Merge pull request #3970 from ByteHamster/extract-gpodder

SyncService refactoring

app/build.gradle

@@ -143,6 +143,7 @@ dependencies {
     implementation "androidx.recyclerview:recyclerview:1.0.0"
     implementation "androidx.coordinatorlayout:coordinatorlayout:1.1.0"
     implementation "androidx.media:media:1.1.0"
+    implementation "android.arch.work:work-runtime:$workManagerVersion"
     implementation "com.google.android.material:material:1.0.0"
     annotationProcessor "androidx.annotation:annotation:1.1.0"
     compileOnly "com.google.android.wearable:wearable:$wearableSupportVersion"

app/src/androidTest/java/de/test/antennapod/gpodnet/GPodnetServiceTest.java

@@ -5,10 +5,11 @@ import java.util.Arrays;
 import java.util.List;
 
 import androidx.test.runner.AndroidJUnit4;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.service.download.AntennapodHttpClient;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetDevice;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetTag;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetDevice;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetTag;
 import org.junit.Before;
 import org.junit.Ignore;
 import org.junit.Test;
@@ -30,7 +31,7 @@ public class GPodnetServiceTest {
 
     @Before
     public void setUp() {
-        service = new GpodnetService();
+        service = new GpodnetService(AntennapodHttpClient.getHttpClient(), GpodnetService.DEFAULT_BASE_HOST);
     }
 
     private void authenticate() throws GpodnetServiceException {
@@ -42,7 +43,7 @@ public class GPodnetServiceTest {
         authenticate();
         ArrayList<String> l = new ArrayList<>();
         l.add("http://bitsundso.de/feed");
-        service.uploadSubscriptions(USER, "radio", l);
+        service.uploadSubscriptions("radio", l);
     }
 
     @Test
@@ -51,7 +52,7 @@ public class GPodnetServiceTest {
         ArrayList<String> l = new ArrayList<>();
         l.add("http://bitsundso.de/feed");
         l.add("http://gamesundso.de/feed");
-        service.uploadSubscriptions(USER, "radio", l);
+        service.uploadSubscriptions("radio", l);
     }
 
     @Test
@@ -61,41 +62,40 @@ public class GPodnetServiceTest {
         List<String> subscriptions = Arrays.asList(URLS[0], URLS[1]);
         List<String> removed = singletonList(URLS[0]);
         List<String> added = Arrays.asList(URLS[2], URLS[3]);
-        service.uploadSubscriptions(USER, "radio", subscriptions);
+        service.uploadSubscriptions("radio", subscriptions);
-        service.uploadChanges(USER, "radio", added, removed);
+        service.uploadChanges("radio", added, removed);
     }
 
     @Test
     public void testGetSubscriptionChanges() throws GpodnetServiceException {
         authenticate();
-        service.getSubscriptionChanges(USER, "radio", 1362322610L);
+        service.getSubscriptionChanges("radio", 1362322610L);
     }
 
     @Test
     public void testGetSubscriptionsOfUser()
             throws GpodnetServiceException {
         authenticate();
-        service.getSubscriptionsOfUser(USER);
+        service.getSubscriptionsOfUser();
     }
 
     @Test
     public void testGetSubscriptionsOfDevice()
             throws GpodnetServiceException {
         authenticate();
-        service.getSubscriptionsOfDevice(USER, "radio");
+        service.getSubscriptionsOfDevice("radio");
     }
 
     @Test
     public void testConfigureDevices() throws GpodnetServiceException {
         authenticate();
-        service.configureDevice(USER, "foo", "This is an updated caption",
+        service.configureDevice("foo", "This is an updated caption",  GpodnetDevice.DeviceType.LAPTOP);
-                GpodnetDevice.DeviceType.LAPTOP);
     }
 
     @Test
     public void testGetDevices() throws GpodnetServiceException {
         authenticate();
-        service.getDevices(USER);
+        service.getDevices();
     }
 
     @Test

app/src/main/java/de/danoeh/antennapod/activity/gpoddernet/GpodnetAuthenticationActivity.java

@@ -30,12 +30,13 @@ import java.util.regex.Pattern;
 import de.danoeh.antennapod.BuildConfig;
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.activity.MainActivity;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetDevice;
 import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
-import de.danoeh.antennapod.core.service.GpodnetSyncService;
+import de.danoeh.antennapod.core.service.download.AntennapodHttpClient;
+import de.danoeh.antennapod.core.sync.SyncService;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetDevice;
 
 /**
  * Guides the user through the authentication process
@@ -69,7 +70,7 @@ public class GpodnetAuthenticationActivity extends AppCompatActivity {
         getSupportActionBar().setDisplayHomeAsUpEnabled(true);
 
         setContentView(R.layout.gpodnetauth_activity);
-        service = new GpodnetService();
+        service = new GpodnetService(AntennapodHttpClient.getHttpClient(), GpodnetPreferences.getHostname());
 
         viewFlipper = findViewById(R.id.viewflipper);
         LayoutInflater inflater = (LayoutInflater)
@@ -85,14 +86,6 @@ public class GpodnetAuthenticationActivity extends AppCompatActivity {
         advance();
     }
 
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        if (service != null) {
-            service.shutdown();
-        }
-    }
-
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()) {
@@ -221,7 +214,7 @@ public class GpodnetAuthenticationActivity extends AppCompatActivity {
             @Override
             protected List<GpodnetDevice> doInBackground(GpodnetService... params) {
                 try {
-                    return params[0].getDevices(username);
+                    return params[0].getDevices();
                 } catch (GpodnetServiceException e) {
                     e.printStackTrace();
                     return null;
@@ -268,7 +261,7 @@ public class GpodnetAuthenticationActivity extends AppCompatActivity {
                         @Override
                         protected GpodnetDevice doInBackground(GpodnetService... params) {
                             try {
-                                params[0].configureDevice(username, deviceStr, captionStr, GpodnetDevice.DeviceType.MOBILE);
+                                params[0].configureDevice(deviceStr, captionStr, GpodnetDevice.DeviceType.MOBILE);
                                 return new GpodnetDevice(deviceStr, captionStr, GpodnetDevice.DeviceType.MOBILE.toString(), 0);
                             } catch (GpodnetServiceException e) {
                                 e.printStackTrace();
@@ -349,8 +342,8 @@ public class GpodnetAuthenticationActivity extends AppCompatActivity {
         final Button back = view.findViewById(R.id.butGoMainscreen);
 
         sync.setOnClickListener(v -> {
-            GpodnetSyncService.sendSyncIntent(GpodnetAuthenticationActivity.this);
             finish();
+            SyncService.sync(getApplicationContext());
         });
         back.setOnClickListener(v -> {
             Intent intent = new Intent(GpodnetAuthenticationActivity.this, MainActivity.class);

app/src/main/java/de/danoeh/antennapod/adapter/gpodnet/PodcastListAdapter.java

@@ -13,13 +13,14 @@ import com.bumptech.glide.Glide;
 import com.bumptech.glide.load.resource.bitmap.FitCenter;
 import com.bumptech.glide.load.resource.bitmap.RoundedCorners;
 import com.bumptech.glide.request.RequestOptions;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
 import org.apache.commons.lang3.StringUtils;
 
-import java.util.List;
 
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.core.glide.ApGlideSettings;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
+
+import java.util.List;
 
 /**
  * Adapter for displaying a list of GPodnetPodcast-Objects.

app/src/main/java/de/danoeh/antennapod/adapter/gpodnet/TagListAdapter.java

@@ -7,10 +7,10 @@ import android.view.ViewGroup;
 import android.widget.ArrayAdapter;
 import android.widget.TextView;
 
-import java.util.List;
-
 import de.danoeh.antennapod.R;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetTag;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetTag;
+
+import java.util.List;
 
 /**
  * Adapter for displaying a list of GPodnetPodcast-Objects.

app/src/main/java/de/danoeh/antennapod/config/ClientConfigurator.java

@@ -14,7 +14,6 @@ class ClientConfigurator {
         ClientConfig.USER_AGENT = "AntennaPod/" + BuildConfig.VERSION_NAME;
         ClientConfig.applicationCallbacks = new ApplicationCallbacksImpl();
         ClientConfig.downloadServiceCallbacks = new DownloadServiceCallbacksImpl();
-        ClientConfig.gpodnetCallbacks = new GpodnetCallbacksImpl();
         ClientConfig.playbackServiceCallbacks = new PlaybackServiceCallbacksImpl();
         ClientConfig.dbTasksCallbacks = new DBTasksCallbacksImpl();
         ClientConfig.castCallbacks = new CastCallbackImpl();

app/src/main/java/de/danoeh/antennapod/config/GpodnetCallbacksImpl.java

@@ -1,22 +0,0 @@
-package de.danoeh.antennapod.config;
-
-import android.app.PendingIntent;
-import android.content.Context;
-import android.content.Intent;
-
-import de.danoeh.antennapod.activity.MainActivity;
-import de.danoeh.antennapod.core.GpodnetCallbacks;
-
-
-public class GpodnetCallbacksImpl implements GpodnetCallbacks {
-    @Override
-    public boolean gpodnetEnabled() {
-        return true;
-    }
-
-    @Override
-    public PendingIntent getGpodnetSyncServiceErrorNotificationPendingIntent(Context context) {
-        return PendingIntent.getActivity(context, 0, new Intent(context, MainActivity.class),
-                PendingIntent.FLAG_UPDATE_CURRENT);
-    }
-}

app/src/main/java/de/danoeh/antennapod/dialog/GpodnetSetHostnameDialog.java

@@ -10,8 +10,8 @@ import android.widget.EditText;
 import android.widget.LinearLayout;
 
 import de.danoeh.antennapod.R;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
 import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
 
 /**
  * Creates a dialog that lets the user change the hostname for the gpodder.net service.

app/src/main/java/de/danoeh/antennapod/discovery/GpodnetPodcastSearcher.java

@@ -1,8 +1,10 @@
 package de.danoeh.antennapod.discovery;
 
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.service.download.AntennapodHttpClient;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
 import io.reactivex.Single;
 import io.reactivex.SingleOnSubscribe;
 import io.reactivex.android.schedulers.AndroidSchedulers;
@@ -14,9 +16,9 @@ import java.util.List;
 public class GpodnetPodcastSearcher implements PodcastSearcher {
     public Single<List<PodcastSearchResult>> search(String query) {
         return Single.create((SingleOnSubscribe<List<PodcastSearchResult>>) subscriber -> {
-            GpodnetService service = null;
             try {
-                service = new GpodnetService();
+                GpodnetService service = new GpodnetService(AntennapodHttpClient.getHttpClient(),
+                        GpodnetPreferences.getHostname());
                 List<GpodnetPodcast> gpodnetPodcasts = service.searchPodcasts(query, 0);
                 List<PodcastSearchResult> results = new ArrayList<>();
                 for (GpodnetPodcast podcast : gpodnetPodcasts) {
@@ -26,10 +28,6 @@ public class GpodnetPodcastSearcher implements PodcastSearcher {
             } catch (GpodnetServiceException e) {
                 e.printStackTrace();
                 subscriber.onError(e);
-            } finally {
-                if (service != null) {
-                    service.shutdown();
-                }
             }
         })
         .subscribeOn(Schedulers.io())

app/src/main/java/de/danoeh/antennapod/discovery/PodcastSearchResult.java

@@ -1,7 +1,7 @@
 package de.danoeh.antennapod.discovery;
 
 import androidx.annotation.Nullable;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
 import de.mfietz.fyydlin.SearchHit;
 import org.json.JSONArray;
 import org.json.JSONException;

app/src/main/java/de/danoeh/antennapod/fragment/gpodnet/PodcastListFragment.java

@@ -27,10 +27,11 @@ import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.activity.MainActivity;
 import de.danoeh.antennapod.activity.OnlineFeedViewActivity;
 import de.danoeh.antennapod.adapter.gpodnet.PodcastListAdapter;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.service.download.AntennapodHttpClient;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
-import de.danoeh.antennapod.menuhandler.MenuItemUtils;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
 
 /**
  * Displays a list of GPodnetPodcast-Objects in a GridView
@@ -115,18 +116,14 @@ public abstract class PodcastListFragment extends Fragment {
 
             @Override
             protected List<GpodnetPodcast> doInBackground(Void... params) {
-                GpodnetService service = null;
                 try {
-                    service = new GpodnetService();
+                    GpodnetService service = new GpodnetService(AntennapodHttpClient.getHttpClient(),
+                            GpodnetPreferences.getHostname());
                     return loadPodcastData(service);
                 } catch (GpodnetServiceException e) {
                     exception = e;
                     e.printStackTrace();
                     return null;
-                } finally {
-                    if (service != null) {
-                        service.shutdown();
-                    }
                 }
             }
 

app/src/main/java/de/danoeh/antennapod/fragment/gpodnet/PodcastTopListFragment.java

@@ -1,16 +1,12 @@
 package de.danoeh.antennapod.fragment.gpodnet;
 
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
+
 import java.util.List;
 
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
-
-/**
- *
- */
 public class PodcastTopListFragment extends PodcastListFragment {
-    private static final String TAG = "PodcastTopListFragment";
     private static final int PODCAST_COUNT = 50;
 
     @Override

app/src/main/java/de/danoeh/antennapod/fragment/gpodnet/SearchListFragment.java

@@ -7,15 +7,14 @@ import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
 import org.apache.commons.lang3.Validate;
 
-import java.util.List;
-
 import de.danoeh.antennapod.R;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
+
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
+import java.util.List;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
-import de.danoeh.antennapod.menuhandler.MenuItemUtils;
 
 /**
  * Performs a search on the gpodder.net directory and displays the results.

app/src/main/java/de/danoeh/antennapod/fragment/gpodnet/SuggestionListFragment.java

@@ -3,10 +3,10 @@ package de.danoeh.antennapod.fragment.gpodnet;
 import java.util.Collections;
 import java.util.List;
 
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
 import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
 
 /**
  * Displays suggestions from gpodder.net

app/src/main/java/de/danoeh/antennapod/fragment/gpodnet/TagFragment.java

@@ -3,15 +3,15 @@ package de.danoeh.antennapod.fragment.gpodnet;
 import android.os.Bundle;
 import androidx.annotation.Nullable;
 
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetTag;
 import org.apache.commons.lang3.Validate;
 
-import java.util.List;
-
 import de.danoeh.antennapod.activity.MainActivity;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
+
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
+import java.util.List;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetTag;
 
 /**
  * Shows all podcasts from gpodder.net that belong to a specific tag.

app/src/main/java/de/danoeh/antennapod/fragment/gpodnet/TagListFragment.java

@@ -13,15 +13,16 @@ import android.view.MenuItem;
 import android.view.View;
 import android.widget.TextView;
 
-import java.util.List;
-
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.activity.MainActivity;
 import de.danoeh.antennapod.adapter.gpodnet.TagListAdapter;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.service.download.AntennapodHttpClient;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetTag;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
-import de.danoeh.antennapod.menuhandler.MenuItemUtils;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetServiceException;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetTag;
+
+import java.util.List;
 
 public class TagListFragment extends ListFragment {
     private static final int COUNT = 50;
@@ -91,15 +92,14 @@ public class TagListFragment extends ListFragment {
 
             @Override
             protected List<GpodnetTag> doInBackground(Void... params) {
-                GpodnetService service = new GpodnetService();
+                GpodnetService service = new GpodnetService(AntennapodHttpClient.getHttpClient(),
+                        GpodnetPreferences.getHostname());
                 try {
                     return service.getTopTags(COUNT);
                 } catch (GpodnetServiceException e) {
                     e.printStackTrace();
                     exception = e;
                     return null;
-                } finally {
-                    service.shutdown();
                 }
             }
 

app/src/main/java/de/danoeh/antennapod/fragment/preferences/GpodderPreferencesFragment.java

@@ -10,10 +10,15 @@ import android.text.format.DateUtils;
 import android.widget.Toast;
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.activity.PreferenceActivity;
+import de.danoeh.antennapod.core.event.SyncServiceEvent;
 import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
-import de.danoeh.antennapod.core.service.GpodnetSyncService;
+import de.danoeh.antennapod.core.sync.SyncService;
 import de.danoeh.antennapod.dialog.AuthenticationDialog;
 import de.danoeh.antennapod.dialog.GpodnetSetHostnameDialog;
+import org.greenrobot.eventbus.EventBus;
+import org.greenrobot.eventbus.Subscribe;
+import org.greenrobot.eventbus.ThreadMode;
+
 
 public class GpodderPreferencesFragment extends PreferenceFragmentCompat {
     private static final String PREF_GPODNET_LOGIN = "pref_gpodnet_authenticate";
@@ -34,28 +39,30 @@ public class GpodderPreferencesFragment extends PreferenceFragmentCompat {
     public void onStart() {
         super.onStart();
         ((PreferenceActivity) getActivity()).getSupportActionBar().setTitle(R.string.gpodnet_main_label);
-    }
-
-    @Override
-    public void onResume() {
-        super.onResume();
-        GpodnetPreferences.registerOnSharedPreferenceChangeListener(gpoddernetListener);
         updateGpodnetPreferenceScreen();
+        EventBus.getDefault().register(this);
     }
 
     @Override
-    public void onPause() {
+    public void onStop() {
-        super.onPause();
+        super.onStop();
-        GpodnetPreferences.unregisterOnSharedPreferenceChangeListener(gpoddernetListener);
+        EventBus.getDefault().unregister(this);
+        ((PreferenceActivity) getActivity()).getSupportActionBar().setSubtitle("");
     }
 
