Remove subscribed podcasts from discover / suggestions (#6269)

3 files changed, 99 insertions, 77 deletions

diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/DiscoveryFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/DiscoveryFragment.java
index 88b9ac8f1..16ccb2af4 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/DiscoveryFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/DiscoveryFragment.java
@@ -14,17 +14,25 @@ import android.widget.Button;
 import android.widget.GridView;
 import android.widget.ProgressBar;
 import android.widget.TextView;
-
 import androidx.annotation.NonNull;
 import androidx.appcompat.widget.Toolbar;
 import androidx.fragment.app.Fragment;
-
 import com.google.android.material.appbar.MaterialToolbar;
 import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import com.google.android.material.textfield.MaterialAutoCompleteTextView;
 import com.google.android.material.textfield.TextInputLayout;
-
+import de.danoeh.antennapod.R;
+import de.danoeh.antennapod.activity.OnlineFeedViewActivity;
+import de.danoeh.antennapod.adapter.itunes.ItunesAdapter;
 import de.danoeh.antennapod.core.BuildConfig;
+import de.danoeh.antennapod.core.storage.DBReader;
+import de.danoeh.antennapod.event.DiscoveryDefaultUpdateEvent;
+import de.danoeh.antennapod.net.discovery.ItunesTopListLoader;
+import de.danoeh.antennapod.net.discovery.PodcastSearchResult;
+import io.reactivex.Observable;
+import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.disposables.Disposable;
+import io.reactivex.schedulers.Schedulers;
 import org.greenrobot.eventbus.EventBus;
 
 import java.util.ArrayList;
@@ -35,20 +43,13 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 
-import de.danoeh.antennapod.R;
-import de.danoeh.antennapod.activity.OnlineFeedViewActivity;
-import de.danoeh.antennapod.adapter.itunes.ItunesAdapter;
-import de.danoeh.antennapod.event.DiscoveryDefaultUpdateEvent;
-import de.danoeh.antennapod.net.discovery.ItunesTopListLoader;
-import de.danoeh.antennapod.net.discovery.PodcastSearchResult;
-import io.reactivex.disposables.Disposable;
-
 /**
  * Searches iTunes store for top podcasts and displays results in a list.
  */
 public class DiscoveryFragment extends Fragment implements Toolbar.OnMenuItemClickListener {
 
     private static final String TAG = "ItunesSearchFragment";
+    private static final int NUM_OF_TOP_PODCASTS = 25;
     private SharedPreferences prefs;
 
     /**
@@ -188,19 +189,23 @@ public class DiscoveryFragment extends Fragment implements Toolbar.OnMenuItemCli
         }
 
         ItunesTopListLoader loader = new ItunesTopListLoader(getContext());
-        disposable = loader.loadToplist(country, 25).subscribe(
-                podcasts -> {
-                    progressBar.setVisibility(View.GONE);
-                    topList = podcasts;
-                    updateData(topList);
-                }, error -> {
-                    Log.e(TAG, Log.getStackTraceString(error));
-                    progressBar.setVisibility(View.GONE);
-                    txtvError.setText(error.getMessage());
-                    txtvError.setVisibility(View.VISIBLE);
-                    butRetry.setOnClickListener(v -> loadToplist(country));
-                    butRetry.setVisibility(View.VISIBLE);
-                });
+        disposable = Observable.fromCallable(() ->
+                        loader.loadToplist(country, NUM_OF_TOP_PODCASTS, DBReader.getFeedList()))
+                .subscribeOn(Schedulers.io())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(
+                    podcasts -> {
+                        progressBar.setVisibility(View.GONE);
+                        topList = podcasts;
+                        updateData(topList);
+                    }, error -> {
+                        Log.e(TAG, Log.getStackTraceString(error));
+                        progressBar.setVisibility(View.GONE);
+                        txtvError.setText(error.getMessage());
+                        txtvError.setVisibility(View.VISIBLE);
+                        butRetry.setOnClickListener(v -> loadToplist(country));
+                        butRetry.setVisibility(View.VISIBLE);
+                    });
     }
 
