
         );
         // Create the AccountHeader
-        accountHeader = new AccountHeaderBuilder()
+        AccountHeader accountHeader = new AccountHeaderBuilder()
                 .withActivity(this)
                 .withHeaderBackground(R.drawable.header)
                 .withProfiles(profiles)
@@ -229,6 +230,7 @@ public class MessageListActivity extends AppCompatActivity
                     }
                 })
                 .build();
+        incomingHandler.updateAccountHeader(accountHeader);
 
         ArrayList<IDrawerItem> drawerItems = new ArrayList<>();
         for (Label label : messageRepo.getLabels()) {
@@ -414,11 +416,24 @@ public class MessageListActivity extends AppCompatActivity
         super.onStop();
     }
 
-    private class IncomingHandler extends Handler {
+    private static class IncomingHandler extends Handler {
+        private WeakReference<AccountHeader> accountHeaderRef;
+
+        private IncomingHandler() {
+            accountHeaderRef = new WeakReference<>(null);
+        }
+
+        public void updateAccountHeader(AccountHeader accountHeader){
+            accountHeaderRef = new WeakReference<>(accountHeader);
+        }
+
         @Override
         public void handleMessage(Message msg) {
             switch (msg.what) {
                 case BitmessageService.MSG_CREATE_IDENTITY: {
+                    AccountHeader accountHeader = accountHeaderRef.get();
+                    if (accountHeader == null) break;
+
                     Serializable data = msg.getData().getSerializable(DATA_FIELD_IDENTITY);
                     if (data instanceof BitmessageAddress) {
                         BitmessageAddress identity = (BitmessageAddress) data;

app/src/main/java/ch/dissem/apps/abit/OpenBitmessageLinkActivity.java

@@ -37,13 +37,13 @@ import android.widget.TextView;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import ch.dissem.apps.abit.synchronization.BitmessageService;
+import ch.dissem.apps.abit.service.BitmessageService;
 import ch.dissem.bitmessage.entity.BitmessageAddress;
 
-import static ch.dissem.apps.abit.synchronization.BitmessageService.DATA_FIELD_ADDRESS;
+import static ch.dissem.apps.abit.service.BitmessageService.DATA_FIELD_ADDRESS;
-import static ch.dissem.apps.abit.synchronization.BitmessageService.MSG_ADD_CONTACT;
+import static ch.dissem.apps.abit.service.BitmessageService.MSG_ADD_CONTACT;
-import static ch.dissem.apps.abit.synchronization.BitmessageService.MSG_SUBSCRIBE;
+import static ch.dissem.apps.abit.service.BitmessageService.MSG_SUBSCRIBE;
-import static ch.dissem.apps.abit.synchronization.BitmessageService.MSG_SUBSCRIBE_AND_ADD_CONTACT;
+import static ch.dissem.apps.abit.service.BitmessageService.MSG_SUBSCRIBE_AND_ADD_CONTACT;
 
 public class OpenBitmessageLinkActivity extends AppCompatActivity {
     private static final Logger LOG = LoggerFactory.getLogger(OpenBitmessageLinkActivity.class);

app/src/main/java/ch/dissem/apps/abit/notification/AbstractNotification.java

@@ -14,7 +14,7 @@ public abstract class AbstractNotification {
 
 
     public AbstractNotification(Context ctx) {
-        this.ctx = ctx;
+        this.ctx = ctx.getApplicationContext();
         this.manager = (NotificationManager) ctx.getSystemService(Context.NOTIFICATION_SERVICE);
     }
 
@@ -23,6 +23,10 @@ public abstract class AbstractNotification {
      */
     protected abstract int getNotificationId();
 
+    public Notification getNotification() {
+        return notification;
+    }
+
     public void show() {
         manager.notify(getNotificationId(), notification);
     }

app/src/main/java/ch/dissem/apps/abit/notification/ErrorNotification.java

@@ -1,6 +1,7 @@
 package ch.dissem.apps.abit.notification;
 
 import android.content.Context;
+import android.support.annotation.StringRes;
 import android.support.v7.app.NotificationCompat;
 
 import ch.dissem.apps.abit.R;
@@ -20,14 +21,14 @@ public class ErrorNotification extends AbstractNotification {
                 .setVisibility(NotificationCompat.VISIBILITY_PUBLIC);
     }
 