-    private final SharedPreferences.OnSharedPreferenceChangeListener gpoddernetListener =
+    @Subscribe(threadMode = ThreadMode.MAIN, sticky = true)
-            (sharedPreferences, key) -> {
+    public void syncStatusChanged(SyncServiceEvent event) {
-                if (GpodnetPreferences.PREF_LAST_SYNC_ATTEMPT_TIMESTAMP.equals(key)) {
+        if (!GpodnetPreferences.loggedIn()) {
-                    updateLastGpodnetSyncReport(GpodnetPreferences.getLastSyncAttemptResult(),
+            return;
-                            GpodnetPreferences.getLastSyncAttemptTimestamp());
+        }
-                }
+        if (event.getMessageResId() == R.string.sync_status_error
-            };
+                || event.getMessageResId() == R.string.sync_status_success) {
+            updateLastGpodnetSyncReport(SyncService.isLastSyncSuccessful(getContext()),
+                    SyncService.getLastSyncAttempt(getContext()));
+        } else {
+            ((PreferenceActivity) getActivity()).getSupportActionBar().setSubtitle(event.getMessageResId());
+        }
+    }
 
     private void setupGpodderScreen() {
         final Activity activity = getActivity();
@@ -75,35 +82,25 @@ public class GpodderPreferencesFragment extends PreferenceFragmentCompat {
                     return true;
                 });
         findPreference(PREF_GPODNET_SYNC).setOnPreferenceClickListener(preference -> {
-                    GpodnetSyncService.sendSyncIntent(getActivity().getApplicationContext());
+            SyncService.syncImmediately(getActivity().getApplicationContext());
-                    Toast toast = Toast.makeText(getActivity(), R.string.pref_gpodnet_sync_started,
+            return true;
-                            Toast.LENGTH_SHORT);
+        });
-                    toast.show();
-                    return true;
-                });
         findPreference(PREF_GPODNET_FORCE_FULL_SYNC).setOnPreferenceClickListener(preference -> {
-                    GpodnetPreferences.setLastSubscriptionSyncTimestamp(0L);
+            SyncService.fullSync(getContext());
-                    GpodnetPreferences.setLastEpisodeActionsSyncTimestamp(0L);
+            return true;
-                    GpodnetPreferences.setLastSyncAttempt(false, 0);
+        });
-                    updateLastGpodnetSyncReport(false, 0);
-                    GpodnetSyncService.sendSyncIntent(getActivity().getApplicationContext());
-                    Toast toast = Toast.makeText(getActivity(), R.string.pref_gpodnet_sync_started,
-                            Toast.LENGTH_SHORT);
-                    toast.show();
-                    return true;
-                });
         findPreference(PREF_GPODNET_LOGOUT).setOnPreferenceClickListener(preference -> {
-                    GpodnetPreferences.logout();
+            GpodnetPreferences.logout();
-                    Toast toast = Toast.makeText(activity, R.string.pref_gpodnet_logout_toast, Toast.LENGTH_SHORT);
+            Toast toast = Toast.makeText(activity, R.string.pref_gpodnet_logout_toast, Toast.LENGTH_SHORT);
-                    toast.show();
+            toast.show();
-                    updateGpodnetPreferenceScreen();
+            updateGpodnetPreferenceScreen();
-                    return true;
+            return true;
-                });
+        });
         findPreference(PREF_GPODNET_HOSTNAME).setOnPreferenceClickListener(preference -> {
-                    GpodnetSetHostnameDialog.createDialog(activity).setOnDismissListener(
+            GpodnetSetHostnameDialog.createDialog(activity).setOnDismissListener(
-                            dialog -> updateGpodnetPreferenceScreen());
+                    dialog -> updateGpodnetPreferenceScreen());
-                    return true;
+            return true;
-                });
+        });
     }
 
     private void updateGpodnetPreferenceScreen() {
@@ -114,35 +111,24 @@ public class GpodderPreferencesFragment extends PreferenceFragmentCompat {
         findPreference(PREF_GPODNET_FORCE_FULL_SYNC).setEnabled(loggedIn);
         findPreference(PREF_GPODNET_LOGOUT).setEnabled(loggedIn);
         findPreference(PREF_GPODNET_NOTIFICATIONS).setEnabled(loggedIn);
-        if(loggedIn) {
+        if (loggedIn) {
             String format = getActivity().getString(R.string.pref_gpodnet_login_status);
             String summary = String.format(format, GpodnetPreferences.getUsername(),
                     GpodnetPreferences.getDeviceID());
             findPreference(PREF_GPODNET_LOGOUT).setSummary(Html.fromHtml(summary));
-            updateLastGpodnetSyncReport(GpodnetPreferences.getLastSyncAttemptResult(),
+            updateLastGpodnetSyncReport(SyncService.isLastSyncSuccessful(getContext()),
-                    GpodnetPreferences.getLastSyncAttemptTimestamp());
+                    SyncService.getLastSyncAttempt(getContext()));
         } else {
             findPreference(PREF_GPODNET_LOGOUT).setSummary(null);
-            updateLastGpodnetSyncReport(false, 0);
         }
         findPreference(PREF_GPODNET_HOSTNAME).setSummary(GpodnetPreferences.getHostname());
     }
 
     private void updateLastGpodnetSyncReport(boolean successful, long lastTime) {
-        Preference sync = findPreference(PREF_GPODNET_SYNC);
+        String status = String.format("%1$s (%2$s)", getString(successful
-        if (lastTime != 0) {
+                        ? R.string.gpodnetsync_pref_report_successful : R.string.gpodnetsync_pref_report_failed),
-            sync.setSummary(getActivity().getString(R.string.pref_gpodnet_sync_changes_sum) + "\n" +
+                        DateUtils.getRelativeDateTimeString(getContext(),
-                    getActivity().getString(R.string.pref_gpodnet_sync_sum_last_sync_line,
+                        lastTime, DateUtils.MINUTE_IN_MILLIS, DateUtils.WEEK_IN_MILLIS, DateUtils.FORMAT_SHOW_TIME));
-                            getActivity().getString(successful ?
+        ((PreferenceActivity) getActivity()).getSupportActionBar().setSubtitle(status);
-                                    R.string.gpodnetsync_pref_report_successful :
-                                    R.string.gpodnetsync_pref_report_failed),
-                            DateUtils.getRelativeDateTimeString(getActivity(),
-                                    lastTime,
-                                    DateUtils.MINUTE_IN_MILLIS,
-                                    DateUtils.WEEK_IN_MILLIS,
-                                    DateUtils.FORMAT_SHOW_TIME)));
-        } else {
-            sync.setSummary(getActivity().getString(R.string.pref_gpodnet_sync_changes_sum));
-        }
     }
 }

app/src/main/java/de/danoeh/antennapod/menuhandler/FeedItemMenuHandler.java

@@ -12,13 +12,13 @@ import android.view.MenuItem;
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.FeedMedia;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeAction;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeAction.Action;
 import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
 import de.danoeh.antennapod.core.preferences.PlaybackPreferences;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
 import de.danoeh.antennapod.core.service.playback.PlaybackService;
 import de.danoeh.antennapod.core.storage.DBWriter;
+import de.danoeh.antennapod.core.sync.SyncService;
+import de.danoeh.antennapod.core.sync.model.EpisodeAction;
 import de.danoeh.antennapod.core.util.FeedItemUtil;
 import de.danoeh.antennapod.core.util.IntentUtils;
 import de.danoeh.antennapod.core.util.ShareUtils;
@@ -191,14 +191,13 @@ public class FeedItemMenuHandler {
                     FeedMedia media = selectedItem.getMedia();
                     // not all items have media, Gpodder only cares about those that do
                     if (media != null) {
-                        GpodnetEpisodeAction actionPlay = new GpodnetEpisodeAction.Builder(selectedItem, Action.PLAY)
+                        EpisodeAction actionPlay = new EpisodeAction.Builder(selectedItem, EpisodeAction.PLAY)
-                                .currentDeviceId()
                                 .currentTimestamp()
                                 .started(media.getDuration() / 1000)
                                 .position(media.getDuration() / 1000)
                                 .total(media.getDuration() / 1000)
                                 .build();
-                        GpodnetPreferences.enqueueEpisodeAction(actionPlay);
+                        SyncService.enqueueEpisodeAction(context, actionPlay);
                     }
                 }
                 break;
@@ -206,11 +205,10 @@ public class FeedItemMenuHandler {
                 selectedItem.setPlayed(false);
                 DBWriter.markItemPlayed(selectedItem, FeedItem.UNPLAYED, false);
                 if (GpodnetPreferences.loggedIn() && selectedItem.getMedia() != null) {
-                    GpodnetEpisodeAction actionNew = new GpodnetEpisodeAction.Builder(selectedItem, Action.NEW)
+                    EpisodeAction actionNew = new EpisodeAction.Builder(selectedItem, EpisodeAction.NEW)
-                            .currentDeviceId()
                             .currentTimestamp()
                             .build();
-                    GpodnetPreferences.enqueueEpisodeAction(actionNew);
+                    SyncService.enqueueEpisodeAction(context, actionNew);
                 }
                 break;
             case R.id.add_to_queue_item:

app/src/main/res/layout/gpodnetauth_credentials.xml

@@ -1,28 +1,25 @@
 <?xml version="1.0" encoding="utf-8"?>
-
+<RelativeLayout
-<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:android="http://schemas.android.com/apk/res/android"
-                xmlns:tools="http://schemas.android.com/tools"
+        xmlns:tools="http://schemas.android.com/tools"
-                android:layout_width="match_parent"
-                android:layout_height="match_parent">
-
-    <TextView
-        android:id="@id/txtvTitle"
         android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:padding="16dp">
+
+    <ImageView
+        android:id="@id/icon"
+        android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:text="@string/gpodnetauth_login_title"
+        android:src="@drawable/gpodder_icon" />
-        android:layout_alignParentTop="true"
-        android:layout_margin="16dp"
-        style="@style/AntennaPod.TextView.Heading"/>
 
     <TextView
         android:id="@id/txtvDescription"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="@string/gpodnetauth_login_descr"
-        android:layout_below="@id/txtvTitle"
+        android:layout_below="@id/icon"
         android:textSize="@dimen/text_size_medium"
-        android:textColor="?android:attr/textColorSecondary"
+        android:textColor="?android:attr/textColorPrimary"/>
-        android:layout_margin="16dp"/>
 
     <EditText
         android:id="@+id/etxtUsername"
@@ -30,7 +27,6 @@
         android:layout_height="wrap_content"
         android:hint="@string/username_label"
         android:layout_below="@id/txtvDescription"
-        android:layout_margin="8dp"
         android:focusable="true"
         android:focusableInTouchMode="true"
         android:cursorVisible="true"
@@ -46,7 +42,6 @@
         android:hint="@string/password_label"
         android:layout_below="@id/etxtUsername"
         android:inputType="textPassword"
-        android:layout_margin="8dp"
         android:focusable="true"
         android:focusableInTouchMode="true"
         android:cursorVisible="true"
@@ -60,8 +55,7 @@
         android:layout_below="@id/etxtPassword"
         android:layout_alignParentRight="true"
         android:layout_alignParentEnd="true"
-        android:text="@string/gpodnetauth_login_butLabel"
+        android:text="@string/gpodnetauth_login_butLabel"/>
-        android:layout_margin="8dp"/>
 
     <TextView
         android:id="@+id/txtvError"
@@ -94,8 +88,8 @@
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:textSize="@dimen/text_size_medium"
-        android:textColor="?android:attr/textColorSecondary"
+        android:textColor="?android:attr/textColorPrimary"
-        android:layout_margin="16dp"
+        android:layout_marginTop="16dp"
         android:text="@string/gpodnetauth_login_register"
         android:autoLink="web"
         android:layout_below="@id/butLogin"/>

app/src/main/res/layout/gpodnetauth_device.xml

@@ -1,9 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
-
+<RelativeLayout
-<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:android="http://schemas.android.com/apk/res/android"
-                xmlns:tools="http://schemas.android.com/tools"
+        xmlns:tools="http://schemas.android.com/tools"
-                android:layout_width="match_parent"
+        android:layout_width="match_parent"
-                android:layout_height="match_parent">
+        android:layout_height="match_parent"
+        android:padding="16dp">
 
     <TextView
         android:id="@+id/txtvTitle"
@@ -11,7 +12,7 @@
         android:layout_height="wrap_content"
         android:text="@string/gpodnetauth_device_title"
         android:layout_alignParentTop="true"
-        android:layout_margin="16dp"
+        android:layout_marginBottom="16dp"
         style="@style/AntennaPod.TextView.Heading"/>
 
     <TextView
@@ -21,8 +22,7 @@
         android:text="@string/gpodnetauth_device_descr"
         android:layout_below="@id/txtvTitle"
         android:textSize="@dimen/text_size_medium"
-        android:textColor="?android:attr/textColorSecondary"
+        android:textColor="?android:attr/textColorPrimary"/>
-        android:layout_margin="16dp"/>
 
     <EditText
         android:id="@+id/etxtCaption"
@@ -30,7 +30,6 @@
         android:layout_height="wrap_content"
         android:hint="@string/gpodnetauth_device_caption"
         android:layout_below="@id/txtvDescription"
-        android:layout_margin="8dp"
         android:imeOptions="flagNoFullscreen"/>
 
     <TextView
@@ -39,29 +38,21 @@
         android:layout_height="wrap_content"
         android:text="@string/gpodnetauth_device_deviceID"
         android:textSize="@dimen/text_size_medium"
-        android:textColor="?android:attr/textColorSecondary"
+        android:layout_below="@id/etxtCaption"/>
-        android:layout_margin="8dp"
-        android:layout_alignTop="@+id/etxtDeviceID"
-        android:layout_alignLeft="@+id/etxtCaption"
-        android:layout_alignStart="@+id/etxtCaption"/>
 
     <EditText
         android:id="@+id/etxtDeviceID"
-        android:layout_width="0dp"
+        android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:layout_below="@id/etxtCaption"
+        android:layout_below="@id/txtvDeviceID"
-        android:layout_toRightOf="@id/txtvDeviceID"
-        android:layout_toEndOf="@id/txtvDeviceID"
         android:layout_alignParentRight="true"
         android:layout_alignParentEnd="true"
-        android:layout_margin="8dp"
         android:imeOptions="flagNoFullscreen"/>
 
     <Button
         android:id="@+id/butCreateNewDevice"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_margin="8dp"
         android:layout_alignParentRight="true"
         android:layout_alignParentEnd="true"
         android:layout_below="@id/etxtDeviceID"
@@ -77,7 +68,6 @@
         android:layout_toLeftOf="@id/butCreateNewDevice"
         android:layout_toStartOf="@id/butCreateNewDevice"
         android:textColor="@color/download_failed_red"
-        android:layout_margin="16dp"
         android:textSize="@dimen/text_size_small"
         tools:text="Error message"
         tools:background="@android:color/holo_green_dark" />
@@ -100,30 +90,25 @@
         android:layout_height="wrap_content"
         android:text="@string/gpodnetauth_device_chooseExistingDevice"
         android:layout_below="@id/butCreateNewDevice"
+        android:textColor="?android:attr/textColorPrimary"
         android:textSize="@dimen/text_size_medium"
-        android:textColor="?android:attr/textColorSecondary"
+        android:layout_marginTop="32dp"/>
-        android:layout_margin="16dp"/>
 
     <Button
         android:id="@+id/butChooseExistingDevice"
-        android:layout_width="0dp"
+        android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="@string/gpodnetauth_device_butChoose"
         android:layout_below="@+id/spinnerChooseDevice"
-        android:layout_alignLeft="@+id/butCreateNewDevice"
-        android:layout_alignStart="@+id/butCreateNewDevice"
-        android:layout_alignRight="@+id/butCreateNewDevice"
-        android:layout_alignEnd="@+id/butCreateNewDevice"/>
-
-    <Spinner
-        android:id="@+id/spinnerChooseDevice"
-        android:layout_width="0dp"
-        android:layout_height="wrap_content"
-        android:layout_below="@id/txtvChooseExistingDevice"
-        android:layout_alignParentLeft="true"
-        android:layout_alignParentStart="true"
-        android:layout_margin="8dp"
         android:layout_alignParentRight="true"
         android:layout_alignParentEnd="true"/>
 
+    <Spinner
+        android:id="@+id/spinnerChooseDevice"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_below="@id/txtvChooseExistingDevice"
+        android:layout_alignParentLeft="true"
+        android:layout_alignParentStart="true"/>
+
 </RelativeLayout>

app/src/main/res/layout/gpodnetauth_finish.xml

@@ -1,16 +1,22 @@
 <?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:padding="16dp">
 
-<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    <ImageView
-                android:layout_width="match_parent"
+        android:id="@id/icon"
-                android:layout_height="match_parent">
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:src="@drawable/gpodder_icon" />
 
     <TextView
         android:id="@+id/txtvTitle"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
+        android:layout_below="@id/icon"
         android:text="@string/gpodnetauth_finish_title"
-        android:layout_alignParentTop="true"
-        android:layout_margin="16dp"
         style="@style/AntennaPod.TextView.Heading"/>
 
     <TextView
@@ -20,15 +26,14 @@
         android:text="@string/gpodnetauth_finish_descr"
         android:layout_below="@id/txtvTitle"
         android:textSize="@dimen/text_size_medium"
-        android:textColor="?android:attr/textColorSecondary"
+        android:textColor="?android:attr/textColorPrimary" />
-        android:layout_margin="16dp"/>
 
     <Button
         android:id="@+id/butSyncNow"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_below="@id/txtvDescription"
-        android:layout_margin="16dp"
+        android:layout_marginTop="16dp"
         android:text="@string/gpodnetauth_finish_butsyncnow"/>
 
     <Button
@@ -36,7 +41,6 @@
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_below="@id/butSyncNow"
-        android:layout_margin="16dp"
         android:text="@string/gpodnetauth_finish_butgomainscreen"/>
 
 </RelativeLayout>

app/src/main/res/xml/preferences_integrations.xml

@@ -1,10 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <PreferenceScreen
-        xmlns:android="http://schemas.android.com/apk/res/android">
+        xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto">
 
     <Preference
             android:key="prefGpodderSettings"
             android:title="@string/gpodnet_main_label"
+            app:icon="@drawable/gpodder_icon"
             android:summary="@string/gpodnet_summary" />
 
 </PreferenceScreen>

config/checkstyle/checkstyle-new-code.xml

@@ -176,7 +176,6 @@
             <property name="ignoreFinal" value="false"/>
             <property name="allowedAbbreviationLength" value="1"/>
         </module>
-        <module name="OverloadMethodsDeclarationOrder"/>
         <module name="VariableDeclarationUsageDistance"/>
         <module name="MethodParamPad"/>
         <module name="WhitespaceAfter"/>

core/src/free/java/de/danoeh/antennapod/core/ClientConfig.java

@@ -30,8 +30,6 @@ public class ClientConfig {
 
     public static PlaybackServiceCallbacks playbackServiceCallbacks;
 
-    public static GpodnetCallbacks gpodnetCallbacks;
-
     public static DBTasksCallbacks dbTasksCallbacks;
 
     public static CastCallbacks castCallbacks;

core/src/main/AndroidManifest.xml

@@ -25,10 +25,6 @@
                 <action android:name="android.media.browse.MediaBrowserService"/>
             </intent-filter>
         </service>
-        <service
-            android:name=".service.GpodnetSyncService"
-            android:permission="android.permission.BIND_JOB_SERVICE"
-            android:enabled="true" />
 
         <receiver
             android:name=".receiver.MediaButtonReceiver"

core/src/main/java/de/danoeh/antennapod/core/GpodnetCallbacks.java

@@ -1,27 +0,0 @@
-package de.danoeh.antennapod.core;
-
-import android.app.PendingIntent;
-import android.content.Context;
-
-/**
- * Callbacks related to the gpodder.net integration of the core module
- */
-public interface GpodnetCallbacks {
-
-
-    /**
-     * Returns if true if the gpodder.net integration should be activated,
-     * false otherwise.
-     */
-    boolean gpodnetEnabled();
-
-    /**
-     * Returns a PendingIntent for the error notification of the GpodnetSyncService.
-     * <p/>
-     * What the PendingIntent does may be implementation-specific.
-     *
-     * @return A PendingIntent for the notification or null if gpodder.net integration
-     * has been disabled (i.e. gpodnetEnabled() == false).
-     */
-    PendingIntent getGpodnetSyncServiceErrorNotificationPendingIntent(Context context);
-}

core/src/main/java/de/danoeh/antennapod/core/event/SyncServiceEvent.java

@@ -0,0 +1,13 @@
+package de.danoeh.antennapod.core.event;
+
+public class SyncServiceEvent {
+    private final int messageResId;
+
+    public SyncServiceEvent(int messageResId) {
+        this.messageResId = messageResId;
+    }
+
+    public int getMessageResId() {
+        return messageResId;
+    }
+}

core/src/main/java/de/danoeh/antennapod/core/feed/FeedMedia.java

@@ -15,7 +15,6 @@ import java.util.Date;
 import java.util.List;
 import java.util.concurrent.Callable;
 
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeAction;
 import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
 import de.danoeh.antennapod.core.preferences.PlaybackPreferences;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
@@ -25,6 +24,8 @@ import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.storage.PodDBAdapter;
 import de.danoeh.antennapod.core.util.ChapterUtils;
 import de.danoeh.antennapod.core.util.playback.Playable;
+import de.danoeh.antennapod.core.sync.SyncService;
+import de.danoeh.antennapod.core.sync.model.EpisodeAction;
 
 public class FeedMedia extends FeedFile implements Playable {
     private static final String TAG = "FeedMedia";
@@ -502,17 +503,14 @@ public class FeedMedia extends FeedFile implements Playable {
 
     private void postPlaybackTasks(Context context, boolean completed) {
         if (item != null) {
-            // gpodder play action
+            if (startPosition >= 0 && (completed || startPosition < position) && GpodnetPreferences.loggedIn()) {
-            if (startPosition >= 0 && (completed || startPosition < position) &&
+                EpisodeAction action = new EpisodeAction.Builder(item, EpisodeAction.PLAY)
-                    GpodnetPreferences.loggedIn()) {
-                GpodnetEpisodeAction action = new GpodnetEpisodeAction.Builder(item, GpodnetEpisodeAction.Action.PLAY)
-                        .currentDeviceId()
                         .currentTimestamp()
                         .started(startPosition / 1000)
                         .position((completed ? duration : position) / 1000)
                         .total(duration / 1000)
                         .build();
-                GpodnetPreferences.enqueueEpisodeAction(action);
+                SyncService.enqueueEpisodeAction(context, action);
             }
         }
     }

core/src/main/java/de/danoeh/antennapod/core/gpoddernet/GpodnetServiceAuthenticationException.java