     @Override
diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/QuickFeedDiscoveryFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/QuickFeedDiscoveryFragment.java
index acdd1e1c7..d5192061c 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/QuickFeedDiscoveryFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/QuickFeedDiscoveryFragment.java
@@ -5,7 +5,6 @@ import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.text.TextUtils;
 import android.util.DisplayMetrics;
-import androidx.fragment.app.Fragment;
 
 import android.util.Log;
 import android.view.LayoutInflater;
@@ -16,20 +15,23 @@ import android.widget.Button;
 import android.widget.GridView;
 import android.widget.LinearLayout;
 import android.widget.TextView;
-
+import androidx.fragment.app.Fragment;
 import de.danoeh.antennapod.BuildConfig;
-import de.danoeh.antennapod.net.discovery.ItunesTopListLoader;
-import de.danoeh.antennapod.net.discovery.PodcastSearchResult;
-import org.greenrobot.eventbus.EventBus;
-import org.greenrobot.eventbus.Subscribe;
-import org.greenrobot.eventbus.ThreadMode;
-
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.activity.MainActivity;
 import de.danoeh.antennapod.activity.OnlineFeedViewActivity;
 import de.danoeh.antennapod.adapter.FeedDiscoverAdapter;
+import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.event.DiscoveryDefaultUpdateEvent;
+import de.danoeh.antennapod.net.discovery.ItunesTopListLoader;
+import de.danoeh.antennapod.net.discovery.PodcastSearchResult;
+import io.reactivex.Observable;
+import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.disposables.Disposable;
+import io.reactivex.schedulers.Schedulers;
+import org.greenrobot.eventbus.EventBus;
+import org.greenrobot.eventbus.Subscribe;
+import org.greenrobot.eventbus.ThreadMode;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -138,26 +140,29 @@ public class QuickFeedDiscoveryFragment extends Fragment implements AdapterView.
             return;
         }
 
-        disposable = loader.loadToplist(countryCode, NUM_SUGGESTIONS)
+        disposable = Observable.fromCallable(() ->
+                        loader.loadToplist(countryCode, NUM_SUGGESTIONS, DBReader.getFeedList()))
+                .subscribeOn(Schedulers.io())
+                .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(
-                        podcasts -> {
-                            errorView.setVisibility(View.GONE);
-                            if (podcasts.size() == 0) {
-                                errorTextView.setText(getResources().getText(R.string.search_status_no_results));
-                                errorView.setVisibility(View.VISIBLE);
-                                discoverGridLayout.setVisibility(View.INVISIBLE);
-                            } else {
-                                discoverGridLayout.setVisibility(View.VISIBLE);
-                                adapter.updateData(podcasts);
-                            }
-                        }, error -> {
-                            Log.e(TAG, Log.getStackTraceString(error));
-                            errorTextView.setText(error.getLocalizedMessage());
+                    podcasts -> {
+                        errorView.setVisibility(View.GONE);
+                        if (podcasts.size() == 0) {
+                            errorTextView.setText(getResources().getText(R.string.search_status_no_results));
                             errorView.setVisibility(View.VISIBLE);
                             discoverGridLayout.setVisibility(View.INVISIBLE);
-                            errorRetry.setVisibility(View.VISIBLE);
-                            errorRetry.setOnClickListener((listener) -> loadToplist());
-                        });
+                        } else {
+                            discoverGridLayout.setVisibility(View.VISIBLE);
+                            adapter.updateData(podcasts);
+                        }
+                    }, error -> {
+                        Log.e(TAG, Log.getStackTraceString(error));
+                        errorTextView.setText(error.getLocalizedMessage());
+                        errorView.setVisibility(View.VISIBLE);
+                        discoverGridLayout.setVisibility(View.INVISIBLE);
+                        errorRetry.setVisibility(View.VISIBLE);
+                        errorRetry.setOnClickListener(v -> loadToplist());
+                    });
     }
 
     @Override
diff --git a/net/discovery/src/main/java/de/danoeh/antennapod/net/discovery/ItunesTopListLoader.java b/net/discovery/src/main/java/de/danoeh/antennapod/net/discovery/ItunesTopListLoader.java
index 53ea00235..0bfc5a863 100644
--- a/net/discovery/src/main/java/de/danoeh/antennapod/net/discovery/ItunesTopListLoader.java
+++ b/net/discovery/src/main/java/de/danoeh/antennapod/net/discovery/ItunesTopListLoader.java
@@ -2,12 +2,8 @@ package de.danoeh.antennapod.net.discovery;
 
