Fix stupid Redgifs API issue.

47 files changed, 6193 insertions, 118 deletions

diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/AppModule.java b/app/src/main/java/ml/docilealligator/infinityforreddit/AppModule.java
index 78e475b8..3f5f51fd 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/AppModule.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/AppModule.java
@@ -20,15 +20,15 @@ import javax.inject.Singleton;
 
 import dagger.Module;
 import dagger.Provides;
-import im.ene.toro.exoplayer.Config;
-import im.ene.toro.exoplayer.ExoCreator;
-import im.ene.toro.exoplayer.MediaSourceBuilder;
-import im.ene.toro.exoplayer.ToroExo;
 import ml.docilealligator.infinityforreddit.customtheme.CustomThemeWrapper;
 import ml.docilealligator.infinityforreddit.customviews.LoopAvailableExoCreator;
 import ml.docilealligator.infinityforreddit.utils.APIUtils;
 import ml.docilealligator.infinityforreddit.utils.CustomThemeSharedPreferencesUtils;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
+import ml.docilealligator.infinityforreddit.videoautoplay.Config;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoCreator;
+import ml.docilealligator.infinityforreddit.videoautoplay.MediaSourceBuilder;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroExo;
 import okhttp3.ConnectionPool;
 import okhttp3.OkHttpClient;
 import retrofit2.Retrofit;
@@ -119,9 +119,24 @@ class AppModule {
     @Provides
     @Named("redgifs")
     @Singleton
-    Retrofit provideRedgifsRetrofit() {
+    Retrofit provideRedgifsRetrofit(@Named("current_account") SharedPreferences currentAccountSharedPreferences) {
+        OkHttpClient.Builder okHttpClientBuilder = new OkHttpClient.Builder();
+        okHttpClientBuilder
+                .addInterceptor(chain -> chain.proceed(
+                        chain.request()
+                                .newBuilder()
+                                .header("User-Agent", APIUtils.getRedgifsUserAgent(mApplication))
+                                .build()
+                ))
+                .addInterceptor(new RedgifsAccessTokenAuthenticator(currentAccountSharedPreferences))
+                .connectTimeout(30, TimeUnit.SECONDS)
+                .readTimeout(30, TimeUnit.SECONDS)
+                .writeTimeout(30, TimeUnit.SECONDS)
+                .connectionPool(new ConnectionPool(0, 1, TimeUnit.NANOSECONDS));
+
         return new Retrofit.Builder()
                 .baseUrl(APIUtils.REDGIFS_API_BASE_URI)
+                .client(okHttpClientBuilder.build())
                 .addConverterFactory(ScalarsConverterFactory.create())
                 .build();
     }
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/FetchGfycatOrRedgifsVideoLinks.java b/app/src/main/java/ml/docilealligator/infinityforreddit/FetchGfycatOrRedgifsVideoLinks.java
index 8040d466..d1bfd941 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/FetchGfycatOrRedgifsVideoLinks.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/FetchGfycatOrRedgifsVideoLinks.java
@@ -1,5 +1,7 @@
 package ml.docilealligator.infinityforreddit;
 
+import android.content.Context;
+import android.content.SharedPreferences;
 import android.os.Handler;
 
 import org.json.JSONException;
@@ -9,7 +11,10 @@ import java.io.IOException;
 import java.util.concurrent.Executor;
 
 import ml.docilealligator.infinityforreddit.apis.GfycatAPI;
+import ml.docilealligator.infinityforreddit.apis.RedgifsAPI;
+import ml.docilealligator.infinityforreddit.utils.APIUtils;
 import ml.docilealligator.infinityforreddit.utils.JSONUtils;
+import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
 import retrofit2.Call;
 import retrofit2.Response;
 import retrofit2.Retrofit;
@@ -21,18 +26,14 @@ public class FetchGfycatOrRedgifsVideoLinks {
         void failed(int errorCode);
     }
 
-    public static void fetchGfycatOrRedgifsVideoLinks(Executor executor, Handler handler, Retrofit gfycatRetrofit,
-                                                      String gfycatId, boolean isGfycatVideo,
-                                                      FetchGfycatOrRedgifsVideoLinksListener fetchGfycatOrRedgifsVideoLinksListener) {
+    public static void fetchGfycatVideoLinks(Executor executor, Handler handler, Retrofit gfycatRetrofit,
+                                             String gfycatId,
+                                             FetchGfycatOrRedgifsVideoLinksListener fetchGfycatOrRedgifsVideoLinksListener) {
         executor.execute(() -> {
             try {
                 Response<String> response = gfycatRetrofit.create(GfycatAPI.class).getGfycatData(gfycatId).execute();
                 if (response.isSuccessful()) {
-                    if (isGfycatVideo) {
-                        parseGfycatVideoLinks(handler, response.body(), fetchGfycatOrRedgifsVideoLinksListener);
-                    } else {
-                        parseRedgifsVideoLinks(handler, response.body(), fetchGfycatOrRedgifsVideoLinksListener);
-                    }
+                    parseGfycatVideoLinks(handler, response.body(), fetchGfycatOrRedgifsVideoLinksListener);
                 } else {
                     handler.post(() -> fetchGfycatOrRedgifsVideoLinksListener.failed(response.code()));
                 }
@@ -41,12 +42,31 @@ public class FetchGfycatOrRedgifsVideoLinks {
                 handler.post(() -> fetchGfycatOrRedgifsVideoLinksListener.failed(-1));
             }
         });
+    }
 
+    public static void fetchRedgifsVideoLinks(Context context, Executor executor, Handler handler, Retrofit redgifsRetrofit,
+                                              SharedPreferences currentAccountSharedPreferences,
+                                              String gfycatId,
+                                              FetchGfycatOrRedgifsVideoLinksListener fetchGfycatOrRedgifsVideoLinksListener) {
+        executor.execute(() -> {
+            try {
+                Response<String> response = redgifsRetrofit.create(RedgifsAPI.class).getRedgifsData(APIUtils.getRedgifsOAuthHeader(currentAccountSharedPreferences.getString(SharedPreferencesUtils.REDGIFS_ACCESS_TOKEN, "")),
+                         gfycatId, APIUtils.getRedgifsUserAgent(context)).execute();
+                if (response.isSuccessful()) {
+                    parseRedgifsVideoLinks(handler, response.body(), fetchGfycatOrRedgifsVideoLinksListener);
+                } else {
+                    handler.post(() -> fetchGfycatOrRedgifsVideoLinksListener.failed(response.code()));
+                }
+            } catch (IOException e) {
+                e.printStackTrace();
+                handler.post(() -> fetchGfycatOrRedgifsVideoLinksListener.failed(-1));
+            }
+        });
     }
 
     public static void fetchGfycatOrRedgifsVideoLinksInRecyclerViewAdapter(Executor executor, Handler handler,
                                                                            Call<String> gfycatCall,
-                                                                           String gfycatId, boolean isGfycatVideo,
+                                                                           boolean isGfycatVideo,
                                                                            boolean automaticallyTryRedgifs,
                                                                            FetchGfycatOrRedgifsVideoLinksListener fetchGfycatOrRedgifsVideoLinksListener) {
         executor.execute(() -> {
@@ -61,7 +81,7 @@ public class FetchGfycatOrRedgifsVideoLinks {
                 } else {
                     if (response.code() == 404 && isGfycatVideo && automaticallyTryRedgifs) {
                         fetchGfycatOrRedgifsVideoLinksInRecyclerViewAdapter(executor, handler, gfycatCall.clone(),
-                                gfycatId, false, false, fetchGfycatOrRedgifsVideoLinksListener);
+                                false, false, fetchGfycatOrRedgifsVideoLinksListener);
                     } else {
                         handler.post(() -> fetchGfycatOrRedgifsVideoLinksListener.failed(response.code()));
                     }
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/RedgifsAccessTokenAuthenticator.java b/app/src/main/java/ml/docilealligator/infinityforreddit/RedgifsAccessTokenAuthenticator.java
new file mode 100644
index 00000000..a4feec43
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/RedgifsAccessTokenAuthenticator.java
@@ -0,0 +1,90 @@
+package ml.docilealligator.infinityforreddit;
+
+import android.content.SharedPreferences;
+import android.util.Log;
+
+import androidx.annotation.NonNull;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+import ml.docilealligator.infinityforreddit.apis.RedgifsAPI;
+import ml.docilealligator.infinityforreddit.utils.APIUtils;
+import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
+import okhttp3.Headers;
+import okhttp3.Interceptor;
+import okhttp3.Response;
+import retrofit2.Call;
+import retrofit2.Retrofit;
+import retrofit2.converter.scalars.ScalarsConverterFactory;
+
+public class RedgifsAccessTokenAuthenticator implements Interceptor {
+    private SharedPreferences mCurrentAccountSharedPreferences;
+
+    public RedgifsAccessTokenAuthenticator(SharedPreferences currentAccountSharedPreferences) {
+        this.mCurrentAccountSharedPreferences = currentAccountSharedPreferences;
+    }
+
+    private String refreshAccessToken() {
+        Retrofit retrofit = new Retrofit.Builder()
+                .baseUrl(APIUtils.REDGIFS_API_BASE_URI)
+                .addConverterFactory(ScalarsConverterFactory.create())
+                .build();
+        RedgifsAPI api = retrofit.create(RedgifsAPI.class);
+
+        Map<String, String> params = new HashMap<>();
+        params.put(APIUtils.GRANT_TYPE_KEY, APIUtils.GRANT_TYPE_CLIENT_CREDENTIALS);
+        params.put(APIUtils.CLIENT_ID_KEY, APIUtils.REDGIFS_CLIENT_ID);
+        params.put(APIUtils.CLIENT_SECRET_KEY, APIUtils.REDGIFS_CLIENT_SECRET);
+
+        Call<String> accessTokenCall = api.getRedgifsAccessToken(params);
+        try {
+            retrofit2.Response<String> response = accessTokenCall.execute();
+            if (response.isSuccessful() && response.body() != null) {
+                String newAccessToken = new JSONObject(response.body()).getString(APIUtils.ACCESS_TOKEN_KEY);
+                mCurrentAccountSharedPreferences.edit().putString(SharedPreferencesUtils.REDGIFS_ACCESS_TOKEN, newAccessToken).apply();
+
+                return newAccessToken;
+            }
+            return "";
+        } catch (IOException | JSONException e) {
+            e.printStackTrace();
+        }
+
+        return "";
+    }
+
+    @NonNull
+    @Override
+    public Response intercept(@NonNull Chain chain) throws IOException {
+        Response response = chain.proceed(chain.request());
+        if (response.code() == 401 || response.code() == 400) {
+            String accessTokenHeader = response.request().header(APIUtils.AUTHORIZATION_KEY);
+            if (accessTokenHeader == null) {
+                return response;
+            }
+
+            String accessToken = accessTokenHeader.substring(APIUtils.AUTHORIZATION_BASE.length() - 1).trim();
+            synchronized (this) {
+                String accessTokenFromSharedPreferences = mCurrentAccountSharedPreferences.getString(SharedPreferencesUtils.REDGIFS_ACCESS_TOKEN, "");
+                if (accessToken.equals(accessTokenFromSharedPreferences)) {
+                    String newAccessToken = refreshAccessToken();
+                    if (!newAccessToken.equals("")) {
+                        response.close();
+                        return chain.proceed(response.request().newBuilder().headers(Headers.of(APIUtils.getRedgifsOAuthHeader(newAccessToken))).build());
+                    } else {
+                        return response;
+                    }
+                } else {
+                    response.close();
+                    return chain.proceed(response.request().newBuilder().headers(Headers.of(APIUtils.getRedgifsOAuthHeader(accessTokenFromSharedPreferences))).build());
+                }
+            }
+        }
+        return response;
+    }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/activities/ViewVideoActivity.java b/app/src/main/java/ml/docilealligator/infinityforreddit/activities/ViewVideoActivity.java
index 434390fb..2fab98e7 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/activities/ViewVideoActivity.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/activities/ViewVideoActivity.java
@@ -65,7 +65,6 @@ import com.google.android.exoplayer2.upstream.DefaultHttpDataSourceFactory;
 import com.google.android.exoplayer2.upstream.cache.CacheDataSourceFactory;
 import com.google.android.exoplayer2.upstream.cache.SimpleCache;
 import com.google.android.exoplayer2.util.MimeTypes;
-import com.google.android.exoplayer2.util.Util;
 import com.google.android.exoplayer2.video.VideoListener;
 import com.google.android.material.bottomappbar.BottomAppBar;
 import com.google.android.material.snackbar.Snackbar;
@@ -104,6 +103,7 @@ import ml.docilealligator.infinityforreddit.post.FetchPost;
 import ml.docilealligator.infinityforreddit.post.Post;
 import ml.docilealligator.infinityforreddit.services.DownloadMediaService;
 import ml.docilealligator.infinityforreddit.services.DownloadRedditVideoService;
+import ml.docilealligator.infinityforreddit.utils.APIUtils;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
 import ml.docilealligator.infinityforreddit.utils.Utils;
 import retrofit2.Call;
@@ -221,6 +221,10 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
     SharedPreferences mSharedPreferences;
 
     @Inject
+    @Named("current_account")
+    SharedPreferences mCurrentAccountSharedPreferences;
+
+    @Inject
     CustomThemeWrapper mCustomThemeWrapper;
 
     @Inject
@@ -503,8 +507,7 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
                 loadStreamableVideo(shortCode, savedInstanceState);
             } else {
                 dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
-                        new DefaultDataSourceFactory(ViewVideoActivity.this,
-                                Util.getUserAgent(ViewVideoActivity.this, "Infinity")));
+                        new DefaultDataSourceFactory(ViewVideoActivity.this, APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
                 player.prepare(new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
                 preparePlayer(savedInstanceState);
             }
@@ -535,8 +538,7 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
                 }
             } else {
                 dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
-                        new DefaultDataSourceFactory(ViewVideoActivity.this,
-                        Util.getUserAgent(ViewVideoActivity.this, "Infinity")));
+                        new DefaultDataSourceFactory(ViewVideoActivity.this, APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
                 player.prepare(new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
                 preparePlayer(savedInstanceState);
             }
@@ -549,7 +551,7 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
             }
             // Produces DataSource instances through which media data is loaded.
             dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
-                    new DefaultHttpDataSourceFactory(Util.getUserAgent(this, "Infinity")));
+                    new DefaultHttpDataSourceFactory(APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
             // Prepare the player with the source.
             player.prepare(new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
             preparePlayer(savedInstanceState);
@@ -560,7 +562,7 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
             videoFileName = subredditName + "-" + id + ".mp4";
             // Produces DataSource instances through which media data is loaded.
             dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
-                    new DefaultHttpDataSourceFactory(Util.getUserAgent(this, "Infinity")));
+                    new DefaultHttpDataSourceFactory(APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
             // Prepare the player with the source.
             player.prepare(new HlsMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
             preparePlayer(savedInstanceState);
@@ -678,24 +680,22 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
     private void loadGfycatOrRedgifsVideo(Retrofit retrofit, String gfycatId, boolean isGfycatVideo,
                                           Bundle savedInstanceState, boolean needErrorHandling) {
         progressBar.setVisibility(View.VISIBLE);
-        FetchGfycatOrRedgifsVideoLinks.fetchGfycatOrRedgifsVideoLinks(mExecutor, new Handler(), retrofit, gfycatId,
-                isGfycatVideo, new FetchGfycatOrRedgifsVideoLinks.FetchGfycatOrRedgifsVideoLinksListener() {
-                    @Override
-                    public void success(String webm, String mp4) {
-                        progressBar.setVisibility(View.GONE);
-                        mVideoUri = Uri.parse(webm);
-                        videoDownloadUrl = mp4;
-                        dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
-                                new DefaultDataSourceFactory(ViewVideoActivity.this,
-                                Util.getUserAgent(ViewVideoActivity.this, "Infinity")));
-                        preparePlayer(savedInstanceState);
-                        player.prepare(new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
-                    }
+        if (isGfycatVideo) {
+            FetchGfycatOrRedgifsVideoLinks.fetchGfycatVideoLinks(mExecutor, new Handler(), retrofit, gfycatId,
+                    new FetchGfycatOrRedgifsVideoLinks.FetchGfycatOrRedgifsVideoLinksListener() {
+                        @Override
+                        public void success(String webm, String mp4) {
+                            progressBar.setVisibility(View.GONE);
+                            mVideoUri = Uri.parse(webm);
+                            videoDownloadUrl = mp4;
+                            dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
+                                    new DefaultDataSourceFactory(ViewVideoActivity.this, APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
+                            preparePlayer(savedInstanceState);
+                            player.prepare(new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
+                        }
 
-                    @Override
-                    public void failed(int errorCode) {
-                        progressBar.setVisibility(View.GONE);
-                        if (videoType == VIDEO_TYPE_GFYCAT) {
+                        @Override
+                        public void failed(int errorCode) {
                             if (errorCode == 404 && needErrorHandling) {
                                 if (mSharedPreferences.getBoolean(SharedPreferencesUtils.AUTOMATICALLY_TRY_REDGIFS, true)) {
                                     loadGfycatOrRedgifsVideo(redgifsRetrofit, gfycatId, false, savedInstanceState, false);
@@ -704,13 +704,32 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
                                             view -> loadGfycatOrRedgifsVideo(redgifsRetrofit, gfycatId, false, savedInstanceState, false)).show();
                                 }
                             } else {
+                                progressBar.setVisibility(View.GONE);
                                 Toast.makeText(ViewVideoActivity.this, R.string.fetch_gfycat_video_failed, Toast.LENGTH_SHORT).show();
                             }
-                        } else {
+                        }
+                    });
+        } else {
+            FetchGfycatOrRedgifsVideoLinks.fetchRedgifsVideoLinks(this, mExecutor, new Handler(), redgifsRetrofit,
+                    mCurrentAccountSharedPreferences, gfycatId, new FetchGfycatOrRedgifsVideoLinks.FetchGfycatOrRedgifsVideoLinksListener() {
+                        @Override
+                        public void success(String webm, String mp4) {
+                            progressBar.setVisibility(View.GONE);
+                            mVideoUri = Uri.parse(webm);
+                            videoDownloadUrl = mp4;
+                            dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
+                                    new DefaultDataSourceFactory(ViewVideoActivity.this, APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
+                            preparePlayer(savedInstanceState);
+                            player.prepare(new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
+                        }
+
+                        @Override
+                        public void failed(int errorCode) {
+                            progressBar.setVisibility(View.GONE);
                             Toast.makeText(ViewVideoActivity.this, R.string.fetch_redgifs_video_failed, Toast.LENGTH_SHORT).show();
                         }
-                    }
-                });
+                    });
+        }
     }
 
     private void loadVReddItVideo(Bundle savedInstanceState) {
@@ -764,7 +783,7 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
                                         videoFileName = "imgur-" + FilenameUtils.getName(videoDownloadUrl);
                                         // Produces DataSource instances through which media data is loaded.
                                         dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
-                                                new DefaultHttpDataSourceFactory(Util.getUserAgent(ViewVideoActivity.this, "Infinity")));
+                                                new DefaultHttpDataSourceFactory(APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
                                         // Prepare the player with the source.
                                         player.prepare(new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
                                         preparePlayer(savedInstanceState);
@@ -779,9 +798,7 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
                                             videoFileName = subredditName + "-" + id + ".mp4";
                                             // Produces DataSource instances through which media data is loaded.
                                             dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
-                                                    new DefaultHttpDataSourceFactory(
-                                                            Util.getUserAgent(ViewVideoActivity.this,
-                                                                    "Infinity")));
+                                                    new DefaultHttpDataSourceFactory(APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
                                             // Prepare the player with the source.
                                             preparePlayer(savedInstanceState);
                                             player.prepare(new HlsMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
@@ -823,8 +840,7 @@ public class ViewVideoActivity extends AppCompatActivity implements CustomFontRe
                         videoDownloadUrl = streamableVideo.mp4 == null ? streamableVideo.mp4Mobile.url : streamableVideo.mp4.url;
                         mVideoUri = Uri.parse(videoDownloadUrl);
                         dataSourceFactory = new CacheDataSourceFactory(mSimpleCache,
-                                new DefaultDataSourceFactory(ViewVideoActivity.this,
-                                        Util.getUserAgent(ViewVideoActivity.this, "Infinity")));
+                                new DefaultDataSourceFactory(ViewVideoActivity.this, APIUtils.getRedgifsUserAgent(ViewVideoActivity.this)));
                         preparePlayer(savedInstanceState);
                         player.prepare(new ProgressiveMediaSource.Factory(dataSourceFactory).createMediaSource(mVideoUri));
                     }
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/HistoryPostRecyclerViewAdapter.java b/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/HistoryPostRecyclerViewAdapter.java
index 201e7930..2eba5f0c 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/HistoryPostRecyclerViewAdapter.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/HistoryPostRecyclerViewAdapter.java
@@ -56,14 +56,6 @@ import java.util.concurrent.Executor;
 
 import butterknife.BindView;
 import butterknife.ButterKnife;
-import im.ene.toro.CacheManager;
-import im.ene.toro.ToroPlayer;
-import im.ene.toro.ToroUtil;
-import im.ene.toro.exoplayer.ExoCreator;
-import im.ene.toro.exoplayer.ExoPlayerViewHelper;
-import im.ene.toro.exoplayer.Playable;
-import im.ene.toro.media.PlaybackInfo;
-import im.ene.toro.widget.Container;
 import jp.wasabeef.glide.transformations.BlurTransformation;
 import jp.wasabeef.glide.transformations.RoundedCornersTransformation;
 import ml.docilealligator.infinityforreddit.FetchGfycatOrRedgifsVideoLinks;
@@ -83,18 +75,26 @@ import ml.docilealligator.infinityforreddit.activities.ViewSubredditDetailActivi
 import ml.docilealligator.infinityforreddit.activities.ViewUserDetailActivity;
 import ml.docilealligator.infinityforreddit.activities.ViewVideoActivity;
 import ml.docilealligator.infinityforreddit.apis.GfycatAPI;
+import ml.docilealligator.infinityforreddit.apis.RedgifsAPI;
 import ml.docilealligator.infinityforreddit.apis.StreamableAPI;
 import ml.docilealligator.infinityforreddit.bottomsheetfragments.ShareLinkBottomSheetFragment;
 import ml.docilealligator.infinityforreddit.customtheme.CustomThemeWrapper;
 import ml.docilealligator.infinityforreddit.customviews.AspectRatioGifImageView;
 import ml.docilealligator.infinityforreddit.events.PostUpdateEventToPostDetailFragment;
 import ml.docilealligator.infinityforreddit.fragments.HistoryPostFragment;
-import ml.docilealligator.infinityforreddit.fragments.PostFragment;
 import ml.docilealligator.infinityforreddit.post.Post;
 import ml.docilealligator.infinityforreddit.post.PostPagingSource;
 import ml.docilealligator.infinityforreddit.utils.APIUtils;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
 import ml.docilealligator.infinityforreddit.utils.Utils;
+import ml.docilealligator.infinityforreddit.videoautoplay.CacheManager;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoCreator;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoPlayerViewHelper;
+import ml.docilealligator.infinityforreddit.videoautoplay.Playable;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
 import pl.droidsonroids.gif.GifImageView;
 import retrofit2.Call;
 import retrofit2.Retrofit;
@@ -124,6 +124,7 @@ public class HistoryPostRecyclerViewAdapter extends PagingDataAdapter<Post, Recy
     private BaseActivity mActivity;
     private HistoryPostFragment mFragment;
     private SharedPreferences mSharedPreferences;
+    private SharedPreferences mCurrentAccountSharedPreferences;
     private Executor mExecutor;
     private Retrofit mOauthRetrofit;
     private Retrofit mGfycatRetrofit;
@@ -209,14 +210,15 @@ public class HistoryPostRecyclerViewAdapter extends PagingDataAdapter<Post, Recy
                                           Retrofit gfycatRetrofit, Retrofit redgifsRetrofit, Retrofit streambleRetrofit,
                                           CustomThemeWrapper customThemeWrapper, Locale locale,
                                           String accessToken, String accountName, int postType, int postLayout, boolean displaySubredditName,
-                                          SharedPreferences sharedPreferences, SharedPreferences nsfwAndSpoilerSharedPreferences,
-                                          SharedPreferences postHistorySharedPreferences,
+                                          SharedPreferences sharedPreferences, SharedPreferences currentAccountSharedPreferences,
+                                          SharedPreferences nsfwAndSpoilerSharedPreferences,
                                           ExoCreator exoCreator, Callback callback) {
         super(DIFF_CALLBACK);
         if (activity != null) {
             mActivity = activity;
             mFragment = fragment;
             mSharedPreferences = sharedPreferences;
+            mCurrentAccountSharedPreferences = currentAccountSharedPreferences;
             mExecutor = executor;
             mOauthRetrofit = oauthRetrofit;
             mGfycatRetrofit = gfycatRetrofit;
@@ -676,9 +678,10 @@ public class HistoryPostRecyclerViewAdapter extends PagingDataAdapter<Post, Recy
 
                     if ((post.isGfycat() || post.isRedgifs()) && !post.isLoadGfycatOrStreamableVideoSuccess()) {
                         ((PostVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall =
-                                (post.isGfycat() ? mGfycatRetrofit : mRedgifsRetrofit).create(GfycatAPI.class).getGfycatData(post.getGfycatId());
+                                post.isGfycat() ? mGfycatRetrofit.create(GfycatAPI.class).getGfycatData(post.getGfycatId()) :
+                                        mRedgifsRetrofit.create(RedgifsAPI.class).getRedgifsData(APIUtils.getRedgifsOAuthHeader(mCurrentAccountSharedPreferences.getString(SharedPreferencesUtils.REDGIFS_ACCESS_TOKEN, "")), post.getGfycatId(), APIUtils.getRedgifsUserAgent(mActivity));
                         FetchGfycatOrRedgifsVideoLinks.fetchGfycatOrRedgifsVideoLinksInRecyclerViewAdapter(mExecutor, new Handler(),
-                                ((PostVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall, post.getGfycatId(),
+                                ((PostVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall,
                                 post.isGfycat(), mAutomaticallyTryRedgifs,
                                 new FetchGfycatOrRedgifsVideoLinks.FetchGfycatOrRedgifsVideoLinksListener() {
                                     @Override
@@ -837,9 +840,10 @@ public class HistoryPostRecyclerViewAdapter extends PagingDataAdapter<Post, Recy
 
                     if ((post.isGfycat() || post.isRedgifs()) && !post.isLoadGfycatOrStreamableVideoSuccess()) {
                         ((PostCard2VideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall =
-                                (post.isGfycat() ? mGfycatRetrofit : mRedgifsRetrofit).create(GfycatAPI.class).getGfycatData(post.getGfycatId());
+                                post.isGfycat() ? mGfycatRetrofit.create(GfycatAPI.class).getGfycatData(post.getGfycatId()) :
+                                        mRedgifsRetrofit.create(RedgifsAPI.class).getRedgifsData(APIUtils.getRedgifsOAuthHeader(mCurrentAccountSharedPreferences.getString(SharedPreferencesUtils.REDGIFS_ACCESS_TOKEN, "")), post.getGfycatId(), APIUtils.getRedgifsUserAgent(mActivity));
                         FetchGfycatOrRedgifsVideoLinks.fetchGfycatOrRedgifsVideoLinksInRecyclerViewAdapter(mExecutor, new Handler(),
-                                ((PostCard2VideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall, post.getGfycatId(),
+                                ((PostCard2VideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall,
                                 post.isGfycat(), mAutomaticallyTryRedgifs,
                                 new FetchGfycatOrRedgifsVideoLinks.FetchGfycatOrRedgifsVideoLinksListener() {
                                     @Override
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/PostDetailRecyclerViewAdapter.java b/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/PostDetailRecyclerViewAdapter.java
index c4a119ee..4db8166f 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/PostDetailRecyclerViewAdapter.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/PostDetailRecyclerViewAdapter.java
@@ -54,14 +54,6 @@ import java.util.concurrent.Executor;
 