@@ -1,21 +0,0 @@
-package de.danoeh.antennapod.core.gpoddernet;
-
-public class GpodnetServiceAuthenticationException extends GpodnetServiceException {
-    private static final long serialVersionUID = 1L;
-
-    public GpodnetServiceAuthenticationException() {
-        super();
-    }
-
-    public GpodnetServiceAuthenticationException(String message, Throwable cause) {
-        super(message, cause);
-    }
-
-    public GpodnetServiceAuthenticationException(String message) {
-        super(message);
-    }
-
-    public GpodnetServiceAuthenticationException(Throwable cause) {
-        super(cause);
-    }
-}

core/src/main/java/de/danoeh/antennapod/core/gpoddernet/GpodnetServiceException.java

@@ -1,20 +0,0 @@
-package de.danoeh.antennapod.core.gpoddernet;
-
-public class GpodnetServiceException extends Exception {
-    private static final long serialVersionUID = 1L;
-
-    GpodnetServiceException() {
-    }
-
-    GpodnetServiceException(String message) {
-        super(message);
-    }
-
-    public GpodnetServiceException(Throwable cause) {
-        super(cause);
-    }
-
-    GpodnetServiceException(String message, Throwable cause) {
-        super(message, cause);
-    }
-}

core/src/main/java/de/danoeh/antennapod/core/gpoddernet/model/GpodnetEpisodeActionGetResponse.java

@@ -1,34 +0,0 @@
-package de.danoeh.antennapod.core.gpoddernet.model;
-
-
-import androidx.annotation.NonNull;
-
-import java.util.List;
-
-public class GpodnetEpisodeActionGetResponse {
-
-    private final List<GpodnetEpisodeAction> episodeActions;
-    private final long timestamp;
-
-    public GpodnetEpisodeActionGetResponse(@NonNull List<GpodnetEpisodeAction> episodeActions,
-                                           long timestamp) {
-        this.episodeActions = episodeActions;
-        this.timestamp = timestamp;
-    }
-
-    public List<GpodnetEpisodeAction> getEpisodeActions() {
-        return this.episodeActions;
-    }
-
-    public long getTimestamp() {
-        return this.timestamp;
-    }
-
-    @Override
-    public String toString() {
-        return "GpodnetEpisodeActionGetResponse{" +
-                "episodeActions=" + episodeActions +
-                ", timestamp=" + timestamp +
-                '}';
-    }
-}

core/src/main/java/de/danoeh/antennapod/core/preferences/GpodnetPreferences.java

@@ -2,22 +2,11 @@ package de.danoeh.antennapod.core.preferences;
 
 import android.content.Context;
 import android.content.SharedPreferences;
-import android.text.TextUtils;
 import android.util.Log;
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
-import java.util.concurrent.locks.ReentrantLock;
-
 import de.danoeh.antennapod.core.BuildConfig;
 import de.danoeh.antennapod.core.ClientConfig;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.SyncService;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeAction;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
-import de.danoeh.antennapod.core.service.GpodnetSyncService;
 
 /**
  * Manages preferences for accessing gpodder.net service
@@ -34,66 +23,23 @@ public class GpodnetPreferences {
     private static final String PREF_GPODNET_DEVICEID = "de.danoeh.antennapod.preferences.gpoddernet.deviceID";
     private static final String PREF_GPODNET_HOSTNAME = "prefGpodnetHostname";
 
-
-    private static final String PREF_LAST_SUBSCRIPTION_SYNC_TIMESTAMP = "de.danoeh.antennapod.preferences.gpoddernet.last_sync_timestamp";
-    private static final String PREF_LAST_EPISODE_ACTIONS_SYNC_TIMESTAMP = "de.danoeh.antennapod.preferences.gpoddernet.last_episode_actions_sync_timestamp";
-    private static final String PREF_SYNC_ADDED = "de.danoeh.antennapod.preferences.gpoddernet.sync_added";
-    private static final String PREF_SYNC_REMOVED = "de.danoeh.antennapod.preferences.gpoddernet.sync_removed";
-    private static final String PREF_SYNC_EPISODE_ACTIONS = "de.danoeh.antennapod.preferences.gpoddernet.sync_queued_episode_actions";
-    public static final String PREF_LAST_SYNC_ATTEMPT_TIMESTAMP = "de.danoeh.antennapod.preferences.gpoddernet.last_sync_attempt_timestamp";
-    private static final String PREF_LAST_SYNC_ATTEMPT_RESULT = "de.danoeh.antennapod.preferences.gpoddernet.last_sync_attempt_result";
-
     private static String username;
     private static String password;
     private static String deviceID;
     private static String hostname;
 
-    private static final ReentrantLock feedListLock = new ReentrantLock();
-    private static Set<String> addedFeeds;
-    private static Set<String> removedFeeds;
-
-    private static List<GpodnetEpisodeAction> queuedEpisodeActions;
-
-    /**
-     * Last value returned by getSubscriptionChanges call. Will be used for all subsequent calls of getSubscriptionChanges.
-     */
-    private static long lastSubscriptionSyncTimestamp;
-
-    private static long lastEpisodeActionsSyncTimeStamp;
-
-    private static long lastSyncAttemptTimestamp;
-
-    private static boolean lastSyncAttemptResult;
-
     private static boolean preferencesLoaded = false;
 
     private static SharedPreferences getPreferences() {
         return ClientConfig.applicationCallbacks.getApplicationInstance().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
     }
 
-    public static void registerOnSharedPreferenceChangeListener(
-            SharedPreferences.OnSharedPreferenceChangeListener listener) {
-        getPreferences().registerOnSharedPreferenceChangeListener(listener);
-    }
-
-    public static void unregisterOnSharedPreferenceChangeListener(
-            SharedPreferences.OnSharedPreferenceChangeListener listener) {
-        getPreferences().unregisterOnSharedPreferenceChangeListener(listener);
-    }
-
     private static synchronized void ensurePreferencesLoaded() {
         if (!preferencesLoaded) {
             SharedPreferences prefs = getPreferences();
             username = prefs.getString(PREF_GPODNET_USERNAME, null);
             password = prefs.getString(PREF_GPODNET_PASSWORD, null);
             deviceID = prefs.getString(PREF_GPODNET_DEVICEID, null);
-            lastSubscriptionSyncTimestamp = prefs.getLong(PREF_LAST_SUBSCRIPTION_SYNC_TIMESTAMP, 0);
-            lastEpisodeActionsSyncTimeStamp = prefs.getLong(PREF_LAST_EPISODE_ACTIONS_SYNC_TIMESTAMP, 0);
-            lastSyncAttemptTimestamp = prefs.getLong(PREF_LAST_SYNC_ATTEMPT_TIMESTAMP, 0);
-            lastSyncAttemptResult = prefs.getBoolean(PREF_LAST_SYNC_ATTEMPT_RESULT, false);
-            addedFeeds = readListFromString(prefs.getString(PREF_SYNC_ADDED, ""));
-            removedFeeds = readListFromString(prefs.getString(PREF_SYNC_REMOVED, ""));
-            queuedEpisodeActions = readEpisodeActionsFromString(prefs.getString(PREF_SYNC_EPISODE_ACTIONS, ""));
             hostname = checkGpodnetHostname(prefs.getString(PREF_GPODNET_HOSTNAME, GpodnetService.DEFAULT_BASE_HOST));
 
             preferencesLoaded = true;
@@ -106,24 +52,6 @@ public class GpodnetPreferences {
         editor.apply();
     }
 
-    private static void writePreference(String key, long value) {
-        SharedPreferences.Editor editor = getPreferences().edit();
-        editor.putLong(key, value);
-        editor.apply();
-    }
-
-    private static void writePreference(String key, Collection<String> value) {
-        SharedPreferences.Editor editor = getPreferences().edit();
-        editor.putString(key, writeListToString(value));
-        editor.apply();
-    }
-
-    private static void writePreference(String key, boolean value) {
-        SharedPreferences.Editor editor = getPreferences().edit();
-        editor.putBoolean(key, value);
-        editor.apply();
-    }
-
     public static String getUsername() {
         ensurePreferencesLoaded();
         return username;
@@ -154,43 +82,6 @@ public class GpodnetPreferences {
         writePreference(PREF_GPODNET_DEVICEID, deviceID);
     }
 
-    public static long getLastSubscriptionSyncTimestamp() {
-        ensurePreferencesLoaded();
-        return lastSubscriptionSyncTimestamp;
-    }
-
-    public static void setLastSubscriptionSyncTimestamp(long timestamp) {
-        GpodnetPreferences.lastSubscriptionSyncTimestamp = timestamp;
-        writePreference(PREF_LAST_SUBSCRIPTION_SYNC_TIMESTAMP, timestamp);
-    }
-
-    public static long getLastEpisodeActionsSyncTimestamp() {
-        ensurePreferencesLoaded();
-        return lastEpisodeActionsSyncTimeStamp;
-    }
-
-    public static void setLastEpisodeActionsSyncTimestamp(long timestamp) {
-        GpodnetPreferences.lastEpisodeActionsSyncTimeStamp = timestamp;
-        writePreference(PREF_LAST_EPISODE_ACTIONS_SYNC_TIMESTAMP, timestamp);
-    }
-
-    public static long getLastSyncAttemptTimestamp() {
-        ensurePreferencesLoaded();
-        return lastSyncAttemptTimestamp;
-    }
-
-    public static boolean getLastSyncAttemptResult() {
-        ensurePreferencesLoaded();
-        return lastSyncAttemptResult;
-    }
-
-    public static void setLastSyncAttempt(boolean result, long timestamp) {
-        GpodnetPreferences.lastSyncAttemptResult = result;
-        GpodnetPreferences.lastSyncAttemptTimestamp = timestamp;
-        writePreference(PREF_LAST_SYNC_ATTEMPT_RESULT, result);
-        writePreference(PREF_LAST_SYNC_ATTEMPT_TIMESTAMP, timestamp);
-    }
-
     public static String getHostname() {
         ensurePreferencesLoaded();
         return hostname;
@@ -205,92 +96,6 @@ public class GpodnetPreferences {
         }
     }
 
-    public static void addAddedFeed(String feed) {
-        ensurePreferencesLoaded();
-        feedListLock.lock();
-        if (addedFeeds.add(feed)) {
-            writePreference(PREF_SYNC_ADDED, addedFeeds);
-        }
-        if (removedFeeds.remove(feed)) {
-            writePreference(PREF_SYNC_REMOVED, removedFeeds);
-        }
-        feedListLock.unlock();
-        GpodnetSyncService.sendSyncSubscriptionsIntent(ClientConfig.applicationCallbacks.getApplicationInstance());
-    }
-
-    public static void addRemovedFeed(String feed) {
-        ensurePreferencesLoaded();
-        feedListLock.lock();
-        if (removedFeeds.add(feed)) {
-            writePreference(PREF_SYNC_REMOVED, removedFeeds);
-        }
-        if (addedFeeds.remove(feed)) {
-            writePreference(PREF_SYNC_ADDED, addedFeeds);
-        }
-        feedListLock.unlock();
-        GpodnetSyncService.sendSyncSubscriptionsIntent(ClientConfig.applicationCallbacks.getApplicationInstance());
-    }
-
-    public static Set<String> getAddedFeedsCopy() {
-        ensurePreferencesLoaded();
-        Set<String> copy = new HashSet<>();
-        feedListLock.lock();
-        copy.addAll(addedFeeds);
-        feedListLock.unlock();
-        return copy;
-    }
-
-    public static void removeAddedFeeds(Collection<String> removed) {
-        ensurePreferencesLoaded();
-        feedListLock.lock();
-        addedFeeds.removeAll(removed);
-        writePreference(PREF_SYNC_ADDED, addedFeeds);
-        feedListLock.unlock();
-    }
-
-    public static Set<String> getRemovedFeedsCopy() {
-        ensurePreferencesLoaded();
-        Set<String> copy = new HashSet<>();
-        feedListLock.lock();
-        copy.addAll(removedFeeds);
-        feedListLock.unlock();
-        return copy;
-    }
-
-    public static void removeRemovedFeeds(Collection<String> removed) {
-        ensurePreferencesLoaded();
-        feedListLock.lock();
-        removedFeeds.removeAll(removed);
-        writePreference(PREF_SYNC_REMOVED, removedFeeds);
-        feedListLock.unlock();
-    }
-
-    public static void enqueueEpisodeAction(GpodnetEpisodeAction action) {
-        ensurePreferencesLoaded();
-        feedListLock.lock();
-        queuedEpisodeActions.add(action);
-        writePreference(PREF_SYNC_EPISODE_ACTIONS, writeEpisodeActionsToString(queuedEpisodeActions));
-        feedListLock.unlock();
-        GpodnetSyncService.sendSyncActionsIntent(ClientConfig.applicationCallbacks.getApplicationInstance());
-    }
-
-    public static List<GpodnetEpisodeAction> getQueuedEpisodeActions() {
-        ensurePreferencesLoaded();
-        List<GpodnetEpisodeAction> copy = new ArrayList<>();
-        feedListLock.lock();
-        copy.addAll(queuedEpisodeActions);
-        feedListLock.unlock();
-        return copy;
-    }
-
-    public static void removeQueuedEpisodeActions(Collection<GpodnetEpisodeAction> queued) {
-        ensurePreferencesLoaded();
-        feedListLock.lock();
-        queuedEpisodeActions.removeAll(queued);
-        writePreference(PREF_SYNC_EPISODE_ACTIONS, writeEpisodeActionsToString(queuedEpisodeActions));
-        feedListLock.unlock();
-    }
-
     /**
      * Returns true if device ID, username and password have a non-null value
      */
@@ -304,57 +109,10 @@ public class GpodnetPreferences {
         setUsername(null);
         setPassword(null);
         setDeviceID(null);
-        feedListLock.lock();
+        SyncService.clearQueue(ClientConfig.applicationCallbacks.getApplicationInstance());
-        addedFeeds.clear();
-        writePreference(PREF_SYNC_ADDED, addedFeeds);
-        removedFeeds.clear();
-        writePreference(PREF_SYNC_REMOVED, removedFeeds);
-        queuedEpisodeActions.clear();
-        writePreference(PREF_SYNC_EPISODE_ACTIONS, writeEpisodeActionsToString(queuedEpisodeActions));
-        feedListLock.unlock();
-        setLastSubscriptionSyncTimestamp(0);
-        setLastSyncAttempt(false, 0);
         UserPreferences.setGpodnetNotificationsEnabled();
     }
 
-    private static Set<String> readListFromString(String s) {
-        Set<String> result = new HashSet<>();
-        Collections.addAll(result, s.split(" "));
-        return result;
-    }
-
-    private static String writeListToString(Collection<String> c) {
-        StringBuilder result = new StringBuilder();
-        for (String item : c) {
-            result.append(item);
-            result.append(" ");
-        }
-        return result.toString().trim();
-    }
-
-    private static List<GpodnetEpisodeAction> readEpisodeActionsFromString(String s) {
-        String[] lines = s.split("\n");
-        List<GpodnetEpisodeAction> result = new ArrayList<>(lines.length);
-        for(String line : lines) {
-            if(TextUtils.isEmpty(line)) {
-                GpodnetEpisodeAction action = GpodnetEpisodeAction.readFromString(line);
-                if(action != null) {
-                    result.add(GpodnetEpisodeAction.readFromString(line));
-                }
-            }
-        }
-        return result;
-    }
-
-    private static String writeEpisodeActionsToString(Collection<GpodnetEpisodeAction> c) {
-        StringBuilder result = new StringBuilder();
-        for(GpodnetEpisodeAction item : c) {
-            result.append(item.writeToString());
-            result.append("\n");
-        }
-        return result.toString();
-    }
-
     private static String checkGpodnetHostname(String value) {
         int startIndex = 0;
         if (value.startsWith("http://")) {