 import android.content.Context;
 import android.util.Log;
-
 import de.danoeh.antennapod.core.service.download.AntennapodHttpClient;
-import io.reactivex.Single;
-import io.reactivex.SingleOnSubscribe;
-import io.reactivex.android.schedulers.AndroidSchedulers;
-import io.reactivex.schedulers.Schedulers;
+import de.danoeh.antennapod.model.feed.Feed;
 import okhttp3.CacheControl;
 import okhttp3.OkHttpClient;
 import okhttp3.Request;
@@ -18,8 +14,10 @@ import org.json.JSONObject;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Locale;
+import java.util.Set;
 import java.util.concurrent.TimeUnit;
 
 public class ItunesTopListLoader {
@@ -30,39 +28,53 @@ public class ItunesTopListLoader {
     public static final String PREF_KEY_NEEDS_CONFIRM = "needs_confirm";
     public static final String PREFS = "CountryRegionPrefs";
     public static final String COUNTRY_CODE_UNSET = "99";
+    private static final int NUM_LOADED = 25;
 
     public ItunesTopListLoader(Context context) {
         this.context = context;
     }
 
-    public Single<List<PodcastSearchResult>> loadToplist(String country, int limit) {
-        return Single.create((SingleOnSubscribe<List<PodcastSearchResult>>) emitter -> {
-            OkHttpClient client = AntennapodHttpClient.getHttpClient();
-            String feedString;
-            String loadCountry = country;
+    public List<PodcastSearchResult> loadToplist(String country, int limit, List<Feed> subscribed)
+            throws JSONException, IOException {
+        OkHttpClient client = AntennapodHttpClient.getHttpClient();
+        String feedString;
+        String loadCountry = country;
+        if (COUNTRY_CODE_UNSET.equals(country)) {
+            loadCountry = Locale.getDefault().getCountry();
+        }
+        try {
+            feedString = getTopListFeed(client, loadCountry);
+        } catch (IOException e) {
             if (COUNTRY_CODE_UNSET.equals(country)) {
-                loadCountry = Locale.getDefault().getCountry();
-            }
-            try {
-                feedString = getTopListFeed(client, loadCountry, limit);
-            } catch (IOException e) {
-                if (COUNTRY_CODE_UNSET.equals(country)) {
-                    feedString = getTopListFeed(client, "US", limit);
-                } else {
-                    emitter.onError(e);
-                    return;
-                }
+                feedString = getTopListFeed(client, "US");
+            } else {
+                throw e;
             }
+        }
+        return removeSubscribed(parseFeed(feedString), subscribed, limit);
+    }
 
-            List<PodcastSearchResult> podcasts = parseFeed(feedString);
-            emitter.onSuccess(podcasts);
-        })
-                .subscribeOn(Schedulers.io())
-                .observeOn(AndroidSchedulers.mainThread());
+    private static List<PodcastSearchResult> removeSubscribed(
+            List<PodcastSearchResult> suggestedPodcasts, List<Feed> subscribedFeeds, int limit) {
+        Set<String> subscribedPodcastsSet = new HashSet<>();
+        for (Feed subscribedFeed : subscribedFeeds) {
+            String subscribedTitle = subscribedFeed.getTitle().trim() + " - " + subscribedFeed.getAuthor().trim();
+            subscribedPodcastsSet.add(subscribedTitle);
+        }
+        List<PodcastSearchResult> suggestedNotSubscribed = new ArrayList<>();
+        for (PodcastSearchResult suggested : suggestedPodcasts) {
+            if (!subscribedPodcastsSet.contains(suggested.title.trim())) {
+                suggestedNotSubscribed.add(suggested);
+            }
+            if (suggestedNotSubscribed.size() == limit) {
+                return suggestedNotSubscribed;
+            }
+        }
+        return suggestedNotSubscribed;
     }
 
-    private String getTopListFeed(OkHttpClient client, String country, int limit) throws IOException {
-        String url = "https://itunes.apple.com/%s/rss/toppodcasts/limit=" + limit + "/explicit=true/json";
+    private String getTopListFeed(OkHttpClient client, String country) throws IOException {
+        String url = "https://itunes.apple.com/%s/rss/toppodcasts/limit=" + NUM_LOADED + "/explicit=true/json";
         Log.d(TAG, "Feed URL " + String.format(url, country));
         Request.Builder httpReq = new Request.Builder()
                 .cacheControl(new CacheControl.Builder().maxStale(1, TimeUnit.DAYS).build())