 import butterknife.BindView;
 import butterknife.ButterKnife;
-import im.ene.toro.CacheManager;
-import im.ene.toro.ToroPlayer;
-import im.ene.toro.ToroUtil;
-import im.ene.toro.exoplayer.ExoCreator;
-import im.ene.toro.exoplayer.ExoPlayerViewHelper;
-import im.ene.toro.exoplayer.Playable;
-import im.ene.toro.media.PlaybackInfo;
-import im.ene.toro.widget.Container;
 import io.noties.markwon.AbstractMarkwonPlugin;
 import io.noties.markwon.Markwon;
 import io.noties.markwon.MarkwonConfiguration;
@@ -100,6 +92,7 @@ import ml.docilealligator.infinityforreddit.activities.ViewSubredditDetailActivi
 import ml.docilealligator.infinityforreddit.activities.ViewUserDetailActivity;
 import ml.docilealligator.infinityforreddit.activities.ViewVideoActivity;
 import ml.docilealligator.infinityforreddit.apis.GfycatAPI;
+import ml.docilealligator.infinityforreddit.apis.RedgifsAPI;
 import ml.docilealligator.infinityforreddit.apis.StreamableAPI;
 import ml.docilealligator.infinityforreddit.asynctasks.LoadSubredditIcon;
 import ml.docilealligator.infinityforreddit.asynctasks.LoadUserData;
@@ -118,6 +111,14 @@ import ml.docilealligator.infinityforreddit.post.PostPagingSource;
 import ml.docilealligator.infinityforreddit.utils.APIUtils;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
 import ml.docilealligator.infinityforreddit.utils.Utils;
+import ml.docilealligator.infinityforreddit.videoautoplay.CacheManager;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoCreator;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoPlayerViewHelper;
+import ml.docilealligator.infinityforreddit.videoautoplay.Playable;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
 import pl.droidsonroids.gif.GifImageView;
 import retrofit2.Call;
 import retrofit2.Retrofit;
@@ -140,6 +141,7 @@ public class PostDetailRecyclerViewAdapter extends RecyclerView.Adapter<Recycler
     private Retrofit mRedgifsRetrofit;
     private Retrofit mStreamableRetrofit;
     private RedditDataRoomDatabase mRedditDataRoomDatabase;
+    private SharedPreferences mCurrentAccountSharedPreferences;
     private RequestManager mGlide;
     private SaveMemoryCenterInisdeDownsampleStrategy mSaveMemoryCenterInsideDownSampleStrategy;
     private Markwon mPostDetailMarkwon;
@@ -221,6 +223,7 @@ public class PostDetailRecyclerViewAdapter extends RecyclerView.Adapter<Recycler
                                          boolean separatePostAndComments, String accessToken,
                                          String accountName, Post post, Locale locale,
                                          SharedPreferences sharedPreferences,
+                                         SharedPreferences currentAccountSharedPreferences,
                                          SharedPreferences nsfwAndSpoilerSharedPreferences,
                                          SharedPreferences postDetailsSharedPreferences,
                                          ExoCreator exoCreator,
@@ -236,6 +239,7 @@ public class PostDetailRecyclerViewAdapter extends RecyclerView.Adapter<Recycler
         mRedditDataRoomDatabase = redditDataRoomDatabase;
         mGlide = glide;
         mSaveMemoryCenterInsideDownSampleStrategy = new SaveMemoryCenterInisdeDownsampleStrategy(Integer.parseInt(sharedPreferences.getString(SharedPreferencesUtils.POST_FEED_MAX_RESOLUTION, "5000000")));
+        mCurrentAccountSharedPreferences = currentAccountSharedPreferences;
         mSecondaryTextColor = customThemeWrapper.getSecondaryTextColor();
         int markdownColor = customThemeWrapper.getPostContentColor();
         int postSpoilerBackgroundColor = markdownColor | 0xFF000000;
@@ -678,9 +682,10 @@ public class PostDetailRecyclerViewAdapter extends RecyclerView.Adapter<Recycler
 
                 if (mPost.isGfycat() || mPost.isRedgifs() && !mPost.isLoadGfycatOrStreamableVideoSuccess()) {
                     ((PostDetailVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall =
-                            (mPost.isGfycat() ? mGfycatRetrofit : mRedgifsRetrofit).create(GfycatAPI.class).getGfycatData(mPost.getGfycatId());
+                            mPost.isGfycat() ? mGfycatRetrofit.create(GfycatAPI.class).getGfycatData(mPost.getGfycatId()) :
+                                    mRedgifsRetrofit.create(RedgifsAPI.class).getRedgifsData(APIUtils.getRedgifsOAuthHeader(mCurrentAccountSharedPreferences.getString(SharedPreferencesUtils.REDGIFS_ACCESS_TOKEN, "")), mPost.getGfycatId(), APIUtils.getRedgifsUserAgent(mActivity));
                     FetchGfycatOrRedgifsVideoLinks.fetchGfycatOrRedgifsVideoLinksInRecyclerViewAdapter(mExecutor, new Handler(),
-                            ((PostDetailVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall, mPost.getGfycatId(),
+                            ((PostDetailVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall,
                             mPost.isGfycat(), mAutomaticallyTryRedgifs,
                             new FetchGfycatOrRedgifsVideoLinks.FetchGfycatOrRedgifsVideoLinksListener() {
                                 @Override
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/PostRecyclerViewAdapter.java b/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/PostRecyclerViewAdapter.java
index a50fd29b..4bf33ddf 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/PostRecyclerViewAdapter.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/adapters/PostRecyclerViewAdapter.java
@@ -56,14 +56,6 @@ import java.util.concurrent.Executor;
 
 import butterknife.BindView;
 import butterknife.ButterKnife;
-import im.ene.toro.CacheManager;
-import im.ene.toro.ToroPlayer;
-import im.ene.toro.ToroUtil;
-import im.ene.toro.exoplayer.ExoCreator;
-import im.ene.toro.exoplayer.ExoPlayerViewHelper;
-import im.ene.toro.exoplayer.Playable;
-import im.ene.toro.media.PlaybackInfo;
-import im.ene.toro.widget.Container;
 import jp.wasabeef.glide.transformations.BlurTransformation;
 import jp.wasabeef.glide.transformations.RoundedCornersTransformation;
 import ml.docilealligator.infinityforreddit.FetchGfycatOrRedgifsVideoLinks;
@@ -84,6 +76,7 @@ import ml.docilealligator.infinityforreddit.activities.ViewSubredditDetailActivi
 import ml.docilealligator.infinityforreddit.activities.ViewUserDetailActivity;
 import ml.docilealligator.infinityforreddit.activities.ViewVideoActivity;
 import ml.docilealligator.infinityforreddit.apis.GfycatAPI;
+import ml.docilealligator.infinityforreddit.apis.RedgifsAPI;
 import ml.docilealligator.infinityforreddit.apis.StreamableAPI;
 import ml.docilealligator.infinityforreddit.bottomsheetfragments.ShareLinkBottomSheetFragment;
 import ml.docilealligator.infinityforreddit.customtheme.CustomThemeWrapper;
@@ -95,6 +88,14 @@ import ml.docilealligator.infinityforreddit.post.PostPagingSource;
 import ml.docilealligator.infinityforreddit.utils.APIUtils;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
 import ml.docilealligator.infinityforreddit.utils.Utils;
+import ml.docilealligator.infinityforreddit.videoautoplay.CacheManager;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoCreator;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoPlayerViewHelper;
+import ml.docilealligator.infinityforreddit.videoautoplay.Playable;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
 import pl.droidsonroids.gif.GifImageView;
 import retrofit2.Call;
 import retrofit2.Retrofit;
@@ -128,6 +129,7 @@ public class PostRecyclerViewAdapter extends PagingDataAdapter<Post, RecyclerVie
     private BaseActivity mActivity;
     private PostFragment mFragment;
     private SharedPreferences mSharedPreferences;
+    private SharedPreferences mCurrentAccountSharedPreferences;
     private Executor mExecutor;
     private Retrofit mOauthRetrofit;
     private Retrofit mGfycatRetrofit;
@@ -220,7 +222,8 @@ public class PostRecyclerViewAdapter extends PagingDataAdapter<Post, RecyclerVie
                                    Retrofit gfycatRetrofit, Retrofit redgifsRetrofit, Retrofit streambleRetrofit,
                                    CustomThemeWrapper customThemeWrapper, Locale locale,
                                    String accessToken, String accountName, int postType, int postLayout, boolean displaySubredditName,
-                                   SharedPreferences sharedPreferences, SharedPreferences nsfwAndSpoilerSharedPreferences,
+                                   SharedPreferences sharedPreferences, SharedPreferences currentAccountSharedPreferences,
+                                   SharedPreferences nsfwAndSpoilerSharedPreferences,
                                    SharedPreferences postHistorySharedPreferences,
                                    ExoCreator exoCreator, Callback callback) {
         super(DIFF_CALLBACK);
@@ -228,6 +231,7 @@ public class PostRecyclerViewAdapter extends PagingDataAdapter<Post, RecyclerVie
             mActivity = activity;
             mFragment = fragment;
             mSharedPreferences = sharedPreferences;
+            mCurrentAccountSharedPreferences = currentAccountSharedPreferences;
             mExecutor = executor;
             mOauthRetrofit = oauthRetrofit;
             mGfycatRetrofit = gfycatRetrofit;
@@ -705,9 +709,10 @@ public class PostRecyclerViewAdapter extends PagingDataAdapter<Post, RecyclerVie
 
                     if ((post.isGfycat() || post.isRedgifs()) && !post.isLoadGfycatOrStreamableVideoSuccess()) {
                         ((PostVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall =
-                                (post.isGfycat() ? mGfycatRetrofit : mRedgifsRetrofit).create(GfycatAPI.class).getGfycatData(post.getGfycatId());
+                                post.isGfycat() ? mGfycatRetrofit.create(GfycatAPI.class).getGfycatData(post.getGfycatId()) :
+                                        mRedgifsRetrofit.create(RedgifsAPI.class).getRedgifsData(APIUtils.getRedgifsOAuthHeader(mCurrentAccountSharedPreferences.getString(SharedPreferencesUtils.REDGIFS_ACCESS_TOKEN, "")), post.getGfycatId(), APIUtils.getRedgifsUserAgent(mActivity));
                         FetchGfycatOrRedgifsVideoLinks.fetchGfycatOrRedgifsVideoLinksInRecyclerViewAdapter(mExecutor, new Handler(),
-                                ((PostVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall, post.getGfycatId(),
+                                ((PostVideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall,
                                 post.isGfycat(), mAutomaticallyTryRedgifs,
                                 new FetchGfycatOrRedgifsVideoLinks.FetchGfycatOrRedgifsVideoLinksListener() {
                                     @Override
@@ -870,9 +875,10 @@ public class PostRecyclerViewAdapter extends PagingDataAdapter<Post, RecyclerVie
 
                     if ((post.isGfycat() || post.isRedgifs()) && !post.isLoadGfycatOrStreamableVideoSuccess()) {
                         ((PostCard2VideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall =
-                                (post.isGfycat() ? mGfycatRetrofit : mRedgifsRetrofit).create(GfycatAPI.class).getGfycatData(post.getGfycatId());
+                                post.isGfycat() ? mGfycatRetrofit.create(GfycatAPI.class).getGfycatData(post.getGfycatId()) :
+                                        mRedgifsRetrofit.create(RedgifsAPI.class).getRedgifsData(APIUtils.getRedgifsOAuthHeader(mCurrentAccountSharedPreferences.getString(SharedPreferencesUtils.REDGIFS_ACCESS_TOKEN, "")), post.getGfycatId(), APIUtils.getRedgifsUserAgent(mActivity));
                         FetchGfycatOrRedgifsVideoLinks.fetchGfycatOrRedgifsVideoLinksInRecyclerViewAdapter(mExecutor, new Handler(),
-                                ((PostCard2VideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall, post.getGfycatId(),
+                                ((PostCard2VideoAutoplayViewHolder) holder).fetchGfycatOrStreamableVideoCall,
                                 post.isGfycat(), mAutomaticallyTryRedgifs,
                                 new FetchGfycatOrRedgifsVideoLinks.FetchGfycatOrRedgifsVideoLinksListener() {
                                     @Override
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/apis/RedgifsAPI.java b/app/src/main/java/ml/docilealligator/infinityforreddit/apis/RedgifsAPI.java
new file mode 100644
index 00000000..1a4bf809
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/apis/RedgifsAPI.java
@@ -0,0 +1,21 @@
+package ml.docilealligator.infinityforreddit.apis;
+
+import java.util.Map;
+
+import retrofit2.Call;
+import retrofit2.http.FieldMap;
+import retrofit2.http.FormUrlEncoded;
+import retrofit2.http.GET;
+import retrofit2.http.HeaderMap;
+import retrofit2.http.POST;
+import retrofit2.http.Path;
+import retrofit2.http.Query;
+
+public interface RedgifsAPI {
+    @GET("/v2/gifs/{id}")
+    Call<String> getRedgifsData(@HeaderMap Map<String, String> headers, @Path("id") String id, @Query("user-agent") String userAgent);
+
+    @FormUrlEncoded
+    @POST("/v2/oauth/client")
+    Call<String> getRedgifsAccessToken(@FieldMap Map<String, String> params);
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/customviews/CustomToroContainer.java b/app/src/main/java/ml/docilealligator/infinityforreddit/customviews/CustomToroContainer.java
index 8d925ae6..74d367b8 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/customviews/CustomToroContainer.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/customviews/CustomToroContainer.java
@@ -5,7 +5,7 @@ import android.util.AttributeSet;
 
 import androidx.annotation.Nullable;
 
-import im.ene.toro.widget.Container;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
 
 public class CustomToroContainer extends Container {
     private OnWindowFocusChangedListener listener;
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/customviews/LoopAvailableExoCreator.java b/app/src/main/java/ml/docilealligator/infinityforreddit/customviews/LoopAvailableExoCreator.java
index 5ccda4be..01fc9a32 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/customviews/LoopAvailableExoCreator.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/customviews/LoopAvailableExoCreator.java
@@ -7,10 +7,10 @@ import androidx.annotation.NonNull;
 import com.google.android.exoplayer2.Player;
 import com.google.android.exoplayer2.SimpleExoPlayer;
 
-import im.ene.toro.exoplayer.Config;
-import im.ene.toro.exoplayer.DefaultExoCreator;
-import im.ene.toro.exoplayer.ToroExo;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
+import ml.docilealligator.infinityforreddit.videoautoplay.Config;
+import ml.docilealligator.infinityforreddit.videoautoplay.DefaultExoCreator;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroExo;
 
 public class LoopAvailableExoCreator extends DefaultExoCreator {
     private final SharedPreferences sharedPreferences;
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/HistoryPostFragment.java b/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/HistoryPostFragment.java
index 76f3330c..06ef97e9 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/HistoryPostFragment.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/HistoryPostFragment.java
@@ -1,7 +1,7 @@
 package ml.docilealligator.infinityforreddit.fragments;
 
-import static im.ene.toro.media.PlaybackInfo.INDEX_UNSET;
-import static im.ene.toro.media.PlaybackInfo.TIME_UNSET;
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.INDEX_UNSET;
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.TIME_UNSET;
 
 import android.content.Context;
 import android.content.SharedPreferences;
@@ -63,9 +63,6 @@ import javax.inject.Named;
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import butterknife.Unbinder;
-import im.ene.toro.exoplayer.ExoCreator;
-import im.ene.toro.media.PlaybackInfo;
-import im.ene.toro.media.VolumeInfo;
 import ml.docilealligator.infinityforreddit.FetchPostFilterReadPostsAndConcatenatedSubredditNames;
 import ml.docilealligator.infinityforreddit.FragmentCommunicator;
 import ml.docilealligator.infinityforreddit.Infinity;
@@ -129,6 +126,9 @@ import ml.docilealligator.infinityforreddit.postfilter.PostFilter;
 import ml.docilealligator.infinityforreddit.postfilter.PostFilterUsage;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
 import ml.docilealligator.infinityforreddit.utils.Utils;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoCreator;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
 import retrofit2.Retrofit;
 
 public class HistoryPostFragment extends Fragment implements FragmentCommunicator {
@@ -177,6 +177,9 @@ public class HistoryPostFragment extends Fragment implements FragmentCommunicato
     @Named("default")
     SharedPreferences mSharedPreferences;
     @Inject
+    @Named("current_account")
+    SharedPreferences mCurrentAccountSharedPreferences;
+    @Inject
     @Named("post_layout")
     SharedPreferences mPostLayoutSharedPreferences;
     @Inject
@@ -378,7 +381,7 @@ public class HistoryPostFragment extends Fragment implements FragmentCommunicato
             mAdapter = new HistoryPostRecyclerViewAdapter(activity, this, mExecutor, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mCustomThemeWrapper, locale,
                     accessToken, accountName, postType, postLayout, true,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences,
                     mExoCreator, new HistoryPostRecyclerViewAdapter.Callback() {
                 @Override
                 public void typeChipClicked(int filter) {
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/PostFragment.java b/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/PostFragment.java
index 5551d31e..2cd04385 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/PostFragment.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/PostFragment.java
@@ -1,8 +1,7 @@
 package ml.docilealligator.infinityforreddit.fragments;
 
-
-import static im.ene.toro.media.PlaybackInfo.INDEX_UNSET;
-import static im.ene.toro.media.PlaybackInfo.TIME_UNSET;
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.INDEX_UNSET;
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.TIME_UNSET;
 
 import android.content.Context;
 import android.content.Intent;
@@ -67,9 +66,6 @@ import javax.inject.Named;
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import butterknife.Unbinder;
-import im.ene.toro.exoplayer.ExoCreator;
-import im.ene.toro.media.PlaybackInfo;
-import im.ene.toro.media.VolumeInfo;
 import ml.docilealligator.infinityforreddit.ActivityToolbarInterface;
 import ml.docilealligator.infinityforreddit.FetchPostFilterReadPostsAndConcatenatedSubredditNames;
 import ml.docilealligator.infinityforreddit.FragmentCommunicator;
@@ -137,6 +133,9 @@ import ml.docilealligator.infinityforreddit.postfilter.PostFilter;
 import ml.docilealligator.infinityforreddit.postfilter.PostFilterUsage;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
 import ml.docilealligator.infinityforreddit.utils.Utils;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoCreator;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
 import retrofit2.Retrofit;
 
 
@@ -195,6 +194,9 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
     @Named("default")
     SharedPreferences mSharedPreferences;
     @Inject
+    @Named("current_account")
+    SharedPreferences mCurrentAccountSharedPreferences;
+    @Inject
     @Named("sort_type")
     SharedPreferences mSortTypeSharedPreferences;
     @Inject
@@ -458,7 +460,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             mAdapter = new PostRecyclerViewAdapter(activity, this, mExecutor, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mCustomThemeWrapper, locale,
                     accessToken, accountName, postType, postLayout, true,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
                     mExoCreator, new PostRecyclerViewAdapter.Callback() {
                 @Override
                 public void typeChipClicked(int filter) {
@@ -535,7 +537,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             mAdapter = new PostRecyclerViewAdapter(activity, this, mExecutor, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mCustomThemeWrapper, locale,
                     accessToken, accountName, postType, postLayout, displaySubredditName,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
                     mExoCreator, new PostRecyclerViewAdapter.Callback() {
                 @Override
                 public void typeChipClicked(int filter) {
@@ -606,7 +608,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             mAdapter = new PostRecyclerViewAdapter(activity, this, mExecutor, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mCustomThemeWrapper, locale,
                     accessToken, accountName, postType, postLayout, true,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
                     mExoCreator, new PostRecyclerViewAdapter.Callback() {
                 @Override
                 public void typeChipClicked(int filter) {
@@ -671,7 +673,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             mAdapter = new PostRecyclerViewAdapter(activity, this, mExecutor, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mCustomThemeWrapper, locale,
                     accessToken, accountName, postType, postLayout, true,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
                     mExoCreator, new PostRecyclerViewAdapter.Callback() {
                 @Override
                 public void typeChipClicked(int filter) {
@@ -732,7 +734,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             mAdapter = new PostRecyclerViewAdapter(activity, this, mExecutor, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mCustomThemeWrapper, locale,
                     accessToken, accountName, postType, postLayout, true,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
                     mExoCreator, new PostRecyclerViewAdapter.Callback() {
                 @Override
                 public void typeChipClicked(int filter) {
@@ -792,7 +794,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             mAdapter = new PostRecyclerViewAdapter(activity, this, mExecutor, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mCustomThemeWrapper, locale,
                     accessToken, accountName, postType, postLayout, true,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
                     mExoCreator, new PostRecyclerViewAdapter.Callback() {
                 @Override
                 public void typeChipClicked(int filter) {
@@ -849,7 +851,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             mAdapter = new PostRecyclerViewAdapter(activity, this, mExecutor, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mCustomThemeWrapper, locale,
                     accessToken, accountName, postType, postLayout, true,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostHistorySharedPreferences,
                     mExoCreator, new PostRecyclerViewAdapter.Callback() {
                 @Override
                 public void typeChipClicked(int filter) {
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/ViewPostDetailFragment.java b/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/ViewPostDetailFragment.java
index 5821b2fd..d1cc9976 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/ViewPostDetailFragment.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/fragments/ViewPostDetailFragment.java
@@ -1,9 +1,9 @@
 package ml.docilealligator.infinityforreddit.fragments;
 
-import static im.ene.toro.media.PlaybackInfo.INDEX_UNSET;
-import static im.ene.toro.media.PlaybackInfo.TIME_UNSET;
 import static ml.docilealligator.infinityforreddit.activities.CommentActivity.RETURN_EXTRA_COMMENT_DATA_KEY;
 import static ml.docilealligator.infinityforreddit.activities.CommentActivity.WRITE_COMMENT_REQUEST_CODE;
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.INDEX_UNSET;
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.TIME_UNSET;
 
 import android.annotation.SuppressLint;
 import android.app.Activity;
@@ -63,9 +63,6 @@ import javax.inject.Named;
 
 import butterknife.BindView;
 import butterknife.ButterKnife;
-import im.ene.toro.exoplayer.ExoCreator;
-import im.ene.toro.media.PlaybackInfo;
-import im.ene.toro.media.VolumeInfo;
 import ml.docilealligator.infinityforreddit.DeleteThing;
 import ml.docilealligator.infinityforreddit.Flair;
 import ml.docilealligator.infinityforreddit.FragmentCommunicator;
@@ -113,6 +110,9 @@ import ml.docilealligator.infinityforreddit.subreddit.SubredditData;
 import ml.docilealligator.infinityforreddit.utils.APIUtils;
 import ml.docilealligator.infinityforreddit.utils.SharedPreferencesUtils;
 import ml.docilealligator.infinityforreddit.utils.Utils;
+import ml.docilealligator.infinityforreddit.videoautoplay.ExoCreator;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
@@ -556,7 +556,7 @@ public class ViewPostDetailFragment extends Fragment implements FragmentCommunic
                     this, mExecutor, mCustomThemeWrapper, mRetrofit, mOauthRetrofit, mGfycatRetrofit,
                     mRedgifsRetrofit, mStreamableRetrofit, mRedditDataRoomDatabase, mGlide,
                     mSeparatePostAndComments, mAccessToken, mAccountName, mPost, mLocale,
-                    mSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostDetailsSharedPreferences,
+                    mSharedPreferences, mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences, mPostDetailsSharedPreferences,
                     mExoCreator, post -> EventBus.getDefault().post(new PostUpdateEventToPostList(mPost, postListPosition)));
             mCommentsAdapter = new CommentsRecyclerViewAdapter(activity,
                     this, mCustomThemeWrapper, mExecutor, mRetrofit, mOauthRetrofit,
@@ -1239,8 +1239,8 @@ public class ViewPostDetailFragment extends Fragment implements FragmentCommunic
                                     mRetrofit, mOauthRetrofit, mGfycatRetrofit, mRedgifsRetrofit,
                                     mStreamableRetrofit, mRedditDataRoomDatabase, mGlide, mSeparatePostAndComments,
                                     mAccessToken, mAccountName, mPost, mLocale, mSharedPreferences,
-                                    mNsfwAndSpoilerSharedPreferences, mPostDetailsSharedPreferences,
-                                    mExoCreator,
+                                    mCurrentAccountSharedPreferences, mNsfwAndSpoilerSharedPreferences,
+                                    mPostDetailsSharedPreferences, mExoCreator,
                                     post1 -> EventBus.getDefault().post(new PostUpdateEventToPostList(mPost, postListPosition)));
 
                             mCommentsAdapter = new CommentsRecyclerViewAdapter(activity,
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/utils/APIUtils.java b/app/src/main/java/ml/docilealligator/infinityforreddit/utils/APIUtils.java
index 927f564a..248c917b 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/utils/APIUtils.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/utils/APIUtils.java
@@ -1,5 +1,6 @@
 package ml.docilealligator.infinityforreddit.utils;
 
+import android.content.Context;
 import android.util.Base64;
 
 import java.util.HashMap;
@@ -19,7 +20,7 @@ public class APIUtils {
     public static final String API_UPLOAD_MEDIA_URI = "https://reddit-uploaded-media.s3-accelerate.amazonaws.com";
     public static final String API_UPLOAD_VIDEO_URI = "https://reddit-uploaded-video.s3-accelerate.amazonaws.com";
     public static final String GFYCAT_API_BASE_URI = "https://api.gfycat.com/v1/gfycats/";
-    public static final String REDGIFS_API_BASE_URI = "https://api.redgifs.com/v2/gifs/";
+    public static final String REDGIFS_API_BASE_URI = "https://api.redgifs.com";
     public static final String IMGUR_API_BASE_URI = "https://api.imgur.com/3/";
     public static final String PUSHSHIFT_API_BASE_URI = "https://api.pushshift.io/";
     public static final String REVEDDIT_API_BASE_URI = "https://api.reveddit.com/";
@@ -27,8 +28,11 @@ public class APIUtils {
     public static final String STREAMABLE_API_BASE_URI = "https://api.streamable.com";
 
     public static final String CLIENT_ID_KEY = "client_id";
+    public static final String CLIENT_SECRET_KEY = "client_secret";
     public static final String CLIENT_ID = "NOe2iKrPPzwscA";
     public static final String IMGUR_CLIENT_ID = "Client-ID cc671794e0ab397";
+    public static final String REDGIFS_CLIENT_ID = "1828d0bcc93-15ac-bde6-0005-d2ecbe8daab3";
+    public static final String REDGIFS_CLIENT_SECRET = "TJBlw7jRXW65NAGgFBtgZHu97WlzRXHYybK81sZ9dLM=";
     public static final String RESPONSE_TYPE_KEY = "response_type";
     public static final String RESPONSE_TYPE = "code";
     public static final String STATE_KEY = "state";
@@ -48,6 +52,7 @@ public class APIUtils {
 
     public static final String GRANT_TYPE_KEY = "grant_type";
     public static final String GRANT_TYPE_REFRESH_TOKEN = "refresh_token";
+    public static final String GRANT_TYPE_CLIENT_CREDENTIALS = "client_credentials";
     public static final String REFRESH_TOKEN_KEY = "refresh_token";
 
     public static final String DIR_KEY = "dir";
@@ -111,6 +116,11 @@ public class APIUtils {
     public static final String REFERER_KEY = "Referer";
     public static final String REVEDDIT_REFERER = "https://www.reveddit.com/";
 
+    /*public static final String HOST_KEY = "Host";
+    public static final String REDGIFS_HOST = "api.redgifs.com";
+    public static final String CONTENT_TYPE_KEY = "Content-Type";
+    public static final String */
+
     public static Map<String, String> getHttpBasicAuthHeader() {
         Map<String, String> params = new HashMap<>();
         String credentials = String.format("%s:%s", APIUtils.CLIENT_ID, "");
@@ -126,6 +136,12 @@ public class APIUtils {
         return params;
     }
 