core/src/main/java/de/danoeh/antennapod/core/service/GpodnetSyncService.java

@@ -1,363 +0,0 @@
-package de.danoeh.antennapod.core.service;
-
-import android.app.Notification;
-import android.app.NotificationManager;
-import android.app.PendingIntent;
-import android.content.Context;
-import android.content.Intent;
-import androidx.annotation.NonNull;
-import androidx.core.app.NotificationCompat;
-import androidx.core.app.SafeJobIntentService;
-import androidx.collection.ArrayMap;
-import android.util.Log;
-import android.util.Pair;
-
-import java.util.Collection;
-import java.util.List;
-import java.util.Map;
-import java.util.concurrent.atomic.AtomicInteger;
-
-import de.danoeh.antennapod.core.ClientConfig;
-import de.danoeh.antennapod.core.R;
-import de.danoeh.antennapod.core.feed.Feed;
-import de.danoeh.antennapod.core.feed.FeedItem;
-import de.danoeh.antennapod.core.feed.FeedMedia;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetService;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceAuthenticationException;
-import de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeAction;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeActionGetResponse;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeActionPostResponse;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetSubscriptionChange;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetUploadChangesResponse;
-import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
-import de.danoeh.antennapod.core.preferences.UserPreferences;
-import de.danoeh.antennapod.core.storage.DBReader;
-import de.danoeh.antennapod.core.storage.DBTasks;
-import de.danoeh.antennapod.core.storage.DBWriter;
-import de.danoeh.antennapod.core.storage.DownloadRequestException;
-import de.danoeh.antennapod.core.storage.DownloadRequester;
-import de.danoeh.antennapod.core.util.NetworkUtils;
-import de.danoeh.antennapod.core.util.URLChecker;
-import de.danoeh.antennapod.core.util.gui.NotificationUtils;
-
-/**
- * Synchronizes local subscriptions with gpodder.net service. The service should be started with ACTION_SYNC as an action argument.
- * This class also provides static methods for starting the GpodnetSyncService.
- */
-public class GpodnetSyncService extends SafeJobIntentService {
-
-    private static final String TAG = "GpodnetSyncService";
-
-    private static final long WAIT_INTERVAL = 5000L;
-
-    private static final String ARG_ACTION = "action";
-
-    private static final String ACTION_SYNC = "de.danoeh.antennapod.intent.action.sync";
-    private static final String ACTION_SYNC_SUBSCRIPTIONS = "de.danoeh.antennapod.intent.action.sync_subscriptions";
-    private static final String ACTION_SYNC_ACTIONS = "de.danoeh.antennapod.intent.action.sync_ACTIONS";
-
-    private GpodnetService service;
-
-    private static final AtomicInteger syncActionCount = new AtomicInteger(0);
-    private static boolean syncSubscriptions = false;
-    private static boolean syncActions = false;
-
-    private static final int JOB_ID = -17000;
-
-    private static void enqueueWork(Context context, Intent intent) {
-        enqueueWork(context, GpodnetSyncService.class, JOB_ID, intent);
-    }
-
-    @Override
-    protected void onHandleWork(@NonNull Intent intent) {
-        final String action = intent.getStringExtra(ARG_ACTION);
-        if (action != null) {
-            switch(action) {
-                case ACTION_SYNC:
-                    syncSubscriptions = true;
-                    syncActions = true;
-                    break;
-                case ACTION_SYNC_SUBSCRIPTIONS:
-                    syncSubscriptions = true;
-                    break;
-                case ACTION_SYNC_ACTIONS:
-                    syncActions = true;
-                    break;
-                default:
-                    Log.e(TAG, "Received invalid intent: action argument is invalid");
-            }
-            if(syncSubscriptions || syncActions) {
-                Log.d(TAG, String.format("Waiting %d milliseconds before uploading changes", WAIT_INTERVAL));
-                int syncActionId = syncActionCount.incrementAndGet();
-                try {
-                    Thread.sleep(WAIT_INTERVAL);
-                } catch (InterruptedException e) {
-                    e.printStackTrace();
-                }
-                if (syncActionId == syncActionCount.get()) {
-                    // onHandleWork was not called again in the meantime
-                    sync();
-                }
-            }
-        } else {
-            Log.e(TAG, "Received invalid intent: action argument is null");
-        }
-    }
-
-    private synchronized GpodnetService tryLogin() throws GpodnetServiceException {
-        if (service == null) {
-            service = new GpodnetService();
-            service.authenticate(GpodnetPreferences.getUsername(), GpodnetPreferences.getPassword());
-        }
-        return service;
-    }
-
-
-    private synchronized void sync() {
-        if (!GpodnetPreferences.loggedIn() || !NetworkUtils.networkAvailable()) {
-            stopForeground(true);
-            stopSelf();
-            return;
-        }
-        boolean initialSync =  GpodnetPreferences.getLastSubscriptionSyncTimestamp() == 0 &&
-                GpodnetPreferences.getLastEpisodeActionsSyncTimestamp() == 0;
-        if(syncSubscriptions) {
-            syncSubscriptionChanges();
-            syncSubscriptions = false;
-        }
-        if(syncActions) {
-            // we only sync episode actions after the subscriptions have been added to the database
-            if(!initialSync) {
-                syncEpisodeActions();
-            }
-            syncActions = false;
-        }
-    }
-
-    private synchronized void syncSubscriptionChanges() {
-        final long timestamp = GpodnetPreferences.getLastSubscriptionSyncTimestamp();
-        try {
-            final List<String> localSubscriptions = DBReader.getFeedListDownloadUrls();
-            Collection<String> localAdded = GpodnetPreferences.getAddedFeedsCopy();
-            Collection<String> localRemoved = GpodnetPreferences.getRemovedFeedsCopy();
-            GpodnetService service = tryLogin();
-
-            // first sync: download all subscriptions...
-            GpodnetSubscriptionChange subscriptionChanges = service.getSubscriptionChanges(GpodnetPreferences.getUsername(),
-                    GpodnetPreferences.getDeviceID(), timestamp);
-            long newTimeStamp = subscriptionChanges.getTimestamp();
-
-            Log.d(TAG, "Downloaded subscription changes: " + subscriptionChanges);
-            processSubscriptionChanges(localSubscriptions, localAdded, localRemoved, subscriptionChanges);
-
-            if(timestamp == 0) {
-                // this is this apps first sync with gpodder:
-                // only submit changes gpodder has not just sent us
-                localAdded = localSubscriptions;
-                localAdded.removeAll(subscriptionChanges.getAdded());
-                localRemoved.removeAll(subscriptionChanges.getRemoved());
-            }
-            if(localAdded.size() > 0 || localRemoved.size() > 0) {
-                Log.d(TAG, String.format("Uploading subscriptions, Added: %s\nRemoved: %s",
-                        localAdded, localRemoved));
-                GpodnetUploadChangesResponse uploadResponse = service.uploadChanges(GpodnetPreferences.getUsername(),
-                        GpodnetPreferences.getDeviceID(), localAdded, localRemoved);
-                newTimeStamp = uploadResponse.timestamp;
-                Log.d(TAG, "Upload changes response: " + uploadResponse);
-                GpodnetPreferences.removeAddedFeeds(localAdded);
-                GpodnetPreferences.removeRemovedFeeds(localRemoved);
-            }
-            GpodnetPreferences.setLastSubscriptionSyncTimestamp(newTimeStamp);
-            GpodnetPreferences.setLastSyncAttempt(true, System.currentTimeMillis());
-            clearErrorNotifications();
-        } catch (GpodnetServiceException e) {
-            e.printStackTrace();
-            updateErrorNotification(e);
-        } catch (DownloadRequestException e) {
-            e.printStackTrace();
-        }
-    }
-
-    private synchronized void processSubscriptionChanges(List<String> localSubscriptions,
-                                                         Collection<String> localAdded,
-                                                         Collection<String> localRemoved,
-                                                         GpodnetSubscriptionChange changes) throws DownloadRequestException {
-        // local changes are always superior to remote changes!
-        // add subscription if (1) not already subscribed and (2) not just unsubscribed
-        for (String downloadUrl : changes.getAdded()) {
-            if (!URLChecker.containsUrl(localSubscriptions, downloadUrl) && !localRemoved.contains(downloadUrl)) {
-                Feed feed = new Feed(downloadUrl, null);
-                DownloadRequester.getInstance().downloadFeed(this, feed);
-            }
-        }
-        // remove subscription if not just subscribed (again)
-        for (String downloadUrl : changes.getRemoved()) {
-            if (!localAdded.contains(downloadUrl)) {
-                DBTasks.removeFeedWithDownloadUrl(GpodnetSyncService.this, downloadUrl);
-            }
-        }
-    }
-
-    private synchronized void syncEpisodeActions() {
-        final long timestamp = GpodnetPreferences.getLastEpisodeActionsSyncTimestamp();
-        Log.d(TAG, "last episode actions sync timestamp: " + timestamp);
-        try {
-            GpodnetService service = tryLogin();
-
-            // download episode actions
-            GpodnetEpisodeActionGetResponse getResponse = service.getEpisodeChanges(timestamp);
-            long lastUpdate = getResponse.getTimestamp();
-            Log.d(TAG, "Downloaded episode actions: " + getResponse);
-            List<GpodnetEpisodeAction> remoteActions = getResponse.getEpisodeActions();
-
-            List<GpodnetEpisodeAction> localActions = GpodnetPreferences.getQueuedEpisodeActions();
-            processEpisodeActions(localActions, remoteActions);
-
-            // upload local actions
-            if(localActions.size() > 0) {
-                Log.d(TAG, "Uploading episode actions: " + localActions);
-                GpodnetEpisodeActionPostResponse postResponse = service.uploadEpisodeActions(localActions);
-                lastUpdate = postResponse.timestamp;
-                Log.d(TAG, "Upload episode response: " + postResponse);
-                GpodnetPreferences.removeQueuedEpisodeActions(localActions);
-            }
-            GpodnetPreferences.setLastEpisodeActionsSyncTimestamp(lastUpdate);
-            GpodnetPreferences.setLastSyncAttempt(true, System.currentTimeMillis());
-            clearErrorNotifications();
-        } catch (GpodnetServiceException e) {
-            e.printStackTrace();
-            updateErrorNotification(e);
-        }
-    }
-
-
-    private synchronized void processEpisodeActions(List<GpodnetEpisodeAction> localActions,
-                                                    List<GpodnetEpisodeAction> remoteActions) {
-        if(remoteActions.size() == 0) {
-            return;
-        }
-        Map<Pair<String, String>, GpodnetEpisodeAction> localMostRecentPlayAction = new ArrayMap<>();
-        for(GpodnetEpisodeAction action : localActions) {
-            Pair<String, String> key = new Pair<>(action.getPodcast(), action.getEpisode());
-            GpodnetEpisodeAction mostRecent = localMostRecentPlayAction.get(key);
-            if (mostRecent == null || mostRecent.getTimestamp() == null) {
-                localMostRecentPlayAction.put(key, action);
-            } else if (mostRecent.getTimestamp().before(action.getTimestamp())) {
-                localMostRecentPlayAction.put(key, action);
-            }
-        }
-
-        // make sure more recent local actions are not overwritten by older remote actions
-        Map<Pair<String, String>, GpodnetEpisodeAction> mostRecentPlayAction = new ArrayMap<>();
-        for (GpodnetEpisodeAction action : remoteActions) {
-            switch (action.getAction()) {
-                case NEW:
-                    FeedItem newItem = DBReader.getFeedItem(action.getPodcast(), action.getEpisode());
-                    if(newItem != null) {
-                        DBWriter.markItemPlayed(newItem, FeedItem.UNPLAYED, true);
-                    } else {
-                        Log.i(TAG, "Unknown feed item: " + action);
-                    }
-                    break;
-                case DOWNLOAD:
-                    break;
-                case PLAY:
-                    Pair<String, String> key = new Pair<>(action.getPodcast(), action.getEpisode());
-                    GpodnetEpisodeAction localMostRecent = localMostRecentPlayAction.get(key);
-                    if(localMostRecent == null ||
-                            localMostRecent.getTimestamp() == null ||
-                            localMostRecent.getTimestamp().before(action.getTimestamp())) {
-                        GpodnetEpisodeAction mostRecent = mostRecentPlayAction.get(key);
-                        if (mostRecent == null || mostRecent.getTimestamp() == null) {
-                            mostRecentPlayAction.put(key, action);
-                        } else if (action.getTimestamp() != null && mostRecent.getTimestamp().before(action.getTimestamp())) {
-                            mostRecentPlayAction.put(key, action);
-                        } else {
-                            Log.d(TAG, "No date information in action, skipping it");
-                        }
-                    }
-                    break;
-                case DELETE:
-                    // NEVER EVER call DBWriter.deleteFeedMediaOfItem() here, leads to an infinite loop
-                    break;
-            }
-        }
-        for (GpodnetEpisodeAction action : mostRecentPlayAction.values()) {
-            FeedItem playItem = DBReader.getFeedItem(action.getPodcast(), action.getEpisode());
-            if (playItem != null) {
-                FeedMedia media = playItem.getMedia();
-                media.setPosition(action.getPosition() * 1000);
-                DBWriter.setFeedMedia(media);
-                if(playItem.getMedia().hasAlmostEnded()) {
-                    DBWriter.markItemPlayed(playItem, FeedItem.PLAYED, true);
-                    DBWriter.addItemToPlaybackHistory(playItem.getMedia());
-                }
-            }
-        }
-    }
-
-    private void clearErrorNotifications() {
-        NotificationManager nm = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
-        nm.cancel(R.id.notification_gpodnet_sync_error);
-        nm.cancel(R.id.notification_gpodnet_sync_autherror);
-    }
-
-    private void updateErrorNotification(GpodnetServiceException exception) {
-     Log.d(TAG, "Posting error notification");
-        GpodnetPreferences.setLastSyncAttempt(false, System.currentTimeMillis());
-
-        final String title;
-        final String description;
-        final int id;
-        if (exception instanceof GpodnetServiceAuthenticationException) {
-            title = getString(R.string.gpodnetsync_auth_error_title);
-            description = getString(R.string.gpodnetsync_auth_error_descr);
-            id = R.id.notification_gpodnet_sync_autherror;
-        } else {
-            if (UserPreferences.gpodnetNotificationsEnabled()) {
-                title = getString(R.string.gpodnetsync_error_title);
-                description = getString(R.string.gpodnetsync_error_descr) + exception.getMessage();
-                id = R.id.notification_gpodnet_sync_error;
-            } else {
-                return;
-            }
-        }
-
-        PendingIntent activityIntent = ClientConfig.gpodnetCallbacks.getGpodnetSyncServiceErrorNotificationPendingIntent(this);
-        Notification notification = new NotificationCompat.Builder(this, NotificationUtils.CHANNEL_ID_ERROR)
-                .setContentTitle(title)
-                .setContentText(description)
-                .setContentIntent(activityIntent)
-                .setSmallIcon(R.drawable.ic_notification_sync_error)
-                .setAutoCancel(true)
-                .setVisibility(NotificationCompat.VISIBILITY_PUBLIC)
-                .build();
-        NotificationManager nm = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
-        nm.notify(id, notification);
-    }
-
-    public static void sendSyncIntent(Context context) {
-        if (GpodnetPreferences.loggedIn()) {
-            Intent intent = new Intent(context, GpodnetSyncService.class);
-            intent.putExtra(ARG_ACTION, ACTION_SYNC);
-            enqueueWork(context, intent);
-        }
-    }
-
-    public static void sendSyncSubscriptionsIntent(Context context) {
-        if (GpodnetPreferences.loggedIn()) {
-            Intent intent = new Intent(context, GpodnetSyncService.class);
-            intent.putExtra(ARG_ACTION, ACTION_SYNC_SUBSCRIPTIONS);
-            enqueueWork(context, intent);
-        }
-    }
-
-    public static void sendSyncActionsIntent(Context context) {
-        if (GpodnetPreferences.loggedIn()) {
-            Intent intent = new Intent(context, GpodnetSyncService.class);
-            intent.putExtra(ARG_ACTION, ACTION_SYNC_ACTIONS);
-            enqueueWork(context, intent);
-        }
-    }
-}

core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadService.java

@@ -17,6 +17,7 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
 
+import de.danoeh.antennapod.core.sync.SyncService;
 import org.apache.commons.io.FileUtils;
 import org.greenrobot.eventbus.EventBus;
 
@@ -42,9 +43,7 @@ import de.danoeh.antennapod.core.event.FeedItemEvent;
 import de.danoeh.antennapod.core.feed.Feed;
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.FeedMedia;
-import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
-import de.danoeh.antennapod.core.service.GpodnetSyncService;
 import de.danoeh.antennapod.core.service.download.handler.FailedDownloadHandler;
 import de.danoeh.antennapod.core.service.download.handler.FeedSyncTask;
 import de.danoeh.antennapod.core.service.download.handler.MediaDownloadedHandler;
@@ -234,11 +233,7 @@ public class DownloadService extends Service {
 
         // if this was the initial gpodder sync, i.e. we just synced the feeds successfully,
         // it is now time to sync the episode actions
-        if (GpodnetPreferences.loggedIn() &&
+        SyncService.sync(this);
-                GpodnetPreferences.getLastSubscriptionSyncTimestamp() > 0 &&
-                GpodnetPreferences.getLastEpisodeActionsSyncTimestamp() == 0) {
-            GpodnetSyncService.sendSyncActionsIntent(this);
-        }
 
         // start auto download in case anything new has shown up
         DBTasks.autodownloadUndownloadedItems(getApplicationContext());
@@ -554,7 +549,7 @@ public class DownloadService extends Service {
     }
 
     /**
-     * Check if there's something else to download, otherwise stop
+     * Check if there's something else to download, otherwise stop.
      */
     private void queryDownloads() {
         Log.d(TAG, numberOfDownloads.get() + " downloads left");
@@ -562,7 +557,11 @@ public class DownloadService extends Service {
         if (numberOfDownloads.get() <= 0 && DownloadRequester.getInstance().hasNoDownloads()) {
             Log.d(TAG, "Number of downloads is " + numberOfDownloads.get() + ", attempting shutdown");
             stopSelf();
-            notificationUpdater.run();
+            if (notificationUpdater != null) {
+                notificationUpdater.run();
+            } else {
+                Log.d(TAG, "Skipping notification update");
+            }
         } else {
             setupNotificationUpdater();
             Notification notification = notificationManager.updateNotifications(

core/src/main/java/de/danoeh/antennapod/core/service/download/handler/MediaDownloadedHandler.java

@@ -12,14 +12,14 @@ import java.util.concurrent.ExecutionException;
 import de.danoeh.antennapod.core.event.UnreadItemsUpdateEvent;
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.FeedMedia;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeAction;
-import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
 import de.danoeh.antennapod.core.service.download.DownloadRequest;
 import de.danoeh.antennapod.core.service.download.DownloadStatus;
 import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.util.ChapterUtils;
 import de.danoeh.antennapod.core.util.DownloadError;
+import de.danoeh.antennapod.core.sync.SyncService;
+import de.danoeh.antennapod.core.sync.model.EpisodeAction;
 import org.greenrobot.eventbus.EventBus;
 
 /**
@@ -99,12 +99,11 @@ public class MediaDownloadedHandler implements Runnable {
                     DownloadError.ERROR_DB_ACCESS_ERROR, false, e.getMessage(), request.isInitiatedByUser());
         }
 
-        if (GpodnetPreferences.loggedIn() && item != null) {
+        if (item != null) {
-            GpodnetEpisodeAction action = new GpodnetEpisodeAction.Builder(item, GpodnetEpisodeAction.Action.DOWNLOAD)
+            EpisodeAction action = new EpisodeAction.Builder(item, EpisodeAction.DOWNLOAD)
-                    .currentDeviceId()
                     .currentTimestamp()
                     .build();
-            GpodnetPreferences.enqueueEpisodeAction(action);
+            SyncService.enqueueEpisodeAction(context, action);
         }
     }
 

core/src/main/java/de/danoeh/antennapod/core/storage/DBReader.java

@@ -21,6 +21,7 @@ import de.danoeh.antennapod.core.feed.FeedMedia;
 import de.danoeh.antennapod.core.feed.FeedPreferences;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
 import de.danoeh.antennapod.core.service.download.DownloadStatus;
+import de.danoeh.antennapod.core.sync.model.EpisodeAction;
 import de.danoeh.antennapod.core.util.LongIntMap;
 import de.danoeh.antennapod.core.util.LongList;
 import de.danoeh.antennapod.core.util.comparator.DownloadStatusComparator;
@@ -347,6 +348,31 @@ public final class DBReader {
         }
     }
 
+    /**
+     * Loads a list of FeedItems whose episode has been played.
+     *
+     * @return A list of FeedItems whose episdoe has been played.
+     */
+    @NonNull
+    public static List<FeedItem> getPlayedItems() {
+        Log.d(TAG, "getPlayedItems() called");
+
+        PodDBAdapter adapter = PodDBAdapter.getInstance();
+        adapter.open();
+        Cursor cursor = null;
+        try {
+            cursor = adapter.getPlayedItemsCursor();
+            List<FeedItem> items = extractItemlistFromCursor(adapter, cursor);
+            loadAdditionalFeedItemListData(items);
+            return items;
+        } finally {
+            if (cursor != null) {
+                cursor.close();
+            }
+            adapter.close();
+        }
+    }
+
     /**
      * Loads a list of FeedItems that are considered new.
      * Excludes items from feeds that do not have keep updated enabled.
@@ -629,8 +655,16 @@ public final class DBReader {
         }
     }
 
+    /**
+     * Loads a specific FeedItem from the database.
+     *
+     * @param podcastUrl the corresponding feed's url
+     * @param episodeUrl the feed item's url
+     * @return The FeedItem or null if the FeedItem could not be found.
+     *          Does NOT load additional attributes like feed or queue state.
+     */
     @Nullable
-    private static FeedItem getFeedItem(final String podcastUrl, final String episodeUrl, PodDBAdapter adapter) {
+    private static FeedItem getFeedItemByUrl(final String podcastUrl, final String episodeUrl, PodDBAdapter adapter) {
         Log.d(TAG, "Loading feeditem with podcast url " + podcastUrl + " and episode url " + episodeUrl);
         Cursor cursor = null;
         try {
@@ -639,15 +673,10 @@ public final class DBReader {
                 return null;
             }
             List<FeedItem> list = extractItemlistFromCursor(adapter, cursor);
-            FeedItem item = null;
             if (!list.isEmpty()) {
-                item = list.get(0);
+                return list.get(0);
-                loadAdditionalFeedItemListData(list);
-                if (item.hasChapters()) {
-                    loadChaptersOfFeedItem(adapter, item);
-                }
             }
-            return item;
+            return null;
         } finally {
             if (cursor != null) {
                 cursor.close();
@@ -702,16 +731,16 @@ public final class DBReader {
      *
      * @param podcastUrl the corresponding feed's url
      * @param episodeUrl the feed item's url
-     * @return The FeedItem or null if the FeedItem could not be found. All FeedComponent-attributes
+     * @return The FeedItem or null if the FeedItem could not be found.
-     * as well as chapter marks of the FeedItem will also be loaded from the database.
+     *          Does NOT load additional attributes like feed or queue state.
      */
-    public static FeedItem getFeedItem(final String podcastUrl, final String episodeUrl) {
+    public static FeedItem getFeedItemByUrl(final String podcastUrl, final String episodeUrl) {
         Log.d(TAG, "getFeedItem() called with: " + "podcastUrl = [" + podcastUrl + "], episodeUrl = [" + episodeUrl + "]");
 
         PodDBAdapter adapter = PodDBAdapter.getInstance();
         adapter.open();
         try {
-            return getFeedItem(podcastUrl, episodeUrl, adapter);
+            return getFeedItemByUrl(podcastUrl, episodeUrl, adapter);
         } finally {
             adapter.close();
         }

core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java

@@ -17,8 +17,8 @@ import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.FeedMedia;
 import de.danoeh.antennapod.core.feed.FeedPreferences;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
-import de.danoeh.antennapod.core.service.GpodnetSyncService;
 import de.danoeh.antennapod.core.service.download.DownloadStatus;
+import de.danoeh.antennapod.core.sync.SyncService;
 import de.danoeh.antennapod.core.util.DownloadError;
 import de.danoeh.antennapod.core.util.LongList;
 import de.danoeh.antennapod.core.util.comparator.FeedItemPubdateComparator;
@@ -123,9 +123,7 @@ public final class DBTasks {
         SharedPreferences prefs = context.getSharedPreferences(PREF_NAME, MODE_PRIVATE);
         prefs.edit().putLong(PREF_LAST_REFRESH, System.currentTimeMillis()).apply();
 