-    public ErrorNotification setWarning(int resId, Object... args) {
+    public ErrorNotification setWarning(@StringRes int resId, Object... args) {
         builder.setSmallIcon(R.drawable.ic_notification_warning)
                 .setContentText(ctx.getString(resId, args));
         notification = builder.build();
         return this;
     }
 
-    public ErrorNotification setError(int resId, Object... args) {
+    public ErrorNotification setError(@StringRes int resId, Object... args) {
         builder.setSmallIcon(R.drawable.ic_notification_error)
                 .setContentText(ctx.getString(resId, args));
         notification = builder.build();

app/src/main/java/ch/dissem/apps/abit/notification/NetworkNotification.java

@@ -12,7 +12,6 @@ import java.util.TimerTask;
 
 import ch.dissem.apps.abit.MessageListActivity;
 import ch.dissem.apps.abit.R;
-import ch.dissem.apps.abit.service.Singleton;
 import ch.dissem.bitmessage.BitmessageContext;
 import ch.dissem.bitmessage.utils.Property;
 
@@ -26,7 +25,7 @@ public class NetworkNotification extends AbstractNotification {
     private NotificationCompat.Builder builder;
 
     public NetworkNotification(Context ctx, BitmessageContext bmc) {
-        super(ctx.getApplicationContext());
+        super(ctx);
         this.bmc = bmc;
         builder = new NotificationCompat.Builder(ctx);
         builder.setSmallIcon(R.drawable.ic_notification_full_node)
@@ -34,6 +33,7 @@ public class NetworkNotification extends AbstractNotification {
                 .setVisibility(NotificationCompat.VISIBILITY_PUBLIC);
     }
 
+    @Override
     public Notification getNotification() {
         update();
         return notification;

app/src/main/java/ch/dissem/apps/abit/notification/ProofOfWorkNotification.java

@@ -0,0 +1,38 @@
+package ch.dissem.apps.abit.notification;
+
+import android.app.PendingIntent;
+import android.content.Context;
+import android.content.Intent;
+import android.support.v7.app.NotificationCompat;
+
+import ch.dissem.apps.abit.MessageListActivity;
+import ch.dissem.apps.abit.R;
+
+/**
+ * Ongoing notification while proof of work is in progress.
+ */
+public class ProofOfWorkNotification extends AbstractNotification {
+    public static final int ONGOING_NOTIFICATION_ID = 3;
+
+    public ProofOfWorkNotification(Context ctx) {
+        super(ctx);
+        NotificationCompat.Builder builder = new NotificationCompat.Builder(ctx);
+
+        Intent showMessageIntent = new Intent(ctx, MessageListActivity.class);
+        PendingIntent pendingIntent = PendingIntent.getActivity(ctx, 0, showMessageIntent, PendingIntent.FLAG_UPDATE_CURRENT);
+
+        builder.setVisibility(NotificationCompat.VISIBILITY_PUBLIC)
+                .setUsesChronometer(true)
+                .setSmallIcon(R.drawable.ic_notification_proof_of_work)
+                .setContentTitle(ctx.getString(R.string.proof_of_work_title))
+                .setContentText(ctx.getString(R.string.proof_of_work_text))
+                .setContentIntent(pendingIntent);
+
+        notification = builder.build();
+    }
+
+    @Override
+    protected int getNotificationId() {
+        return ONGOING_NOTIFICATION_ID;
+    }
+}

app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java

@@ -1,25 +1,21 @@
-package ch.dissem.apps.abit.synchronization;
+package ch.dissem.apps.abit.service;
 
 import android.app.Service;
 import android.content.Intent;
-import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.IBinder;
 import android.os.Message;
 import android.os.Messenger;
 import android.os.RemoteException;
-import android.preference.PreferenceManager;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.Serializable;
-import java.net.InetAddress;
+import java.lang.ref.WeakReference;
-import java.net.UnknownHostException;
 
 import ch.dissem.apps.abit.notification.NetworkNotification;
-import ch.dissem.apps.abit.service.Singleton;
 import ch.dissem.bitmessage.BitmessageContext;
 import ch.dissem.bitmessage.entity.BitmessageAddress;
 
@@ -33,7 +29,6 @@ import static ch.dissem.apps.abit.notification.NetworkNotification.ONGOING_NOTIF
 public class BitmessageService extends Service {
     public static final Logger LOG = LoggerFactory.getLogger(BitmessageService.class);
 