+    public static Map<String, String> getRedgifsOAuthHeader(String redgifsAccessToken) {
+        Map<String, String> params = new HashMap<>();
+        params.put(APIUtils.AUTHORIZATION_KEY, APIUtils.AUTHORIZATION_BASE + redgifsAccessToken);
+        return params;
+    }
+
     public static RequestBody getRequestBody(String s) {
         return RequestBody.create(s, MediaType.parse("text/plain"));
     }
@@ -137,4 +153,23 @@ public class APIUtils {
         params.put(APIUtils.USER_AGENT_KEY, APIUtils.USER_AGENT);
         return params;
     }
+
+    public static String getRedgifsUserAgent(Context context) {
+        return APIUtils.USER_AGENT;
+        /*String versionName;
+        try {
+            String packageName = context.getPackageName();
+            PackageInfo info = context.getPackageManager().getPackageInfo(packageName, 0);
+            versionName = info.versionName;
+        } catch (Exception e) {
+            versionName = "?";
+        }
+        return "Toro ExoPlayer Extension, v3.7.0.2010003"
+                + "/"
+                + versionName
+                + " (Linux;Android "
+                + Build.VERSION.RELEASE
+                + ") "
+                + ExoPlayerLibraryInfo.VERSION_SLASHY;*/
+    }
 }
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/utils/SharedPreferencesUtils.java b/app/src/main/java/ml/docilealligator/infinityforreddit/utils/SharedPreferencesUtils.java
index 3b431a42..29f42e4b 100644
--- a/app/src/main/java/ml/docilealligator/infinityforreddit/utils/SharedPreferencesUtils.java
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/utils/SharedPreferencesUtils.java
@@ -337,6 +337,7 @@ public class SharedPreferencesUtils {
     public static final String ACCOUNT_NAME = "account_name";
     public static final String ACCESS_TOKEN = "access_token";
     public static final String ACCOUNT_IMAGE_URL = "account_image_url";
+    public static final String REDGIFS_ACCESS_TOKEN = "redgifs_access_token";
 