-        if (ClientConfig.gpodnetCallbacks.gpodnetEnabled()) {
+        SyncService.sync(context);
-            GpodnetSyncService.sendSyncIntent(context);
-        }
         // Note: automatic download of episodes will be done but not here.
         // Instead it is done after all feeds have been refreshed (asynchronously),
         // in DownloadService.onDestroy()

core/src/main/java/de/danoeh/antennapod/core/storage/DBWriter.java

@@ -7,6 +7,8 @@ import android.util.Log;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import de.danoeh.antennapod.core.sync.SyncService;
+import de.danoeh.antennapod.core.sync.model.EpisodeAction;
 import org.greenrobot.eventbus.EventBus;
 
 import java.io.File;
@@ -34,7 +36,6 @@ import de.danoeh.antennapod.core.feed.FeedEvent;
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.FeedMedia;
 import de.danoeh.antennapod.core.feed.FeedPreferences;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeAction;
 import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
 import de.danoeh.antennapod.core.preferences.PlaybackPreferences;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
@@ -118,11 +119,10 @@ public class DBWriter {
             // Gpodder: queue delete action for synchronization
             if (GpodnetPreferences.loggedIn()) {
                 FeedItem item = media.getItem();
-                GpodnetEpisodeAction action = new GpodnetEpisodeAction.Builder(item, GpodnetEpisodeAction.Action.DELETE)
+                EpisodeAction action = new EpisodeAction.Builder(item, EpisodeAction.DELETE)
-                        .currentDeviceId()
                         .currentTimestamp()
                         .build();
-                GpodnetPreferences.enqueueEpisodeAction(action);
+                SyncService.enqueueEpisodeAction(context, action);
             }
         }
         EventBus.getDefault().post(FeedItemEvent.deletedMedia(Collections.singletonList(media.getItem())));
@@ -169,9 +169,7 @@ public class DBWriter {
                 adapter.removeFeed(feed);
                 adapter.close();
 
-                if (ClientConfig.gpodnetCallbacks.gpodnetEnabled()) {
+                SyncService.enqueueFeedRemoved(context, feed.getDownload_url());
-                    GpodnetPreferences.addRemovedFeed(feed.getDownload_url());
-                }
                 EventBus.getDefault().post(new FeedListUpdateEvent(feed));
 
                 // we assume we also removed download log entries for the feed or its media files.
@@ -727,10 +725,8 @@ public class DBWriter {
             adapter.setCompleteFeed(feeds);
             adapter.close();
 
-            if (ClientConfig.gpodnetCallbacks.gpodnetEnabled()) {
+            for (Feed feed : feeds) {
-                for (Feed feed : feeds) {
+                SyncService.enqueueFeedAdded(context, feed.getDownload_url());
-                    GpodnetPreferences.addAddedFeed(feed.getDownload_url());
-                }
             }
 
             BackupManager backupManager = new BackupManager(context);
@@ -747,6 +743,15 @@ public class DBWriter {
         });
     }
 
+    public static Future<?> setItemList(final List<FeedItem> items) {
+        return dbExec.submit(() -> {
+            PodDBAdapter adapter = PodDBAdapter.getInstance();
+            adapter.open();
+            adapter.setFeedItemlist(items);
+            adapter.close();
+        });
+    }
+
     /**
      * Saves a FeedMedia object in the database. This method will save all attributes of the FeedMedia object. The
      * contents of FeedComponent-attributes (e.g. the FeedMedia's 'item'-attribute) will not be saved.

core/src/main/java/de/danoeh/antennapod/core/storage/PodDBAdapter.java

@@ -1023,6 +1023,15 @@ public class PodDBAdapter {
         return db.rawQuery(query, null);
     }
 
+    public Cursor getPlayedItemsCursor() {
+        final String query = "SELECT " + SEL_FI_SMALL_STR
+                + " FROM " + TABLE_NAME_FEED_ITEMS
+                + " INNER JOIN " + TABLE_NAME_FEED_MEDIA
+                + " ON " + TABLE_NAME_FEED_ITEMS + "." + KEY_ID + "=" + TABLE_NAME_FEED_MEDIA + "." + KEY_FEEDITEM
+                + " WHERE " + TABLE_NAME_FEED_ITEMS + "." + KEY_READ + "=" + FeedItem.PLAYED;
+        return db.rawQuery(query, null);
+    }
+
     /**
      * Returns a cursor which contains feed media objects with a playback
      * completion date in ascending order.

core/src/main/java/de/danoeh/antennapod/core/sync/SyncService.java

@@ -0,0 +1,461 @@
+package de.danoeh.antennapod.core.sync;
+
+import android.app.Notification;
+import android.app.NotificationManager;
+import android.app.PendingIntent;
+import android.content.Context;
+import android.content.Intent;
+import android.content.SharedPreferences;
+import android.util.Log;
+import androidx.annotation.NonNull;
+import androidx.collection.ArrayMap;
+import androidx.core.app.NotificationCompat;
+import androidx.core.util.Pair;
+import androidx.work.BackoffPolicy;
+import androidx.work.Constraints;
+import androidx.work.ExistingWorkPolicy;
+import androidx.work.NetworkType;
+import androidx.work.OneTimeWorkRequest;
+import androidx.work.WorkManager;
+import androidx.work.Worker;
+import androidx.work.WorkerParameters;
+import de.danoeh.antennapod.core.R;
+import de.danoeh.antennapod.core.event.SyncServiceEvent;
+import de.danoeh.antennapod.core.feed.Feed;
+import de.danoeh.antennapod.core.feed.FeedItem;
+import de.danoeh.antennapod.core.feed.FeedMedia;
+import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
+import de.danoeh.antennapod.core.preferences.UserPreferences;
+import de.danoeh.antennapod.core.service.download.AntennapodHttpClient;
+import de.danoeh.antennapod.core.storage.DBReader;
+import de.danoeh.antennapod.core.storage.DBTasks;
+import de.danoeh.antennapod.core.storage.DBWriter;
+import de.danoeh.antennapod.core.storage.DownloadRequestException;
+import de.danoeh.antennapod.core.storage.DownloadRequester;
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.model.EpisodeAction;
+import de.danoeh.antennapod.core.sync.model.EpisodeActionChanges;
+import de.danoeh.antennapod.core.sync.model.ISyncService;
+import de.danoeh.antennapod.core.sync.model.SubscriptionChanges;
+import de.danoeh.antennapod.core.sync.model.SyncServiceException;
+import de.danoeh.antennapod.core.sync.model.UploadChangesResponse;
+import de.danoeh.antennapod.core.util.URLChecker;
+import de.danoeh.antennapod.core.util.gui.NotificationUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.greenrobot.eventbus.EventBus;
+import org.json.JSONArray;
+import org.json.JSONException;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
+
+public class SyncService extends Worker {
+    private static final String PREF_NAME = "SyncService";
+    private static final String PREF_LAST_SUBSCRIPTION_SYNC_TIMESTAMP = "last_sync_timestamp";
+    private static final String PREF_LAST_EPISODE_ACTIONS_SYNC_TIMESTAMP = "last_episode_actions_sync_timestamp";
+    private static final String PREF_QUEUED_FEEDS_ADDED = "sync_added";
+    private static final String PREF_QUEUED_FEEDS_REMOVED = "sync_removed";
+    private static final String PREF_QUEUED_EPISODE_ACTIONS = "sync_queued_episode_actions";
+    private static final String PREF_LAST_SYNC_ATTEMPT_TIMESTAMP = "last_sync_attempt_timestamp";
+    private static final String PREF_LAST_SYNC_ATTEMPT_SUCCESS = "last_sync_attempt_success";
+    private static final String TAG = "SyncService";
+    private static final String WORK_ID_SYNC = "SyncServiceWorkId";
+    private static final Object lock = new Object();
+
+    private ISyncService syncServiceImpl;
+
+    public SyncService(@NonNull Context context, @NonNull WorkerParameters params) {
+        super(context, params);
+    }
+
+    @Override
+    @NonNull
+    public Result doWork() {
+        if (!GpodnetPreferences.loggedIn()) {
+            return Result.success();
+        }
+        syncServiceImpl = new GpodnetService(AntennapodHttpClient.getHttpClient(), GpodnetService.DEFAULT_BASE_HOST);
+        SharedPreferences.Editor prefs = getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE)
+                .edit();
+        prefs.putLong(PREF_LAST_SYNC_ATTEMPT_TIMESTAMP, System.currentTimeMillis()).apply();
+        try {
+            syncServiceImpl.login();
+            EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_subscriptions));
+            syncSubscriptions();
+            syncEpisodeActions();
+            syncServiceImpl.logout();
+            clearErrorNotifications();
+            EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_success));
+            prefs.putBoolean(PREF_LAST_SYNC_ATTEMPT_SUCCESS, true).apply();
+            return Result.success();
+        } catch (SyncServiceException e) {
+            EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_error));
+            prefs.putBoolean(PREF_LAST_SYNC_ATTEMPT_SUCCESS, false).apply();
+            Log.e(TAG, Log.getStackTraceString(e));
+            updateErrorNotification(e);
+            return Result.retry();
+        }
+    }
+
+    public static void clearQueue(Context context) {
+        synchronized (lock) {
+            context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE).edit()
+                    .putLong(PREF_LAST_SUBSCRIPTION_SYNC_TIMESTAMP, 0)
+                    .putLong(PREF_LAST_EPISODE_ACTIONS_SYNC_TIMESTAMP, 0)
+                    .putLong(PREF_LAST_SYNC_ATTEMPT_TIMESTAMP, 0)
+                    .putString(PREF_QUEUED_EPISODE_ACTIONS, "[]")
+                    .putString(PREF_QUEUED_FEEDS_ADDED, "[]")
+                    .putString(PREF_QUEUED_FEEDS_REMOVED, "[]")
+                    .apply();
+        }
+    }
+
+    public static void enqueueFeedAdded(Context context, String downloadUrl) {
+        synchronized (lock) {
+            try {
+                SharedPreferences prefs = context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
+                String json = prefs.getString(PREF_QUEUED_FEEDS_ADDED, "[]");
+                JSONArray queue = new JSONArray(json);
+                queue.put(downloadUrl);
+                prefs.edit().putString(PREF_QUEUED_FEEDS_ADDED, queue.toString()).apply();
+            } catch (JSONException e) {
+                e.printStackTrace();
+            }
+        }
+        sync(context);
+    }
+
+    public static void enqueueFeedRemoved(Context context, String downloadUrl) {
+        synchronized (lock) {
+            try {
+                SharedPreferences prefs = context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
+                String json = prefs.getString(PREF_QUEUED_FEEDS_REMOVED, "[]");
+                JSONArray queue = new JSONArray(json);
+                queue.put(downloadUrl);
+                prefs.edit().putString(PREF_QUEUED_FEEDS_REMOVED, queue.toString()).apply();
+            } catch (JSONException e) {
+                e.printStackTrace();
+            }
+        }
+        sync(context);
+    }
+
+    public static void enqueueEpisodeAction(Context context, EpisodeAction action) {
+        synchronized (lock) {
+            try {
+                SharedPreferences prefs = context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
+                String json = prefs.getString(PREF_QUEUED_EPISODE_ACTIONS, "[]");
+                JSONArray queue = new JSONArray(json);
+                queue.put(action.writeToJsonObject());
+                prefs.edit().putString(PREF_QUEUED_EPISODE_ACTIONS, queue.toString()).apply();
+            } catch (JSONException e) {
+                e.printStackTrace();
+            }
+        }
+        sync(context);
+    }
+
+    public static void sync(Context context) {
+        OneTimeWorkRequest workRequest = getWorkRequest().build();
+        WorkManager.getInstance().enqueueUniqueWork(WORK_ID_SYNC, ExistingWorkPolicy.REPLACE, workRequest);
+        EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_started));
+    }
+
+    public static void syncImmediately(Context context) {
+        OneTimeWorkRequest workRequest = getWorkRequest()
+                .setInitialDelay(0L, TimeUnit.SECONDS)
+                .build();
+        WorkManager.getInstance().enqueueUniqueWork(WORK_ID_SYNC, ExistingWorkPolicy.REPLACE, workRequest);
+        EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_started));
+    }
+
+    public static void fullSync(Context context) {
+        synchronized (lock) {
+            context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE).edit()
+                    .putLong(PREF_LAST_SUBSCRIPTION_SYNC_TIMESTAMP, 0)
+                    .putLong(PREF_LAST_EPISODE_ACTIONS_SYNC_TIMESTAMP, 0)
+                    .putLong(PREF_LAST_SYNC_ATTEMPT_TIMESTAMP, 0)
+                    .apply();
+        }
+        OneTimeWorkRequest workRequest = getWorkRequest()
+                .setInitialDelay(0L, TimeUnit.SECONDS)
+                .setBackoffCriteria(BackoffPolicy.EXPONENTIAL, 1, TimeUnit.MINUTES)
+                .build();
+        WorkManager.getInstance().enqueueUniqueWork(WORK_ID_SYNC, ExistingWorkPolicy.REPLACE, workRequest);
+        EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_started));
+    }
+
+    private static OneTimeWorkRequest.Builder getWorkRequest() {
+        Constraints.Builder constraints = new Constraints.Builder();
+        if (UserPreferences.isAllowMobileFeedRefresh()) {
+            constraints.setRequiredNetworkType(NetworkType.CONNECTED);
+        } else {
+            constraints.setRequiredNetworkType(NetworkType.UNMETERED);
+        }
+
+        return new OneTimeWorkRequest.Builder(SyncService.class)
+                .setConstraints(constraints.build())
+                .setInitialDelay(5L, TimeUnit.SECONDS); // Give it some time, so other actions can be queued
+    }
+
+    public static boolean isLastSyncSuccessful(Context context) {
+        return context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE)
+                .getBoolean(PREF_LAST_SYNC_ATTEMPT_SUCCESS, false);
+    }
+
+    public static long getLastSyncAttempt(Context context) {
+        return context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE)
+                .getLong(PREF_LAST_SYNC_ATTEMPT_TIMESTAMP, 0);
+    }
+
+    private List<EpisodeAction> getQueuedEpisodeActions() {
+        ArrayList<EpisodeAction> actions = new ArrayList<>();
+        try {
+            SharedPreferences prefs = getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
+            String json = prefs.getString(PREF_QUEUED_EPISODE_ACTIONS, "[]");
+            JSONArray queue = new JSONArray(json);
+            for (int i = 0; i < queue.length(); i++) {
+                actions.add(EpisodeAction.readFromJsonObject(queue.getJSONObject(i)));
+            }
+        } catch (JSONException e) {
+            e.printStackTrace();
+        }
+        return actions;
+    }
+
+    private List<String> getQueuedRemovedFeeds() {
+        ArrayList<String> actions = new ArrayList<>();
+        try {
+            SharedPreferences prefs = getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
+            String json = prefs.getString(PREF_QUEUED_FEEDS_REMOVED, "[]");
+            JSONArray queue = new JSONArray(json);
+            for (int i = 0; i < queue.length(); i++) {
+                actions.add(queue.getString(i));
+            }
+        } catch (JSONException e) {
+            e.printStackTrace();
+        }
+        return actions;
+    }
+
+    private List<String> getQueuedAddedFeeds() {
+        ArrayList<String> actions = new ArrayList<>();
+        try {
+            SharedPreferences prefs = getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
+            String json = prefs.getString(PREF_QUEUED_FEEDS_ADDED, "[]");
+            JSONArray queue = new JSONArray(json);
+            for (int i = 0; i < queue.length(); i++) {
+                actions.add(queue.getString(i));
+            }
+        } catch (JSONException e) {
+            e.printStackTrace();
+        }
+        return actions;
+    }
+
+    private void syncSubscriptions() throws SyncServiceException {
+        final long lastSync = getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE)
+                .getLong(PREF_LAST_SUBSCRIPTION_SYNC_TIMESTAMP, 0);
+        final List<String> localSubscriptions = DBReader.getFeedListDownloadUrls();
+        SubscriptionChanges subscriptionChanges = syncServiceImpl.getSubscriptionChanges(lastSync);
+        long newTimeStamp = subscriptionChanges.getTimestamp();
+
+        List<String> queuedRemovedFeeds = getQueuedRemovedFeeds();
+        List<String> queuedAddedFeeds = getQueuedAddedFeeds();
+
+        Log.d(TAG, "Downloaded subscription changes: " + subscriptionChanges);
+        for (String downloadUrl : subscriptionChanges.getAdded()) {
+            if (!URLChecker.containsUrl(localSubscriptions, downloadUrl) && !queuedRemovedFeeds.contains(downloadUrl)) {
+                Feed feed = new Feed(downloadUrl, null);
+                try {
+                    DownloadRequester.getInstance().downloadFeed(getApplicationContext(), feed);
+                } catch (DownloadRequestException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        // remove subscription if not just subscribed (again)
+        for (String downloadUrl : subscriptionChanges.getRemoved()) {
+            if (!queuedAddedFeeds.contains(downloadUrl)) {
+                DBTasks.removeFeedWithDownloadUrl(getApplicationContext(), downloadUrl);
+            }
+        }
+
+        if (lastSync == 0) {
+            Log.d(TAG, "First sync. Adding all local subscriptions.");
+            queuedAddedFeeds = localSubscriptions;
+            queuedAddedFeeds.removeAll(subscriptionChanges.getAdded());
+            queuedRemovedFeeds.removeAll(subscriptionChanges.getRemoved());
+        }
+
+        if (queuedAddedFeeds.size() > 0 || queuedRemovedFeeds.size() > 0) {
+            Log.d(TAG, "Added: " + StringUtils.join(queuedAddedFeeds, ", "));
+            Log.d(TAG, "Removed: " + StringUtils.join(queuedRemovedFeeds, ", "));
+
+            synchronized (lock) {
+                UploadChangesResponse uploadResponse = syncServiceImpl
+                        .uploadSubscriptionChanges(queuedAddedFeeds, queuedRemovedFeeds);
+                getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE).edit()
+                        .putString(PREF_QUEUED_FEEDS_ADDED, "[]").apply();
+                getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE).edit()
+                        .putString(PREF_QUEUED_FEEDS_REMOVED, "[]").apply();
+                newTimeStamp = uploadResponse.timestamp;
+            }
+        }
+        getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE).edit()
+                .putLong(PREF_LAST_SUBSCRIPTION_SYNC_TIMESTAMP, newTimeStamp).apply();
+    }
+
+    private void syncEpisodeActions() throws SyncServiceException {
+        final long lastSync = getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE)
+                .getLong(PREF_LAST_EPISODE_ACTIONS_SYNC_TIMESTAMP, 0);
+        EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_episodes_download));
+        EpisodeActionChanges getResponse = syncServiceImpl.getEpisodeActionChanges(lastSync);
+        long newTimeStamp = getResponse.getTimestamp();
+        List<EpisodeAction> remoteActions = getResponse.getEpisodeActions();
+        processEpisodeActions(remoteActions);
+
+        // upload local actions
+        EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_episodes_upload));
+        List<EpisodeAction> queuedEpisodeActions = getQueuedEpisodeActions();
+        if (lastSync == 0) {
+            EventBus.getDefault().postSticky(new SyncServiceEvent(R.string.sync_status_upload_played));
+            List<FeedItem> readItems = DBReader.getPlayedItems();
+            Log.d(TAG, "First sync. Upload state for all " + readItems.size() + " played episodes");
+            for (FeedItem item : readItems) {
+                FeedMedia media = item.getMedia();
+                if (media == null) {
+                    continue;
+                }
+                EpisodeAction played = new EpisodeAction.Builder(item, EpisodeAction.PLAY)
+                        .currentTimestamp()
+                        .started(media.getDuration() / 1000)
+                        .position(media.getDuration() / 1000)
+                        .total(media.getDuration() / 1000)
+                        .build();
+                queuedEpisodeActions.add(played);
+            }
+        }
+        if (queuedEpisodeActions.size() > 0) {
+            synchronized (lock) {
+                Log.d(TAG, "Uploading " + queuedEpisodeActions.size() + " actions: "
+                        + StringUtils.join(queuedEpisodeActions, ", "));
+                UploadChangesResponse postResponse = syncServiceImpl.uploadEpisodeActions(queuedEpisodeActions);
+                newTimeStamp = postResponse.timestamp;
+                Log.d(TAG, "Upload episode response: " + postResponse);
+                getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE).edit()
+                        .putString(PREF_QUEUED_EPISODE_ACTIONS, "[]").apply();
+            }
+        }
+        getApplicationContext().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE).edit()
+                .putLong(PREF_LAST_EPISODE_ACTIONS_SYNC_TIMESTAMP, newTimeStamp).apply();
+    }
+
+
+    private synchronized void processEpisodeActions(List<EpisodeAction> remoteActions) {
+        Log.d(TAG, "Processing " + remoteActions.size() + " actions");
+        if (remoteActions.size() == 0) {
+            return;
+        }
+
+        Map<Pair<String, String>, EpisodeAction> localMostRecentPlayAction = new ArrayMap<>();
+        for (EpisodeAction action : getQueuedEpisodeActions()) {
+            Pair<String, String> key = new Pair<>(action.getPodcast(), action.getEpisode());
+            EpisodeAction mostRecent = localMostRecentPlayAction.get(key);
+            if (mostRecent == null || mostRecent.getTimestamp() == null) {
+                localMostRecentPlayAction.put(key, action);
+            } else if (mostRecent.getTimestamp().before(action.getTimestamp())) {
+                localMostRecentPlayAction.put(key, action);
+            }
+        }
+
+        // make sure more recent local actions are not overwritten by older remote actions
+        Map<Pair<String, String>, EpisodeAction> mostRecentPlayAction = new ArrayMap<>();
+        for (EpisodeAction action : remoteActions) {
+            Log.d(TAG, "Processing action: " + action.toString());
+            switch (action.getAction()) {
+                case NEW:
+                    FeedItem newItem = DBReader.getFeedItemByUrl(action.getPodcast(), action.getEpisode());
+                    if (newItem != null) {
+                        DBWriter.markItemPlayed(newItem, FeedItem.UNPLAYED, true);
+                    } else {
+                        Log.i(TAG, "Unknown feed item: " + action);
+                    }
+                    break;
+                case DOWNLOAD:
+                    break;
+                case PLAY:
+                    Pair<String, String> key = new Pair<>(action.getPodcast(), action.getEpisode());
+                    EpisodeAction localMostRecent = localMostRecentPlayAction.get(key);
+                    if (localMostRecent == null || localMostRecent.getTimestamp() == null
+                            || localMostRecent.getTimestamp().before(action.getTimestamp())) {
+                        EpisodeAction mostRecent = mostRecentPlayAction.get(key);
+                        if (mostRecent == null || mostRecent.getTimestamp() == null) {
+                            mostRecentPlayAction.put(key, action);
+                        } else if (action.getTimestamp() != null
+                                && mostRecent.getTimestamp().before(action.getTimestamp())) {
+                            mostRecentPlayAction.put(key, action);
+                        } else {
+                            Log.d(TAG, "No date information in action, skipping it");
+                        }
+                    }
+                    break;
+                case DELETE:
+                    // NEVER EVER call DBWriter.deleteFeedMediaOfItem() here, leads to an infinite loop
+                    break;
+                default:
+                    Log.e(TAG, "Unknown action: " + action);
+                    break;
+            }
+        }
+
+        List<FeedItem> updatedItems = new ArrayList<>();
+        for (EpisodeAction action : mostRecentPlayAction.values()) {
+            FeedItem playItem = DBReader.getFeedItemByUrl(action.getPodcast(), action.getEpisode());
+            Log.d(TAG, "Most recent play action: " + action.toString());
+            if (playItem != null) {
+                FeedMedia media = playItem.getMedia();
+                media.setPosition(action.getPosition() * 1000);
+                if (playItem.getMedia().hasAlmostEnded()) {
+                    Log.d(TAG, "Marking as played");
+                    playItem.setPlayed(true);
+                }
+                updatedItems.add(playItem);
+            }
+        }
+        DBWriter.setItemList(updatedItems);
+    }
+
+    private void clearErrorNotifications() {
+        NotificationManager nm = (NotificationManager) getApplicationContext()
+                .getSystemService(Context.NOTIFICATION_SERVICE);
+        nm.cancel(R.id.notification_gpodnet_sync_error);
+        nm.cancel(R.id.notification_gpodnet_sync_autherror);
+    }
+
+    private void updateErrorNotification(SyncServiceException exception) {
+        Log.d(TAG, "Posting error notification");
+        final String description = getApplicationContext().getString(R.string.gpodnetsync_error_descr)
+                + exception.getMessage();
+
+        Intent intent = getApplicationContext().getPackageManager().getLaunchIntentForPackage(
+                getApplicationContext().getPackageName());
+        PendingIntent pendingIntent = PendingIntent.getActivity(getApplicationContext(), 0, intent,
+                PendingIntent.FLAG_UPDATE_CURRENT);
+        Notification notification = new NotificationCompat.Builder(getApplicationContext(),
+                NotificationUtils.CHANNEL_ID_ERROR)
+                .setContentTitle(getApplicationContext().getString(R.string.gpodnetsync_error_title))
+                .setContentText(description)
+                .setContentIntent(pendingIntent)
+                .setSmallIcon(R.drawable.ic_notification_sync_error)
+                .setAutoCancel(true)
+                .setVisibility(NotificationCompat.VISIBILITY_PUBLIC)
+                .build();
+        NotificationManager nm = (NotificationManager) getApplicationContext()
+                .getSystemService(Context.NOTIFICATION_SERVICE);
+        nm.notify(R.id.notification_gpodnet_sync_error, notification);
+    }
+}