-    public static final int MSG_SYNC = 2;
     public static final int MSG_CREATE_IDENTITY = 10;
     public static final int MSG_SUBSCRIBE = 20;
     public static final int MSG_ADD_CONTACT = 21;
@@ -68,7 +63,7 @@ public class BitmessageService extends Service {
             if (bmc == null) {
                 bmc = Singleton.getBitmessageContext(this);
                 notification = new NetworkNotification(this, bmc);
-                messenger = new Messenger(new IncomingHandler());
+                messenger = new Messenger(new IncomingHandler(this));
             }
         }
     }
@@ -93,7 +88,13 @@ public class BitmessageService extends Service {
         return messenger.getBinder();
     }
 
-    private class IncomingHandler extends Handler {
+    private static class IncomingHandler extends Handler {
+        private WeakReference<BitmessageService> service;
+
+        private IncomingHandler(BitmessageService service) {
+            this.service = new WeakReference<>(service);
+        }
+
         @Override
         public void handleMessage(Message msg) {
             switch (msg.what) {
@@ -119,45 +120,6 @@ public class BitmessageService extends Service {
                     }
                     break;
                 }
-                case MSG_SYNC: {
-                    LOG.info("Synchronizing Bitmessage");
-                    // If the Bitmessage context acts as a full node, synchronization isn't necessary
-                    if (bmc.isRunning()) break;
-
-                    SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(
-                            BitmessageService.this);
-
-                    String trustedNode = preferences.getString("trusted_node", null);
-                    if (trustedNode == null) break;
-                    trustedNode = trustedNode.trim();
-                    if (trustedNode.isEmpty()) break;
-
-                    int port;
-                    if (trustedNode.matches("^(?![0-9a-fA-F]*:[0-9a-fA-F]*:).*(:[0-9]+)$")) {
-                        int index = trustedNode.lastIndexOf(':');
-                        String portString = trustedNode.substring(index + 1);
-                        trustedNode = trustedNode.substring(0, index);
-                        try {
-                            port = Integer.parseInt(portString);
-                        } catch (NumberFormatException e) {
-                            LOG.error("Invalid port " + portString);
-                            // TODO: show error as notification
-                            return;
-                        }
-                    } else {
-                        port = 8444;
-                    }
-                    long timeoutInSeconds = preferences.getInt("sync_timeout", 120);
-                    try {
-                        LOG.info("Synchronization started");
-                        bmc.synchronize(InetAddress.getByName(trustedNode), port, timeoutInSeconds, true);
-                        LOG.info("Synchronization finished");
-                    } catch (UnknownHostException e) {
-                        LOG.error("Couldn't synchronize", e);
-                        // TODO: show error as notification
-                    }
-                    break;
-                }
                 case MSG_SEND_MESSAGE: {
                     Serializable identity = msg.getData().getSerializable(DATA_FIELD_IDENTITY);
                     Serializable address = msg.getData().getSerializable(DATA_FIELD_ADDRESS);
@@ -182,17 +144,17 @@ public class BitmessageService extends Service {
                 case MSG_START_NODE:
                     // TODO: warn user, option to restrict to WiFi
                     // (I'm not quite sure this can be done here, though)
-                    startService(new Intent(BitmessageService.this, BitmessageService.class));
+                    service.get().startService(new Intent(service.get(), BitmessageService.class));
                     running = true;
-                    startForeground(ONGOING_NOTIFICATION_ID, notification.getNotification());
+                    service.get().startForeground(ONGOING_NOTIFICATION_ID, notification.getNotification());
                     bmc.startup();
                     notification.show();
                     break;
                 case MSG_STOP_NODE:
                     bmc.shutdown();
                     running = false;
-                    stopForeground(false);
+                    service.get().stopForeground(false);
-                    stopService(new Intent(BitmessageService.this, BitmessageService.class));
+                    service.get().stopSelf();
                     break;
                 default:
                     super.handleMessage(msg);