     public static final String NAVIGATION_DRAWER_SHARED_PREFERENCES_FILE = "ml.docilealligator.infinityforreddit.navigation_drawer";
     public static final String COLLAPSE_ACCOUNT_SECTION = "collapse_account_section";
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/AdsExoPlayerViewHelper.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/AdsExoPlayerViewHelper.java
new file mode 100644
index 00000000..22a63afc
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/AdsExoPlayerViewHelper.java
@@ -0,0 +1,188 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import android.content.Context;
+import android.net.Uri;
+import android.view.View;
+import android.view.ViewGroup;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.source.ads.AdsLoader;
+import com.google.android.exoplayer2.ui.PlayerView;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.Beta;
+
+/**
+ * A {@link ToroPlayerHelper} to integrate ExoPlayer IMA Extension. Work together with {@link
+ * AdsPlayable}.
+ *
+ * @author eneim (2018/08/22).
+ * @since 3.6.0.2802
+ */
+@SuppressWarnings("unused") @Beta //
+public class AdsExoPlayerViewHelper extends ExoPlayerViewHelper {
+
+  static class DefaultAdViewProvider implements AdsLoader.AdViewProvider {
+
+    @NonNull final ViewGroup viewGroup;
+
+    DefaultAdViewProvider(@NonNull ViewGroup viewGroup) {
+      this.viewGroup = viewGroup;
+    }
+
+    @Override public ViewGroup getAdViewGroup() {
+      return this.viewGroup;
+    }
+
+    @Override public View[] getAdOverlayViews() {
+      return new View[0];
+    }
+  }
+
+  private static AdsPlayable createPlayable(  ///
+                                                                    ToroPlayer player,      //
+                                                                    ExoCreator creator,     //
+                                                                    Uri contentUri,         //
+                                                                    String fileExt,         //
+                                                                    AdsLoader adsLoader,    //
+                                                                    AdsLoader.AdViewProvider adViewProvider   //
+  ) {
+    return new AdsPlayable(creator, contentUri, fileExt, player, adsLoader, adViewProvider);
+  }
+
+  private static AdsPlayable createPlayable(  //
+                                                                    ToroPlayer player,      //
+                                                                    Config config,          //
+                                                                    Uri contentUri,         //
+                                                                    String fileExt,         //
+                                                                    AdsLoader adsLoader,    //
+                                                                    AdsLoader.AdViewProvider adViewProvider   //
+  ) {
+    Context context = player.getPlayerView().getContext();
+    return createPlayable(player, ToroExo.with(context).getCreator(config), contentUri, fileExt,
+        adsLoader, adViewProvider);
+  }
+
+  private static AdsPlayable createPlayable(  //
+                                                                    ToroPlayer player,      //
+                                                                    Uri contentUri,         //
+                                                                    String fileExt,         //
+                                                                    AdsLoader adsLoader,    //
+                                                                    AdsLoader.AdViewProvider adViewProvider   //
+  ) {
+    Context context = player.getPlayerView().getContext();
+    return createPlayable(player, ToroExo.with(context).getDefaultCreator(), contentUri, fileExt,
+        adsLoader, adViewProvider);
+  }
+
+  // Neither ExoCreator nor Config are provided.
+
+  /**
+   * Create new {@link AdsExoPlayerViewHelper} for a {@link ToroPlayer} and {@link AdsLoader}.
+   *
+   * @param adContainer if {@code null} then overlay of {@link PlayerView} will be used.
+   */
+  @Deprecated
+  public AdsExoPlayerViewHelper(        //
+      @NonNull ToroPlayer player,       //
+      @NonNull Uri uri,                 //
+      @Nullable String fileExt,         //
+      @NonNull AdsLoader adsLoader,     //
+      @Nullable ViewGroup adContainer   //
+  ) {
+    super(player,
+        createPlayable(player, uri, fileExt, adsLoader,
+            adContainer != null ? new DefaultAdViewProvider(adContainer) : null));
+  }
+
+  public AdsExoPlayerViewHelper(        //
+      @NonNull ToroPlayer player,       //
+      @NonNull Uri uri,                 //
+      @Nullable String fileExt,         //
+      @NonNull AdsLoader adsLoader,     //
+      @Nullable ViewGroup adContainer,   // will be ignored
+      @Nullable AdsLoader.AdViewProvider adViewProvider   //
+  ) {
+    super(player, createPlayable(player, uri, fileExt, adsLoader, adViewProvider));
+  }
+
+  // ExoCreator is provided.
+
+  /**
+   * Create new {@link AdsExoPlayerViewHelper} for a {@link ToroPlayer} and {@link AdsLoader}.
+   *
+   * @param adContainer if {@code null} then overlay of {@link PlayerView} will be used.
+   */
+  @Deprecated
+  public AdsExoPlayerViewHelper(        //
+                                        @NonNull ToroPlayer player,       //
+                                        @NonNull Uri uri,                 //
+                                        @Nullable String fileExt,         //
+                                        @NonNull AdsLoader adsLoader,     //
+                                        @Nullable ViewGroup adContainer,  //
+                                        @NonNull ExoCreator creator       //
+  ) {
+    super(player, createPlayable(player, creator, uri, fileExt, adsLoader,
+        adContainer != null ? new DefaultAdViewProvider(adContainer) : null));
+  }
+
+  public AdsExoPlayerViewHelper(        //
+                                        @NonNull ToroPlayer player,       //
+                                        @NonNull Uri uri,                 //
+                                        @Nullable String fileExt,         //
+                                        @NonNull AdsLoader adsLoader,     //
+                                        @Nullable ViewGroup adContainer,  // will be ignored
+                                        @Nullable AdsLoader.AdViewProvider adViewProvider,  //
+                                        @NonNull ExoCreator creator       //
+  ) {
+    super(player, createPlayable(player, creator, uri, fileExt, adsLoader, adViewProvider));
+  }
+  // Config is provided.
+
+  /**
+   * Create new {@link AdsExoPlayerViewHelper} for a {@link ToroPlayer} and {@link AdsLoader}.
+   *
+   * @param adContainer if {@code null} then overlay of {@link PlayerView} will be used.
+   */
+  @Deprecated
+  public AdsExoPlayerViewHelper(        //
+      @NonNull ToroPlayer player,       //
+      @NonNull Uri uri,                 //
+      @Nullable String fileExt,         //
+      @NonNull AdsLoader adsLoader,     //
+      @Nullable ViewGroup adContainer,  //
+      @NonNull Config config            //
+  ) {
+    super(player, createPlayable(player, config, uri, fileExt, adsLoader,
+        adContainer != null ? new DefaultAdViewProvider(adContainer) : null));
+  }
+
+  public AdsExoPlayerViewHelper(        //
+      @NonNull ToroPlayer player,       //
+      @NonNull Uri uri,                 //
+      @Nullable String fileExt,         //
+      @NonNull AdsLoader adsLoader,     //
+      @Nullable ViewGroup adContainer,  // will be ignored
+      @Nullable AdsLoader.AdViewProvider adViewProvider,  //
+      @NonNull Config config            //
+  ) {
+    super(player, createPlayable(player, config, uri, fileExt, adsLoader, adViewProvider));
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/AdsPlayable.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/AdsPlayable.java
new file mode 100644
index 00000000..666b3815
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/AdsPlayable.java
@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import android.net.Uri;
+import android.view.View;
+import android.view.ViewGroup;
+
+import androidx.annotation.CallSuper;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.source.ads.AdsLoader;
+import com.google.android.exoplayer2.source.ads.AdsMediaSource;
+import com.google.android.exoplayer2.ui.PlayerView;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.Beta;
+
+/**
+ * A {@link Playable} that is able to integrate with {@link AdsLoader}.
+ *
+ * @author eneim (2018/08/22).
+ * @since 3.6.0.2802
+ */
+@Beta //
+public class AdsPlayable extends ExoPlayable {
+
+  static class FactoryImpl implements AdsMediaSource.MediaSourceFactory {
+
+    @NonNull final ExoCreator creator;
+    @NonNull final ToroPlayer player;
+
+    FactoryImpl(@NonNull ExoCreator creator, @NonNull ToroPlayer player) {
+      this.creator = creator;
+      this.player = player;
+    }
+
+    @Override public MediaSource createMediaSource(Uri uri) {
+      return this.creator.createMediaSource(uri, null);
+    }
+
+    @Override public int[] getSupportedTypes() {
+      // IMA does not support Smooth Streaming ads.
+      return new int[] { C.TYPE_DASH, C.TYPE_HLS, C.TYPE_OTHER };
+    }
+  }
+
+  @NonNull private final AdsLoader adsLoader;
+  @NonNull private final FactoryImpl factory;
+  @Nullable private final AdsLoader.AdViewProvider adViewProvider;
+
+  /**
+   * @deprecated Use the constructors that use {@link AdsLoader.AdViewProvider} instead.
+   */
+  @Deprecated
+  public AdsPlayable(ExoCreator creator, Uri uri, String fileExt, ToroPlayer player,
+                     @NonNull AdsLoader adsLoader, @Nullable final ViewGroup adsContainer) {
+    super(creator, uri, fileExt);
+    this.adsLoader = adsLoader;
+    this.adViewProvider = adsContainer == null ? null
+        : new AdsExoPlayerViewHelper.DefaultAdViewProvider(adsContainer);
+    this.factory = new FactoryImpl(this.creator, player);
+  }
+
+  @SuppressWarnings("WeakerAccess")
+  public AdsPlayable(ExoCreator creator, Uri uri, String fileExt, ToroPlayer player,
+                     @NonNull AdsLoader adsLoader, @Nullable AdsLoader.AdViewProvider adViewProvider) {
+    super(creator, uri, fileExt);
+    this.adsLoader = adsLoader;
+    this.adViewProvider = adViewProvider;
+    this.factory = new FactoryImpl(this.creator, player);
+  }
+
+  @CallSuper
+  @Override public void prepare(boolean prepareSource) {
+    this.mediaSource = createAdsMediaSource(creator, mediaUri, fileExt, //
+        factory.player, adsLoader, adViewProvider, factory);
+    super.prepare(prepareSource);
+  }
+
+  @Override protected void beforePrepareMediaSource() {
+    super.beforePrepareMediaSource();
+    adsLoader.setPlayer(player);
+  }
+
+  @Override public void release() {
+    adsLoader.setPlayer(null);
+    super.release();
+  }
+
+  private static MediaSource createAdsMediaSource(ExoCreator creator, Uri uri, String fileExt,
+                                                  ToroPlayer player, AdsLoader adsLoader, AdsLoader.AdViewProvider adViewProvider,
+                                                  AdsMediaSource.MediaSourceFactory factory) {
+    MediaSource original = creator.createMediaSource(uri, fileExt);
+    View playerView = player.getPlayerView();
+    if (!(playerView instanceof PlayerView)) {
+      throw new IllegalArgumentException("Require PlayerView");
+    }
+
+    return new AdsMediaSource(original, factory, adsLoader,
+        adViewProvider == null ? (PlayerView) playerView : adViewProvider);
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/BaseMeter.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/BaseMeter.java
new file mode 100644
index 00000000..539919b0
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/BaseMeter.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import android.os.Handler;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.upstream.BandwidthMeter;
+import com.google.android.exoplayer2.upstream.DataSource;
+import com.google.android.exoplayer2.upstream.DataSpec;
+import com.google.android.exoplayer2.upstream.DefaultBandwidthMeter;
+import com.google.android.exoplayer2.upstream.TransferListener;
+
+/**
+ * Abstract the {@link DefaultBandwidthMeter}, provide a wider use.
+ *
+ * @author eneim (2018/01/26).
+ * @since 3.4.0
+ */
+
+@SuppressWarnings("WeakerAccess") //
+public final class BaseMeter<T extends BandwidthMeter> implements BandwidthMeter, TransferListener {
+
+  @NonNull protected final T bandwidthMeter;
+  @NonNull protected final TransferListener transferListener;
+
+  /**
+   * @deprecated use {@link #BaseMeter(BandwidthMeter)} instead.
+   */
+  @SuppressWarnings({ "unused" }) //
+  @Deprecated //
+  public BaseMeter(@NonNull T bandwidthMeter, @NonNull TransferListener transferListener) {
+    this(bandwidthMeter);
+  }
+
+  public BaseMeter(@NonNull T bandwidthMeter) {
+    this.bandwidthMeter = ToroUtil.checkNotNull(bandwidthMeter);
+    this.transferListener = ToroUtil.checkNotNull(this.bandwidthMeter.getTransferListener());
+  }
+
+  @Override public long getBitrateEstimate() {
+    return bandwidthMeter.getBitrateEstimate();
+  }
+
+  @Override @Nullable public TransferListener getTransferListener() {
+    return bandwidthMeter.getTransferListener();
+  }
+
+  @Override public void addEventListener(Handler eventHandler, EventListener eventListener) {
+    bandwidthMeter.addEventListener(eventHandler, eventListener);
+  }
+
+  @Override public void removeEventListener(EventListener eventListener) {
+    bandwidthMeter.removeEventListener(eventListener);
+  }
+
+  @Override
+  public void onTransferInitializing(DataSource source, DataSpec dataSpec, boolean isNetwork) {
+    transferListener.onTransferInitializing(source, dataSpec, isNetwork);
+  }
+
+  @Override public void onTransferStart(DataSource source, DataSpec dataSpec, boolean isNetwork) {
+    transferListener.onTransferStart(source, dataSpec, isNetwork);
+  }
+
+  @Override public void onBytesTransferred(DataSource source, DataSpec dataSpec, boolean isNetwork,
+      int bytesTransferred) {
+    transferListener.onBytesTransferred(source, dataSpec, isNetwork, bytesTransferred);
+  }
+
+  @Override public void onTransferEnd(DataSource source, DataSpec dataSpec, boolean isNetwork) {
+    transferListener.onTransferEnd(source, dataSpec, isNetwork);
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/CacheManager.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/CacheManager.java
new file mode 100644
index 00000000..04342641
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/CacheManager.java
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.recyclerview.widget.RecyclerView;
+
+import java.util.LinkedHashMap;
+
+/**
+ * {@link CacheManager} is a helper interface used by {@link Container} to manage the
+ * {@link PlaybackInfo} of {@link ToroPlayer}s. For each {@link ToroPlayer},
+ * {@link CacheManager} will ask for a unique key for its {@link PlaybackInfo} cache.
+ * {@link Container} uses a {@link LinkedHashMap} to implement the caching mechanism, so
+ * {@link CacheManager} must provide keys which are uniquely distinguished by
+ * {@link Object#equals(Object)}.
+ *
+ * @author eneim (7/5/17).
+ */
+public interface CacheManager {
+
+  /**
+   * Get the unique key for the {@link ToroPlayer} of a specific order. Note that this key must
+   * also be managed by {@link RecyclerView.Adapter} so that it prevents the uniqueness at data
+   * change events.
+   *
+   * @param order order of the {@link ToroPlayer}.
+   * @return the unique key of the {@link ToroPlayer}.
+   */
+  @Nullable Object getKeyForOrder(int order);
+
+  /**
+   * Get the order of a specific key value. Returning a {@code null} order value here will tell
+   * {@link Container} to ignore this key's cache order.
+   *
+   * @param key the key value to lookup.
+   * @return the order of the {@link ToroPlayer} whose unique key value is key.
+   */
+  @Nullable Integer getOrderForKey(@NonNull Object key);
+
+  /**
+   * A built-in {@link CacheManager} that use the order as the unique key. Note that this is not
+   * data-changes-proof. Which means that after data change events, the map may need to be
+   * updated.
+   */
+  CacheManager DEFAULT = new CacheManager() {
+    @Override public Object getKeyForOrder(int order) {
+      return order;
+    }
+
+    @Override public Integer getOrderForKey(@NonNull Object key) {
+      return key instanceof Integer ? (Integer) key : null;
+    }
+  };
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/Config.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/Config.java
new file mode 100644
index 00000000..7fe095d4
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/Config.java
@@ -0,0 +1,195 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static com.google.android.exoplayer2.DefaultRenderersFactory.EXTENSION_RENDERER_MODE_OFF;
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.checkNotNull;
+
+import android.content.Context;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.core.util.ObjectsCompat;
+
+import com.google.android.exoplayer2.DefaultLoadControl;
+import com.google.android.exoplayer2.DefaultRenderersFactory.ExtensionRendererMode;
+import com.google.android.exoplayer2.LoadControl;
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.drm.DrmSessionManager;
+import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
+import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.upstream.DataSource;
+import com.google.android.exoplayer2.upstream.DefaultBandwidthMeter;
+import com.google.android.exoplayer2.upstream.cache.Cache;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.Beta;
+
+/**
+ * Necessary configuration for {@link ExoCreator} to produces {@link SimpleExoPlayer} and
+ * {@link MediaSource}. Instance of this class must be construct using {@link Builder}.
+ *
+ * @author eneim (2018/01/23).
+ * @since 3.4.0
+ */
+
+@SuppressWarnings("SimplifiableIfStatement")  //
+public final class Config {
+
+  @Nullable
+  private final Context context;
+
+  // primitive flags
+  @ExtensionRendererMode final int extensionMode;
+
+  // NonNull options
+  @NonNull final BaseMeter meter;
+  @NonNull final LoadControl loadControl;
+  @NonNull final MediaSourceBuilder mediaSourceBuilder;
+
+  // Nullable options
+  @Nullable final DrmSessionManager<FrameworkMediaCrypto> drmSessionManager;
+  @Nullable final Cache cache; // null by default
+  // If null, ExoCreator must come up with a default one.
+  // This is to help customizing the Data source, for example using OkHttp extension.
+  @Nullable final DataSource.Factory dataSourceFactory;
+
+  @SuppressWarnings("WeakerAccess") //
+  Config(@Nullable Context context, int extensionMode, @NonNull BaseMeter meter,
+      @NonNull LoadControl loadControl,
+      @Nullable DataSource.Factory dataSourceFactory,
+      @NonNull MediaSourceBuilder mediaSourceBuilder,
+      @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager, @Nullable Cache cache) {
+    this.context = context != null ? context.getApplicationContext() : null;
+    this.extensionMode = extensionMode;
+    this.meter = meter;
+    this.loadControl = loadControl;
+    this.dataSourceFactory = dataSourceFactory;
+    this.mediaSourceBuilder = mediaSourceBuilder;
+    this.drmSessionManager = drmSessionManager;
+    this.cache = cache;
+  }
+
+  @Override public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+
+    Config config = (Config) o;
+
+    if (extensionMode != config.extensionMode) return false;
+    if (!meter.equals(config.meter)) return false;
+    if (!loadControl.equals(config.loadControl)) return false;
+    if (!mediaSourceBuilder.equals(config.mediaSourceBuilder)) return false;
+    if (!ObjectsCompat.equals(drmSessionManager, config.drmSessionManager)) return false;
+    if (!ObjectsCompat.equals(cache, config.cache)) return false;
+    return ObjectsCompat.equals(dataSourceFactory, config.dataSourceFactory);
+  }
+
+  @Override public int hashCode() {
+    int result = extensionMode;
+    result = 31 * result + meter.hashCode();
+    result = 31 * result + loadControl.hashCode();
+    result = 31 * result + mediaSourceBuilder.hashCode();
+    result = 31 * result + (drmSessionManager != null ? drmSessionManager.hashCode() : 0);
+    result = 31 * result + (cache != null ? cache.hashCode() : 0);
+    result = 31 * result + (dataSourceFactory != null ? dataSourceFactory.hashCode() : 0);
+    return result;
+  }
+
+  @SuppressWarnings("unused") public Builder newBuilder() {
+    return new Builder(context).setCache(this.cache)
+        .setDrmSessionManager(this.drmSessionManager)
+        .setExtensionMode(this.extensionMode)
+        .setLoadControl(this.loadControl)
+        .setMediaSourceBuilder(this.mediaSourceBuilder)
+        .setMeter(this.meter);
+  }
+
+  /// Builder
+  @SuppressWarnings({ "unused", "WeakerAccess" }) //
+  public static final class Builder {
+
+    @Nullable // only for backward compatibility
+    final Context context;
+
+    /**
+     * @deprecated Use the constructor with nonnull {@link Context} instead.
+     */
+    @Deprecated
+    public Builder() {
+      this(null);
+    }
+
+    public Builder(@Nullable Context context) {
+      this.context = context != null ? context.getApplicationContext() : null;
+      DefaultBandwidthMeter bandwidthMeter =
+          new DefaultBandwidthMeter.Builder(this.context).build();
+      meter = new BaseMeter<>(bandwidthMeter);
+    }
+
+    @ExtensionRendererMode private int extensionMode = EXTENSION_RENDERER_MODE_OFF;
+    private BaseMeter meter;
+    private LoadControl loadControl = new DefaultLoadControl();
+    private DataSource.Factory dataSourceFactory = null;
+    private MediaSourceBuilder mediaSourceBuilder = MediaSourceBuilder.DEFAULT;
+    private DrmSessionManager<FrameworkMediaCrypto> drmSessionManager = null;
+    private Cache cache = null;
+
+    public Builder setExtensionMode(@ExtensionRendererMode int extensionMode) {
+      this.extensionMode = extensionMode;
+      return this;
+    }
+
+    public Builder setMeter(@NonNull BaseMeter meter) {
+      this.meter = checkNotNull(meter, "Need non-null BaseMeter");
+      return this;
+    }
+
+    public Builder setLoadControl(@NonNull LoadControl loadControl) {
+      this.loadControl = checkNotNull(loadControl, "Need non-null LoadControl");
+      return this;
+    }
+
+    // Option is Nullable, but if user customize this, it must be a Nonnull one.
+    public Builder setDataSourceFactory(@NonNull DataSource.Factory dataSourceFactory) {
+      this.dataSourceFactory = checkNotNull(dataSourceFactory);
+      return this;
+    }
+
+    public Builder setMediaSourceBuilder(@NonNull MediaSourceBuilder mediaSourceBuilder) {
+      this.mediaSourceBuilder =
+          checkNotNull(mediaSourceBuilder, "Need non-null MediaSourceBuilder");
+      return this;
+    }
+
+    @Beta //
+    public Builder setDrmSessionManager(
+        @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager) {
+      this.drmSessionManager = drmSessionManager;
+      return this;
+    }
+
+    public Builder setCache(@Nullable Cache cache) {
+      this.cache = cache;
+      return this;
+    }
+
+    public Config build() {
+      return new Config(context, extensionMode, meter, loadControl, dataSourceFactory,
+          mediaSourceBuilder, drmSessionManager, cache);
+    }
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/DefaultExoCreator.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/DefaultExoCreator.java
new file mode 100644
index 00000000..af3bbd84
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/DefaultExoCreator.java
@@ -0,0 +1,193 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroExo.with;
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.checkNotNull;
+
+import android.content.Context;
+import android.net.Uri;
+import android.os.Handler;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.DefaultRenderersFactory;
+import com.google.android.exoplayer2.LoadControl;
+import com.google.android.exoplayer2.RenderersFactory;
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.source.MediaSourceEventListener;
+import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
+import com.google.android.exoplayer2.trackselection.TrackSelector;
+import com.google.android.exoplayer2.upstream.DataSource;
+import com.google.android.exoplayer2.upstream.DefaultBandwidthMeter;
+import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory;
+import com.google.android.exoplayer2.upstream.DefaultHttpDataSourceFactory;
+import com.google.android.exoplayer2.upstream.cache.CacheDataSourceFactory;
+import com.google.android.exoplayer2.util.Util;
+
+import java.io.IOException;
+
+/**
+ * Usage: use this as-it or inheritance.
+ *
+ * @author eneim (2018/02/04).
+ * @since 3.4.0
+ */
+
+@SuppressWarnings({ "unused", "WeakerAccess" }) //
+public class DefaultExoCreator implements ExoCreator, MediaSourceEventListener {
+
+  final ToroExo toro;  // per application
+  final Config config;
+  private final TrackSelector trackSelector;  // 'maybe' stateless
+  private final LoadControl loadControl;  // stateless
+  private final MediaSourceBuilder mediaSourceBuilder;  // stateless
+  private final RenderersFactory renderersFactory;  // stateless
+  private final DataSource.Factory mediaDataSourceFactory;  // stateless
+  private final DataSource.Factory manifestDataSourceFactory; // stateless
+
+  public DefaultExoCreator(@NonNull ToroExo toro, @NonNull Config config) {
+    this.toro = checkNotNull(toro);
+    this.config = checkNotNull(config);
+    trackSelector = new DefaultTrackSelector();
+    loadControl = config.loadControl;
+    mediaSourceBuilder = config.mediaSourceBuilder;
+
+    DefaultRenderersFactory tempFactory = new DefaultRenderersFactory(this.toro.context);
+    tempFactory.setExtensionRendererMode(config.extensionMode);
+    renderersFactory = tempFactory;
+
+    DataSource.Factory baseFactory = config.dataSourceFactory;
+    if (baseFactory == null) {
+      baseFactory = new DefaultHttpDataSourceFactory(toro.appName, config.meter);
+    }
+    DataSource.Factory factory = new DefaultDataSourceFactory(this.toro.context,  //
+        config.meter, baseFactory);
+    if (config.cache != null) factory = new CacheDataSourceFactory(config.cache, factory);
+    mediaDataSourceFactory = factory;
+    manifestDataSourceFactory = new DefaultDataSourceFactory(this.toro.context, this.toro.appName);
+  }
+
+  public DefaultExoCreator(Context context, Config config) {
+    this(with(context), config);
+  }
+
+  @SuppressWarnings("SimplifiableIfStatement")
+  @Override public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+
+    DefaultExoCreator that = (DefaultExoCreator) o;
+
+    if (!toro.equals(that.toro)) return false;
+    if (!trackSelector.equals(that.trackSelector)) return false;
+    if (!loadControl.equals(that.loadControl)) return false;
+    if (!mediaSourceBuilder.equals(that.mediaSourceBuilder)) return false;
+    if (!renderersFactory.equals(that.renderersFactory)) return false;
+    if (!mediaDataSourceFactory.equals(that.mediaDataSourceFactory)) return false;
+    return manifestDataSourceFactory.equals(that.manifestDataSourceFactory);
+  }
+
+  @Override public int hashCode() {
+    int result = toro.hashCode();
+    result = 31 * result + trackSelector.hashCode();
+    result = 31 * result + loadControl.hashCode();
+    result = 31 * result + mediaSourceBuilder.hashCode();
+    result = 31 * result + renderersFactory.hashCode();
+    result = 31 * result + mediaDataSourceFactory.hashCode();
+    result = 31 * result + manifestDataSourceFactory.hashCode();
+    return result;
+  }
+
+  final TrackSelector getTrackSelector() {
+    return trackSelector;
+  }
+
+  @Nullable @Override public Context getContext() {
+    return toro.context;
+  }
+
+  @NonNull @Override public SimpleExoPlayer createPlayer() {
+    return new ToroExoPlayer(toro.context, renderersFactory, trackSelector, loadControl,
+        new DefaultBandwidthMeter.Builder(toro.context).build(), config.drmSessionManager,
+        Util.getLooper());
+  }
+
+  @NonNull @Override public MediaSource createMediaSource(@NonNull Uri uri, String fileExt) {
+    return mediaSourceBuilder.buildMediaSource(this.toro.context, uri, fileExt, new Handler(),
+        manifestDataSourceFactory, mediaDataSourceFactory, this);
+  }
+
+  @NonNull @Override //
+  public Playable createPlayable(@NonNull Uri uri, String fileExt) {
+    return new PlayableImpl(this, uri, fileExt);
+  }
+
+  /// MediaSourceEventListener
+
+  @Override
+  public void onLoadStarted(int windowIndex, @Nullable MediaSource.MediaPeriodId mediaPeriodId,
+      LoadEventInfo loadEventInfo, MediaLoadData mediaLoadData) {
+    // no-ops
+  }
+
+  @Override
+  public void onLoadCompleted(int windowIndex, @Nullable MediaSource.MediaPeriodId mediaPeriodId,
+      LoadEventInfo loadEventInfo, MediaLoadData mediaLoadData) {
+    // no-ops
+  }
+
+  @Override
+  public void onLoadCanceled(int windowIndex, @Nullable MediaSource.MediaPeriodId mediaPeriodId,
+      LoadEventInfo loadEventInfo, MediaLoadData mediaLoadData) {
+    // no-ops
+  }
+
+  @Override
+  public void onLoadError(int windowIndex, @Nullable MediaSource.MediaPeriodId mediaPeriodId,
+      LoadEventInfo loadEventInfo, MediaLoadData mediaLoadData, IOException error,
+      boolean wasCanceled) {
+    // no-ops
+  }
+
+  @Override public void onReadingStarted(int windowIndex, MediaSource.MediaPeriodId mediaPeriodId) {
+    // no-ops
+  }
+
+  @Override
+  public void onUpstreamDiscarded(int windowIndex, MediaSource.MediaPeriodId mediaPeriodId,
+      MediaLoadData mediaLoadData) {
+    // no-ops
+  }
+
+  @Override public void onDownstreamFormatChanged(int windowIndex,
+      @Nullable MediaSource.MediaPeriodId mediaPeriodId, MediaLoadData mediaLoadData) {
+    // no-ops
+  }
+
+  @Override
+  public void onMediaPeriodCreated(int windowIndex, MediaSource.MediaPeriodId mediaPeriodId) {
+    // no-ops
+  }
+
+  @Override
+  public void onMediaPeriodReleased(int windowIndex, MediaSource.MediaPeriodId mediaPeriodId) {
+    // no-ops
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoCreator.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoCreator.java
new file mode 100644
index 00000000..c4319493
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoCreator.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import android.content.Context;
+import android.net.Uri;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.source.MediaSource;
+
+/**
+ * A simple interface whose implementation helps Client to easily create {@link SimpleExoPlayer}
+ * instance, {@link MediaSource} instance or specifically a {@link Playable} instance.
+ *
+ * Most of the time, Client just needs to request for a {@link Playable} for a specific Uri.
+ *
+ * @author eneim (2018/02/04).
+ * @since 3.4.0
+ */
+
+public interface ExoCreator {
+
+  String TAG = "ToroExo:Creator";
+
+  /**
+   * Return current Application context used in {@link ToroExo}. An {@link ExoCreator} must be used
+   * within Application scope.
+   */
+  @Nullable Context getContext();
+
+  /**
+   * Create a new {@link SimpleExoPlayer} instance. This method should always create new instance of
+   * {@link SimpleExoPlayer}, but client should use {@link ExoCreator} indirectly via
+   * {@link ToroExo}.
+   *
+   * @return a new {@link SimpleExoPlayer} instance.
+   */
+  @NonNull SimpleExoPlayer createPlayer();
+
+  /**
+   * Create a {@link MediaSource} from media {@link Uri}.
+   *
+   * @param uri the media {@link Uri}.
+   * @param fileExt the optional (File) extension of the media Uri.
+   * @return a {@link MediaSource} for media {@link Uri}.
+   */
+  @NonNull MediaSource createMediaSource(@NonNull Uri uri, @Nullable String fileExt);
+
+  // Client just needs the method below to work with Toro, but I prepare both 2 above for custom use-cases.
+
+  /**
+   * Create a {@link Playable} for a media {@link Uri}. Client should always use this method for
+   * quick and simple setup. Only use {@link #createMediaSource(Uri, String)} and/or
+   * {@link #createPlayer()} when necessary.
+   *
+   * @param uri the media {@link Uri}.
+   * @param fileExt the optional (File) extension of the media Uri.
+   * @return the {@link Playable} to manage the media {@link Uri}.
+   */
+  @NonNull
+  Playable createPlayable(@NonNull Uri uri, @Nullable String fileExt);
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayable.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayable.java
new file mode 100644
index 00000000..a159ea17
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayable.java
@@ -0,0 +1,205 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static com.google.android.exoplayer2.trackselection.MappingTrackSelector.MappedTrackInfo.RENDERER_SUPPORT_UNSUPPORTED_TRACKS;
+
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroExo.toro;
+
+import android.net.Uri;
+import android.widget.Toast;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.ExoPlaybackException;
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.mediacodec.MediaCodecRenderer;
+import com.google.android.exoplayer2.mediacodec.MediaCodecUtil;
+import com.google.android.exoplayer2.source.BehindLiveWindowException;
+import com.google.android.exoplayer2.source.TrackGroupArray;
+import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
+import com.google.android.exoplayer2.trackselection.MappingTrackSelector.MappedTrackInfo;
+import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
+import com.google.android.exoplayer2.trackselection.TrackSelector;
+import com.google.android.exoplayer2.ui.PlayerView;
+
+import ml.docilealligator.infinityforreddit.R;
+
+/**
+ * Making {@link Playable} extensible. This can be used with custom {@link ExoCreator}. Extending
+ * this class must make sure the re-usability of the implementation.
+ *
+ * @author eneim (2018/02/26).
+ * @since 3.4.0
+ */
+
+@SuppressWarnings("WeakerAccess")
+public class ExoPlayable extends PlayableImpl {
+
+  @SuppressWarnings("unused") private static final String TAG = "ToroExo:Playable";
+
+  private EventListener listener;
+
+  // Adapt from ExoPlayer demo.
+  protected boolean inErrorState = false;
+  protected TrackGroupArray lastSeenTrackGroupArray;
+
+  /**
+   * Construct an instance of {@link ExoPlayable} from an {@link ExoCreator} and {@link Uri}. The