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/GpodnetService.java

@@ -1,7 +1,27 @@
-package de.danoeh.antennapod.core.gpoddernet;
+package de.danoeh.antennapod.core.sync.gpoddernet;
 
+import android.util.Log;
 import androidx.annotation.NonNull;
-
+import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetDevice;
+import de.danoeh.antennapod.core.sync.model.EpisodeAction;
+import de.danoeh.antennapod.core.sync.model.EpisodeActionChanges;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetEpisodeActionPostResponse;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetPodcast;
+import de.danoeh.antennapod.core.sync.model.ISyncService;
+import de.danoeh.antennapod.core.sync.model.SubscriptionChanges;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetTag;
+import de.danoeh.antennapod.core.sync.gpoddernet.model.GpodnetUploadChangesResponse;
+import de.danoeh.antennapod.core.sync.model.SyncServiceException;
+import de.danoeh.antennapod.core.sync.model.UploadChangesResponse;
+import okhttp3.Credentials;
+import okhttp3.MediaType;
+import okhttp3.OkHttpClient;
+import okhttp3.Request;
+import okhttp3.RequestBody;
+import okhttp3.Response;
+import okhttp3.ResponseBody;
+import org.apache.commons.io.Charsets;
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -14,63 +34,43 @@ import java.net.MalformedURLException;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
-import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.LinkedList;
 import java.util.List;
 
-import de.danoeh.antennapod.core.ClientConfig;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetDevice;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeAction;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeActionGetResponse;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetEpisodeActionPostResponse;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetPodcast;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetSubscriptionChange;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetTag;
-import de.danoeh.antennapod.core.gpoddernet.model.GpodnetUploadChangesResponse;
-import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
-import de.danoeh.antennapod.core.service.download.AntennapodHttpClient;
-import okhttp3.Credentials;
-import okhttp3.MediaType;
-import okhttp3.OkHttpClient;
-import okhttp3.Request;
-import okhttp3.RequestBody;
-import okhttp3.Response;
-import okhttp3.ResponseBody;
-
 /**
  * Communicates with the gpodder.net service.
  */
-public class GpodnetService {
+public class GpodnetService implements ISyncService {
-
+    public static final String TAG = "GpodnetService";
-    private static final String TAG = "GpodnetService";
-
-    private static final String BASE_SCHEME = "https";
-
     public static final String DEFAULT_BASE_HOST = "gpodder.net";
-    private final String BASE_HOST;
+    private static final String BASE_SCHEME = "https";
-
+    private static final int UPLOAD_BULK_SIZE = 30;
     private static final MediaType TEXT = MediaType.parse("plain/text; charset=utf-8");
     private static final MediaType JSON = MediaType.parse("application/json; charset=utf-8");
-
+    private final String baseHost;
     private final OkHttpClient httpClient;
+    private String username = null;
 
+    public GpodnetService(OkHttpClient httpClient, String baseHost) {
+        this.httpClient = httpClient;
+        this.baseHost = baseHost;
+    }
 
-    public GpodnetService() {
+    private void requireLoggedIn() {
-        httpClient = AntennapodHttpClient.getHttpClient();
+        if (username == null) {
-        BASE_HOST = GpodnetPreferences.getHostname();
+            throw new IllegalStateException("Not logged in");
+        }
     }
 
     /**
      * Returns the [count] most used tags.
      */
-    public List<GpodnetTag> getTopTags(int count)
+    public List<GpodnetTag> getTopTags(int count) throws GpodnetServiceException {
-            throws GpodnetServiceException {
         URL url;
         try {
-            url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            url = new URI(BASE_SCHEME, baseHost, String.format("/api/2/tags/%d.json", count), null).toURL();
-                    "/api/2/tags/%d.json", count), null).toURL();
         } catch (MalformedURLException | URISyntaxException e) {
             e.printStackTrace();
             throw new GpodnetServiceException(e);
@@ -80,13 +80,12 @@ public class GpodnetService {
         String response = executeRequest(request);
         try {
             JSONArray jsonTagList = new JSONArray(response);
-            List<GpodnetTag> tagList = new ArrayList<>(
+            List<GpodnetTag> tagList = new ArrayList<>(jsonTagList.length());
-                    jsonTagList.length());
             for (int i = 0; i < jsonTagList.length(); i++) {
-                JSONObject jObj = jsonTagList.getJSONObject(i);
+                JSONObject jsonObject = jsonTagList.getJSONObject(i);
-                String title = jObj.getString("title");
+                String title = jsonObject.getString("title");
-                String tag = jObj.getString("tag");
+                String tag = jsonObject.getString("tag");
-                int usage = jObj.getInt("usage");
+                int usage = jsonObject.getInt("usage");
                 tagList.add(new GpodnetTag(title, tag, usage));
             }
             return tagList;
@@ -101,17 +100,16 @@ public class GpodnetService {
      *
      * @throws IllegalArgumentException if tag is null
      */
-    public List<GpodnetPodcast> getPodcastsForTag(@NonNull GpodnetTag tag,
+    public List<GpodnetPodcast> getPodcastsForTag(@NonNull GpodnetTag tag, int count)
-                                                  int count)
             throws GpodnetServiceException {
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format(
                     "/api/2/tag/%s/%d.json", tag.getTag(), count), null).toURL();
             Request.Builder request = new Request.Builder().url(url);
             String response = executeRequest(request);
 
             JSONArray jsonArray = new JSONArray(response);
-            return readPodcastListFromJSONArray(jsonArray);
+            return readPodcastListFromJsonArray(jsonArray);
 
         } catch (JSONException | MalformedURLException | URISyntaxException e) {
             e.printStackTrace();
@@ -125,20 +123,18 @@ public class GpodnetService {
      * @param count of elements that should be returned. Must be in range 1..100.
      * @throws IllegalArgumentException if count is out of range.
      */
-    public List<GpodnetPodcast> getPodcastToplist(int count)
+    public List<GpodnetPodcast> getPodcastToplist(int count) throws GpodnetServiceException {
-            throws GpodnetServiceException {
+        if (count < 1 || count > 100) {
-        if(count < 1 || count > 100) {
             throw new IllegalArgumentException("Count must be in range 1..100");
         }
 
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format("/toplist/%d.json", count), null).toURL();
-                    "/toplist/%d.json", count), null).toURL();
             Request.Builder request = new Request.Builder().url(url);
             String response = executeRequest(request);
 
             JSONArray jsonArray = new JSONArray(response);
-            return readPodcastListFromJSONArray(jsonArray);
+            return readPodcastListFromJsonArray(jsonArray);
 
         } catch (JSONException | MalformedURLException | URISyntaxException e) {
             e.printStackTrace();
@@ -159,18 +155,17 @@ public class GpodnetService {
      * @throws GpodnetServiceAuthenticationException If there is an authentication error.
      */
     public List<GpodnetPodcast> getSuggestions(int count) throws GpodnetServiceException {
-        if(count < 1 || count > 100) {
+        if (count < 1 || count > 100) {
             throw new IllegalArgumentException("Count must be in range 1..100");
         }
 
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format("/suggestions/%d.json", count), null).toURL();
-                    "/suggestions/%d.json", count), null).toURL();
             Request.Builder request = new Request.Builder().url(url);
             String response = executeRequest(request);
 
             JSONArray jsonArray = new JSONArray(response);
-            return readPodcastListFromJSONArray(jsonArray);
+            return readPodcastListFromJsonArray(jsonArray);
         } catch (JSONException | MalformedURLException | URISyntaxException e) {
             e.printStackTrace();
             throw new GpodnetServiceException(e);
@@ -185,19 +180,18 @@ public class GpodnetService {
      *                       Must be in range 1..256. If the value is out of range, the
      *                       default value defined by the gpodder.net API will be used.
      */
-    public List<GpodnetPodcast> searchPodcasts(String query, int scaledLogoSize)
+    public List<GpodnetPodcast> searchPodcasts(String query, int scaledLogoSize) throws GpodnetServiceException {
-            throws GpodnetServiceException {
         String parameters = (scaledLogoSize > 0 && scaledLogoSize <= 256) ? String
                 .format("q=%s&scale_logo=%d", query, scaledLogoSize) : String
                 .format("q=%s", query);
         try {
-            URL url = new URI(BASE_SCHEME, null, BASE_HOST, -1, "/search.json",
+            URL url = new URI(BASE_SCHEME, null, baseHost, -1, "/search.json",
                     parameters, null).toURL();
             Request.Builder request = new Request.Builder().url(url);
             String response = executeRequest(request);
 
             JSONArray jsonArray = new JSONArray(response);
-            return readPodcastListFromJSONArray(jsonArray);
+            return readPodcastListFromJsonArray(jsonArray);
 
         } catch (JSONException | MalformedURLException e) {
             e.printStackTrace();
@@ -213,20 +207,16 @@ public class GpodnetService {
      * <p/>
      * This method requires authentication.
      *
-     * @param username The username. Must be the same user as the one which is
-     *                 currently logged in.
-     * @throws IllegalArgumentException              If username is null.
      * @throws GpodnetServiceAuthenticationException If there is an authentication error.
      */
-    public List<GpodnetDevice> getDevices(@NonNull String username)
+    public List<GpodnetDevice> getDevices() throws GpodnetServiceException {
-            throws GpodnetServiceException {
+        requireLoggedIn();
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format("/api/2/devices/%s.json", username), null).toURL();
-                    "/api/2/devices/%s.json", username), null).toURL();
             Request.Builder request = new Request.Builder().url(url);
             String response = executeRequest(request);
             JSONArray devicesArray = new JSONArray(response);
-            return readDeviceListFromJSONArray(devicesArray);
+            return readDeviceListFromJsonArray(devicesArray);
         } catch (JSONException | MalformedURLException | URISyntaxException e) {
             e.printStackTrace();
             throw new GpodnetServiceException(e);
@@ -238,19 +228,14 @@ public class GpodnetService {
      * <p/>
      * This method requires authentication.
      *
-     * @param username The username. Must be the same user as the one which is
-     *                 currently logged in.
      * @param deviceId The ID of the device that should be configured.
-     * @throws IllegalArgumentException              If username or deviceId is null.
      * @throws GpodnetServiceAuthenticationException If there is an authentication error.
      */
-    public void configureDevice(@NonNull String username,
+    public void configureDevice(@NonNull String deviceId, String caption, GpodnetDevice.DeviceType type)
-                                @NonNull String deviceId,
-                                String caption,
-                                GpodnetDevice.DeviceType type)
             throws GpodnetServiceException {
+        requireLoggedIn();
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format(
                     "/api/2/devices/%s/%s.json", username, deviceId), null).toURL();
             String content;
             if (caption != null || type != null) {
@@ -279,18 +264,14 @@ public class GpodnetService {
      * <p/>
      * This method requires authentication.
      *
-     * @param username The username. Must be the same user as the one which is
-     *                 currently logged in.
      * @param deviceId The ID of the device whose subscriptions should be returned.
      * @return A list of subscriptions in OPML format.
-     * @throws IllegalArgumentException              If username or deviceId is null.
      * @throws GpodnetServiceAuthenticationException If there is an authentication error.
      */
-    public String getSubscriptionsOfDevice(@NonNull String username,
+    public String getSubscriptionsOfDevice(@NonNull String deviceId) throws GpodnetServiceException {
-                                           @NonNull String deviceId)
+        requireLoggedIn();
-            throws GpodnetServiceException {
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format(
                     "/subscriptions/%s/%s.opml", username, deviceId), null).toURL();
             Request.Builder request = new Request.Builder().url(url);
             return executeRequest(request);
@@ -305,18 +286,14 @@ public class GpodnetService {
      * <p/>
      * This method requires authentication.
      *
-     * @param username The username. Must be the same user as the one which is
-     *                 currently logged in.
      * @return A list of subscriptions in OPML format.
      * @throws IllegalArgumentException              If username is null.
      * @throws GpodnetServiceAuthenticationException If there is an authentication error.
      */
-    public String getSubscriptionsOfUser(@NonNull String username)
+    public String getSubscriptionsOfUser() throws GpodnetServiceException {
-            throws GpodnetServiceException {
+        requireLoggedIn();
-
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format("/subscriptions/%s.opml", username), null).toURL();
-                    "/subscriptions/%s.opml", username), null).toURL();
             Request.Builder request = new Request.Builder().url(url);
             return executeRequest(request);
         } catch (MalformedURLException | URISyntaxException e) {
@@ -330,21 +307,17 @@ public class GpodnetService {
      * <p/>
      * This method requires authentication.
      *
-     * @param username      The username. Must be the same user as the one which is
-     *                      currently logged in.
      * @param deviceId      The ID of the device whose subscriptions should be updated.
      * @param subscriptions A list of feed URLs containing all subscriptions of the
      *                      device.
      * @throws IllegalArgumentException              If username, deviceId or subscriptions is null.
      * @throws GpodnetServiceAuthenticationException If there is an authentication error.
      */
-    public void uploadSubscriptions(@NonNull String username,
+    public void uploadSubscriptions(@NonNull String deviceId, @NonNull List<String> subscriptions)
-                                    @NonNull String deviceId,
-                                    @NonNull List<String> subscriptions)
             throws GpodnetServiceException {
-
+        requireLoggedIn();
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format(
                     "/subscriptions/%s/%s.txt", username, deviceId), null).toURL();
             StringBuilder builder = new StringBuilder();
             for (String s : subscriptions) {
@@ -366,25 +339,19 @@ public class GpodnetService {
      * <p/>
      * This method requires authentication.
      *
-     * @param username The username. Must be the same user as the one which is
-     *                 currently logged in.
      * @param deviceId The ID of the device whose subscriptions should be updated.
      * @param added    Collection of feed URLs of added feeds. This Collection MUST NOT contain any duplicates
      * @param removed  Collection of feed URLs of removed feeds. This Collection MUST NOT contain any duplicates
-     * @return a GpodnetUploadChangesResponse. See {@link de.danoeh.antennapod.core.gpoddernet.model.GpodnetUploadChangesResponse}
+     * @return a GpodnetUploadChangesResponse. See {@link GpodnetUploadChangesResponse}
      * for details.
-     * @throws java.lang.IllegalArgumentException                           if username, deviceId, added or removed is null.
+     * @throws GpodnetServiceException            if added or removed contain duplicates or if there
-     * @throws de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException if added or removed contain duplicates or if there
+     *                                            is an authentication error.
-     *                                                                      is an authentication error.
      */
-    public GpodnetUploadChangesResponse uploadChanges(@NonNull String username,
+    public GpodnetUploadChangesResponse uploadChanges(@NonNull String deviceId, @NonNull Collection<String> added,
-                                                      @NonNull String deviceId,
+            @NonNull Collection<String> removed) throws GpodnetServiceException {
-                                                      @NonNull Collection<String> added,
+        requireLoggedIn();
-                                                      @NonNull Collection<String> removed)
-            throws GpodnetServiceException {
-
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            URL url = new URI(BASE_SCHEME, baseHost, String.format(
                     "/api/2/subscriptions/%s/%s.json", username, deviceId), null).toURL();
 
             final JSONObject requestObject = new JSONObject();
@@ -408,30 +375,25 @@ public class GpodnetService {
      * <p/>
      * This method requires authentication.
      *
-     * @param username  The username. Must be the same user as the one which is
-     *                  currently logged in.
      * @param deviceId  The ID of the device whose subscription changes should be
      *                  downloaded.
      * @param timestamp A timestamp that can be used to receive all changes since a
      *                  specific point in time.
-     * @throws IllegalArgumentException              If username or deviceId is null.
      * @throws GpodnetServiceAuthenticationException If there is an authentication error.
      */
-    public GpodnetSubscriptionChange getSubscriptionChanges(@NonNull String username,
+    public SubscriptionChanges getSubscriptionChanges(@NonNull String deviceId, long timestamp)
-                                                            @NonNull String deviceId,
+            throws GpodnetServiceException {
-                                                            long timestamp) throws GpodnetServiceException {
+        requireLoggedIn();
-
         String params = String.format("since=%d", timestamp);
-        String path = String.format("/api/2/subscriptions/%s/%s.json",
+        String path = String.format("/api/2/subscriptions/%s/%s.json", username, deviceId);
-                username, deviceId);
         try {
-            URL url = new URI(BASE_SCHEME, null, BASE_HOST, -1, path, params,
+            URL url = new URI(BASE_SCHEME, null, baseHost, -1, path, params,
                     null).toURL();
             Request.Builder request = new Request.Builder().url(url);
 