app/src/main/java/ch/dissem/apps/abit/service/ProofOfWorkService.java

@@ -0,0 +1,88 @@
+package ch.dissem.apps.abit.service;
+
+import android.app.Service;
+import android.content.Intent;
+import android.os.Binder;
+import android.os.IBinder;
+import android.support.annotation.Nullable;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.lang.ref.WeakReference;
+
+import ch.dissem.apps.abit.notification.ProofOfWorkNotification;
+import ch.dissem.bitmessage.ports.MultiThreadedPOWEngine;
+import ch.dissem.bitmessage.ports.ProofOfWorkEngine;
+
+import static ch.dissem.apps.abit.notification.ProofOfWorkNotification.ONGOING_NOTIFICATION_ID;
+
+/**
+ * The Proof of Work Service makes sure POW is done in a foreground process, so it shouldn't be
+ * killed by the system before the nonce is found.
+ */
+public class ProofOfWorkService extends Service {
+    public static final Logger LOG = LoggerFactory.getLogger(ProofOfWorkService.class);
+
+    // Object to use as a thread-safe lock
+    private static final Object lock = new Object();
+    private static ProofOfWorkEngine engine;
+
+    @Override
+    public void onCreate() {
+        synchronized (lock) {
+            if (engine == null) {
+                engine = new MultiThreadedPOWEngine();
+            }
+        }
+    }
+
+    @Nullable
+    @Override
+    public IBinder onBind(Intent intent) {
+        return new PowBinder(engine, this);
+    }
+
+    public static class PowBinder extends Binder {
+        private final ProofOfWorkEngine engine;
+
+        private PowBinder(ProofOfWorkEngine engine, ProofOfWorkService service) {
+            this.engine = new EngineWrapper(engine, service);
+        }
+
+        public ProofOfWorkEngine getEngine() {
+            return engine;
+        }
+    }
+
+    private static class EngineWrapper implements ProofOfWorkEngine {
+        private final ProofOfWorkNotification notification;
+        private final ProofOfWorkEngine engine;
+        private final WeakReference<ProofOfWorkService> serviceRef;
+
+        private EngineWrapper(ProofOfWorkEngine engine, ProofOfWorkService service) {
+            this.engine = engine;
+            this.serviceRef = new WeakReference<>(service);
+            this.notification = new ProofOfWorkNotification(service);
+        }
+
+        @Override
+        public void calculateNonce(byte[] initialHash, byte[] target, final Callback callback) {
+            final ProofOfWorkService service = serviceRef.get();
+            service.startService(new Intent(service, ProofOfWorkService.class));
+            service.startForeground(ONGOING_NOTIFICATION_ID, notification.getNotification());
+            engine.calculateNonce(initialHash, target, new ProofOfWorkEngine.Callback() {
+                @Override
+                public void onNonceCalculated(byte[] nonce) {
+                    try {
+                        callback.onNonceCalculated(nonce);
+                    } finally {
+                        service.stopForeground(true);
+                        service.stopSelf();
+                    }
+                }
+            });
+
+        }
+    }
+}

app/src/main/java/ch/dissem/apps/abit/service/ServicePowEngine.java

@@ -0,0 +1,61 @@
+package ch.dissem.apps.abit.service;
+
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.ServiceConnection;
+import android.os.IBinder;
+
+import java.util.concurrent.Semaphore;
+
+import ch.dissem.apps.abit.service.ProofOfWorkService.PowBinder;
+import ch.dissem.bitmessage.ports.ProofOfWorkEngine;
+
+import static android.content.Context.BIND_AUTO_CREATE;
+
+/**
+ * Proof of Work engine that uses the Proof of Work service.
+ */
+public class ServicePowEngine implements ProofOfWorkEngine, ProofOfWorkEngine.Callback {
+    private final Semaphore semaphore = new Semaphore(1, true);
+    private final Context ctx;
+
+    private byte[] initialHash, targetValue;
+    private Callback callback;
+
+    public ServicePowEngine(Context ctx) {
+        this.ctx = ctx;
+    }
+
+    private ServiceConnection connection = new ServiceConnection() {
+        @Override
+        public void onServiceConnected(ComponentName name, IBinder service) {
+            ((PowBinder) service).getEngine().calculateNonce(initialHash, targetValue, ServicePowEngine.this);
+        }
+
+        @Override
+        public void onServiceDisconnected(ComponentName name) {
+            semaphore.release();
+        }
+    };
+
+    @Override
+    public void calculateNonce(byte[] initialHash, byte[] targetValue, Callback callback) {
+        try {
+            semaphore.acquire();
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+        }
+        this.initialHash = initialHash;
+        this.targetValue = targetValue;
+        this.callback = callback;
+        ctx.bindService(new Intent(ctx, ProofOfWorkService.class), connection, BIND_AUTO_CREATE);
+    }
+
+    @Override
+    public void onNonceCalculated(byte[] bytes) {
+        callback.onNonceCalculated(bytes);
+        ctx.unbindService(connection);
+    }
+
+}

app/src/main/java/ch/dissem/apps/abit/service/Singleton.java

@@ -2,9 +2,6 @@ package ch.dissem.apps.abit.service;
 
 import android.content.Context;
 