+   * {@link ExoCreator} is used to request {@link SimpleExoPlayer} instance, while {@link Uri}
+   * defines the media to play.
+   *
+   * @param creator the {@link ExoCreator} instance.
+   * @param uri the {@link Uri} of the media.
+   * @param fileExt the custom extension of the media Uri.
+   */
+  public ExoPlayable(ExoCreator creator, Uri uri, String fileExt) {
+    super(creator, uri, fileExt);
+  }
+
+  @Override public void prepare(boolean prepareSource) {
+    if (listener == null) {
+      listener = new Listener();
+      super.addEventListener(listener);
+    }
+    super.prepare(prepareSource);
+    this.lastSeenTrackGroupArray = null;
+    this.inErrorState = false;
+  }
+
+  @Override public void setPlayerView(@Nullable PlayerView playerView) {
+    // This will also clear these flags
+    if (playerView != this.playerView) {
+      this.lastSeenTrackGroupArray = null;
+      this.inErrorState = false;
+    }
+    super.setPlayerView(playerView);
+  }
+
+  @Override public void reset() {
+    super.reset();
+    this.lastSeenTrackGroupArray = null;
+    this.inErrorState = false;
+  }
+
+  @Override public void release() {
+    if (listener != null) {
+      super.removeEventListener(listener);
+      listener = null;
+    }
+    super.release();
+    this.lastSeenTrackGroupArray = null;
+    this.inErrorState = false;
+  }
+
+  @SuppressWarnings({ "unused" }) //
+  protected void onErrorMessage(@NonNull String message) {
+    // Sub class can have custom reaction about the error here, including not to show this toast
+    // (by not calling super.onErrorMessage(message)).
+    if (this.errorListeners.size() > 0) {
+      this.errorListeners.onError(new RuntimeException(message));
+    } else if (playerView != null) {
+      Toast.makeText(playerView.getContext(), message, Toast.LENGTH_SHORT).show();
+    }
+  }
+
+  class Listener extends DefaultEventListener {
+
+    @Override
+    public void onTracksChanged(TrackGroupArray trackGroups, TrackSelectionArray trackSelections) {
+      super.onTracksChanged(trackGroups, trackSelections);
+      if (trackGroups == lastSeenTrackGroupArray) return;
+      lastSeenTrackGroupArray = trackGroups;
+      if (!(creator instanceof DefaultExoCreator)) return;
+      TrackSelector selector = ((DefaultExoCreator) creator).getTrackSelector();
+      if (selector instanceof DefaultTrackSelector) {
+        MappedTrackInfo trackInfo = ((DefaultTrackSelector) selector).getCurrentMappedTrackInfo();
+        if (trackInfo != null) {
+          if (trackInfo.getTypeSupport(C.TRACK_TYPE_VIDEO) == RENDERER_SUPPORT_UNSUPPORTED_TRACKS) {
+            onErrorMessage(toro.getString(R.string.error_unsupported_video));
+          }
+
+          if (trackInfo.getTypeSupport(C.TRACK_TYPE_AUDIO) == RENDERER_SUPPORT_UNSUPPORTED_TRACKS) {
+            onErrorMessage(toro.getString(R.string.error_unsupported_audio));
+          }
+        }
+      }
+    }
+
+    @Override public void onPlayerError(ExoPlaybackException error) {
+      /// Adapt from ExoPlayer Demo
+      String errorString = null;
+      if (error.type == ExoPlaybackException.TYPE_RENDERER) {
+        Exception cause = error.getRendererException();
+        if (cause instanceof MediaCodecRenderer.DecoderInitializationException) {
+          // Special case for decoder initialization failures.
+          MediaCodecRenderer.DecoderInitializationException decoderInitializationException =
+              (MediaCodecRenderer.DecoderInitializationException) cause;
+          if (decoderInitializationException.decoderName == null) {
+            if (decoderInitializationException.getCause() instanceof MediaCodecUtil.DecoderQueryException) {
+              errorString = toro.getString(R.string.error_querying_decoders);
+            } else if (decoderInitializationException.secureDecoderRequired) {
+              errorString = toro.getString(R.string.error_no_secure_decoder,
+                  decoderInitializationException.mimeType);
+            } else {
+              errorString = toro.getString(R.string.error_no_decoder,
+                  decoderInitializationException.mimeType);
+            }
+          } else {
+            errorString = toro.getString(R.string.error_instantiating_decoder,
+                decoderInitializationException.decoderName);
+          }
+        }
+      }
+
+      if (errorString != null) onErrorMessage(errorString);
+
+      inErrorState = true;
+      if (isBehindLiveWindow(error)) {
+        ExoPlayable.super.reset();
+      } else {
+        ExoPlayable.super.updatePlaybackInfo();
+      }
+
+      super.onPlayerError(error);
+    }
+
+    @Override public void onPositionDiscontinuity(int reason) {
+      if (inErrorState) {
+        // Adapt from ExoPlayer demo.
+        // "This will only occur if the user has performed a seek whilst in the error state. Update
+        // the resume position so that if the user then retries, playback will resume from the
+        // position to which they seek." - ExoPlayer
+        ExoPlayable.super.updatePlaybackInfo();
+      }
+
+      super.onPositionDiscontinuity(reason);
+    }
+  }
+
+  static boolean isBehindLiveWindow(ExoPlaybackException error) {
+    if (error.type != ExoPlaybackException.TYPE_SOURCE) return false;
+    Throwable cause = error.getSourceException();
+    while (cause != null) {
+      if (cause instanceof BehindLiveWindowException) return true;
+      cause = cause.getCause();
+    }
+    return false;
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayerDispatcher.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayerDispatcher.java
new file mode 100644
index 00000000..031c1f3a
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayerDispatcher.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import com.google.android.exoplayer2.DefaultControlDispatcher;
+import com.google.android.exoplayer2.Player;
+import com.google.android.exoplayer2.ui.PlayerView;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.Beta;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.PressablePlayerSelector;
+
+/**
+ * @author eneim (2018/08/18).
+ * @since 3.6.0.2802
+ *
+ * Work with {@link PressablePlayerSelector} and {@link PlayerView} to handle user's custom playback
+ * interaction. A common use-case is when user clicks the Play button to manually start a playback.
+ * We should respect this by putting the {@link ToroPlayer}'s priority to highest, and request a
+ * refresh for all {@link ToroPlayer}.
+ *
+ * The same behaviour should be handled for the case user clicks the Pause button.
+ *
+ * All behaviour should be cleared once user scroll the selection out of playable region. This is
+ * already handled by {@link PressablePlayerSelector}.
+ */
+@Beta //
+public class ExoPlayerDispatcher extends DefaultControlDispatcher {
+
+  private final PressablePlayerSelector playerSelector;
+  private final ToroPlayer toroPlayer;
+
+  public ExoPlayerDispatcher(PressablePlayerSelector playerSelector, ToroPlayer toroPlayer) {
+    this.playerSelector = playerSelector;
+    this.toroPlayer = toroPlayer;
+  }
+
+  @Override public boolean dispatchSetPlayWhenReady(Player player, boolean playWhenReady) {
+    if (playWhenReady) {
+      // Container will handle the call to play.
+      return playerSelector.toPlay(toroPlayer.getPlayerOrder());
+    } else {
+      player.setPlayWhenReady(false);
+      playerSelector.toPause(toroPlayer.getPlayerOrder());
+      return true;
+    }
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayerViewHelper.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayerViewHelper.java
new file mode 100644
index 00000000..3ee611a7
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ExoPlayerViewHelper.java
@@ -0,0 +1,171 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroExo.with;
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.checkNotNull;
+
+import android.net.Uri;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.ExoPlayer;
+import com.google.android.exoplayer2.ui.PlayerView;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.RemoveIn;
+import ml.docilealligator.infinityforreddit.videoautoplay.helper.ToroPlayerHelper;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
+
+/**
+ * An implementation of {@link ToroPlayerHelper} where the actual Player is an {@link ExoPlayer}
+ * implementation. This is a bridge between ExoPlayer's callback and ToroPlayerHelper behaviors.
+ *
+ * @author eneim (2018/01/24).
+ * @since 3.4.0
+ */
+
+public class ExoPlayerViewHelper extends ToroPlayerHelper {
+
+  @NonNull private final ExoPlayable playable;
+  @NonNull private final MyEventListeners listeners;
+  private final boolean lazyPrepare;
+
+  // Container is no longer required for constructing new instance.
+  @SuppressWarnings("unused") @RemoveIn(version = "3.6.0") @Deprecated  //
+  public ExoPlayerViewHelper(Container container, @NonNull ToroPlayer player, @NonNull Uri uri) {
+    this(player, uri);
+  }
+
+  public ExoPlayerViewHelper(@NonNull ToroPlayer player, @NonNull Uri uri) {
+    this(player, uri, null);
+  }
+
+  public ExoPlayerViewHelper(@NonNull ToroPlayer player, @NonNull Uri uri,
+      @Nullable String fileExt) {
+    this(player, uri, fileExt, with(player.getPlayerView().getContext()).getDefaultCreator());
+  }
+
+  /** Config instance should be kept as global instance. */
+  public ExoPlayerViewHelper(@NonNull ToroPlayer player, @NonNull Uri uri, @Nullable String fileExt,
+      @NonNull Config config) {
+    this(player, uri, fileExt,
+        with(player.getPlayerView().getContext()).getCreator(checkNotNull(config)));
+  }
+
+  public ExoPlayerViewHelper(@NonNull ToroPlayer player, @NonNull Uri uri, @Nullable String fileExt,
+      @NonNull ExoCreator creator) {
+    this(player, new ExoPlayable(creator, uri, fileExt));
+  }
+
+  public ExoPlayerViewHelper(@NonNull ToroPlayer player, @NonNull ExoPlayable playable) {
+    super(player);
+    //noinspection ConstantConditions
+    if (player.getPlayerView() == null || !(player.getPlayerView() instanceof PlayerView)) {
+      throw new IllegalArgumentException("Require non-null PlayerView");
+    }
+
+    listeners = new MyEventListeners();
+    this.playable = playable;
+    this.lazyPrepare = true;
+  }
+
+  @Override protected void initialize(@NonNull PlaybackInfo playbackInfo) {
+    playable.setPlaybackInfo(playbackInfo);
+    playable.addEventListener(listeners);
+    playable.addErrorListener(super.getErrorListeners());
+    playable.addOnVolumeChangeListener(super.getVolumeChangeListeners());
+    playable.prepare(!lazyPrepare);
+    playable.setPlayerView((PlayerView) player.getPlayerView());
+  }
+
+  @Override public void release() {
+    super.release();
+    playable.setPlayerView(null);
+    playable.removeOnVolumeChangeListener(super.getVolumeChangeListeners());
+    playable.removeErrorListener(super.getErrorListeners());
+    playable.removeEventListener(listeners);
+    playable.release();
+  }
+
+  @Override public void play() {
+    playable.play();
+  }
+
+  @Override public void pause() {
+    playable.pause();
+  }
+
+  @Override public boolean isPlaying() {
+    return playable.isPlaying();
+  }
+
+  @Override public void setVolume(float volume) {
+    playable.setVolume(volume);
+  }
+
+  @Override public float getVolume() {
+    return playable.getVolume();
+  }
+
+  @Override public void setVolumeInfo(@NonNull VolumeInfo volumeInfo) {
+    playable.setVolumeInfo(volumeInfo);
+  }
+
+  @Override @NonNull public VolumeInfo getVolumeInfo() {
+    return playable.getVolumeInfo();
+  }
+
+  @NonNull @Override public PlaybackInfo getLatestPlaybackInfo() {
+    return playable.getPlaybackInfo();
+  }
+
+  @Override public void setPlaybackInfo(@NonNull PlaybackInfo playbackInfo) {
+    this.playable.setPlaybackInfo(playbackInfo);
+  }
+
+  public void addEventListener(@NonNull Playable.EventListener listener) {
+    //noinspection ConstantConditions
+    if (listener != null) this.listeners.add(listener);
+  }
+
+  public void removeEventListener(Playable.EventListener listener) {
+    this.listeners.remove(listener);
+  }
+
+  // A proxy, to also hook into ToroPlayerHelper's state change event.
+  private class MyEventListeners extends Playable.EventListeners {
+
+    MyEventListeners() {
+    }
+
+    @Override public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
+      ExoPlayerViewHelper.super.onPlayerStateUpdated(playWhenReady, playbackState); // important
+      super.onPlayerStateChanged(playWhenReady, playbackState);
+    }
+
+    @Override public void onRenderedFirstFrame() {
+      super.onRenderedFirstFrame();
+      internalListener.onFirstFrameRendered();
+      for (ToroPlayer.EventListener listener : ExoPlayerViewHelper.super.getEventListeners()) {
+        listener.onFirstFrameRendered();
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/MediaSourceBuilder.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/MediaSourceBuilder.java
new file mode 100644
index 00000000..7daacc99
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/MediaSourceBuilder.java
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static android.text.TextUtils.isEmpty;
+import static com.google.android.exoplayer2.util.Util.inferContentType;
+
+import android.content.Context;
+import android.net.Uri;
+import android.os.Handler;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.C.ContentType;
+import com.google.android.exoplayer2.source.LoopingMediaSource;
+import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.source.MediaSourceEventListener;
+import com.google.android.exoplayer2.source.ProgressiveMediaSource;
+import com.google.android.exoplayer2.source.dash.DashMediaSource;
+import com.google.android.exoplayer2.source.dash.DefaultDashChunkSource;
+import com.google.android.exoplayer2.source.hls.HlsMediaSource;
+import com.google.android.exoplayer2.upstream.DataSource;
+
+/**
+ * @author eneim (2018/01/24).
+ * @since 3.4.0
+ */
+
+public interface MediaSourceBuilder {
+
+  @NonNull MediaSource buildMediaSource(@NonNull Context context, @NonNull Uri uri,
+      @Nullable String fileExt, @Nullable Handler handler,
+      @NonNull DataSource.Factory manifestDataSourceFactory,
+      @NonNull DataSource.Factory mediaDataSourceFactory,
+      @Nullable MediaSourceEventListener listener);
+
+  MediaSourceBuilder DEFAULT = new MediaSourceBuilder() {
+    @NonNull @Override
+    public MediaSource buildMediaSource(@NonNull Context context, @NonNull Uri uri,
+        @Nullable String ext, @Nullable Handler handler,
+        @NonNull DataSource.Factory manifestDataSourceFactory,
+        @NonNull DataSource.Factory mediaDataSourceFactory, MediaSourceEventListener listener) {
+      @ContentType int type = isEmpty(ext) ? inferContentType(uri) : inferContentType("." + ext);
+      MediaSource result;
+      switch (type) {
+        /*case C.TYPE_SS:
+          result = new SsMediaSource.Factory( //
+              new DefaultSsChunkSource.Factory(mediaDataSourceFactory), manifestDataSourceFactory)//
+              .createMediaSource(uri);
+          break;*/
+        case C.TYPE_DASH:
+          result = new DashMediaSource.Factory(
+              new DefaultDashChunkSource.Factory(mediaDataSourceFactory), manifestDataSourceFactory)
+              .createMediaSource(uri);
+          break;
+        case C.TYPE_HLS:
+          result = new HlsMediaSource.Factory(mediaDataSourceFactory) //
+              .createMediaSource(uri);
+          break;
+        case C.TYPE_OTHER:
+          result = new ProgressiveMediaSource.Factory(mediaDataSourceFactory) //
+              .createMediaSource(uri);
+          break;
+        default:
+          throw new IllegalStateException("Unsupported type: " + type);
+      }
+
+      result.addEventListener(handler, listener);
+      return result;
+    }
+  };
+
+  MediaSourceBuilder LOOPING = new MediaSourceBuilder() {
+
+    @NonNull @Override
+    public MediaSource buildMediaSource(@NonNull Context context, @NonNull Uri uri,
+        @Nullable String fileExt, @Nullable Handler handler,
+        @NonNull DataSource.Factory manifestDataSourceFactory,
+        @NonNull DataSource.Factory mediaDataSourceFactory,
+        @Nullable MediaSourceEventListener listener) {
+      return new LoopingMediaSource(
+          DEFAULT.buildMediaSource(context, uri, fileExt, handler, manifestDataSourceFactory,
+              mediaDataSourceFactory, listener));
+    }
+  };
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/Playable.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/Playable.java
new file mode 100644
index 00000000..a713b5a7
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/Playable.java
@@ -0,0 +1,365 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import androidx.annotation.FloatRange;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.ExoPlaybackException;
+import com.google.android.exoplayer2.PlaybackParameters;
+import com.google.android.exoplayer2.Player;
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.Timeline;
+import com.google.android.exoplayer2.metadata.Metadata;
+import com.google.android.exoplayer2.metadata.MetadataOutput;
+import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.source.TrackGroupArray;
+import com.google.android.exoplayer2.text.Cue;
+import com.google.android.exoplayer2.text.TextOutput;
+import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
+import com.google.android.exoplayer2.ui.PlayerView;
+import com.google.android.exoplayer2.video.VideoListener;
+
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArraySet;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.RemoveIn;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
+
+/**
+ * Define an interface to control a playback, specific for {@link SimpleExoPlayer} and {@link PlayerView}.
+ *
+ * This interface is designed to be reused across Config change. Implementation must not hold any
+ * strong reference to Activity, and if it supports any kind of that, make sure to implicitly clean
+ * it up.
+ *
+ * @author eneim
+ * @since 3.4.0
+ */
+
+@SuppressWarnings("unused") //
+public interface Playable {
+
+  /**
+   * Prepare the resource for a {@link SimpleExoPlayer}. This method should:
+   * - Request for new {@link SimpleExoPlayer} instance if there is not a usable one.
+   * - Configure {@link EventListener} for it.
+   * - If there is non-trivial PlaybackInfo, update it to the SimpleExoPlayer.
+   * - If client request to prepare MediaSource, then prepare it.
+   *
+   * This method must be called before {@link #setPlayerView(PlayerView)}.
+   *
+   * @param prepareSource if {@code true}, also prepare the MediaSource when preparing the Player,
+   * if {@code false} just do nothing for the MediaSource.
+   */
+  void prepare(boolean prepareSource);
+
+  /**
+   * Set the {@link PlayerView} for this Playable. It is expected that a playback doesn't require a
+   * UI, so this setup is optional. But it must be called after the SimpleExoPlayer is prepared,
+   * that is after {@link #prepare(boolean)} and before {@link #release()}.
+   *
+   * Changing the PlayerView during playback is expected, though not always recommended, especially
+   * on old Devices with low Android API.
+   *
+   * @param playerView the PlayerView to set to the SimpleExoPlayer.
+   */
+  void setPlayerView(@Nullable PlayerView playerView);
+
+  /**
+   * Get current {@link PlayerView} of this Playable.
+   *
+   * @return current PlayerView instance of this Playable.
+   */
+  @Nullable PlayerView getPlayerView();
+
+  /**
+   * Start the playback. If the {@link MediaSource} is not prepared, then also prepare it.
+   */
+  void play();
+
+  /**
+   * Pause the playback.
+   */
+  void pause();
+
+  /**
+   * Reset all resource, so that the playback can start all over again. This is to cleanup the
+   * playback for reuse. The SimpleExoPlayer instance must be still usable without calling
+   * {@link #prepare(boolean)}.
+   */
+  void reset();
+
+  /**
+   * Release all resource. After this, the SimpleExoPlayer is released to the Player pool and the
+   * Playable must call {@link #prepare(boolean)} again to use it again.
+   */
+  void release();
+
+  /**
+   * Get current {@link PlaybackInfo} of the playback.
+   *
+   * @return current PlaybackInfo of the playback.
+   */
+  @NonNull
+  PlaybackInfo getPlaybackInfo();
+
+  /**
+   * Set the custom {@link PlaybackInfo} for this playback. This could suggest a seek.
+   *
+   * @param playbackInfo the PlaybackInfo to set for this playback.
+   */
+  void setPlaybackInfo(@NonNull PlaybackInfo playbackInfo);
+
+  /**
+   * Add a new {@link EventListener} to this Playable. As calling {@link #prepare(boolean)} also
+   * triggers some internal events, this method should be called before {@link #prepare(boolean)} so
+   * that Client could received them all.
+   *
+   * @param listener the EventListener to add, must be not {@code null}.
+   */
+  void addEventListener(@NonNull EventListener listener);
+
+  /**
+   * Remove an {@link EventListener} from this Playable.
+   *
+   * @param listener the EventListener to be removed. If null, nothing happens.
+   */
+  void removeEventListener(EventListener listener);
+
+  /**
+   * !This must only work if the Player in use is a {@link ToroExoPlayer}.
+   */
+  void addOnVolumeChangeListener(@NonNull ToroPlayer.OnVolumeChangeListener listener);
+
+  void removeOnVolumeChangeListener(@Nullable ToroPlayer.OnVolumeChangeListener listener);
+
+  /**
+   * Check if current Playable is playing or not.
+   *
+   * @return {@code true} if this Playable is playing, {@code false} otherwise.
+   */
+  boolean isPlaying();
+
+  /**
+   * Change the volume of current playback.
+   *
+   * @param volume the volume value to be set. Must be a {@code float} of range from 0 to 1.
+   * @deprecated use {@link #setVolumeInfo(VolumeInfo)} instead.
+   */
+  @RemoveIn(version = "3.6.0") @Deprecated  //
+  void setVolume(@FloatRange(from = 0.0, to = 1.0) float volume);
+
+  /**
+   * Obtain current volume value. The returned value is a {@code float} of range from 0 to 1.
+   *
+   * @return current volume value.
+   * @deprecated use {@link #getVolumeInfo()} instead.
+   */
+  @RemoveIn(version = "3.6.0") @Deprecated  //
+  @FloatRange(from = 0.0, to = 1.0) float getVolume();
+
+  /**
+   * Update playback's volume.
+   *
+   * @param volumeInfo the {@link VolumeInfo} to update to.
+   * @return {@code true} if current Volume info is updated, {@code false} otherwise.
+   */
+  boolean setVolumeInfo(@NonNull VolumeInfo volumeInfo);
+
+  /**
+   * Get current {@link VolumeInfo}.
+   */
+  @NonNull VolumeInfo getVolumeInfo();
+
+  /**
+   * Same as {@link Player#setPlaybackParameters(PlaybackParameters)}
+   */
+  void setParameters(@Nullable PlaybackParameters parameters);
+
+  /**
+   * Same as {@link Player#getPlaybackParameters()}
+   */
+  @Nullable PlaybackParameters getParameters();
+
+  void addErrorListener(@NonNull ToroPlayer.OnErrorListener listener);
+
+  void removeErrorListener(@Nullable ToroPlayer.OnErrorListener listener);
+
+  // Combine necessary interfaces.
+  interface EventListener extends Player.EventListener, VideoListener, TextOutput, MetadataOutput {
+
+  }
+
+  /** Default empty implementation */
+  class DefaultEventListener implements EventListener {
+
+    @Override public void onTimelineChanged(Timeline timeline, Object manifest, int reason) {
+
+    }
+
+    @Override
+    public void onTracksChanged(TrackGroupArray trackGroups, TrackSelectionArray trackSelections) {
+
+    }
+
+    @Override public void onLoadingChanged(boolean isLoading) {
+
+    }
+
+    @Override public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
+
+    }
+
+    @Override public void onRepeatModeChanged(int repeatMode) {
+
+    }
+
+    @Override public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+
+    }
+
+    @Override public void onPlayerError(ExoPlaybackException error) {
+
+    }
+
+    @Override public void onPositionDiscontinuity(int reason) {
+
+    }
+
+    @Override public void onPlaybackParametersChanged(PlaybackParameters playbackParameters) {
+
+    }
+
+    @Override public void onSeekProcessed() {
+
+    }
+
+    @Override public void onVideoSizeChanged(int width, int height, int unappliedRotationDegrees,
+        float pixelWidthHeightRatio) {
+
+    }
+
+    @Override public void onRenderedFirstFrame() {
+
+    }
+
+    @Override public void onCues(List<Cue> cues) {
+
+    }
+
+    @Override public void onMetadata(Metadata metadata) {
+
+    }
+  }
+
+  /** List of EventListener */
+  class EventListeners extends CopyOnWriteArraySet<EventListener> implements EventListener {
+
+    EventListeners() {
+    }
+
+    @Override public void onVideoSizeChanged(int width, int height, int unAppliedRotationDegrees,
+        float pixelWidthHeightRatio) {
+      for (EventListener eventListener : this) {
+        eventListener.onVideoSizeChanged(width, height, unAppliedRotationDegrees,
+            pixelWidthHeightRatio);
+      }
+    }
+
+    @Override public void onRenderedFirstFrame() {
+      for (EventListener eventListener : this) {
+        eventListener.onRenderedFirstFrame();
+      }
+    }
+
+    @Override public void onTimelineChanged(Timeline timeline, Object manifest, int reason) {
+      for (EventListener eventListener : this) {
+        eventListener.onTimelineChanged(timeline, manifest, reason);
+      }
+    }
+
+    @Override
+    public void onTracksChanged(TrackGroupArray trackGroups, TrackSelectionArray trackSelections) {
+      for (EventListener eventListener : this) {
+        eventListener.onTracksChanged(trackGroups, trackSelections);
+      }
+    }
+
+    @Override public void onLoadingChanged(boolean isLoading) {
+      for (EventListener eventListener : this) {
+        eventListener.onLoadingChanged(isLoading);
+      }
+    }
+
+    @Override public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
+      for (EventListener eventListener : this) {
+        eventListener.onPlayerStateChanged(playWhenReady, playbackState);
+      }
+    }
+
+    @Override public void onRepeatModeChanged(int repeatMode) {
+      for (EventListener eventListener : this) {
+        eventListener.onRepeatModeChanged(repeatMode);
+      }
+    }
+
+    @Override public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+      for (EventListener eventListener : this) {
+        eventListener.onShuffleModeEnabledChanged(shuffleModeEnabled);
+      }
+    }
+
+    @Override public void onPlayerError(ExoPlaybackException error) {
+      for (EventListener eventListener : this) {
+        eventListener.onPlayerError(error);
+      }
+    }
+
+    @Override public void onPositionDiscontinuity(int reason) {
+      for (EventListener eventListener : this) {
+        eventListener.onPositionDiscontinuity(reason);
+      }
+    }
+
+    @Override public void onPlaybackParametersChanged(PlaybackParameters playbackParameters) {
+      for (EventListener eventListener : this) {
+        eventListener.onPlaybackParametersChanged(playbackParameters);
+      }
+    }
+
+    @Override public void onSeekProcessed() {
+      for (EventListener eventListener : this) {
+        eventListener.onSeekProcessed();
+      }
+    }
+
+    @Override public void onCues(List<Cue> cues) {
+      for (EventListener eventListener : this) {
+        eventListener.onCues(cues);
+      }
+    }
+
+    @Override public void onMetadata(Metadata metadata) {
+      for (EventListener eventListener : this) {
+        eventListener.onMetadata(metadata);
+      }
+    }
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayableImpl.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayableImpl.java
new file mode 100644
index 00000000..d1d47c07
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayableImpl.java
@@ -0,0 +1,287 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroExo.with;
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.checkNotNull;
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.INDEX_UNSET;
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.TIME_UNSET;
+
+import android.net.Uri;
+
+import androidx.annotation.CallSuper;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.PlaybackParameters;
+import com.google.android.exoplayer2.Player;
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.ui.PlayerView;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
+
+/**
+ * [20180225]
+ *
+ * Default implementation of {@link Playable}.
+ *
+ * Instance of {@link Playable} should be reusable. Retaining instance of Playable across config
+ * change must guarantee that all {@link EventListener} are cleaned up on config change.
+ *
+ * @author eneim (2018/02/25).
+ */
+@SuppressWarnings("WeakerAccess") //
+class PlayableImpl implements Playable {
+
+  private final PlaybackInfo playbackInfo = new PlaybackInfo(); // never expose to outside.
+
+  protected final EventListeners listeners = new EventListeners();  // original listener.
+  protected final ToroPlayer.VolumeChangeListeners volumeChangeListeners = new ToroPlayer.VolumeChangeListeners();
+  protected final ToroPlayer.ErrorListeners errorListeners = new ToroPlayer.ErrorListeners();
+
+  protected final Uri mediaUri; // immutable, parcelable
+  protected final String fileExt;
+  protected final ExoCreator creator; // required, cached
+
+  protected SimpleExoPlayer player; // on-demand, cached
+  protected MediaSource mediaSource;  // on-demand, since we do not reuse MediaSource now.
+  protected PlayerView playerView; // on-demand, not always required.
+
+  private boolean sourcePrepared = false;
+  private boolean listenerApplied = false;
+
+  PlayableImpl(ExoCreator creator, Uri uri, String fileExt) {
+    this.creator = creator;
+    this.mediaUri = uri;
+    this.fileExt = fileExt;
+  }
+
+  @CallSuper @Override public void prepare(boolean prepareSource) {
+    if (prepareSource) {
+      ensureMediaSource();
+      ensurePlayerView();
+    }
+  }
+
+  @CallSuper @Override public void setPlayerView(@Nullable PlayerView playerView) {
+    if (this.playerView == playerView) return;
+    if (playerView == null) {
+      this.playerView.setPlayer(null);
+    } else {
+      if (this.player != null) {
+        PlayerView.switchTargetView(this.player, this.playerView, playerView);
+      }
+    }
+
+    this.playerView = playerView;
+  }
+
+  @Override public final PlayerView getPlayerView() {
+    return this.playerView;
+  }
+
+  @CallSuper @Override public void play() {
+    ensureMediaSource();
+    ensurePlayerView();
+    checkNotNull(player, "Playable#play(): Player is null!");
+    player.setPlayWhenReady(true);
+  }
+
+  @CallSuper @Override public void pause() {
+    // Player is not required to be non-null here.
+    if (player != null) player.setPlayWhenReady(false);
+  }
+
+  @CallSuper @Override public void reset() {
+    this.playbackInfo.reset();
+    if (player != null) {
+      // reset volume to default
+      ToroExo.setVolumeInfo(this.player, new VolumeInfo(false, 1.f));
+      player.stop(true);
+    }
+    this.mediaSource = null; // so it will be re-prepared when play() is called.
+    this.sourcePrepared = false;
+  }
+
+  @CallSuper @Override public void release() {
+    this.setPlayerView(null);
+    if (this.player != null) {
+      // reset volume to default
+      ToroExo.setVolumeInfo(this.player, new VolumeInfo(false, 1.f));
+      this.player.stop(true);
+      if (listenerApplied) {
+        player.removeListener(listeners);
+        player.removeVideoListener(listeners);
+        player.removeTextOutput(listeners);
+        player.removeMetadataOutput(listeners);
+        if (this.player instanceof ToroExoPlayer) {
+          ((ToroExoPlayer) this.player).removeOnVolumeChangeListener(this.volumeChangeListeners);
+        }
+        listenerApplied = false;
+      }
+      with(checkNotNull(creator.getContext(), "ExoCreator has no Context")) //
+          .releasePlayer(this.creator, this.player);
+    }
+    this.player = null;
+    this.mediaSource = null;
+    this.sourcePrepared = false;
+  }
+
+  @CallSuper @NonNull @Override public PlaybackInfo getPlaybackInfo() {
+    updatePlaybackInfo();
+    return new PlaybackInfo(playbackInfo.getResumeWindow(), playbackInfo.getResumePosition(),
+        playbackInfo.getVolumeInfo());
+  }
+
+  @CallSuper @Override public void setPlaybackInfo(@NonNull PlaybackInfo playbackInfo) {
+    this.playbackInfo.setResumeWindow(playbackInfo.getResumeWindow());
+    this.playbackInfo.setResumePosition(playbackInfo.getResumePosition());
+    this.setVolumeInfo(playbackInfo.getVolumeInfo());
+
+    if (player != null) {
+      ToroExo.setVolumeInfo(player, this.playbackInfo.getVolumeInfo());
+      boolean haveResumePosition = this.playbackInfo.getResumeWindow() != INDEX_UNSET;
+      if (haveResumePosition) {
+        player.seekTo(this.playbackInfo.getResumeWindow(), this.playbackInfo.getResumePosition());
+      }
+    }
+  }
+
+  @Override public final void addEventListener(@NonNull EventListener listener) {
+    //noinspection ConstantConditions
+    if (listener != null) this.listeners.add(listener);
+  }
+
+  @Override public final void removeEventListener(EventListener listener) {
+    this.listeners.remove(listener);
+  }
+
+  @CallSuper @Override public void setVolume(float volume) {
+    checkNotNull(player, "Playable#setVolume(): Player is null!");
+    playbackInfo.getVolumeInfo().setTo(volume == 0, volume);
+    ToroExo.setVolumeInfo(player, this.playbackInfo.getVolumeInfo());
+  }
+
+  @CallSuper @Override public float getVolume() {
+    return checkNotNull(player, "Playable#getVolume(): Player is null!").getVolume();
+  }
+
+  @Override public boolean setVolumeInfo(@NonNull VolumeInfo volumeInfo) {
+    boolean changed = !this.playbackInfo.getVolumeInfo().equals(checkNotNull(volumeInfo));
+    if (changed) {
+      this.playbackInfo.getVolumeInfo().setTo(volumeInfo.isMute(), volumeInfo.getVolume());
+      if (player != null) ToroExo.setVolumeInfo(player, this.playbackInfo.getVolumeInfo());
+    }
+    return changed;
+  }
+
+  @NonNull @Override public VolumeInfo getVolumeInfo() {
+    return this.playbackInfo.getVolumeInfo();
+  }
+
+  @Override public void setParameters(@Nullable PlaybackParameters parameters) {
+    checkNotNull(player, "Playable#setParameters(PlaybackParameters): Player is null") //
+        .setPlaybackParameters(parameters);
+  }
+
+  @Override public PlaybackParameters getParameters() {
+    return checkNotNull(player, "Playable#getParameters(): Player is null").getPlaybackParameters();
+  }