             String response = executeRequest(request);
             JSONObject changes = new JSONObject(response);
-            return readSubscriptionChangesFromJSONObject(changes);
+            return readSubscriptionChangesFromJsonObject(changes);
         } catch (URISyntaxException e) {
             e.printStackTrace();
             throw new IllegalStateException(e);
@@ -447,26 +409,36 @@ public class GpodnetService {
      * <p/>
      * This method requires authentication.
      *
-     * @param episodeActions    Collection of episode actions.
+     * @param episodeActions Collection of episode actions.
-     * @return a GpodnetUploadChangesResponse. See {@link de.danoeh.antennapod.core.gpoddernet.model.GpodnetUploadChangesResponse}
+     * @return a GpodnetUploadChangesResponse. See {@link GpodnetUploadChangesResponse}
      * for details.
-     * @throws java.lang.IllegalArgumentException                           if username, deviceId, added or removed is null.
+     * @throws GpodnetServiceException            if added or removed contain duplicates or if there
-     * @throws de.danoeh.antennapod.core.gpoddernet.GpodnetServiceException if added or removed contain duplicates or if there
+     *                                            is an authentication error.
-     *                                                                      is an authentication error.
      */
-    public GpodnetEpisodeActionPostResponse uploadEpisodeActions(@NonNull Collection<GpodnetEpisodeAction> episodeActions)
+    @Override
-            throws GpodnetServiceException {
+    public UploadChangesResponse uploadEpisodeActions(List<EpisodeAction> episodeActions) throws SyncServiceException {
-
+        requireLoggedIn();
-        String username = GpodnetPreferences.getUsername();
+        UploadChangesResponse response = null;
+        for (int i = 0; i < episodeActions.size(); i += UPLOAD_BULK_SIZE) {
+            response = uploadEpisodeActionsPartial(episodeActions,
+                    i, Math.min(episodeActions.size(), i + UPLOAD_BULK_SIZE));
+        }
+        return response;
+    }
 
+    private UploadChangesResponse uploadEpisodeActionsPartial(List<EpisodeAction> episodeActions, int from, int to)
+            throws SyncServiceException {
         try {
-            URL url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            Log.d(TAG, "Uploading partial actions " + from + " to " + to + " of " + episodeActions.size());
+            URL url = new URI(BASE_SCHEME, baseHost, String.format(
                     "/api/2/episodes/%s.json", username), null).toURL();
 
             final JSONArray list = new JSONArray();
-            for(GpodnetEpisodeAction episodeAction : episodeActions) {
+            for (int i = from; i < to; i++) {
-                JSONObject obj = episodeAction.writeToJSONObject();
+                EpisodeAction episodeAction = episodeActions.get(i);
-                if(obj != null) {
+                JSONObject obj = episodeAction.writeToJsonObject();
+                if (obj != null) {
+                    obj.put("device", GpodnetPreferences.getDeviceID());
                     list.put(obj);
                 }
             }
@@ -478,9 +450,8 @@ public class GpodnetService {
             return GpodnetEpisodeActionPostResponse.fromJSONObject(response);
         } catch (JSONException | MalformedURLException | URISyntaxException e) {
             e.printStackTrace();
-            throw new GpodnetServiceException(e);
+            throw new SyncServiceException(e);
         }
-
     }
 
     /**
@@ -490,30 +461,26 @@ public class GpodnetService {
      *
      * @param timestamp A timestamp that can be used to receive all changes since a
      *                  specific point in time.
-     * @throws IllegalArgumentException              If username or deviceId is null.
+     * @throws SyncServiceException If there is an authentication error.
-     * @throws GpodnetServiceAuthenticationException If there is an authentication error.
      */
-    public GpodnetEpisodeActionGetResponse getEpisodeChanges(long timestamp) throws GpodnetServiceException {
+    @Override
-
+    public EpisodeActionChanges getEpisodeActionChanges(long timestamp) throws SyncServiceException {
-        String username = GpodnetPreferences.getUsername();
+        requireLoggedIn();
-
         String params = String.format("since=%d", timestamp);
-        String path = String.format("/api/2/episodes/%s.json",
+        String path = String.format("/api/2/episodes/%s.json", username);
-                username);
         try {
-            URL url = new URI(BASE_SCHEME, null, BASE_HOST, -1, path, params,
+            URL url = new URI(BASE_SCHEME, null, baseHost, -1, path, params, null).toURL();
-                    null).toURL();
             Request.Builder request = new Request.Builder().url(url);
 
             String response = executeRequest(request);
             JSONObject json = new JSONObject(response);
-            return readEpisodeActionsFromJSONObject(json);
+            return readEpisodeActionsFromJsonObject(json);
         } catch (URISyntaxException e) {
             e.printStackTrace();
             throw new IllegalStateException(e);
         } catch (JSONException | MalformedURLException e) {
             e.printStackTrace();
-            throw new GpodnetServiceException(e);
+            throw new SyncServiceException(e);
         }
 
     }
@@ -525,33 +492,27 @@ public class GpodnetService {
      *
      * @throws IllegalArgumentException If username or password is null.
      */
-    public void authenticate(@NonNull String username,
+    public void authenticate(@NonNull String username, @NonNull String password) throws GpodnetServiceException {
-                             @NonNull String password)
-            throws GpodnetServiceException {
         URL url;
         try {
-            url = new URI(BASE_SCHEME, BASE_HOST, String.format(
+            url = new URI(BASE_SCHEME, baseHost, String.format("/api/2/auth/%s/login.json", username), null).toURL();
-                    "/api/2/auth/%s/login.json", username), null).toURL();
         } catch (MalformedURLException | URISyntaxException e) {
             e.printStackTrace();
             throw new GpodnetServiceException(e);
         }
-        RequestBody body = RequestBody.create(TEXT, "");
+        RequestBody requestBody = RequestBody.create(TEXT, "");
-        Request.Builder request = new Request.Builder().url(url).post(body);
+        Request request = new Request.Builder().url(url).post(requestBody).build();
-        executeRequestWithAuthentication(request, username, password);
+        try {
-    }
+            String credential = Credentials.basic(username, password, Charsets.UTF_8);
-
+            Request authRequest = request.newBuilder().header("Authorization", credential).build();
-    /**
+            Response response = httpClient.newCall(authRequest).execute();
-     * Shuts down the GpodnetService's HTTP client. The service will be shut down in a separate thread to avoid
+            checkStatusCode(response);
-     * NetworkOnMainThreadExceptions.
+            response.body().close();
-     */
+            this.username = username;
-    public void shutdown() {
+        } catch (Exception e) {
-        new Thread() {
+            e.printStackTrace();
-            @Override
+            throw new GpodnetServiceException(e);
-            public void run() {
+        }
-                AntennapodHttpClient.cleanup();
-            }
-        }.start();
     }
 
     private String executeRequest(@NonNull Request.Builder requestB) throws GpodnetServiceException {
@@ -576,36 +537,7 @@ public class GpodnetService {
         return responseString;
     }
 
-    private String executeRequestWithAuthentication(Request.Builder requestB,
+    private String getStringFromResponseBody(@NonNull ResponseBody body) throws GpodnetServiceException {
-                                                    String username, String password) throws GpodnetServiceException {
-        if (requestB == null || username == null || password == null) {
-            throw new IllegalArgumentException(
-                    "request and credentials must not be null");
-        }
-
-        Request request = requestB.build();
-        String result = null;
-        ResponseBody body = null;
-        try {
-            String credential = Credentials.basic(username, password, Charset.forName("UTF-8"));
-            Request authRequest = request.newBuilder().header("Authorization", credential).build();
-            Response response = httpClient.newCall(authRequest).execute();
-            checkStatusCode(response);
-            body = response.body();
-            result = getStringFromResponseBody(body);
-        } catch (Exception e) {
-            e.printStackTrace();
-            throw new GpodnetServiceException(e);
-        } finally {
-            if (body != null) {
-                body.close();
-            }
-        }
-        return result;
-    }
-
-    private String getStringFromResponseBody(@NonNull ResponseBody body)
-            throws GpodnetServiceException {
         ByteArrayOutputStream outputStream;
         int contentLength = (int) body.contentLength();
         if (contentLength > 0) {
@@ -627,36 +559,31 @@ public class GpodnetService {
         return outputStream.toString();
     }
 
-    private void checkStatusCode(@NonNull Response response)
+    private void checkStatusCode(@NonNull Response response) throws GpodnetServiceException {
-            throws GpodnetServiceException {
         int responseCode = response.code();
         if (responseCode != HttpURLConnection.HTTP_OK) {
             if (responseCode == HttpURLConnection.HTTP_UNAUTHORIZED) {
                 throw new GpodnetServiceAuthenticationException("Wrong username or password");
             } else {
-                throw new GpodnetServiceBadStatusCodeException("Bad response code: "
+                throw new GpodnetServiceBadStatusCodeException("Bad response code: " + responseCode, responseCode);
-                        + responseCode, responseCode);
             }
         }
     }
 
-    private List<GpodnetPodcast> readPodcastListFromJSONArray(@NonNull JSONArray array)
+    private List<GpodnetPodcast> readPodcastListFromJsonArray(@NonNull JSONArray array) throws JSONException {
-            throws JSONException {
+        List<GpodnetPodcast> result = new ArrayList<>(array.length());
-        List<GpodnetPodcast> result = new ArrayList<>(
-                array.length());
         for (int i = 0; i < array.length(); i++) {
-            result.add(readPodcastFromJSONObject(array.getJSONObject(i)));
+            result.add(readPodcastFromJsonObject(array.getJSONObject(i)));
         }
         return result;
     }
 
-    private GpodnetPodcast readPodcastFromJSONObject(JSONObject object)
+    private GpodnetPodcast readPodcastFromJsonObject(JSONObject object) throws JSONException {
-            throws JSONException {
         String url = object.getString("url");
 
         String title;
         Object titleObj = object.opt("title");
-        if (titleObj != null && titleObj instanceof String) {
+        if (titleObj instanceof String) {
             title = (String) titleObj;
         } else {
             title = url;
@@ -664,7 +591,7 @@ public class GpodnetService {
 
         String description;
         Object descriptionObj = object.opt("description");
-        if (descriptionObj != null && descriptionObj instanceof String) {
+        if (descriptionObj instanceof String) {
             description = (String) descriptionObj;
         } else {
             description = "";
@@ -673,49 +600,38 @@ public class GpodnetService {
         int subscribers = object.getInt("subscribers");
 
         Object logoUrlObj = object.opt("logo_url");
-        String logoUrl = (logoUrlObj instanceof String) ? (String) logoUrlObj
+        String logoUrl = (logoUrlObj instanceof String) ? (String) logoUrlObj : null;
-                : null;
         if (logoUrl == null) {
             Object scaledLogoUrl = object.opt("scaled_logo_url");
-            if (scaledLogoUrl != null && scaledLogoUrl instanceof String) {
+            if (scaledLogoUrl instanceof String) {
                 logoUrl = (String) scaledLogoUrl;
             }
         }
 
         String website = null;
         Object websiteObj = object.opt("website");
-        if (websiteObj != null && websiteObj instanceof String) {
+        if (websiteObj instanceof String) {
             website = (String) websiteObj;
         }
         String mygpoLink = object.getString("mygpo_link");
 
         String author = null;
         Object authorObj = object.opt("author");
-        if (authorObj != null && authorObj instanceof String) {
+        if (authorObj instanceof String) {
             author = (String) authorObj;
         }
-        return new GpodnetPodcast(url,
+        return new GpodnetPodcast(url, title, description, subscribers, logoUrl, website, mygpoLink, author);
-                title,
-                description,
-                subscribers,
-                logoUrl,
-                website,
-                mygpoLink,
-                author);
     }
 
-    private List<GpodnetDevice> readDeviceListFromJSONArray(@NonNull JSONArray array)
+    private List<GpodnetDevice> readDeviceListFromJsonArray(@NonNull JSONArray array) throws JSONException {
-            throws JSONException {
+        List<GpodnetDevice> result = new ArrayList<>(array.length());
-        List<GpodnetDevice> result = new ArrayList<>(
-                array.length());
         for (int i = 0; i < array.length(); i++) {
-            result.add(readDeviceFromJSONObject(array.getJSONObject(i)));
+            result.add(readDeviceFromJsonObject(array.getJSONObject(i)));
         }
         return result;
     }
 
-    private GpodnetDevice readDeviceFromJSONObject(JSONObject object)
+    private GpodnetDevice readDeviceFromJsonObject(JSONObject object) throws JSONException {
-            throws JSONException {
         String id = object.getString("id");
         String caption = object.getString("caption");
         String type = object.getString("type");
@@ -723,8 +639,8 @@ public class GpodnetService {
         return new GpodnetDevice(id, caption, type, subscriptions);
     }
 
-    private GpodnetSubscriptionChange readSubscriptionChangesFromJSONObject(
+    private SubscriptionChanges readSubscriptionChangesFromJsonObject(@NonNull JSONObject object)
-            @NonNull JSONObject object) throws JSONException {
+            throws JSONException {
 
         List<String> added = new LinkedList<>();
         JSONArray jsonAdded = object.getJSONArray("add");
@@ -745,24 +661,44 @@ public class GpodnetService {
         }
 
         long timestamp = object.getLong("timestamp");
-        return new GpodnetSubscriptionChange(added, removed, timestamp);
+        return new SubscriptionChanges(added, removed, timestamp);
     }
 
-    private GpodnetEpisodeActionGetResponse readEpisodeActionsFromJSONObject(
+    private EpisodeActionChanges readEpisodeActionsFromJsonObject(@NonNull JSONObject object)
-            @NonNull JSONObject object) throws JSONException {
+            throws JSONException {
 
-        List<GpodnetEpisodeAction> episodeActions = new ArrayList<>();
+        List<EpisodeAction> episodeActions = new ArrayList<>();
 
         long timestamp = object.getLong("timestamp");
         JSONArray jsonActions = object.getJSONArray("actions");
-        for(int i=0; i < jsonActions.length(); i++) {
+        for (int i = 0; i < jsonActions.length(); i++) {
             JSONObject jsonAction = jsonActions.getJSONObject(i);
-            GpodnetEpisodeAction episodeAction = GpodnetEpisodeAction.readFromJSONObject(jsonAction);
+            EpisodeAction episodeAction = EpisodeAction.readFromJsonObject(jsonAction);
-            if(episodeAction != null) {
+            if (episodeAction != null) {
                 episodeActions.add(episodeAction);
             }
         }
-        return new GpodnetEpisodeActionGetResponse(episodeActions, timestamp);
+        return new EpisodeActionChanges(episodeActions, timestamp);
     }
 
+    @Override
+    public void login() throws GpodnetServiceException {
+        authenticate(GpodnetPreferences.getUsername(), GpodnetPreferences.getPassword());
+    }
+
+    @Override
+    public SubscriptionChanges getSubscriptionChanges(long lastSync) throws GpodnetServiceException {
+        return getSubscriptionChanges(GpodnetPreferences.getDeviceID(), lastSync);
+    }
+
+    @Override
+    public UploadChangesResponse uploadSubscriptionChanges(List<String> addedFeeds, List<String> removedFeeds)
+            throws GpodnetServiceException {
+        return uploadChanges(GpodnetPreferences.getDeviceID(), addedFeeds, removedFeeds);
+    }
+
+    @Override
+    public void logout() {
+
+    }
 }

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/GpodnetServiceAuthenticationException.java

@@ -0,0 +1,9 @@
+package de.danoeh.antennapod.core.sync.gpoddernet;
+
+public class GpodnetServiceAuthenticationException extends GpodnetServiceException {
+    private static final long serialVersionUID = 1L;
+
+    public GpodnetServiceAuthenticationException(String message) {
+        super(message);
+    }
+}

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/GpodnetServiceBadStatusCodeException.java

@@ -1,4 +1,4 @@
-package de.danoeh.antennapod.core.gpoddernet;
+package de.danoeh.antennapod.core.sync.gpoddernet;
 
 class GpodnetServiceBadStatusCodeException extends GpodnetServiceException {
     private static final long serialVersionUID = 1L;

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/GpodnetServiceException.java

@@ -0,0 +1,15 @@
+package de.danoeh.antennapod.core.sync.gpoddernet;
+
+import de.danoeh.antennapod.core.sync.model.SyncServiceException;
+
+public class GpodnetServiceException extends SyncServiceException {
+    private static final long serialVersionUID = 1L;
+
+    public GpodnetServiceException(String message) {
+        super(message);
+    }
+
+    public GpodnetServiceException(Throwable e) {
+        super(e);
+    }
+}

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/model/GpodnetDevice.java

@@ -1,4 +1,4 @@
-package de.danoeh.antennapod.core.gpoddernet.model;
+package de.danoeh.antennapod.core.sync.gpoddernet.model;
 
 import androidx.annotation.NonNull;
 

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/model/GpodnetEpisodeActionPostResponse.java

@@ -1,7 +1,8 @@
-package de.danoeh.antennapod.core.gpoddernet.model;
+package de.danoeh.antennapod.core.sync.gpoddernet.model;
 
 import androidx.collection.ArrayMap;
 
+import de.danoeh.antennapod.core.sync.model.UploadChangesResponse;
 import org.apache.commons.lang3.builder.ToStringBuilder;
 import org.apache.commons.lang3.builder.ToStringStyle;
 import org.json.JSONArray;
@@ -10,13 +11,7 @@ import org.json.JSONObject;
 
 import java.util.Map;
 
-public class GpodnetEpisodeActionPostResponse {
+public class GpodnetEpisodeActionPostResponse extends UploadChangesResponse {
-
-    /**
-     * timestamp/ID that can be used for requesting changes since this upload.
-     */
-    public final long timestamp;
-
     /**
      * URLs that should be updated. The key of the map is the original URL, the value of the map
      * is the sanitized URL.
@@ -24,7 +19,7 @@ public class GpodnetEpisodeActionPostResponse {
     private final Map<String, String> updatedUrls;
 
     private GpodnetEpisodeActionPostResponse(long timestamp, Map<String, String> updatedUrls) {
-        this.timestamp = timestamp;
+        super(timestamp);
         this.updatedUrls = updatedUrls;
     }
 

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/model/GpodnetPodcast.java

@@ -1,4 +1,4 @@
-package de.danoeh.antennapod.core.gpoddernet.model;
+package de.danoeh.antennapod.core.sync.gpoddernet.model;
 
 import androidx.annotation.NonNull;
 