-import java.util.Objects;
-
-import ch.dissem.apps.abit.MessageListActivity;
 import ch.dissem.apps.abit.listener.MessageListener;
 import ch.dissem.apps.abit.repository.AndroidAddressRepository;
 import ch.dissem.apps.abit.repository.AndroidInventory;
@@ -15,7 +12,6 @@ import ch.dissem.bitmessage.networking.DefaultNetworkHandler;
 import ch.dissem.bitmessage.ports.AddressRepository;
 import ch.dissem.bitmessage.ports.MemoryNodeRegistry;
 import ch.dissem.bitmessage.ports.MessageRepository;
-import ch.dissem.bitmessage.ports.Security;
 import ch.dissem.bitmessage.security.sc.SpongySecurity;
 
 /**
@@ -33,6 +29,7 @@ public class Singleton {
                     final Context ctx = context.getApplicationContext();
                     SqlHelper sqlHelper = new SqlHelper(ctx);
                     bitmessageContext = new BitmessageContext.Builder()
+                            .proofOfWorkEngine(new ServicePowEngine(ctx))
                             .security(new SpongySecurity())
                             .nodeRegistry(new MemoryNodeRegistry())
                             .inventory(new AndroidInventory(sqlHelper))

app/src/main/java/ch/dissem/apps/abit/synchronization/SyncAdapter.java

@@ -15,6 +15,8 @@ import org.slf4j.LoggerFactory;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
 
+import ch.dissem.apps.abit.R;
+import ch.dissem.apps.abit.notification.ErrorNotification;
 import ch.dissem.apps.abit.service.Singleton;
 import ch.dissem.bitmessage.BitmessageContext;
 
@@ -59,8 +61,9 @@ public class SyncAdapter extends AbstractThreadedSyncAdapter {
             try {
                 port = Integer.parseInt(portString);
             } catch (NumberFormatException e) {
-                LOG.error("Invalid port " + portString);
+                new ErrorNotification(getContext())
-                // TODO: show error as notification
+                        .setError(R.string.error_invalid_sync_port, portString)
+                        .show();
                 return;
             }
         } else {
@@ -72,8 +75,11 @@ public class SyncAdapter extends AbstractThreadedSyncAdapter {
             bmc.synchronize(InetAddress.getByName(trustedNode), port, timeoutInSeconds, true);
             LOG.info("Synchronization finished");
         } catch (UnknownHostException e) {
-            LOG.error("Couldn't synchronize", e);
+            new ErrorNotification(getContext())
-            // TODO: show error as notification
+                    .setError(R.string.error_invalid_sync_host)
+                    .show();
+        } catch (RuntimeException e) {
+            LOG.error(e.getMessage(), e);
         }
     }
 }

app/src/main/res/values-de/strings.xml

@@ -42,4 +42,8 @@
     <string name="connection_info_n">Stream %1$d: %2$d Verbindungen</string>
     <string name="connection_info_disconnected">Getrennt</string>
     <string name="connection_info_pending">Verbindung wird aufgebaut…</string>
+    <string name="proof_of_work_text">Warnung: dies könnte das Gerät erwärmen bis die Batterie leer ist.</string>
+    <string name="proof_of_work_title">Proof of Work</string>
+    <string name="error_invalid_sync_host">Synchronisation fehlgeschlagen: der vertrauenswürdige Knoten konnte nicht erreicht werden.</string>
+    <string name="error_invalid_sync_port">Ungültiger Port in den Synchronisationseinstellungen: %s</string>
 </resources>

app/src/main/res/values/strings.xml

@@ -42,4 +42,8 @@
     <string name="send">Send</string>
     <string name="connection_info_disconnected">Disconnected</string>
     <string name="connection_info_pending">Connecting…</string>
+    <string name="proof_of_work_title">Proof of Work</string>
+    <string name="proof_of_work_text">Warning: This might heat your device until the battery\'s dead.</string>
+    <string name="error_invalid_sync_port">Invalid port in synchronization settings: %s</string>
+    <string name="error_invalid_sync_host">Synchronization failed: Trusted node could not be reached.</string>
 </resources>