+
+  @Override
+  public void addOnVolumeChangeListener(@NonNull ToroPlayer.OnVolumeChangeListener listener) {
+    volumeChangeListeners.add(checkNotNull(listener));
+  }
+
+  @Override
+  public void removeOnVolumeChangeListener(@Nullable ToroPlayer.OnVolumeChangeListener listener) {
+    volumeChangeListeners.remove(listener);
+  }
+
+  @Override public boolean isPlaying() {
+    return player != null && player.getPlayWhenReady();
+  }
+
+  @Override public void addErrorListener(@NonNull ToroPlayer.OnErrorListener listener) {
+    this.errorListeners.add(checkNotNull(listener));
+  }
+
+  @Override public void removeErrorListener(@Nullable ToroPlayer.OnErrorListener listener) {
+    this.errorListeners.remove(listener);
+  }
+
+  final void updatePlaybackInfo() {
+    if (player == null || player.getPlaybackState() == Player.STATE_IDLE) return;
+    playbackInfo.setResumeWindow(player.getCurrentWindowIndex());
+    playbackInfo.setResumePosition(player.isCurrentWindowSeekable() ? //
+        Math.max(0, player.getCurrentPosition()) : TIME_UNSET);
+    playbackInfo.setVolumeInfo(ToroExo.getVolumeInfo(player));
+  }
+
+  private void ensurePlayerView() {
+    if (playerView != null && playerView.getPlayer() != player) playerView.setPlayer(player);
+  }
+
+  // TODO [20180822] Double check this.
+  private void ensureMediaSource() {
+    if (mediaSource == null) {  // Only actually prepare the source when play() is called.
+      sourcePrepared = false;
+      mediaSource = creator.createMediaSource(mediaUri, fileExt);
+    }
+
+    if (!sourcePrepared) {
+      ensurePlayer(); // sourcePrepared is set to false only when player is null.
+      beforePrepareMediaSource();
+      player.prepare(mediaSource, playbackInfo.getResumeWindow() == C.INDEX_UNSET, false);
+      sourcePrepared = true;
+    }
+  }
+
+  private void ensurePlayer() {
+    if (player == null) {
+      sourcePrepared = false;
+      player = with(checkNotNull(creator.getContext(), "ExoCreator has no Context")) //
+          .requestPlayer(creator);
+      listenerApplied = false;
+    }
+
+    if (!listenerApplied) {
+      if (player instanceof ToroExoPlayer) {
+        ((ToroExoPlayer) player).addOnVolumeChangeListener(volumeChangeListeners);
+      }
+      player.addListener(listeners);
+      player.addVideoListener(listeners);
+      player.addTextOutput(listeners);
+      player.addMetadataOutput(listeners);
+      listenerApplied = true;
+    }
+
+    ToroExo.setVolumeInfo(player, this.playbackInfo.getVolumeInfo());
+    boolean haveResumePosition = playbackInfo.getResumeWindow() != C.INDEX_UNSET;
+    if (haveResumePosition) {
+      player.seekTo(playbackInfo.getResumeWindow(), playbackInfo.getResumePosition());
+    }
+  }
+
+  // Trick to inject to the Player creation event.
+  // Required for AdsLoader to set Player.
+  protected void beforePrepareMediaSource() {
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayerDispatcher.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayerDispatcher.java
new file mode 100644
index 00000000..4f86ccd9
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayerDispatcher.java
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+/**
+ * This is an addition layer used in PlayerManager. Setting this where
+ * {@link #getDelayToPlay(ToroPlayer)} returns a positive value will result in a delay in playback
+ * play(). While returning {@link #DELAY_NONE} will dispatch the action immediately, and returning
+ * {@link #DELAY_INFINITE} will not dispatch the action.
+ *
+ * @author eneim (2018/02/24).
+ * @since 3.4.0
+ */
+
+public interface PlayerDispatcher {
+
+  int DELAY_INFINITE = -1;
+
+  int DELAY_NONE = 0;
+
+  /**
+   * Return the number of milliseconds that a call to {@link ToroPlayer#play()} should be delayed.
+   * Returning {@link #DELAY_INFINITE} will not start the playback, while returning {@link
+   * #DELAY_NONE} will start it immediately.
+   *
+   * @param player the player that is about to play.
+   * @return number of milliseconds to delay the play, or one of {@link #DELAY_INFINITE} or
+   * {@link #DELAY_NONE}. No other negative number should be used.
+   */
+  int getDelayToPlay(ToroPlayer player);
+
+  PlayerDispatcher DEFAULT = new PlayerDispatcher() {
+    @Override public int getDelayToPlay(ToroPlayer player) {
+      return DELAY_NONE;
+    }
+  };
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayerSelector.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayerSelector.java
new file mode 100644
index 00000000..e42a55a7
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/PlayerSelector.java
@@ -0,0 +1,151 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static java.util.Collections.emptyList;
+import static java.util.Collections.singletonList;
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.visibleAreaOffset;
+import static ml.docilealligator.infinityforreddit.videoautoplay.annotations.Sorted.Order.ASCENDING;
+
+import androidx.annotation.NonNull;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import java.util.NavigableMap;
+import java.util.TreeMap;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.Sorted;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
+
+/**
+ * @author eneim | 6/2/17.
+ *
+ * PlayerSelector is a convenient class to help selecting the players to start Media
+ * playback.
+ *
+ * On specific event of RecyclerView, such as Child view attached/detached, scroll, the
+ * Collection of players those are available for a playback will change. PlayerSelector is
+ * responded to select a specific number of players from that updated Collection to start a
+ * new playback or pause an old playback if the corresponding Player is not selected
+ * anymore.
+ *
+ * Client should implement a custom PlayerSelecter and set it to the Container for expected
+ * behaviour. By default, Toro comes with linear selection implementation (the Selector
+ * that will iterate over the Collection and select the players from top to bottom until a
+ * certain condition is fullfilled, for example the maximum of player count is reached).
+ *
+ * Custom Selector can have more complicated selecting logics, for example: among 2n + 1
+ * playable widgets, select n players in the middles ...
+ */
+
+@SuppressWarnings("unused") //
+public interface PlayerSelector {
+
+  String TAG = "ToroLib:Selector";
+
+  /**
+   * Select a collection of {@link ToroPlayer}s to start a playback (if there is non-playing) item.
+   * Playing item are also selected.
+   *
+   * @param container current {@link Container} that holds the players.
+   * @param items a mutable collection of candidate {@link ToroPlayer}s, which are the players
+   * those can start a playback. Items are sorted in order obtained from
+   * {@link ToroPlayer#getPlayerOrder()}.
+   * @return the collection of {@link ToroPlayer}s to start a playback. An on-going playback can be
+   * selected, but it will keep playing.
+   */
+  @NonNull Collection<ToroPlayer> select(@NonNull Container container,
+                                                     @Sorted(order = ASCENDING) @NonNull List<ToroPlayer> items);
+
+  /**
+   * The 'reverse' selector of this selector, which can help to select the reversed collection of
+   * that expected by this selector.
+   * For example: this selector will select the first playable {@link ToroPlayer} from top, so the
+   * 'reverse' selector will select the last playable {@link ToroPlayer} from top.
+   *
+   * @return The PlayerSelector that has opposite selecting logic. If there is no special one,
+   * return "this".
+   */
+  @NonNull PlayerSelector reverse();
+
+  PlayerSelector DEFAULT = new PlayerSelector() {
+    @NonNull @Override public Collection<ToroPlayer> select(@NonNull Container container, //
+                                                                        @Sorted(order = ASCENDING) @NonNull List<ToroPlayer> items) {
+      int count = items.size();
+      return count > 0 ? singletonList(items.get(0)) : Collections.<ToroPlayer>emptyList();
+    }
+
+    @NonNull @Override public PlayerSelector reverse() {
+      return DEFAULT_REVERSE;
+    }
+  };
+
+  PlayerSelector DEFAULT_REVERSE = new PlayerSelector() {
+    @NonNull @Override public Collection<ToroPlayer> select(@NonNull Container container, //
+                                                                        @Sorted(order = ASCENDING) @NonNull List<ToroPlayer> items) {
+      int count = items.size();
+      return count > 0 ? singletonList(items.get(count - 1)) : Collections.<ToroPlayer>emptyList();
+    }
+
+    @NonNull @Override public PlayerSelector reverse() {
+      return DEFAULT;
+    }
+  };
+
+  @SuppressWarnings("unused") PlayerSelector BY_AREA = new PlayerSelector() {
+
+    NavigableMap<Float, ToroPlayer> areas = new TreeMap<>(new Comparator<Float>() {
+      @Override public int compare(Float o1, Float o2) {
+        return Float.compare(o2, o1); // reverse order, from high to low.
+      }
+    });
+
+    @NonNull @Override public Collection<ToroPlayer> select(@NonNull final Container container,
+                                                            @Sorted(order = ASCENDING) @NonNull List<ToroPlayer> items) {
+      areas.clear();
+      int count = items.size();
+      if (count > 0) {
+        for (int i = 0; i < count; i++) {
+          ToroPlayer item = items.get(i);
+          if (!areas.containsValue(item)) areas.put(visibleAreaOffset(item, container), item);
+        }
+
+        count = areas.size();
+      }
+
+      return count > 0 ? singletonList(areas.firstEntry().getValue())
+          : Collections.<ToroPlayer>emptyList();
+    }
+
+    @NonNull @Override public PlayerSelector reverse() {
+      return this;
+    }
+  };
+
+  @SuppressWarnings("unused") PlayerSelector NONE = new PlayerSelector() {
+    @NonNull @Override public Collection<ToroPlayer> select(@NonNull Container container, //
+                                                                        @Sorted(order = ASCENDING) @NonNull List<ToroPlayer> items) {
+      return emptyList();
+    }
+
+    @NonNull @Override public PlayerSelector reverse() {
+      return this;
+    }
+  };
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroExo.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroExo.java
new file mode 100644
index 00000000..147157b6
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroExo.java
@@ -0,0 +1,297 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static android.widget.Toast.LENGTH_SHORT;
+import static com.google.android.exoplayer2.drm.UnsupportedDrmException.REASON_UNSUPPORTED_SCHEME;
+import static com.google.android.exoplayer2.util.Util.getDrmUuid;
+import static java.lang.Runtime.getRuntime;
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.checkNotNull;
+
+import android.annotation.SuppressLint;
+import android.app.Application;
+import android.content.Context;
+import android.text.TextUtils;
+import android.widget.Toast;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.annotation.RequiresApi;
+import androidx.annotation.RestrictTo;
+import androidx.annotation.StringRes;
+import androidx.core.util.Pools;
+
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.drm.DefaultDrmSessionManager;
+import com.google.android.exoplayer2.drm.DrmSessionManager;
+import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
+import com.google.android.exoplayer2.drm.FrameworkMediaDrm;
+import com.google.android.exoplayer2.drm.HttpMediaDrmCallback;
+import com.google.android.exoplayer2.drm.UnsupportedDrmException;
+import com.google.android.exoplayer2.upstream.DefaultHttpDataSourceFactory;
+import com.google.android.exoplayer2.upstream.HttpDataSource;
+import com.google.android.exoplayer2.util.Util;
+
+import java.net.CookieHandler;
+import java.net.CookieManager;
+import java.net.CookiePolicy;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.UUID;
+
+import ml.docilealligator.infinityforreddit.R;
+import ml.docilealligator.infinityforreddit.utils.APIUtils;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.DrmMedia;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
+
+/**
+ * Global helper class to manage {@link ExoCreator} and {@link SimpleExoPlayer} instances.
+ * In this setup, {@link ExoCreator} and SimpleExoPlayer pools are cached. A {@link Config}
+ * is a key for each {@link ExoCreator}.
+ *
+ * A suggested usage is as below:
+ * <pre><code>
+ * ExoCreator creator = ToroExo.with(this).getDefaultCreator();
+ * Playable playable = creator.createPlayable(uri);
+ * playable.prepare();
+ * // next: setup PlayerView and start the playback.
+ * </code></pre>
+ *
+ * @author eneim (2018/01/26).
+ * @since 3.4.0
+ */
+
+public final class ToroExo {
+
+  private static final String TAG = "ToroExo";
+
+  // Magic number: Build.VERSION.SDK_INT / 6 --> API 16 ~ 18 will set pool size to 2, etc.
+  @SuppressWarnings("WeakerAccess") //
+  static final int MAX_POOL_SIZE = Math.max(Util.SDK_INT / 6, getRuntime().availableProcessors());
+  @SuppressLint("StaticFieldLeak")  //
+  static volatile ToroExo toro;
+
+  public static ToroExo with(Context context) {
+    if (toro == null) {
+      synchronized (ToroExo.class) {
+        if (toro == null) toro = new ToroExo(context.getApplicationContext());
+      }
+    }
+    return toro;
+  }
+
+  @NonNull final String appName;
+  @NonNull final Context context;  // Application context
+  @NonNull private final Map<Config, ExoCreator> creators;
+  @NonNull private final Map<ExoCreator, Pools.Pool<SimpleExoPlayer>> playerPools;
+
+  private Config defaultConfig; // will be created on the first time it is used.
+
+  private ToroExo(@NonNull Context context /* Application context */) {
+    this.context = context;
+    this.appName = getUserAgent();
+    this.playerPools = new HashMap<>();
+    this.creators = new HashMap<>();
+
+    // Adapt from ExoPlayer demo app. Start this on demand.
+    CookieManager cookieManager = new CookieManager();
+    cookieManager.setCookiePolicy(CookiePolicy.ACCEPT_ORIGINAL_SERVER);
+    if (CookieHandler.getDefault() != cookieManager) {
+      CookieHandler.setDefault(cookieManager);
+    }
+  }
+
+  /**
+   * Utility method to produce {@link ExoCreator} instance from a {@link Config}.
+   */
+  public final ExoCreator getCreator(Config config) {
+    ExoCreator creator = this.creators.get(config);
+    if (creator == null) {
+      creator = new DefaultExoCreator(this, config);
+      this.creators.put(config, creator);
+    }
+
+    return creator;
+  }
+
+  @SuppressWarnings("WeakerAccess") public final Config getDefaultConfig() {
+    if (defaultConfig == null) defaultConfig = new Config.Builder(context).build();
+    return defaultConfig;
+  }
+
+  /**
+   * Get the default {@link ExoCreator}. This ExoCreator is configured by {@link #defaultConfig}.
+   */
+  public final ExoCreator getDefaultCreator() {
+    return getCreator(getDefaultConfig());
+  }
+
+  /**
+   * Request an instance of {@link SimpleExoPlayer}. It can be an existing instance cached by Pool
+   * or new one.
+   *
+   * The creator may or may not be the one created by either {@link #getCreator(Config)} or
+   * {@link #getDefaultCreator()}.
+   *
+   * @param creator the {@link ExoCreator} that is scoped to the {@link SimpleExoPlayer} config.
+   * @return an usable {@link SimpleExoPlayer} instance.
+   */
+  @NonNull  //
+  public final SimpleExoPlayer requestPlayer(@NonNull ExoCreator creator) {
+    SimpleExoPlayer player = getPool(checkNotNull(creator)).acquire();
+    if (player == null) player = creator.createPlayer();
+    return player;
+  }
+
+  /**
+   * Release player to Pool attached to the creator.
+   *
+   * @param creator the {@link ExoCreator} that created the player.
+   * @param player the {@link SimpleExoPlayer} to be released back to the Pool
+   * @return true if player is released to relevant Pool, false otherwise.
+   */
+  @SuppressWarnings({ "WeakerAccess", "UnusedReturnValue" }) //
+  public final boolean releasePlayer(@NonNull ExoCreator creator, @NonNull SimpleExoPlayer player) {
+    return getPool(checkNotNull(creator)).release(player);
+  }
+
+  /**
+   * Release and clear all current cached ExoPlayer instances. This should be called when
+   * client Application runs out of memory ({@link Application#onTrimMemory(int)} for example).
+   */
+  public final void cleanUp() {
+    // TODO [2018/03/07] Test this. Ref: https://stackoverflow.com/a/1884916/1553254
+    for (Iterator<Map.Entry<ExoCreator, Pools.Pool<SimpleExoPlayer>>> it =
+        playerPools.entrySet().iterator(); it.hasNext(); ) {
+      Pools.Pool<SimpleExoPlayer> pool = it.next().getValue();
+      SimpleExoPlayer item;
+      while ((item = pool.acquire()) != null) item.release();
+      it.remove();
+    }
+  }
+
+  /// internal APIs
+  private Pools.Pool<SimpleExoPlayer> getPool(ExoCreator creator) {
+    Pools.Pool<SimpleExoPlayer> pool = playerPools.get(creator);
+    if (pool == null) {
+      pool = new Pools.SimplePool<>(MAX_POOL_SIZE);
+      playerPools.put(creator, pool);
+    }
+
+    return pool;
+  }
+
+  /**
+   * Get a possibly-non-localized String from existing resourceId.
+   */
+  /* pkg */ String getString(@StringRes int resId, @Nullable Object... params) {
+    return params == null || params.length < 1 ?  //
+        this.context.getString(resId) : this.context.getString(resId, params);
+  }
+
+  /**
+   * Utility method to build a {@link DrmSessionManager} that can be used in {@link Config}
+   *
+   * Usage:
+   * <pre><code>
+   *   DrmSessionManager manager = ToroExo.with(context).createDrmSessionManager(mediaDrm);
+   *   Config config = new Config.Builder().setDrmSessionManager(manager);
+   *   ExoCreator creator = ToroExo.with(context).getCreator(config);
+   * </code></pre>
+   */
+  @SuppressWarnings("unused") @RequiresApi(18) @Nullable //
+  public DrmSessionManager<FrameworkMediaCrypto> createDrmSessionManager(@NonNull DrmMedia drm) {
+    DrmSessionManager<FrameworkMediaCrypto> drmSessionManager = null;
+    int errorStringId = R.string.error_drm_unknown;
+    String subString = null;
+    if (Util.SDK_INT < 18) {
+      errorStringId = R.string.error_drm_not_supported;
+    } else {
+      UUID drmSchemeUuid = getDrmUuid(checkNotNull(drm).getType());
+      if (drmSchemeUuid == null) {
+        errorStringId = R.string.error_drm_unsupported_scheme;
+      } else {
+        HttpDataSource.Factory factory = new DefaultHttpDataSourceFactory(appName);
+        try {
+          drmSessionManager = buildDrmSessionManagerV18(drmSchemeUuid, drm.getLicenseUrl(),
+              drm.getKeyRequestPropertiesArray(), drm.multiSession(), factory);
+        } catch (UnsupportedDrmException e) {
+          e.printStackTrace();
+          errorStringId = e.reason == REASON_UNSUPPORTED_SCHEME ? //
+              R.string.error_drm_unsupported_scheme : R.string.error_drm_unknown;
+          if (e.reason == REASON_UNSUPPORTED_SCHEME) {
+            subString = drm.getType();
+          }
+        }
+      }
+    }
+
+    if (drmSessionManager == null) {
+      String error = TextUtils.isEmpty(subString) ? context.getString(errorStringId)
+          : context.getString(errorStringId) + ": " + subString;
+      Toast.makeText(context, error, LENGTH_SHORT).show();
+    }
+
+    return drmSessionManager;
+  }
+
+  @RequiresApi(18) private static DrmSessionManager<FrameworkMediaCrypto> buildDrmSessionManagerV18(
+      @NonNull UUID uuid, @Nullable String licenseUrl, @Nullable String[] keyRequestPropertiesArray,
+      boolean multiSession, @NonNull HttpDataSource.Factory httpDataSourceFactory)
+      throws UnsupportedDrmException {
+    HttpMediaDrmCallback drmCallback = new HttpMediaDrmCallback(licenseUrl, httpDataSourceFactory);
+    if (keyRequestPropertiesArray != null) {
+      for (int i = 0; i < keyRequestPropertiesArray.length - 1; i += 2) {
+        drmCallback.setKeyRequestProperty(keyRequestPropertiesArray[i],
+            keyRequestPropertiesArray[i + 1]);
+      }
+    }
+    return new DefaultDrmSessionManager<>(uuid, FrameworkMediaDrm.newInstance(uuid), drmCallback,
+        null, multiSession);
+  }
+
+  // Share the code of setting Volume. For use inside library only.
+  @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) //
+  public static void setVolumeInfo(@NonNull SimpleExoPlayer player,
+      @NonNull VolumeInfo volumeInfo) {
+    if (player instanceof ToroExoPlayer) {
+      ((ToroExoPlayer) player).setVolumeInfo(volumeInfo);
+    } else {
+      if (volumeInfo.isMute()) {
+        player.setVolume(0f);
+      } else {
+        player.setVolume(volumeInfo.getVolume());
+      }
+    }
+  }
+
+  @SuppressWarnings("WeakerAccess") @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) //
+  public static VolumeInfo getVolumeInfo(SimpleExoPlayer player) {
+    if (player instanceof ToroExoPlayer) {
+      return new VolumeInfo(((ToroExoPlayer) player).getVolumeInfo());
+    } else {
+      float volume = player.getVolume();
+      return new VolumeInfo(volume == 0, volume);
+    }
+  }
+
+  @SuppressWarnings("SameParameterValue")
+  private static String getUserAgent() {
+    return APIUtils.USER_AGENT;
+  }
+}
\ No newline at end of file
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroExoPlayer.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroExoPlayer.java
new file mode 100644
index 00000000..2fe92569
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroExoPlayer.java
@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.checkNotNull;
+
+import android.content.Context;
+import android.os.Looper;
+
+import androidx.annotation.CallSuper;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.exoplayer2.LoadControl;
+import com.google.android.exoplayer2.RenderersFactory;
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.drm.DrmSessionManager;
+import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
+import com.google.android.exoplayer2.trackselection.TrackSelector;
+import com.google.android.exoplayer2.upstream.BandwidthMeter;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
+
+/**
+ * A custom {@link SimpleExoPlayer} that also notify the change of Volume.
+ *
+ * @author eneim (2018/03/27).
+ */
+@SuppressWarnings("WeakerAccess") //
+public class ToroExoPlayer extends SimpleExoPlayer {
+
+  protected ToroExoPlayer(Context context, RenderersFactory renderersFactory,
+      TrackSelector trackSelector, LoadControl loadControl, BandwidthMeter bandwidthMeter,
+      @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager, Looper looper) {
+    super(context, renderersFactory, trackSelector, loadControl, bandwidthMeter, drmSessionManager,
+        looper);
+  }
+
+  private ToroPlayer.VolumeChangeListeners listeners;
+
+  public final void addOnVolumeChangeListener(@NonNull ToroPlayer.OnVolumeChangeListener listener) {
+    if (this.listeners == null) this.listeners = new ToroPlayer.VolumeChangeListeners();
+    this.listeners.add(checkNotNull(listener));
+  }
+
+  public final void removeOnVolumeChangeListener(ToroPlayer.OnVolumeChangeListener listener) {
+    if (this.listeners != null) this.listeners.remove(listener);
+  }
+
+  public final void clearOnVolumeChangeListener() {
+    if (this.listeners != null) this.listeners.clear();
+  }
+
+  @CallSuper @Override public void setVolume(float audioVolume) {
+    this.setVolumeInfo(new VolumeInfo(audioVolume == 0, audioVolume));
+  }
+
+  private final VolumeInfo volumeInfo = new VolumeInfo(false, 1f);
+
+  @SuppressWarnings("UnusedReturnValue")
+  public final boolean setVolumeInfo(@NonNull VolumeInfo volumeInfo) {
+    boolean changed = !this.volumeInfo.equals(volumeInfo);
+    if (changed) {
+      this.volumeInfo.setTo(volumeInfo.isMute(), volumeInfo.getVolume());
+      super.setVolume(volumeInfo.isMute() ? 0 : volumeInfo.getVolume());
+      if (listeners != null) {
+        for (ToroPlayer.OnVolumeChangeListener listener : this.listeners) {
+          listener.onVolumeChanged(volumeInfo);
+        }
+      }
+    }
+
+    return changed;
+  }
+
+  @SuppressWarnings("unused") @NonNull public final VolumeInfo getVolumeInfo() {
+    return volumeInfo;
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroPlayer.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroPlayer.java
new file mode 100644
index 00000000..5075b1b7
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroPlayer.java
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import android.view.View;
+
+import androidx.annotation.IntDef;
+import androidx.annotation.NonNull;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.concurrent.CopyOnWriteArraySet;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
+
+/**
+ * Definition of a Player used in Toro. Besides common playback command ({@link #play()}, {@link
+ * #pause()}, etc), it provides the library necessary information about the playback and
+ * components.
+ *
+ * @author eneim | 5/31/17.
+ */
+
+public interface ToroPlayer {
+
+  @NonNull View getPlayerView();
+
+  @NonNull
+  PlaybackInfo getCurrentPlaybackInfo();
+
+  /**
+   * Initialize resource for the incoming playback. After this point, {@link ToroPlayer} should be
+   * able to start the playback at anytime in the future (This doesn't mean that any call to {@link
+   * ToroPlayer#play()} will start the playback immediately. It can start buffering enough resource
+   * before any rendering).
+   *
+   * @param container the RecyclerView contains this Player.
+   * @param playbackInfo initialize info for the preparation.
+   */
+  void initialize(@NonNull Container container, @NonNull PlaybackInfo playbackInfo);
+
+  /**
+   * Start playback or resume from a pausing state.
+   */
+  void play();
+
+  /**
+   * Pause current playback.
+   */
+  void pause();
+
+  boolean isPlaying();
+
+  /**
+   * Tear down all the setup. This should release all player instances.
+   */
+  void release();
+
+  boolean wantsToPlay();
+
+  /**
+   * @return prefer playback order in list. Can be customized.
+   */
+  int getPlayerOrder();
+
+  /**
+   * A convenient callback to help {@link ToroPlayer} to listen to different playback states.
+   */
+  interface EventListener {
+
+    void onFirstFrameRendered();
+
+    void onBuffering(); // ExoPlayer state: 2
+
+    void onPlaying(); // ExoPlayer state: 3, play flag: true
+
+    void onPaused();  // ExoPlayer state: 3, play flag: false
+
+    void onCompleted(); // ExoPlayer state: 4
+  }
+
+  interface OnVolumeChangeListener {
+
+    void onVolumeChanged(@NonNull VolumeInfo volumeInfo);
+  }
+
+  interface OnErrorListener {
+
+    void onError(Exception error);
+  }
+
+  class EventListeners extends CopyOnWriteArraySet<EventListener> implements EventListener {
+
+    @Override public void onFirstFrameRendered() {
+      for (EventListener listener : this) {
+        listener.onFirstFrameRendered();
+      }
+    }
+
+    @Override public void onBuffering() {
+      for (EventListener listener : this) {
+        listener.onBuffering();
+      }
+    }
+
+    @Override public void onPlaying() {
+      for (EventListener listener : this) {
+        listener.onPlaying();
+      }
+    }
+
+    @Override public void onPaused() {
+      for (EventListener listener : this) {
+        listener.onPaused();
+      }
+    }
+
+    @Override public void onCompleted() {
+      for (EventListener listener : this) {
+        listener.onCompleted();
+      }
+    }
+  }
+
+  class ErrorListeners extends CopyOnWriteArraySet<OnErrorListener>
+      implements ToroPlayer.OnErrorListener {
+
+    @Override public void onError(Exception error) {
+      for (ToroPlayer.OnErrorListener listener : this) {
+        listener.onError(error);
+      }
+    }
+  }
+
+  class VolumeChangeListeners extends CopyOnWriteArraySet<ToroPlayer.OnVolumeChangeListener>
+      implements ToroPlayer.OnVolumeChangeListener {
+
+    @Override public void onVolumeChanged(@NonNull VolumeInfo volumeInfo) {
+      for (ToroPlayer.OnVolumeChangeListener listener : this) {
+        listener.onVolumeChanged(volumeInfo);
+      }
+    }
+  }
+
+  // Adapt from ExoPlayer.
+  @Retention(RetentionPolicy.SOURCE)  //
+  @IntDef({ State.STATE_IDLE, State.STATE_BUFFERING, State.STATE_READY, State.STATE_END })  //
+  @interface State {
+    int STATE_IDLE = 1;
+    int STATE_BUFFERING = 2;
+    int STATE_READY = 3;
+    int STATE_END = 4;
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroUtil.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroUtil.java
new file mode 100644
index 00000000..ecfc7d1d
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ToroUtil.java
@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay;
+
+import android.graphics.Point;
+import android.graphics.Rect;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.ViewParent;
+
+import androidx.annotation.FloatRange;
+import androidx.annotation.NonNull;
+import androidx.coordinatorlayout.widget.CoordinatorLayout;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
+
+/**
+ * @author eneim | 5/31/17.
+ */
+
+public final class ToroUtil {
+
+  @SuppressWarnings("unused") private static final String TAG = "ToroLib:Util";
+
+  private ToroUtil() {
+    throw new RuntimeException("Meh!");
+  }
+
+  /**
+   * Get the ratio in range of 0.0 ~ 1.0 the visible area of a {@link ToroPlayer}'s playerView.
+   *
+   * @param player the {@link ToroPlayer} need to investigate.
+   * @param container the {@link ViewParent} that holds the {@link ToroPlayer}. If {@code null}
+   * then this method must returns 0.0f;
+   * @return the value in range of 0.0 ~ 1.0 of the visible area.
+   */
+  @FloatRange(from = 0.0, to = 1.0) //
+  public static float visibleAreaOffset(@NonNull ToroPlayer player, ViewParent container) {
+    if (container == null) return 0.0f;
+
+    View playerView = player.getPlayerView();
+    Rect drawRect = new Rect();
+    playerView.getDrawingRect(drawRect);
+    int drawArea = drawRect.width() * drawRect.height();
+
+    Rect playerRect = new Rect();
+    boolean visible = playerView.getGlobalVisibleRect(playerRect, new Point());
+
+    float offset = 0.f;
+    if (visible && drawArea > 0) {
+      int visibleArea = playerRect.height() * playerRect.width();
+      offset = visibleArea / (float) drawArea;
+    }
+    return offset;
+  }
+
+  /**
+   * Ensures that an object reference passed as a parameter to the calling
+   * method is not null.
+   *
+   * @param reference an object reference
+   * @return the non-null reference that was validated
+   * @throws NullPointerException if {@code reference} is null
+   */
+  public static @NonNull <T> T checkNotNull(final T reference) {
+    if (reference == null) {
+      throw new NullPointerException();
+    }
+    return reference;
+  }
+
+  /**
+   * Ensures that an object reference passed as a parameter to the calling
+   * method is not null.
+   *
+   * @param reference an object reference
+   * @param errorMessage the exception message to use if the check fails; will
+   * be converted to a string using {@link String#valueOf(Object)}
+   * @return the non-null reference that was validated
+   * @throws NullPointerException if {@code reference} is null
+   */
+  public static @NonNull <T> T checkNotNull(final T reference, final Object errorMessage) {
+    if (reference == null) {
+      throw new NullPointerException(String.valueOf(errorMessage));
+    }
+    return reference;
+  }
+
+  @SuppressWarnings("unchecked")  //
+  public static void wrapParamBehavior(@NonNull final Container container,
+      final Container.BehaviorCallback callback) {
+    container.setBehaviorCallback(callback);
+    ViewGroup.LayoutParams params = container.getLayoutParams();
+    if (params instanceof CoordinatorLayout.LayoutParams) {
+      CoordinatorLayout.Behavior temp = ((CoordinatorLayout.LayoutParams) params).getBehavior();
+      if (temp != null) {
+        ((CoordinatorLayout.LayoutParams) params).setBehavior(new Container.Behavior(temp));
+      }
+    }
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/Beta.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/Beta.java
new file mode 100644
index 00000000..11f9944b
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/Beta.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.annotations;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * Indicate that the feature is still in Beta testing and may not ready for production.
+ *
+ * @author eneim (2018/02/27).
+ */
+
+@Retention(RetentionPolicy.SOURCE)  //
+public @interface Beta {
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/RemoveIn.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/RemoveIn.java
new file mode 100644
index 00000000..504c0ebf
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/RemoveIn.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.annotations;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * This annotation is to mark deprecated objects to be removed from library from a certain version,
+ * specific by {@link #version()}. This is to help quickly navigate through them, and to make it clear.
+ *
+ * @author eneim (2018/05/01).
+ */
+@Retention(RetentionPolicy.SOURCE)  //
+public @interface RemoveIn {
+
+  String version();
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/Sorted.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/Sorted.java
new file mode 100644
index 00000000..91b72c85
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/annotations/Sorted.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.annotations;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * @author eneim (2018/02/07).
+ *
+ *         Annotate that a list of items are sorted in specific {@link Order}.
+ */
+
+@Retention(RetentionPolicy.SOURCE)  //
+public @interface Sorted {
+
+  Order order() default Order.ASCENDING;
+
+  enum Order {
+    ASCENDING, DESCENDING, UNSORTED
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/helper/ToroPlayerHelper.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/helper/ToroPlayerHelper.java
new file mode 100644
index 00000000..7f2aa825
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/helper/ToroPlayerHelper.java
@@ -0,0 +1,241 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.helper;
+
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.checkNotNull;
+
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Message;
+
+import androidx.annotation.CallSuper;
+import androidx.annotation.FloatRange;
+import androidx.annotation.NonNull;
+import androidx.annotation.RestrictTo;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.RemoveIn;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