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/model/GpodnetTag.java

@@ -1,4 +1,4 @@
-package de.danoeh.antennapod.core.gpoddernet.model;
+package de.danoeh.antennapod.core.sync.gpoddernet.model;
 
 import android.os.Parcel;
 import android.os.Parcelable;

core/src/main/java/de/danoeh/antennapod/core/sync/gpoddernet/model/GpodnetUploadChangesResponse.java

@@ -1,7 +1,9 @@
-package de.danoeh.antennapod.core.gpoddernet.model;
+package de.danoeh.antennapod.core.sync.gpoddernet.model;
 
 import androidx.collection.ArrayMap;
 
+import de.danoeh.antennapod.core.sync.gpoddernet.GpodnetService;
+import de.danoeh.antennapod.core.sync.model.UploadChangesResponse;
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -9,23 +11,17 @@ import org.json.JSONObject;
 import java.util.Map;
 
 /**
- * Object returned by {@link de.danoeh.antennapod.core.gpoddernet.GpodnetService} in uploadChanges method.
+ * Object returned by {@link GpodnetService} in uploadChanges method.
  */
-public class GpodnetUploadChangesResponse {
+public class GpodnetUploadChangesResponse extends UploadChangesResponse {
-
-    /**
-     * timestamp/ID that can be used for requesting changes since this upload.
-     */
-    public final long timestamp;
-
     /**
      * URLs that should be updated. The key of the map is the original URL, the value of the map
      * is the sanitized URL.
      */
-    private final Map<String, String> updatedUrls;
+    public final Map<String, String> updatedUrls;
 
-    private GpodnetUploadChangesResponse(long timestamp, Map<String, String> updatedUrls) {
+    public GpodnetUploadChangesResponse(long timestamp, Map<String, String> updatedUrls) {
-        this.timestamp = timestamp;
+        super(timestamp);
         this.updatedUrls = updatedUrls;
     }
 

core/src/main/java/de/danoeh/antennapod/core/sync/model/EpisodeAction.java

@@ -1,9 +1,11 @@
-package de.danoeh.antennapod.core.gpoddernet.model;
+package de.danoeh.antennapod.core.sync.model;
-
 
 import android.text.TextUtils;
 import android.util.Log;
 
+import androidx.core.util.ObjectsCompat;
+import de.danoeh.antennapod.core.feed.FeedItem;
+import de.danoeh.antennapod.core.util.DateUtils;
 import org.json.JSONException;
 import org.json.JSONObject;
 
@@ -12,104 +14,65 @@ import java.util.Date;
 import java.util.Locale;
 import java.util.TimeZone;
 
-import de.danoeh.antennapod.core.feed.FeedItem;
+public class EpisodeAction {
-import de.danoeh.antennapod.core.preferences.GpodnetPreferences;
+    private static final String TAG = "EpisodeAction";
-import de.danoeh.antennapod.core.util.DateUtils;
+    public static final Action NEW = Action.NEW;
-
+    public static final Action DOWNLOAD = Action.DOWNLOAD;
-public class GpodnetEpisodeAction {
+    public static final Action PLAY = Action.PLAY;
-
+    public static final Action DELETE = Action.DELETE;
-    private static final String TAG = "GpodnetEpisodeAction";
-
-    public enum Action {
-        NEW, DOWNLOAD, PLAY, DELETE
-    }
 
     private final String podcast;
     private final String episode;
-    private final String deviceId;
     private final Action action;
     private final Date timestamp;
     private final int started;
     private final int position;
     private final int total;
 
-    private GpodnetEpisodeAction(Builder builder) {
+    private EpisodeAction(Builder builder) {
         this.podcast = builder.podcast;
         this.episode = builder.episode;
         this.action = builder.action;
-        this.deviceId = builder.deviceId;
         this.timestamp = builder.timestamp;
         this.started = builder.started;
         this.position = builder.position;
         this.total = builder.total;
     }
 
-    /**
-     * Creates an episode action object from a String representation. The representation includes
-     * all mandatory and optional attributes
-     *
-     * @param s String representation (output from {@link #writeToString()})
-     * @return episode action object, or null if s is invalid
-     */
-    public static GpodnetEpisodeAction readFromString(String s) {
-        String[] fields = s.split("\t");
-        if(fields.length != 8) {
-            return null;
-        }
-        String podcast = fields[0];
-        String episode = fields[1];
-        String deviceId = fields[2];
-        try {
-            Action action = Action.valueOf(fields[3]);
-            return new Builder(podcast, episode, action)
-                    .deviceId(deviceId)
-                    .timestamp(new Date(Long.parseLong(fields[4])))
-                    .started(Integer.parseInt(fields[5]))
-                    .position(Integer.parseInt(fields[6]))
-                    .total(Integer.parseInt(fields[7]))
-                    .build();
-        } catch(IllegalArgumentException e) {
-            Log.e(TAG, "readFromString(" + s + "): " + e.getMessage());
-            return null;
-        }
-    }
-
     /**
      * Create an episode action object from JSON representation. Mandatory fields are "podcast",
      * "episode" and "action".
      *
-     *  @param object JSON representation
+     * @param object JSON representation
-     *  @return episode action object, or null if mandatory values are missing
+     * @return episode action object, or null if mandatory values are missing
      */
-    public static GpodnetEpisodeAction readFromJSONObject(JSONObject object) {
+    public static EpisodeAction readFromJsonObject(JSONObject object) {
         String podcast = object.optString("podcast", null);
         String episode = object.optString("episode", null);
         String actionString = object.optString("action", null);
-        if(TextUtils.isEmpty(podcast) || TextUtils.isEmpty(episode) || TextUtils.isEmpty(actionString)) {
+        if (TextUtils.isEmpty(podcast) || TextUtils.isEmpty(episode) || TextUtils.isEmpty(actionString)) {
             return null;
         }
-        GpodnetEpisodeAction.Action action;
+        EpisodeAction.Action action;
         try {
-            action = GpodnetEpisodeAction.Action.valueOf(actionString.toUpperCase());
+            action = EpisodeAction.Action.valueOf(actionString.toUpperCase());
         } catch (IllegalArgumentException e) {
             return null;
         }
-        String deviceId = object.optString("device", "");
+        EpisodeAction.Builder builder = new EpisodeAction.Builder(podcast, episode, action);
-        GpodnetEpisodeAction.Builder builder = new GpodnetEpisodeAction.Builder(podcast, episode, action)
-                .deviceId(deviceId);
         String utcTimestamp = object.optString("timestamp", null);
-        if(!TextUtils.isEmpty(utcTimestamp)) {
+        if (!TextUtils.isEmpty(utcTimestamp)) {
             builder.timestamp(DateUtils.parse(utcTimestamp));
         }
-        if(action == GpodnetEpisodeAction.Action.PLAY) {
+        if (action == EpisodeAction.Action.PLAY) {
             int started = object.optInt("started", -1);
             int position = object.optInt("position", -1);
             int total = object.optInt("total", -1);
-            if(started >= 0 && position > 0 && total > 0) {
+            if (started >= 0 && position > 0 && total > 0) {
                 builder
-                    .started(started)
+                        .started(started)
-                    .position(position)
+                        .position(position)
-                    .total(total);
+                        .total(total);
             }
         }
         return builder.build();
@@ -123,10 +86,6 @@ public class GpodnetEpisodeAction {
         return this.episode;
     }
 
-    public String getDeviceId() {
-        return this.deviceId;
-    }
-
     public Action getAction() {
         return this.action;
     }
@@ -140,7 +99,7 @@ public class GpodnetEpisodeAction {
     }
 
     /**
-     * Returns the position (in seconds) at which the client started playback
+     * Returns the position (in seconds) at which the client started playback.
      *
      * @return start position (in seconds)
      */
@@ -149,7 +108,7 @@ public class GpodnetEpisodeAction {
     }
 
     /**
-     * Returns the position (in seconds) at which the client stopped playback
+     * Returns the position (in seconds) at which the client stopped playback.
      *
      * @return stop position (in seconds)
      */
@@ -168,28 +127,24 @@ public class GpodnetEpisodeAction {
 
     @Override
     public boolean equals(Object o) {
-        if (this == o) return true;
+        if (this == o) {
-        if (o == null || !(o instanceof GpodnetEpisodeAction)) return false;
+            return true;
-
+        }
-        GpodnetEpisodeAction that = (GpodnetEpisodeAction) o;
+        if (!(o instanceof EpisodeAction)) {
-
-        if (started != that.started) return false;
-        if (position != that.position) return false;
-        if (total != that.total) return false;
-        if (podcast != null ? !podcast.equals(that.podcast) : that.podcast != null) return false;
-        if (episode != null ? !episode.equals(that.episode) : that.episode != null) return false;
-        if (deviceId != null ? !deviceId.equals(that.deviceId) : that.deviceId != null)
             return false;
-        if (action != that.action) return false;
+        }
-        return !(timestamp != null ? !timestamp.equals(that.timestamp) : that.timestamp != null);
 
+        EpisodeAction that = (EpisodeAction) o;
+        return started == that.started && position == that.position && total == that.total && action != that.action
+                && ObjectsCompat.equals(podcast, that.podcast)
+                && ObjectsCompat.equals(episode, that.episode)
+                && ObjectsCompat.equals(timestamp, that.timestamp);
     }
 
     @Override
     public int hashCode() {
         int result = podcast != null ? podcast.hashCode() : 0;
         result = 31 * result + (episode != null ? episode.hashCode() : 0);
-        result = 31 * result + (deviceId != null ? deviceId.hashCode() : 0);
         result = 31 * result + (action != null ? action.hashCode() : 0);
         result = 31 * result + (timestamp != null ? timestamp.hashCode() : 0);
         result = 31 * result + started;
@@ -198,38 +153,26 @@ public class GpodnetEpisodeAction {
         return result;
     }
 
-    public String writeToString() {
-        return this.podcast + "\t"
-                + this.episode + "\t"
-                + this.deviceId + "\t"
-                + this.action + "\t"
-                + this.timestamp.getTime() + "\t"
-                + this.started + "\t"
-                + this.position + "\t"
-                + this.total;
-    }
-
     /**
-     * Returns a JSON object representation of this object
+     * Returns a JSON object representation of this object.
      *
      * @return JSON object representation, or null if the object is invalid
      */
-    public JSONObject writeToJSONObject() {
+    public JSONObject writeToJsonObject() {
         JSONObject obj = new JSONObject();
         try {
             obj.putOpt("podcast", this.podcast);
             obj.putOpt("episode", this.episode);
-            obj.put("device", this.deviceId);
             obj.put("action", this.getActionString());
             SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss", Locale.US);
             formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
-            obj.put("timestamp",formatter.format(this.timestamp));
+            obj.put("timestamp", formatter.format(this.timestamp));
             if (this.getAction() == Action.PLAY) {
                 obj.put("started", this.started);
                 obj.put("position", this.position);
                 obj.put("total", this.total);
             }
-        } catch(JSONException e) {
+        } catch (JSONException e) {
             Log.e(TAG, "writeToJSONObject(): " + e.getMessage());
             return null;
         }
@@ -238,16 +181,19 @@ public class GpodnetEpisodeAction {
 
     @Override
     public String toString() {
-        return "GpodnetEpisodeAction{" +
+        return "EpisodeAction{"
-                "podcast='" + podcast + '\'' +
+                + "podcast='" + podcast + '\''
-                ", episode='" + episode + '\'' +
+                + ", episode='" + episode + '\''
-                ", deviceId='" + deviceId + '\'' +
+                + ", action=" + action
-                ", action=" + action +
+                + ", timestamp=" + timestamp
-                ", timestamp=" + timestamp +
+                + ", started=" + started
-                ", started=" + started +
+                + ", position=" + position
-                ", position=" + position +
+                + ", total=" + total
-                ", total=" + total +
+                + '}';
-                '}';
+    }
+
+    public enum Action {
+        NEW, DOWNLOAD, PLAY, DELETE
     }
 
     public static class Builder {
@@ -258,7 +204,6 @@ public class GpodnetEpisodeAction {
         private final Action action;
 
         // optional
-        private String deviceId = "";
         private Date timestamp;
         private int started = -1;
         private int position = -1;
@@ -274,15 +219,6 @@ public class GpodnetEpisodeAction {
             this.action = action;
         }
 
-        public Builder deviceId(String deviceId) {
-            this.deviceId = deviceId;
-            return this;
-        }
-
-        public Builder currentDeviceId() {
-            return deviceId(GpodnetPreferences.getDeviceID());
-        }
-
         public Builder timestamp(Date timestamp) {
             this.timestamp = timestamp;
             return this;
@@ -293,28 +229,28 @@ public class GpodnetEpisodeAction {
         }
 
         public Builder started(int seconds) {
-            if(action == Action.PLAY) {
+            if (action == Action.PLAY) {
                 this.started = seconds;
             }
             return this;
         }
 
         public Builder position(int seconds) {
-            if(action == Action.PLAY) {
+            if (action == Action.PLAY) {
                 this.position = seconds;
             }
             return this;
         }
 
         public Builder total(int seconds) {
-            if(action == Action.PLAY) {
+            if (action == Action.PLAY) {
                 this.total = seconds;
             }
             return this;
         }
 
-        public GpodnetEpisodeAction build() {
+        public EpisodeAction build() {
-            return new GpodnetEpisodeAction(this);
+            return new EpisodeAction(this);
         }
 
     }

core/src/main/java/de/danoeh/antennapod/core/sync/model/EpisodeActionChanges.java

@@ -0,0 +1,33 @@
+package de.danoeh.antennapod.core.sync.model;
+
+
+import androidx.annotation.NonNull;
+
+import java.util.List;
+
+public class EpisodeActionChanges {
+
+    private final List<EpisodeAction> episodeActions;
+    private final long timestamp;
+
+    public EpisodeActionChanges(@NonNull List<EpisodeAction> episodeActions, long timestamp) {
+        this.episodeActions = episodeActions;
+        this.timestamp = timestamp;
+    }
+
+    public List<EpisodeAction> getEpisodeActions() {
+        return this.episodeActions;
+    }
+
+    public long getTimestamp() {
+        return this.timestamp;
+    }
+
+    @Override
+    public String toString() {
+        return "EpisodeActionGetResponse{"
+                + "episodeActions=" + episodeActions
+                + ", timestamp=" + timestamp
+                + '}';
+    }
+}

core/src/main/java/de/danoeh/antennapod/core/sync/model/ISyncService.java

@@ -0,0 +1,20 @@
+package de.danoeh.antennapod.core.sync.model;
+
+import java.util.List;
+
+public interface ISyncService {
+
+    void login() throws SyncServiceException;
+
+    SubscriptionChanges getSubscriptionChanges(long lastSync) throws SyncServiceException;
+
+    UploadChangesResponse uploadSubscriptionChanges(
+            List<String> addedFeeds, List<String> removedFeeds) throws SyncServiceException;
+
+    EpisodeActionChanges getEpisodeActionChanges(long lastSync) throws SyncServiceException;
+
+    UploadChangesResponse uploadEpisodeActions(List<EpisodeAction> queuedEpisodeActions)
+            throws SyncServiceException;
+
+    void logout() throws SyncServiceException;
+}

core/src/main/java/de/danoeh/antennapod/core/sync/model/SubscriptionChanges.java

@@ -1,17 +1,17 @@
-package de.danoeh.antennapod.core.gpoddernet.model;
+package de.danoeh.antennapod.core.sync.model;
 
 import androidx.annotation.NonNull;
 
 import java.util.List;
 
-public class GpodnetSubscriptionChange {
+public class SubscriptionChanges {
     private final List<String> added;
     private final List<String> removed;
     private final long timestamp;
 
-    public GpodnetSubscriptionChange(@NonNull List<String> added,
+    public SubscriptionChanges(@NonNull List<String> added,
-                                     @NonNull List<String> removed,
+                               @NonNull List<String> removed,
-                                     long timestamp) {
+                               long timestamp) {
         this.added = added;
         this.removed = removed;
         this.timestamp = timestamp;
@@ -19,7 +19,7 @@ public class GpodnetSubscriptionChange {
 
     @Override
     public String toString() {
-        return "GpodnetSubscriptionChange [added=" + added.toString()
+        return "SubscriptionChange [added=" + added.toString()
                 + ", removed=" + removed.toString() + ", timestamp="
                 + timestamp + "]";
     }

core/src/main/java/de/danoeh/antennapod/core/sync/model/SyncServiceException.java

@@ -0,0 +1,13 @@
+package de.danoeh.antennapod.core.sync.model;
+
+public class SyncServiceException extends Exception {
+    private static final long serialVersionUID = 1L;
+
+    public SyncServiceException(String message) {
+        super(message);
+    }
+
+    public SyncServiceException(Throwable cause) {
+        super(cause);
+    }
+}

core/src/main/java/de/danoeh/antennapod/core/sync/model/UploadChangesResponse.java

@@ -0,0 +1,13 @@
+package de.danoeh.antennapod.core.sync.model;
+
+public abstract class UploadChangesResponse {
+
+    /**
+     * timestamp/ID that can be used for requesting changes since this upload.
+     */
+    public final long timestamp;
+
+    public UploadChangesResponse(long timestamp) {
+        this.timestamp = timestamp;
+    }
+}

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

@@ -437,12 +437,10 @@
     <string name="pref_gpodnet_logout_toast">Logout was successful</string>
     <string name="pref_gpodnet_setlogin_information_title">Change login information</string>
     <string name="pref_gpodnet_setlogin_information_sum">Change the login information for your gpodder.net account.</string>
-    <string name="pref_gpodnet_sync_changes_title">Sync changes now</string>
+    <string name="pref_gpodnet_sync_changes_title">Synchronize now</string>
     <string name="pref_gpodnet_sync_changes_sum">Sync subscription and episode state changes with gpodder.net.</string>
-    <string name="pref_gpodnet_full_sync_title">Full sync now</string>
+    <string name="pref_gpodnet_full_sync_title">Force full synchronization</string>
     <string name="pref_gpodnet_full_sync_sum">Sync all subscriptions and episode states with gpodder.net.</string>
-    <string name="pref_gpodnet_sync_sum_last_sync_line">Last sync attempt: %1$s (%2$s)</string>
-    <string name="pref_gpodnet_sync_started">Sync started</string>
     <string name="pref_gpodnet_login_status"><![CDATA[Logged in as <i>%1$s</i> with device <i>%2$s</i>]]></string>
     <string name="pref_gpodnet_notifications_title">Show sync error notifications</string>
     <string name="pref_gpodnet_notifications_sum">This setting does not apply to authentication errors.</string>
@@ -536,6 +534,15 @@
     <string name="search_label">Search</string>
     <string name="no_results_for_query">No results were found for \"%1$s\"</string>
 
+    <!-- Synchronization -->
+    <string name="sync_status_started">Sync started</string>
+    <string name="sync_status_episodes_upload">Uploading episode changes…</string>
+    <string name="sync_status_episodes_download">Downloading episode changes…</string>
+    <string name="sync_status_upload_played">Uploading played status…</string>
+    <string name="sync_status_subscriptions">Synchronizing subscriptions…</string>
+    <string name="sync_status_success">Synchronization successful</string>
+    <string name="sync_status_error">Synchronization failed</string>
+
     <!-- import and export -->
     <string name="import_export_summary">Move subscriptions and queue to another device</string>
     <string name="database">Database</string>

core/src/play/java/de/danoeh/antennapod/core/ClientConfig.java

@@ -39,8 +39,6 @@ public class ClientConfig {
 
     public static PlaybackServiceCallbacks playbackServiceCallbacks;
 
-    public static GpodnetCallbacks gpodnetCallbacks;
-
     public static DBTasksCallbacks dbTasksCallbacks;
 
     public static CastCallbacks castCallbacks;

core/src/play/java/de/danoeh/antennapod/core/cast/CastUtils.java

@@ -206,7 +206,7 @@ public class CastUtils {
                 }
             }
             if (result == null) {
-                FeedItem feedItem = DBReader.getFeedItem(metadata.getString(KEY_FEED_URL),
+                FeedItem feedItem = DBReader.getFeedItemByUrl(metadata.getString(KEY_FEED_URL),
                         metadata.getString(KEY_EPISODE_IDENTIFIER));
                 if (feedItem != null) {
                     result = feedItem.getMedia();

settings.gradle

@@ -1,2 +1 @@
-include ':app'
+include ':app', ':sync', ':core'
-include ':core'