+import ml.docilealligator.infinityforreddit.videoautoplay.widget.Container;
+
+/**
+ * General definition of a helper class for a specific {@link ToroPlayer}. This class helps
+ * forwarding the playback state to the {@link ToroPlayer} if there is any {@link EventListener}
+ * registered. It also requests the initialization for the Player.
+ *
+ * From 3.4.0, this class can be reused as much as possible.
+ *
+ * @author eneim | 6/11/17.
+ */
+public abstract class ToroPlayerHelper {
+
+  private final Handler handler = new Handler(Looper.getMainLooper(), new Handler.Callback() {
+    @Override public boolean handleMessage(Message msg) {
+      boolean playWhenReady = (boolean) msg.obj;
+      switch (msg.what) {
+        case ToroPlayer.State.STATE_IDLE:
+          // TODO: deal with idle state, maybe error handling.
+          break;
+        case ToroPlayer.State.STATE_BUFFERING /* Player.STATE_BUFFERING */:
+          internalListener.onBuffering();
+          for (ToroPlayer.EventListener listener : getEventListeners()) {
+            listener.onBuffering();
+          }
+          break;
+        case ToroPlayer.State.STATE_READY /*  Player.STATE_READY */:
+          if (playWhenReady) {
+            internalListener.onPlaying();
+          } else {
+            internalListener.onPaused();
+          }
+
+          for (ToroPlayer.EventListener listener : getEventListeners()) {
+            if (playWhenReady) {
+              listener.onPlaying();
+            } else {
+              listener.onPaused();
+            }
+          }
+          break;
+        case ToroPlayer.State.STATE_END /* Player.STATE_ENDED */:
+          internalListener.onCompleted();
+          for (ToroPlayer.EventListener listener : getEventListeners()) {
+            listener.onCompleted();
+          }
+          break;
+        default:
+          break;
+      }
+      return true;
+    }
+  });
+
+  @NonNull protected final ToroPlayer player;
+
+  // This instance should be setup from #initialize and cleared from #release
+  protected Container container;
+
+  @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) //
+  private ToroPlayer.EventListeners eventListeners;
+
+  @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) //
+  private ToroPlayer.VolumeChangeListeners volumeChangeListeners;
+
+  @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) //
+  private ToroPlayer.ErrorListeners errorListeners;
+
+  @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) //
+  protected final ToroPlayer.EventListener internalListener = new ToroPlayer.EventListener() {
+    @Override public void onFirstFrameRendered() {
+
+    }
+
+    @Override public void onBuffering() {
+      // do nothing
+    }
+
+    @Override public void onPlaying() {
+      player.getPlayerView().setKeepScreenOn(true);
+    }
+
+    @Override public void onPaused() {
+      player.getPlayerView().setKeepScreenOn(false);
+      if (container != null) {
+        container.savePlaybackInfo( //
+            player.getPlayerOrder(), checkNotNull(player.getCurrentPlaybackInfo()));
+      }
+    }
+
+    @Override public void onCompleted() {
+      if (container != null) {
+        // Save PlaybackInfo.SCRAP to mark this player to be re-init.
+        container.savePlaybackInfo(player.getPlayerOrder(), PlaybackInfo.SCRAP);
+      }
+    }
+  };
+
+  public ToroPlayerHelper(@NonNull ToroPlayer player) {
+    this.player = player;
+  }
+
+  public final void addPlayerEventListener(@NonNull ToroPlayer.EventListener listener) {
+    getEventListeners().add(checkNotNull(listener));
+  }
+
+  public final void removePlayerEventListener(ToroPlayer.EventListener listener) {
+    if (eventListeners != null) eventListeners.remove(listener);
+  }
+
+  /**
+   * Initialize the necessary resource for the incoming playback. For example, prepare the
+   * ExoPlayer instance for SimpleExoPlayerView. The initialization is feed by an initial playback
+   * info, telling if the playback should start from a specific position or from beginning.
+   *
+   * Normally this info can be obtained from cache if there is cache manager, or {@link PlaybackInfo#SCRAP}
+   * if there is no such cached information.
+   *
+   * @param playbackInfo the initial playback info.
+   */
+  protected abstract void initialize(@NonNull PlaybackInfo playbackInfo);
+
+  public final void initialize(@NonNull Container container, @NonNull PlaybackInfo playbackInfo) {
+    this.container = container;
+    this.initialize(playbackInfo);
+  }
+
+  public abstract void play();
+
+  public abstract void pause();
+
+  public abstract boolean isPlaying();
+
+  /**
+   * @deprecated use {@link #setVolumeInfo(VolumeInfo)} instead.
+   */
+  @RemoveIn(version = "3.6.0") @Deprecated  //
+  public abstract void setVolume(@FloatRange(from = 0.0, to = 1.0) float volume);
+
+  /**
+   * @deprecated use {@link #getVolumeInfo()} instead.
+   */
+  @RemoveIn(version = "3.6.0") @Deprecated  //
+  public abstract @FloatRange(from = 0.0, to = 1.0) float getVolume();
+
+  public abstract void setVolumeInfo(@NonNull VolumeInfo volumeInfo);
+
+  @NonNull public abstract VolumeInfo getVolumeInfo();
+
+  /**
+   * Get latest playback info. Either on-going playback info if current player is playing, or latest
+   * playback info available if player is paused.
+   *
+   * @return latest {@link PlaybackInfo} of current Player.
+   */
+  @NonNull public abstract PlaybackInfo getLatestPlaybackInfo();
+
+  public abstract void setPlaybackInfo(@NonNull PlaybackInfo playbackInfo);
+
+  @CallSuper
+  public void addOnVolumeChangeListener(@NonNull ToroPlayer.OnVolumeChangeListener listener) {
+    getVolumeChangeListeners().add(checkNotNull(listener));
+  }
+
+  @CallSuper public void removeOnVolumeChangeListener(ToroPlayer.OnVolumeChangeListener listener) {
+    if (volumeChangeListeners != null) volumeChangeListeners.remove(listener);
+  }
+
+  @CallSuper public void addErrorListener(@NonNull ToroPlayer.OnErrorListener listener) {
+    getErrorListeners().add(checkNotNull(listener));
+  }
+
+  @CallSuper public void removeErrorListener(ToroPlayer.OnErrorListener listener) {
+    if (errorListeners != null) errorListeners.remove(listener);
+  }
+
+  @NonNull protected final ToroPlayer.EventListeners getEventListeners() {
+    if (eventListeners == null) eventListeners = new ToroPlayer.EventListeners();
+    return eventListeners;
+  }
+
+  @NonNull protected final ToroPlayer.VolumeChangeListeners getVolumeChangeListeners() {
+    if (volumeChangeListeners == null) {
+      volumeChangeListeners = new ToroPlayer.VolumeChangeListeners();
+    }
+    return volumeChangeListeners;
+  }
+
+  @NonNull protected final ToroPlayer.ErrorListeners getErrorListeners() {
+    if (errorListeners == null) errorListeners = new ToroPlayer.ErrorListeners();
+    return errorListeners;
+  }
+
+  // Mimic ExoPlayer
+  @CallSuper protected final void onPlayerStateUpdated(boolean playWhenReady,
+      @ToroPlayer.State int playbackState) {
+    handler.obtainMessage(playbackState, playWhenReady).sendToTarget();
+  }
+
+  @CallSuper public void release() {
+    handler.removeCallbacksAndMessages(null);
+    this.container = null;
+  }
+
+  @NonNull @Override public String toString() {
+    return "ToroLib:Helper{" + "player=" + player + ", container=" + container + '}';
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/DrmMedia.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/DrmMedia.java
new file mode 100644
index 00000000..f48f3885
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/DrmMedia.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.media;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+/**
+ * @author eneim | 6/5/17.
+ *
+ * A definition of DRM media type.
+ */
+
+public interface DrmMedia {
+
+  // DRM Scheme
+  @NonNull String getType();
+
+  @Nullable String getLicenseUrl();
+
+  @Nullable String[] getKeyRequestPropertiesArray();
+
+  boolean multiSession();
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/PlaybackInfo.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/PlaybackInfo.java
new file mode 100644
index 00000000..445fe80a
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/PlaybackInfo.java
@@ -0,0 +1,144 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.media;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import androidx.annotation.NonNull;
+
+/**
+ * @author eneim | 6/6/17.
+ */
+
+public class PlaybackInfo implements Parcelable {
+
+  public static final long TIME_UNSET = Long.MIN_VALUE + 1;
+
+  public static final int INDEX_UNSET = -1;
+
+  private int resumeWindow;
+  private long resumePosition;
+  @NonNull private VolumeInfo volumeInfo;
+
+  public PlaybackInfo(int resumeWindow, long resumePosition) {
+    this.resumeWindow = resumeWindow;
+    this.resumePosition = resumePosition;
+    this.volumeInfo = new VolumeInfo(false, 1.f);
+  }
+
+  public PlaybackInfo(int resumeWindow, long resumePosition, @NonNull VolumeInfo volumeInfo) {
+    this.resumeWindow = resumeWindow;
+    this.resumePosition = resumePosition;
+    this.volumeInfo = volumeInfo;
+  }
+
+  public PlaybackInfo() {
+    this(INDEX_UNSET, TIME_UNSET);
+  }
+
+  public PlaybackInfo(PlaybackInfo other) {
+    this(other.getResumeWindow(), other.getResumePosition(), other.getVolumeInfo());
+  }
+
+  public int getResumeWindow() {
+    return resumeWindow;
+  }
+
+  public void setResumeWindow(int resumeWindow) {
+    this.resumeWindow = resumeWindow;
+  }
+
+  public long getResumePosition() {
+    return resumePosition;
+  }
+
+  public void setResumePosition(long resumePosition) {
+    this.resumePosition = resumePosition;
+  }
+
+  @NonNull public VolumeInfo getVolumeInfo() {
+    return volumeInfo;
+  }
+
+  public void setVolumeInfo(@NonNull VolumeInfo volumeInfo) {
+    this.volumeInfo = volumeInfo;
+  }
+
+  public void reset() {
+    resumeWindow = INDEX_UNSET;
+    resumePosition = TIME_UNSET;
+    volumeInfo = new VolumeInfo(false, 1.f);
+  }
+
+  @Override public String toString() {
+    return this == SCRAP ? "Info:SCRAP" : //
+        "Info{"
+            + "window="
+            + resumeWindow
+            + ", position="
+            + resumePosition
+            + ", volume="
+            + volumeInfo
+            + '}';
+  }
+
+  @Override public boolean equals(Object o) {
+    if (this == o) return true;
+    if (!(o instanceof PlaybackInfo)) return false;
+
+    PlaybackInfo that = (PlaybackInfo) o;
+
+    if (resumeWindow != that.resumeWindow) return false;
+    return resumePosition == that.resumePosition;
+  }
+
+  @Override public int hashCode() {
+    int result = resumeWindow;
+    result = 31 * result + (int) (resumePosition ^ (resumePosition >>> 32));
+    return result;
+  }
+
+  @Override public int describeContents() {
+    return 0;
+  }
+
+  @Override public void writeToParcel(Parcel dest, int flags) {
+    dest.writeInt(this.resumeWindow);
+    dest.writeLong(this.resumePosition);
+    dest.writeParcelable(this.volumeInfo, flags);
+  }
+
+  protected PlaybackInfo(Parcel in) {
+    this.resumeWindow = in.readInt();
+    this.resumePosition = in.readLong();
+    this.volumeInfo = in.readParcelable(VolumeInfo.class.getClassLoader());
+  }
+
+  public static final Creator<PlaybackInfo> CREATOR = new Creator<PlaybackInfo>() {
+    @Override public PlaybackInfo createFromParcel(Parcel source) {
+      return new PlaybackInfo(source);
+    }
+
+    @Override public PlaybackInfo[] newArray(int size) {
+      return new PlaybackInfo[size];
+    }
+  };
+
+  // A default PlaybackInfo instance, only use this to mark un-initialized players.
+  public static final PlaybackInfo SCRAP = new PlaybackInfo();
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/VolumeInfo.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/VolumeInfo.java
new file mode 100644
index 00000000..34308820
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/media/VolumeInfo.java
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.media;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+import androidx.annotation.FloatRange;
+
+/**
+ * Information about volume of a playback. There are a few state this class could show:
+ *
+ * - An expected volume value.
+ * - State of mute or not.
+ *
+ * When {@link #mute} is {@code true}, {@link #volume} value will be ignored. But when {@link #mute}
+ * is set to {@code false}, actual volume value will be brought to the playback.
+ *
+ * This volume information doesn't relate to system Volume. Which means that even if client set
+ * this to non-mute volume, the device's volume setup wins the actual behavior.
+ *
+ * @author eneim (2018/03/14).
+ */
+public final class VolumeInfo implements Parcelable {
+
+  // Indicate that the playback is in muted state or not.
+  private boolean mute;
+  // The actual Volume value if 'mute' is false.
+  @FloatRange(from = 0, to = 1) private float volume;
+
+  public VolumeInfo(boolean mute, @FloatRange(from = 0, to = 1) float volume) {
+    this.mute = mute;
+    this.volume = volume;
+  }
+
+  public VolumeInfo(VolumeInfo other) {
+    this(other.isMute(), other.getVolume());
+  }
+
+  public boolean isMute() {
+    return mute;
+  }
+
+  public void setMute(boolean mute) {
+    this.mute = mute;
+  }
+
+  @FloatRange(from = 0, to = 1) public float getVolume() {
+    return volume;
+  }
+
+  public void setVolume(@FloatRange(from = 0, to = 1) float volume) {
+    this.volume = volume;
+  }
+
+  public void setTo(boolean mute, @FloatRange(from = 0, to = 1) float volume) {
+    this.mute = mute;
+    this.volume = volume;
+  }
+
+  @Override public int describeContents() {
+    return 0;
+  }
+
+  @Override public void writeToParcel(Parcel dest, int flags) {
+    dest.writeByte(this.mute ? (byte) 1 : (byte) 0);
+    dest.writeFloat(this.volume);
+  }
+
+  protected VolumeInfo(Parcel in) {
+    this.mute = in.readByte() != 0;
+    this.volume = in.readFloat();
+  }
+
+  public static final Creator<VolumeInfo> CREATOR = new ClassLoaderCreator<VolumeInfo>() {
+    @Override public VolumeInfo createFromParcel(Parcel source, ClassLoader loader) {
+      return new VolumeInfo(source);
+    }
+
+    @Override public VolumeInfo createFromParcel(Parcel source) {
+      return new VolumeInfo(source);
+    }
+
+    @Override public VolumeInfo[] newArray(int size) {
+      return new VolumeInfo[size];
+    }
+  };
+
+  @SuppressWarnings("SimplifiableIfStatement") @Override public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+
+    VolumeInfo that = (VolumeInfo) o;
+
+    if (mute != that.mute) return false;
+    return Float.compare(that.volume, volume) == 0;
+  }
+
+  @Override public int hashCode() {
+    int result = (mute ? 1 : 0);
+    result = 31 * result + (volume != +0.0f ? Float.floatToIntBits(volume) : 0);
+    return result;
+  }
+
+  @Override public String toString() {
+    return "Vol{" + "mute=" + mute + ", volume=" + volume + '}';
+  }
+}
\ No newline at end of file
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ui/ToroControlView.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ui/ToroControlView.java
new file mode 100644
index 00000000..0ab474db
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/ui/ToroControlView.java
@@ -0,0 +1,278 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.ui;
+
+import android.annotation.SuppressLint;
+import android.content.Context;
+import android.util.AttributeSet;
+import android.view.MotionEvent;
+import android.view.View;
+
+import androidx.annotation.NonNull;
+import androidx.core.view.ViewCompat;
+
+import com.google.android.exoplayer2.Player;
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.ui.PlayerControlView;
+import com.google.android.exoplayer2.ui.PlayerView;
+import com.google.android.exoplayer2.ui.TimeBar;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
+import ml.docilealligator.infinityforreddit.R;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroExo;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroExoPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.VolumeInfo;
+
+/**
+ * An extension of {@link PlayerControlView} that adds Volume control buttons. It works on-par
+ * with {@link PlayerView}. Will be automatically inflated when client uses {@link R.layout.toro_exo_player_view}
+ * for {@link PlayerView} layout.
+ *
+ * @author eneim (2018/08/20).
+ * @since 3.6.0.2802
+ */
+public class ToroControlView extends PlayerControlView {
+
+  @SuppressWarnings("unused") static final String TAG = "ToroExo:Control";
+
+  // Statically obtain from super class.
+  protected static Method hideAfterTimeoutMethod; // from parent ...
+  protected static boolean hideMethodFetched;
+  protected static Field hideActionField;
+  protected static boolean hideActionFetched;
+
+  final ComponentListener componentListener;
+  final View volumeUpButton;
+  final View volumeOffButton;
+  final TimeBar volumeBar;
+  final VolumeInfo volumeInfo = new VolumeInfo(false, 1);
+
+  public ToroControlView(Context context) {
+    this(context, null);
+  }
+
+  public ToroControlView(Context context, AttributeSet attrs) {
+    this(context, attrs, 0);
+  }
+
+  public ToroControlView(Context context, AttributeSet attrs, int defStyleAttr) {
+    super(context, attrs, defStyleAttr);
+    volumeOffButton = findViewById(R.id.exo_volume_off);
+    volumeUpButton = findViewById(R.id.exo_volume_up);
+    volumeBar = findViewById(R.id.volume_bar);
+    componentListener = new ComponentListener();
+  }
+
+  @Override public void onAttachedToWindow() {
+    super.onAttachedToWindow();
+    if (volumeUpButton != null) volumeUpButton.setOnClickListener(componentListener);
+    if (volumeOffButton != null) volumeOffButton.setOnClickListener(componentListener);
+    if (volumeBar != null) volumeBar.addListener(componentListener);
+
+    updateVolumeButtons();
+  }
+
+  @Override public void onDetachedFromWindow() {
+    super.onDetachedFromWindow();
+    if (volumeUpButton != null) volumeUpButton.setOnClickListener(null);
+    if (volumeOffButton != null) volumeOffButton.setOnClickListener(null);
+    if (volumeBar != null) volumeBar.removeListener(componentListener);
+    this.setPlayer(null);
+  }
+
+  @SuppressLint("ClickableViewAccessibility") @Override
+  public boolean onTouchEvent(MotionEvent event) {
+    // After processing all children' touch event, this View will just stop it here.
+    // User can click to PlayerView to show/hide this view, but since this View's height is not
+    // significantly large, clicking to show/hide may disturb other actions like clicking to button,
+    // seeking the bars, etc. This extension will stop the touch event here so that PlayerView has
+    // nothing to do when User touch this View.
+    return true;
+  }
+
+  @Override public void setPlayer(Player player) {
+    Player current = super.getPlayer();
+    if (current == player) return;
+
+    if (current instanceof ToroExoPlayer) {
+      ((ToroExoPlayer) current).removeOnVolumeChangeListener(componentListener);
+    }
+
+    super.setPlayer(player);
+    current = super.getPlayer();
+    @NonNull final VolumeInfo tempVol;
+    if (current instanceof ToroExoPlayer) {
+      tempVol = ((ToroExoPlayer) current).getVolumeInfo();
+      ((ToroExoPlayer) current).addOnVolumeChangeListener(componentListener);
+    } else if (current instanceof SimpleExoPlayer) {
+      float volume = ((SimpleExoPlayer) current).getVolume();
+      tempVol = new VolumeInfo(volume == 0, volume);
+    } else {
+      tempVol = new VolumeInfo(false, 1f);
+    }
+
+    this.volumeInfo.setTo(tempVol.isMute(), tempVol.getVolume());
+    updateVolumeButtons();
+  }
+
+  @Override protected void onVisibilityChanged(@NonNull View changedView, int visibility) {
+    super.onVisibilityChanged(changedView, visibility);
+    if (changedView == this) updateVolumeButtons();
+  }
+
+  @SuppressWarnings("ConstantConditions") //
+  void updateVolumeButtons() {
+    if (!isVisible() || !ViewCompat.isAttachedToWindow(this)) {
+      return;
+    }
+    boolean requestButtonFocus = false;
+    // if muted then show volumeOffButton, or else show volumeUpButton
+    boolean muted = volumeInfo.isMute();
+    if (volumeOffButton != null) {
+      requestButtonFocus |= muted && volumeOffButton.isFocused();
+      volumeOffButton.setVisibility(muted ? View.VISIBLE : View.GONE);
+    }
+    if (volumeUpButton != null) {
+      requestButtonFocus |= !muted && volumeUpButton.isFocused();
+      volumeUpButton.setVisibility(!muted ? View.VISIBLE : View.GONE);
+    }
+
+    if (volumeBar != null) {
+      volumeBar.setDuration(100);
+      volumeBar.setPosition(muted ? 0 : (long) (volumeInfo.getVolume() * 100));
+    }
+
+    if (requestButtonFocus) {
+      requestButtonFocus();
+    }
+
+    // A hack to access PlayerControlView's hideAfterTimeout. Don't want to re-implement it.
+    // Reflection happens once for all instances, so it should not affect the performance.
+    if (!hideMethodFetched) {
+      try {
+        hideAfterTimeoutMethod = PlayerControlView.class.getDeclaredMethod("hideAfterTimeout");
+        hideAfterTimeoutMethod.setAccessible(true);
+      } catch (NoSuchMethodException e) {
+        e.printStackTrace();
+      }
+      hideMethodFetched = true;
+    }
+
+    if (hideAfterTimeoutMethod != null) {
+      try {
+        hideAfterTimeoutMethod.invoke(this);
+      } catch (IllegalAccessException e) {
+        e.printStackTrace();
+      } catch (InvocationTargetException e) {
+        e.printStackTrace();
+      }
+    }
+  }
+
+  private void requestButtonFocus() {
+    boolean muted = volumeInfo.isMute();
+    if (!muted && volumeUpButton != null) {
+      volumeUpButton.requestFocus();
+    } else if (muted && volumeOffButton != null) {
+      volumeOffButton.requestFocus();
+    }
+  }
+
+  void dispatchOnScrubStart() {
+    // Fetch the 'hideAction' Runnable from super class. We need this to synchronize the show/hide
+    // behaviour when user does something.
+    if (!hideActionFetched) {
+      try {
+        hideActionField = PlayerControlView.class.getDeclaredField("hideAction");
+        hideActionField.setAccessible(true);
+      } catch (NoSuchFieldException e) {
+        e.printStackTrace();
+      }
+      hideActionFetched = true;
+    }
+
+    if (hideActionField != null) {
+      try {
+        removeCallbacks((Runnable) hideActionField.get(this));
+      } catch (IllegalAccessException e) {
+        e.printStackTrace();
+      }
+    }
+  }
+
+  // Scrub Move will always modify actual Volume, there is no 'mute-with-non-zero-volume' state.
+  void dispatchOnScrubMove(long position) {
+    if (position > 100) position = 100;
+    if (position < 0) position = 0;
+
+    float actualVolume = position / (float) 100;
+    this.volumeInfo.setTo(actualVolume == 0, actualVolume);
+    if (getPlayer() instanceof SimpleExoPlayer) {
+      ToroExo.setVolumeInfo((SimpleExoPlayer) getPlayer(), this.volumeInfo);
+    }
+
+    updateVolumeButtons();
+  }
+
+  void dispatchOnScrubStop(long position) {
+    this.dispatchOnScrubMove(position);
+  }
+
+  private class ComponentListener
+      implements OnClickListener, TimeBar.OnScrubListener, ToroPlayer.OnVolumeChangeListener {
+
+    ComponentListener() {
+    }
+
+    @Override public void onClick(View v) {
+      Player player = ToroControlView.super.getPlayer();
+      if (!(player instanceof SimpleExoPlayer)) return;
+      if (v == volumeOffButton) {  // click to vol Off --> unmute
+        volumeInfo.setTo(false, volumeInfo.getVolume());
+      } else if (v == volumeUpButton) {  // click to vol Up --> mute
+        volumeInfo.setTo(true, volumeInfo.getVolume());
+      }
+      ToroExo.setVolumeInfo((SimpleExoPlayer) player, volumeInfo);
+      updateVolumeButtons();
+    }
+
+    /// TimeBar.OnScrubListener
+
+    @Override public void onScrubStart(TimeBar timeBar, long position) {
+      dispatchOnScrubStart();
+    }
+
+    @Override public void onScrubMove(TimeBar timeBar, long position) {
+      dispatchOnScrubMove(position);
+    }
+
+    @Override public void onScrubStop(TimeBar timeBar, long position, boolean canceled) {
+      dispatchOnScrubStop(position);
+    }
+
+    /// ToroPlayer.OnVolumeChangeListener
+
+    @Override public void onVolumeChanged(@NonNull VolumeInfo volumeInfo) {
+      ToroControlView.this.volumeInfo.setTo(volumeInfo.isMute(), volumeInfo.getVolume());
+      updateVolumeButtons();
+    }
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/Common.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/Common.java
new file mode 100644
index 00000000..30e86ace
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/Common.java
@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.widget;
+
+import android.graphics.Point;
+import android.graphics.Rect;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.annotation.RestrictTo;
+import androidx.recyclerview.widget.RecyclerView;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+
+/**
+ * @author eneim | 6/2/17.
+ *
+ * A hub for internal convenient methods.
+ */
+
+@SuppressWarnings({ "unused", "WeakerAccess" }) //
+@RestrictTo(RestrictTo.Scope.LIBRARY) //
+final class Common {
+
+  private static final String TAG = "ToroLib:Common";
+  // Keep static values to reduce instance initialization. We don't need to access its value.
+  private static final Rect dummyRect = new Rect();
+  private static final Point dummyPoint = new Point();
+
+  interface Filter<T> {
+
+    boolean accept(T target);
+  }
+
+  static int compare(int x, int y) {
+    //noinspection UseCompareMethod
+    return (x < y) ? -1 : ((x == y) ? 0 : 1);
+  }
+
+  static long max(Long... numbers) {
+    List<Long> list = Arrays.asList(numbers);
+    return Collections.<Long>max(list);
+  }
+
+  static Comparator<ToroPlayer> ORDER_COMPARATOR = new Comparator<ToroPlayer>() {
+    @Override public int compare(ToroPlayer o1, ToroPlayer o2) {
+      return Common.compare(o1.getPlayerOrder(), o2.getPlayerOrder());
+    }
+  };
+
+  static final Comparator<Integer> ORDER_COMPARATOR_INT = new Comparator<Integer>() {
+    @Override public int compare(Integer o1, Integer o2) {
+      return o1.compareTo(o2);
+    }
+  };
+
+  static boolean allowsToPlay(@NonNull ToroPlayer player) {
+    dummyRect.setEmpty();
+    dummyPoint.set(0, 0);
+    boolean valid = player instanceof RecyclerView.ViewHolder;  // Should be true
+    if (valid) valid = ((RecyclerView.ViewHolder) player).itemView.getParent() != null;
+    if (valid) valid = player.getPlayerView().getGlobalVisibleRect(dummyRect, dummyPoint);
+    return valid;
+  }
+
+  @Nullable static <T> T findFirst(List<T> source, Filter<T> filter) {
+    for (T t : source) {
+      if (filter.accept(t)) return t;
+    }
+
+    return null;
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/Container.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/Container.java
new file mode 100644
index 00000000..bf5958cf
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/Container.java
@@ -0,0 +1,1137 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.widget;
+
+import static android.content.Context.POWER_SERVICE;
+import static ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil.checkNotNull;
+import static ml.docilealligator.infinityforreddit.videoautoplay.widget.Common.max;
+
+import android.app.Activity;
+import android.content.Context;
+import android.graphics.Rect;
+import android.os.Handler;
+import android.os.Message;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.os.PowerManager;
+import android.util.AttributeSet;
+import android.util.Log;
+import android.util.SparseArray;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.ViewTreeObserver.OnGlobalLayoutListener;
+
+import androidx.annotation.CallSuper;
+import androidx.annotation.ColorInt;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.coordinatorlayout.widget.CoordinatorLayout;
+import androidx.core.view.WindowInsetsCompat;
+import androidx.customview.view.AbsSavedState;
+import androidx.recyclerview.widget.RecyclerView;
+
+import java.lang.ref.WeakReference;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.CacheManager;
+import ml.docilealligator.infinityforreddit.videoautoplay.PlayerDispatcher;
+import ml.docilealligator.infinityforreddit.videoautoplay.PlayerSelector;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.RemoveIn;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+
+/**
+ * A custom {@link RecyclerView} that is capable of managing and controlling the {@link ToroPlayer}s'
+ * playback behaviour.
+ *
+ * A client wish to have the auto playback behaviour should replace the normal use of
+ * {@link RecyclerView} with {@link Container}.
+ *
+ * By default, {@link Container} doesn't support playback position saving/restoring. This is
+ * because {@link Container} has no idea about the uniqueness of media content those are being
+ * played. This can be archived by supplying {@link Container} with a valid {@link CacheManager}. A
+ * {@link CacheManager} will help providing the uniqueness of Medias by which it can correctly
+ * save/restore the playback state of a specific media item. Setup this can be done using
+ * {@link Container#setCacheManager(CacheManager)}.
+ *
+ * {@link Container} uses {@link PlayerSelector} to control the {@link ToroPlayer}. A
+ * {@link PlayerSelector} will be asked to select which {@link ToroPlayer} to start playback, and
+ * those are not selected will be paused. By default, it uses {@link PlayerSelector#DEFAULT}.
+ * Custom {@link PlayerSelector} can be set via {@link Container#setPlayerSelector(PlayerSelector)}.
+ *
+ * @author eneim | 5/31/17.
+ */
+
+@SuppressWarnings({ "unused", "ConstantConditions" }) //
+public class Container extends RecyclerView {
+
+  private static final String TAG = "ToroLib:Container";
+
+  static final int SOME_BLINKS = 50;  // 3 frames ...
+
+  /* package */ final PlayerManager playerManager;
+  /* package */ final ChildLayoutChangeListener childLayoutChangeListener;
+  /* package */ PlayerDispatcher playerDispatcher = PlayerDispatcher.DEFAULT;
+  /* package */ RecyclerListenerImpl recyclerListener;  // null = not attached/detached
+  /* package */ PlayerSelector playerSelector = PlayerSelector.DEFAULT;   // null = do nothing
+  /* package */ Handler animatorFinishHandler;  // null = not attached/detached
+  /* package */ BehaviorCallback behaviorCallback;
+
+  public Container(Context context) {
+    this(context, null);
+  }
+
+  public Container(Context context, @Nullable AttributeSet attrs) {
+    this(context, attrs, 0);
+  }
+
+  public Container(Context context, @Nullable AttributeSet attrs, int defStyle) {
+    super(context, attrs, defStyle);
+    playerManager = new PlayerManager();
+    childLayoutChangeListener = new ChildLayoutChangeListener(this);
+    requestDisallowInterceptTouchEvent(true);
+  }
+
+  @Override public final void setRecyclerListener(RecyclerListener listener) {
+    if (recyclerListener == null) recyclerListener = new RecyclerListenerImpl(this);
+    recyclerListener.delegate = listener;
+    super.setRecyclerListener(recyclerListener);
+  }
+
+  @CallSuper @Override protected void onAttachedToWindow() {
+    super.onAttachedToWindow();
+    if (getAdapter() != null) dataObserver.registerAdapter(getAdapter());
+    if (animatorFinishHandler == null) {
+      animatorFinishHandler = new Handler(new AnimatorHelper(this));
+    }
+
+    PowerManager powerManager = (PowerManager) getContext().getSystemService(POWER_SERVICE);
+    if (powerManager != null && powerManager.isScreenOn()) {
+      this.screenState = View.SCREEN_STATE_ON;
+    } else {
+      this.screenState = View.SCREEN_STATE_OFF;
+    }
+
+    /* setRecyclerListener can be called before this, it is considered as user-setup */
+    if (recyclerListener == null) {
+      recyclerListener = new RecyclerListenerImpl(this);
+      recyclerListener.delegate = NULL; // mark as it is set by Toro, not user.
+      super.setRecyclerListener(recyclerListener);  // must be a super call
+    }
+
+    playbackInfoCache.onAttach();
+    playerManager.onAttach();
+
+    ViewGroup.LayoutParams params = getLayoutParams();
+    if (params instanceof CoordinatorLayout.LayoutParams) {
+      CoordinatorLayout.Behavior behavior = ((CoordinatorLayout.LayoutParams) params).getBehavior();
+      if (behavior instanceof Behavior) {
+        ((Behavior) behavior).onViewAttached(this);
+      }
+    }
+  }
+
+  @CallSuper @Override protected void onDetachedFromWindow() {
+    super.onDetachedFromWindow();
+    ViewGroup.LayoutParams params = getLayoutParams();
+    if (params instanceof CoordinatorLayout.LayoutParams) {
+      CoordinatorLayout.Behavior behavior = ((CoordinatorLayout.LayoutParams) params).getBehavior();
+      if (behavior instanceof Behavior) {
+        ((Behavior) behavior).onViewDetached(this);
+      }
+    }
+
+    if (recyclerListener != null && recyclerListener.delegate == NULL) {  // set by Toro, not user.
+      super.setRecyclerListener(null);  // must be a super call
+      recyclerListener = null;
+    }
+
+    if (animatorFinishHandler != null) {
+      animatorFinishHandler.removeCallbacksAndMessages(null);
+      animatorFinishHandler = null;
+    }
+
+    List<ToroPlayer> players = playerManager.getPlayers();
+    if (!players.isEmpty()) {
+      for (int size = players.size(), i = size - 1; i >= 0; i--) {
+        ToroPlayer player = players.get(i);
+        if (player.isPlaying()) {
+          this.savePlaybackInfo(player.getPlayerOrder(), player.getCurrentPlaybackInfo());
+          playerManager.pause(player);
+        }
+        playerManager.release(player);
+      }
+      playerManager.clear();
+    }
+    playerManager.onDetach();
+    playbackInfoCache.onDetach();
+    dataObserver.registerAdapter(null);
+    childLayoutChangeListener.containerRef.clear();
+  }
+
+  /**
+   * Filter current managed {@link ToroPlayer}s using {@link Filter}. Result is sorted by Player
+   * order obtained from {@link ToroPlayer#getPlayerOrder()}.
+   *
+   * @param filter the {@link Filter} to a {@link ToroPlayer}.
+   * @return list of players accepted by {@link Filter}. Empty list if there is no available player.
+   */
+  @NonNull public final List<ToroPlayer> filterBy(Filter filter) {
+    List<ToroPlayer> result = new ArrayList<>();
+    for (ToroPlayer player : playerManager.getPlayers()) {
+      if (filter.accept(player)) result.add(player);
+    }
+    Collections.sort(result, Common.ORDER_COMPARATOR);
+    return result;
+  }
+
+  // This method is called when:
+  // [1] A ViewHolder is newly created, bound and then attached to RecyclerView.
+  // [2] A ViewHolder is detached before, but still in bound state, not be recycled,
+  // and now be re-attached to RecyclerView.
+  // In either cases, PlayerManager should not manage the ViewHolder before this point.
+  @CallSuper @Override public void onChildAttachedToWindow(@NonNull final View child) {
+    super.onChildAttachedToWindow(child);
+    child.addOnLayoutChangeListener(childLayoutChangeListener);
+    final ViewHolder holder = getChildViewHolder(child);
+    if (!(holder instanceof ToroPlayer)) return;
+
+    final ToroPlayer player = (ToroPlayer) holder;
+    final View playerView = player.getPlayerView();
+    if (playerView == null) {
+      throw new NullPointerException("Expected non-null playerView, found null for: " + player);
+    }
+
+    playbackInfoCache.onPlayerAttached(player);
+    if (playerManager.manages(player)) {
+      // I don't expect this to be called. If this happens, make sure to note the scenario.
+      Log.w(TAG, "!!Already managed: player = [" + player + "]");
+      // Only if container is in idle state and player is not playing.
+      if (getScrollState() == SCROLL_STATE_IDLE && !player.isPlaying()) {
+        playerManager.play(player, playerDispatcher);
+      }
+    } else {
+      // LeakCanary report a leak of OnGlobalLayoutListener but I cannot figure out why ...
+      child.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
+        @Override public void onGlobalLayout() {
+          child.getViewTreeObserver().removeOnGlobalLayoutListener(this);
+          if (Common.allowsToPlay(player)) {
+            if (playerManager.attachPlayer(player)) {
+              dispatchUpdateOnAnimationFinished(false);
+            }
+          }
+        }
+      });
+    }
+  }
+
+  @CallSuper @Override public void onChildDetachedFromWindow(@NonNull View child) {
+    super.onChildDetachedFromWindow(child);
+    child.removeOnLayoutChangeListener(childLayoutChangeListener);
+    ViewHolder holder = getChildViewHolder(child);
+    if (!(holder instanceof ToroPlayer)) return;
+    final ToroPlayer player = (ToroPlayer) holder;
+
+    boolean playerManaged = playerManager.manages(player);
+    if (player.isPlaying()) {
+      if (!playerManaged) {
+        player.pause(); // Unstable state, so forcefully pause this by itself.
+        /* throw new IllegalStateException(
+            "Player is playing while it is not in managed state: " + player); */
+      }
+      this.savePlaybackInfo(player.getPlayerOrder(), player.getCurrentPlaybackInfo());
+      playerManager.pause(player);
+    }
+    if (playerManaged) {
+      playerManager.detachPlayer(player);
+    }
+    playbackInfoCache.onPlayerDetached(player);
+    // RecyclerView#onChildDetachedFromWindow(View) is called after other removal finishes, so
+    // sometime it happens after all Animation, but we also need to update playback here.
+    // If there is no anymore child view, this call will end early.
+    dispatchUpdateOnAnimationFinished(true);
+    // finally release the player
+    // if player manager could not manager player, release by itself.
+    if (!playerManager.release(player)) player.release();
+  }
+
+  @CallSuper @Override public void onScrollStateChanged(int state) {
+    super.onScrollStateChanged(state);
+    // Need to handle the dead playback even when the Container is still scrolling/flinging.
+    List<ToroPlayer> players = playerManager.getPlayers();
+    // 1. Find players those are managed but not qualified to play anymore.
+    for (int i = 0, size = players.size(); i < size; i++) {
+      ToroPlayer player = players.get(i);
+      if (Common.allowsToPlay(player)) continue;
+      if (player.isPlaying()) {
+        this.savePlaybackInfo(player.getPlayerOrder(), player.getCurrentPlaybackInfo());
+        playerManager.pause(player);
+      }
+      if (!playerManager.release(player)) player.release();
+      playerManager.detachPlayer(player);
+    }
+
+    // 2. Refresh the good players list.
+    LayoutManager layout = super.getLayoutManager();
+    // current number of visible 'Virtual Children', or zero if there is no LayoutManager available.
+    int childCount = layout != null ? layout.getChildCount() : 0;
+    if (childCount <= 0 || state != SCROLL_STATE_IDLE) {
+      playerManager.deferPlaybacks();
+      return;
+    }
+
+    for (int i = 0; i < childCount; i++) {
+      View child = layout.getChildAt(i);
+      ViewHolder holder = super.getChildViewHolder(child);
+      if (holder instanceof ToroPlayer) {
+        ToroPlayer player = (ToroPlayer) holder;
+        // Check candidate's condition
+        if (Common.allowsToPlay(player)) {
+          if (!playerManager.manages(player)) {
+            playerManager.attachPlayer(player);
+          }
+          // Don't check the attach result, because the player may be managed already.
+          if (!player.isPlaying()) {  // not playing or not ready to play.
+            playerManager.initialize(player, Container.this);
+          }
+        }
+      }
+    }
+
+    final List<ToroPlayer> source = playerManager.getPlayers();
+    int count = source.size();
+    if (count < 1) return;  // No available player, return.
+
+    List<ToroPlayer> candidates = new ArrayList<>();
+    for (int i = 0; i < count; i++) {
+      ToroPlayer player = source.get(i);
+      if (player.wantsToPlay()) candidates.add(player);
+    }
+    Collections.sort(candidates, Common.ORDER_COMPARATOR);
+
+    Collection<ToroPlayer> toPlay = playerSelector != null ? playerSelector.select(this, candidates)
+        : Collections.<ToroPlayer>emptyList();
+    for (ToroPlayer player : toPlay) {
+      if (!player.isPlaying()) playerManager.play(player, playerDispatcher);
+    }
+
+    source.removeAll(toPlay);
+    // Now 'source' contains only ones need to be paused.
+    for (ToroPlayer player : source) {
+      if (player.isPlaying()) {
+        this.savePlaybackInfo(player.getPlayerOrder(), player.getCurrentPlaybackInfo());
+        playerManager.pause(player);
+      }
+    }
+  }
+
+  /**
+   * Setup a {@link PlayerSelector}. Set a {@code null} {@link PlayerSelector} will stop all
+   * playback.
+   *
+   * @param playerSelector new {@link PlayerSelector} for this {@link Container}.
+   */
+  public final void setPlayerSelector(@Nullable PlayerSelector playerSelector) {
+    if (this.playerSelector == playerSelector) return;
+    this.playerSelector = playerSelector;
+    // dispatchUpdateOnAnimationFinished(true); // doesn't work well :(
+    // Immediately update.
+    this.onScrollStateChanged(SCROLL_STATE_IDLE);
+  }
+
+  /**
+   * Get current {@link PlayerSelector}. Can be {@code null}.
+   *
+   * @return current {@link #playerSelector}
+   */
+  @Nullable public final PlayerSelector getPlayerSelector() {
+    return playerSelector;
+  }
+
+  public final void setPlayerDispatcher(@NonNull PlayerDispatcher playerDispatcher) {
+    this.playerDispatcher = checkNotNull(playerDispatcher);
+  }
+
+  /** Define the callback that to be used later by {@link Behavior} if setup. */
+  public final void setBehaviorCallback(@Nullable BehaviorCallback behaviorCallback) {
+    this.behaviorCallback = behaviorCallback;
+  }
+
+  ////// Handle update after data change animation
+
+  long getMaxAnimationDuration() {
+    ItemAnimator animator = getItemAnimator();
+    if (animator == null) return SOME_BLINKS;
+    return max(animator.getAddDuration(), animator.getMoveDuration(), animator.getRemoveDuration(),
+        animator.getChangeDuration());
+  }
+
+  void dispatchUpdateOnAnimationFinished(boolean immediate) {
+    if (getScrollState() != SCROLL_STATE_IDLE) return;
+    if (animatorFinishHandler == null) return;
+    final long duration = immediate ? SOME_BLINKS : getMaxAnimationDuration();
+    if (getItemAnimator() != null) {
+      getItemAnimator().isRunning(new ItemAnimator.ItemAnimatorFinishedListener() {
+        @Override public void onAnimationsFinished() {
+          animatorFinishHandler.removeCallbacksAndMessages(null);
+          animatorFinishHandler.sendEmptyMessageDelayed(-1, duration);
+        }
+      });
+    } else {
+      animatorFinishHandler.removeCallbacksAndMessages(null);
+      animatorFinishHandler.sendEmptyMessageDelayed(-1, duration);
+    }
+  }
+
+  ////// Adapter Data Observer setup
+
+  /**
+   * See {@link ToroDataObserver}
+   */
+  private final ToroDataObserver dataObserver = new ToroDataObserver();
+
+  /**
+   * See {@link Adapter#registerAdapterDataObserver(AdapterDataObserver)}
+   * See {@link Adapter#unregisterAdapterDataObserver(AdapterDataObserver)}
+   */
+  @CallSuper @Override public void setAdapter(Adapter adapter) {
+    super.setAdapter(adapter);
+    dataObserver.registerAdapter(adapter);
+  }
+
+  /**
+   * See {@link Container#setAdapter(Adapter)}
+   */
+  @CallSuper @Override public void swapAdapter(Adapter adapter,
+      boolean removeAndRecycleExistingViews) {
+    super.swapAdapter(adapter, removeAndRecycleExistingViews);
+    dataObserver.registerAdapter(adapter);
+  }
+
+  //// PlaybackInfo Cache implementation
+  /* pkg */ final PlaybackInfoCache playbackInfoCache = new PlaybackInfoCache(this);
+  /* pkg */ Initializer playerInitializer = Initializer.DEFAULT;
+  private CacheManager cacheManager = null; // null by default
+
+  public final void setPlayerInitializer(@NonNull Initializer playerInitializer) {
+    this.playerInitializer = playerInitializer;
+  }
+
+  /**
+   * Save {@link PlaybackInfo} for the current {@link ToroPlayer} of a specific order.
+   * If called with {@link PlaybackInfo#SCRAP}, it is a hint that the Player is completed and need
+   * to be re-initialized.
+   *
+   * @param order order of the {@link ToroPlayer}.
+   * @param playbackInfo current {@link PlaybackInfo} of the {@link ToroPlayer}. Null info will be ignored.
+   */
+  public final void savePlaybackInfo(int order, @Nullable PlaybackInfo playbackInfo) {
+    if (playbackInfo != null) playbackInfoCache.savePlaybackInfo(order, playbackInfo);
+  }
+
+  /**
+   * Get the cached {@link PlaybackInfo} at a specific order.
+   *
+   * @param order order of the {@link ToroPlayer} to get the cached {@link PlaybackInfo}.
+   * @return cached {@link PlaybackInfo} if available, a new one if there is no cached one.
+   */
+  @NonNull public final PlaybackInfo getPlaybackInfo(int order) {
+    return playbackInfoCache.getPlaybackInfo(order);
+  }
+
+  /**
+   * Get current list of {@link ToroPlayer}s' orders whose {@link PlaybackInfo} are cached.
+   * Returning an empty list will disable the save/restore of player's position.
+   *
+   * @return list of {@link ToroPlayer}s' orders.
+   * @deprecated Use {@link #getLatestPlaybackInfos()} for the same purpose.
+   */
+  @RemoveIn(version = "3.6.0") @Deprecated  //
+  @NonNull public List<Integer> getSavedPlayerOrders() {
+    return new ArrayList<>(playbackInfoCache.coldKeyToOrderMap.keySet());
+  }
+
+  /**
+   * Get a {@link SparseArray} contains cached {@link PlaybackInfo} of {@link ToroPlayer}s managed
+   * by this {@link Container}. If there is non-null {@link CacheManager}, this method should
+   * return the list of all {@link PlaybackInfo} cached by {@link PlaybackInfoCache}, otherwise,
+   * this method returns current {@link PlaybackInfo} of attached {@link ToroPlayer}s only.
+   */
+  @NonNull public SparseArray<PlaybackInfo> getLatestPlaybackInfos() {
+    SparseArray<PlaybackInfo> cache = new SparseArray<>();
+    List<ToroPlayer> activePlayers = this.filterBy(Container.Filter.PLAYING);
+    // This will update hotCache and coldCache if they are available.
+    for (ToroPlayer player : activePlayers) {
+      this.savePlaybackInfo(player.getPlayerOrder(), player.getCurrentPlaybackInfo());
+    }
+
+    if (cacheManager == null) {
+      if (playbackInfoCache.hotCache != null) {
+        for (Map.Entry<Integer, PlaybackInfo> entry : playbackInfoCache.hotCache.entrySet()) {
+          cache.put(entry.getKey(), entry.getValue());
+        }
+      }
+    } else {
+      for (Map.Entry<Integer, Object> entry : playbackInfoCache.coldKeyToOrderMap.entrySet()) {
+        cache.put(entry.getKey(), playbackInfoCache.coldCache.get(entry.getValue()));
+      }
+    }
+
+    return cache;
+  }
+
+  /**
+   * Set a {@link CacheManager} to this {@link Container}. A {@link CacheManager} will
+   * allow this {@link Container} to save/restore {@link PlaybackInfo} on various states or life
+   * cycle events. Setting a {@code null} {@link CacheManager} will remove that ability.
+   * {@link Container} doesn't have a non-null {@link CacheManager} by default.
+   *
+   * Setting this while there is a {@code non-null} {@link CacheManager} available will clear
+   * current {@link PlaybackInfo} cache.
+   *
+   * @param cacheManager The {@link CacheManager} to set to the {@link Container}.
+   */
+  public final void setCacheManager(@Nullable CacheManager cacheManager) {
+    if (this.cacheManager == cacheManager) return;
+    this.playbackInfoCache.clearCache();
+    this.cacheManager = cacheManager;
+  }
+
+  /**
+   * Get current {@link CacheManager} of the {@link Container}.
+   *
+   * @return current {@link CacheManager} of the {@link Container}. Can be {@code null}.
+   */
+  @Nullable public final CacheManager getCacheManager() {
+    return cacheManager;
+  }
+
+  /**
+   * Temporary save current playback infos when the App is stopped but not re-created. (For example:
+   * User press App Stack). If not {@code empty} then user is back from a living-but-stopped state.
+   */
+  final SparseArray<PlaybackInfo> tmpStates = new SparseArray<>();
+
+  /**
+   * In case user press "App Stack" button, this View's window will have visibility change from
+   * {@link #VISIBLE} to {@link #INVISIBLE} to {@link #GONE}. When user is back from that state,
+   * the visibility changes from {@link #GONE} to {@link #INVISIBLE} to {@link #VISIBLE}. A proper
+   * playback needs to handle this case too.
+   */
+  @CallSuper @Override protected void onWindowVisibilityChanged(int visibility) {
+    super.onWindowVisibilityChanged(visibility);
+    if (visibility == View.GONE) {
+      List<ToroPlayer> players = playerManager.getPlayers();
+      // if onSaveInstanceState is called before, source will contain no item, just fine.
+      for (ToroPlayer player : players) {
+        if (player.isPlaying()) {
+          this.savePlaybackInfo(player.getPlayerOrder(), player.getCurrentPlaybackInfo());
+          playerManager.pause(player);
+        }
+      }
+    } else if (visibility == View.VISIBLE) {
+      if (tmpStates.size() > 0) {
+        for (int i = 0; i < tmpStates.size(); i++) {
+          int order = tmpStates.keyAt(i);
+          PlaybackInfo playbackInfo = tmpStates.get(order);
+          this.savePlaybackInfo(order, playbackInfo);
+        }
+      }
+      tmpStates.clear();
+      dispatchUpdateOnAnimationFinished(true);
+    }
+
+    dispatchWindowVisibilityMayChange();
+  }
+
+  private int screenState;
+
+  @Override public void onScreenStateChanged(int screenState) {
+    super.onScreenStateChanged(screenState);
+    this.screenState = screenState;
+    dispatchWindowVisibilityMayChange();
+  }
+
+  @Override public void onWindowFocusChanged(boolean hasWindowFocus) {
+    super.onWindowFocusChanged(hasWindowFocus);
+    dispatchWindowVisibilityMayChange();
+  }
+
+  /**
+   * This method supports the case that by some reasons, Container should changes it behaviour not
+   * caused by any Activity recreation (so {@link #onSaveInstanceState()} and
+   * {@link #onRestoreInstanceState(Parcelable)} could not help).
+   *
+   * This method is called when:
+   * - Screen state changed.
+   * or - Window focus changed.
+   * or - Window visibility changed.
+   *
+   * For each of that event, Screen may be turned off or Window's focus state may change, we need
+   * to decide if Container should keep current playback state or change it.
+   *
+   * <strong>Discussion</strong>: In fact, we expect that: Container will be playing if the
+   * following conditions are all satisfied:
+   * - Current window is visible. (but not necessarily focused).
+   * - Container is visible in Window (partly is fine, we care about the Media player).
+   * - Container is focused in Window. (so we don't screw up other components' focuses).
+   *
+   * In lower API (eg: 16), {@link #getWindowVisibility()} always returns {@link #VISIBLE}, which
+   * cannot tell much. We need to investigate this flag in various APIs in various Scenarios.
+   */
+  private void dispatchWindowVisibilityMayChange() {
+    if (screenState == SCREEN_STATE_OFF) {
+      List<ToroPlayer> players = playerManager.getPlayers();
+      for (ToroPlayer player : players) {
+        if (player.isPlaying()) {
+          this.savePlaybackInfo(player.getPlayerOrder(), player.getCurrentPlaybackInfo());
+          playerManager.pause(player);
+        }
+      }
+    } else if (screenState == SCREEN_STATE_ON
+        // Container is focused in current Window
+        && hasFocus()
+        // In fact, Android 24+ supports multi-window mode in which visible Window may not have focus.
+        // In that case, other triggers are supposed to be called and we are safe here.
+        // Need further investigation if need.
+        && hasWindowFocus()) {
+      // tmpStates may be consumed already, if there is a good reason for that, so not a big deal.
+      if (tmpStates.size() > 0) {
+        for (int i = 0, size = tmpStates.size(); i < size; i++) {
+          int order = tmpStates.keyAt(i);
+          this.savePlaybackInfo(order, tmpStates.get(order));
+        }
+      }
+      tmpStates.clear();
+      dispatchUpdateOnAnimationFinished(true);
+    }
+  }
+
+  @Override protected Parcelable onSaveInstanceState() {
+    Parcelable superState = super.onSaveInstanceState();
+    List<ToroPlayer> source = playerManager.getPlayers();
+    for (ToroPlayer player : source) {
+      if (player.isPlaying()) {
+        this.savePlaybackInfo(player.getPlayerOrder(), player.getCurrentPlaybackInfo());
+        playerManager.pause(player);
+      }
+    }
+
+    final SparseArray<PlaybackInfo> states = playbackInfoCache.saveStates();
+
+    boolean recreating =
+        getContext() instanceof Activity && ((Activity) getContext()).isChangingConfigurations();
+
+    // Release current players on recreation event only.
+    // Note that there are cases where this method is called without the activity destroying/recreating.
+    // For example: in API 26 (my test mostly run on 8.0), when user click to "Current App" button,
+    // current Activity will enter the "Stop" state but not be destroyed/recreated and View hierarchy
+    // state will be saved (this method is called).
+    //
+    // We only need to release current resources when the recreation happens.
+    if (recreating) {
+      for (ToroPlayer player : source) {
+        if (!playerManager.release(player)) player.release();
+        playerManager.detachPlayer(player);
+      }
+    }
+
+    // Client must consider this behavior using CacheManager implement.
+    PlayerViewState playerViewState = new PlayerViewState(superState);
+    playerViewState.statesCache = states;
+
+    // To mark that this method was called. An activity recreation will clear this.
+    if (states != null && states.size() > 0) {
+      for (int i = 0; i < states.size(); i++) {
+        PlaybackInfo value = states.valueAt(i);
+        if (value != null) tmpStates.put(states.keyAt(i), value);
+      }
+    }
+
+    return playerViewState;
+  }
+
+  @Override protected void onRestoreInstanceState(Parcelable state) {
+    if (!(state instanceof PlayerViewState)) {
+      super.onRestoreInstanceState(state);
+      return;
+    }
+
+    PlayerViewState viewState = (PlayerViewState) state;
+    super.onRestoreInstanceState(viewState.getSuperState());
+    SparseArray<?> saveStates = viewState.statesCache;
+    if (saveStates != null) playbackInfoCache.restoreStates(saveStates);
+  }
+
+  /**
+   * Store the array of {@link PlaybackInfo} of recently cached playback. This state will be used
+   * only when {@link #cacheManager} is not {@code null}. Extension of {@link Container} must
+   * also have its own version of {@link SavedState} extends this {@link PlayerViewState}.
+   */
+  public static class PlayerViewState extends AbsSavedState {
+
+    SparseArray<?> statesCache;
+
+    /**
+     * Called by onSaveInstanceState
+     */
+    PlayerViewState(Parcelable superState) {
+      super(superState);
+    }
+
+    /**
+     * Called by CREATOR
+     */
+    PlayerViewState(Parcel in, ClassLoader loader) {
+      super(in, loader);
+      statesCache = in.readSparseArray(loader);
+    }
+
+    PlayerViewState(Parcel in) {
+      super(in);
+    }
+
+    @Override public void writeToParcel(Parcel dest, int flags) {
+      super.writeToParcel(dest, flags);
+      //noinspection unchecked
+      dest.writeSparseArray((SparseArray<Object>) statesCache);
+    }
+
+    public static final Creator<PlayerViewState> CREATOR =
+        new ClassLoaderCreator<PlayerViewState>() { // Added from API 13
+          @Override public PlayerViewState createFromParcel(Parcel in, ClassLoader loader) {
+            return new PlayerViewState(in, loader);
+          }
+
+          @Override public PlayerViewState createFromParcel(Parcel source) {
+            return new PlayerViewState(source);
+          }
+
+          @Override public PlayerViewState[] newArray(int size) {
+            return new PlayerViewState[size];
+          }
+        };
+
+    @NonNull @Override public String toString() {
+      return "Cache{" + "states=" + statesCache + '}';
+    }
+  }
+
+  private final class ToroDataObserver extends AdapterDataObserver {
+
+    private Adapter adapter;
+
+    ToroDataObserver() {
+    }
+
+    final void registerAdapter(Adapter adapter) {
+      if (this.adapter == adapter) return;
+      if (this.adapter != null) {
+        this.adapter.unregisterAdapterDataObserver(this);
+        this.adapter.unregisterAdapterDataObserver(playbackInfoCache);
+      }
+
+      this.adapter = adapter;
+      if (this.adapter != null) {
+        this.adapter.registerAdapterDataObserver(this);
+        this.adapter.registerAdapterDataObserver(playbackInfoCache);
+      }
+    }
+
+    @Override public void onChanged() {
+      dispatchUpdateOnAnimationFinished(true);
+    }
+
+    @Override public void onItemRangeChanged(int positionStart, int itemCount) {
+      dispatchUpdateOnAnimationFinished(false);
+    }
+
+    @Override public void onItemRangeInserted(int positionStart, int itemCount) {
+      dispatchUpdateOnAnimationFinished(false);
+    }
+
+    @Override public void onItemRangeRemoved(int positionStart, int itemCount) {
+      dispatchUpdateOnAnimationFinished(false);
+    }
+
+    @Override public void onItemRangeMoved(int fromPosition, int toPosition, int itemCount) {
+      dispatchUpdateOnAnimationFinished(false);
+    }
+  }
+
+  /**
+   * A {@link Handler.Callback} that will fake a scroll with {@link #SCROLL_STATE_IDLE} to refresh
+   * all the playback. This is relatively expensive.
+   */
+  private static class AnimatorHelper implements Handler.Callback {
+
+    @NonNull private final Container container;
+
+    AnimatorHelper(@NonNull Container container) {
+      this.container = container;
+    }
+
+    @Override public boolean handleMessage(Message msg) {
+      this.container.onScrollStateChanged(SCROLL_STATE_IDLE);
+      return true;
+    }
+  }
+
+  private static class RecyclerListenerImpl implements RecyclerView.RecyclerListener {
+
+    final Container container;
+    RecyclerListener delegate;
+
+    RecyclerListenerImpl(@NonNull Container container) {
+      this.container = container;
+    }
+
+    @Override public void onViewRecycled(@NonNull ViewHolder holder) {
+      if (this.delegate != null) this.delegate.onViewRecycled(holder);
+      if (holder instanceof ToroPlayer) {
+        ToroPlayer player = (ToroPlayer) holder;
+        this.container.playbackInfoCache.onPlayerRecycled(player);
+        this.container.playerManager.recycle(player);
+      }
+    }
+  }
+
+  // This instance is to mark a RecyclerListenerImpl to be set by Toro, not by user.
+  private static final RecyclerListener NULL = new RecyclerListener() {
+    @Override public void onViewRecycled(@NonNull ViewHolder holder) {
+      // No-ops
+    }
+  };
+
+  /**
+   * An utility interface, used by {@link Container} to filter for {@link ToroPlayer}.
+   */
+  public interface Filter {
+
+    /**
+     * Check a {@link ToroPlayer} for a condition.
+     *
+     * @param player the {@link ToroPlayer} to check.
+     * @return {@code true} if this accepts the {@link ToroPlayer}, {@code false} otherwise.
+     */
+    boolean accept(@NonNull ToroPlayer player);
+
+    /**
+     * A built-in {@link Filter} that accepts only {@link ToroPlayer} that is playing.
+     */
+    Filter PLAYING = new Filter() {
+      @Override public boolean accept(@NonNull ToroPlayer player) {
+        return player.isPlaying();
+      }
+    };
+
+    /**
+     * A built-in {@link Filter} that accepts only {@link ToroPlayer} that is managed by Container.
+     * Actually any {@link ToroPlayer} to be filtered is already managed.
+     */
+    Filter MANAGING = new Filter() {
+      @Override public boolean accept(@NonNull ToroPlayer player) {
+        return true;
+      }
+    };
+  }
+
+  /**
+   * This behaviour is to catch the touch/fling/scroll caused by other children of
+   * {@link CoordinatorLayout}. We try to acknowledge user actions by intercepting the call but not
+   * consume the events.
+   *
+   * This class helps solve the issue when Client has a {@link Container} inside a
+   * {@link CoordinatorLayout} together with an {@link AppBarLayout} whose direct child is a
+   * {@link CollapsingToolbarLayout} (which is 'scrollable'). This 'scroll behavior' is not the
+   * same as Container's natural scroll. When user 'scrolls' to collapse or expand the {@link
+   * AppBarLayout}, {@link CoordinatorLayout} will offset the {@link Container} to make room for
+   * {@link AppBarLayout}, in which {@link Container} will not receive any scrolling event update,
+   * but just be shifted along the scrolling axis. This behavior results in a bad case that after
+   * the AppBarLayout collapse its direct {@link CollapsingToolbarLayout}, the Video may be fully
+   * visible, but because the Container has no way to know about that event, there is no playback
+   * update.
+   *
+   * @since 3.4.2
+   */
+  public static class Behavior extends CoordinatorLayout.Behavior<Container>
+      implements Handler.Callback {
+
+    @NonNull final CoordinatorLayout.Behavior<? super Container> delegate;
+    @Nullable BehaviorCallback callback;
+
+    static final int EVENT_IDLE = 1;
+    static final int EVENT_SCROLL = 2;
+    static final int EVENT_TOUCH = 3;
+    static final int EVENT_DELAY = 150;
+
+    final AtomicBoolean scrollConsumed = new AtomicBoolean(false);
+
+    Handler handler;
+
+    void onViewAttached(Container container) {
+      if (handler == null) handler = new Handler(this);
+      this.callback = container.behaviorCallback;
+    }
+
+    void onViewDetached(Container container) {
+      if (handler != null) {
+        handler.removeCallbacksAndMessages(null);
+        handler = null;
+      }
+      this.callback = null;
+    }
+
+    @Override public boolean handleMessage(Message msg) {
+      if (callback == null) return true;
+      switch (msg.what) {
+        case EVENT_SCROLL:
+        case EVENT_TOUCH:
+          scrollConsumed.set(false);
+          handler.removeMessages(EVENT_IDLE);
+          handler.sendEmptyMessageDelayed(EVENT_IDLE, EVENT_DELAY);
+          break;
+        case EVENT_IDLE:
+          // idle --> consume it.
+          if (!scrollConsumed.getAndSet(true)) callback.onFinishInteraction();
+          break;
+      }
+      return true;
+    }
+
+    /* No default constructors. Using this class from xml will result in error. */
+
+    // public Behavior() {
+    // }
+    //
+    // public Behavior(Context context, AttributeSet attrs) {
+    //   super(context, attrs);
+    // }
+
+    public Behavior(@NonNull CoordinatorLayout.Behavior<Container> delegate) {
+      this.delegate = checkNotNull(delegate, "Behavior is null.");
+    }
+
+    /// We only need to intercept the following 3 methods:
+
+    @Override public boolean onInterceptTouchEvent(@NonNull CoordinatorLayout parent,
+        @NonNull Container child, @NonNull MotionEvent ev) {
+      if (this.handler != null) {
+        this.handler.removeCallbacksAndMessages(null);
+        this.handler.sendEmptyMessage(EVENT_TOUCH);
+      }
+      return delegate.onInterceptTouchEvent(parent, child, ev);
+    }
+
+    @Override
+    public boolean onTouchEvent(@NonNull CoordinatorLayout parent, @NonNull Container child,
+        @NonNull MotionEvent ev) {
+      if (this.handler != null) {
+        this.handler.removeCallbacksAndMessages(null);
+        this.handler.sendEmptyMessage(EVENT_TOUCH);
+      }
+      return delegate.onTouchEvent(parent, child, ev);
+    }
+
+    @Override
+    public boolean onStartNestedScroll(@NonNull CoordinatorLayout layout, @NonNull Container child,
+        @NonNull View directTargetChild, @NonNull View target, int axes, int type) {
+      if (this.handler != null) {
+        this.handler.removeCallbacksAndMessages(null);
+        this.handler.sendEmptyMessage(EVENT_SCROLL);
+      }
+      return delegate.onStartNestedScroll(layout, child, directTargetChild, target, axes, type);
+    }
+
+    /// Other methods
+
+    @Override public void onAttachedToLayoutParams(@NonNull CoordinatorLayout.LayoutParams params) {
+      if (handler == null) handler = new Handler(this);
+      delegate.onAttachedToLayoutParams(params);
+    }
+
+    @Override public void onDetachedFromLayoutParams() {
+      if (handler != null) {
+        handler.removeCallbacksAndMessages(null);
+        handler = null;
+      }
+      delegate.onDetachedFromLayoutParams();
+    }
+
+    @Override @ColorInt
+    public int getScrimColor(@NonNull CoordinatorLayout parent, @NonNull Container child) {
+      return delegate.getScrimColor(parent, child);
+    }
+
+    @Override
+    public float getScrimOpacity(@NonNull CoordinatorLayout parent, @NonNull Container child) {
+      return delegate.getScrimOpacity(parent, child);
+    }
+
+    @Override public boolean blocksInteractionBelow(@NonNull CoordinatorLayout parent,
+        @NonNull Container child) {
+      return delegate.blocksInteractionBelow(parent, child);
+    }
+
+    @Override
+    public boolean layoutDependsOn(@NonNull CoordinatorLayout parent, @NonNull Container child,
+        @NonNull View dependency) {
+      return delegate.layoutDependsOn(parent, child, dependency);
+    }
+
+    @Override public boolean onDependentViewChanged(@NonNull CoordinatorLayout parent,
+        @NonNull Container child, @NonNull View dependency) {
+      return delegate.onDependentViewChanged(parent, child, dependency);
+    }
+
+    @Override
+    public void onDependentViewRemoved(@NonNull CoordinatorLayout parent, @NonNull Container child,
+        @NonNull View dependency) {
+      delegate.onDependentViewRemoved(parent, child, dependency);
+    }
+
+    @Override
+    public boolean onMeasureChild(@NonNull CoordinatorLayout parent, @NonNull Container child,
+        int parentWidthMeasureSpec, int widthUsed, int parentHeightMeasureSpec, int heightUsed) {
+      return delegate.onMeasureChild(parent, child, parentWidthMeasureSpec, widthUsed,
+          parentHeightMeasureSpec, heightUsed);
+    }
+
+    @Override
+    public boolean onLayoutChild(@NonNull CoordinatorLayout parent, @NonNull Container child,
+        int layoutDirection) {
+      return delegate.onLayoutChild(parent, child, layoutDirection);
+    }
+
+    @Override
+    public void onNestedScrollAccepted(@NonNull CoordinatorLayout layout, @NonNull Container child,
+        @NonNull View directTargetChild, @NonNull View target, int axes, int type) {
+      delegate.onNestedScrollAccepted(layout, child, directTargetChild, target, axes, type);
+    }
+
+    @Override
+    public void onStopNestedScroll(@NonNull CoordinatorLayout layout, @NonNull Container child,
+        @NonNull View target, int type) {
+      delegate.onStopNestedScroll(layout, child, target, type);
+    }
+
+    @Override
+    public void onNestedScroll(@NonNull CoordinatorLayout layout, @NonNull Container child,
+        @NonNull View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed,
+        int type) {
+      delegate.onNestedScroll(layout, child, target, dxConsumed, dyConsumed, dxUnconsumed,
+          dyUnconsumed, type);
+    }
+
+    @Override
+    public void onNestedPreScroll(@NonNull CoordinatorLayout layout, @NonNull Container child,
+        @NonNull View target, int dx, int dy, @NonNull int[] consumed, int type) {
+      delegate.onNestedPreScroll(layout, child, target, dx, dy, consumed, type);
+    }
+
+    @Override
+    public boolean onNestedFling(@NonNull CoordinatorLayout layout, @NonNull Container child,
+        @NonNull View target, float velocityX, float velocityY, boolean consumed) {
+      return delegate.onNestedFling(layout, child, target, velocityX, velocityY, consumed);
+    }
+
+    @Override
+    public boolean onNestedPreFling(@NonNull CoordinatorLayout layout, @NonNull Container child,
+        @NonNull View target, float velocityX, float velocityY) {
+      return delegate.onNestedPreFling(layout, child, target, velocityX, velocityY);
+    }
+
+    @Override @NonNull
+    public WindowInsetsCompat onApplyWindowInsets(@NonNull CoordinatorLayout layout,
+        @NonNull Container child, @NonNull WindowInsetsCompat insets) {
+      return delegate.onApplyWindowInsets(layout, child, insets);
+    }
+
+    @Override public boolean onRequestChildRectangleOnScreen(@NonNull CoordinatorLayout layout,
+        @NonNull Container child, @NonNull Rect rectangle, boolean immediate) {
+      return delegate.onRequestChildRectangleOnScreen(layout, child, rectangle, immediate);
+    }
+
+    @Override
+    public void onRestoreInstanceState(@NonNull CoordinatorLayout parent, @NonNull Container child,
+        @NonNull Parcelable state) {
+      delegate.onRestoreInstanceState(parent, child, state);
+    }
+
+    @Override public Parcelable onSaveInstanceState(@NonNull CoordinatorLayout parent,
+        @NonNull Container child) {
+      return delegate.onSaveInstanceState(parent, child);
+    }
+
+    @Override
+    public boolean getInsetDodgeRect(@NonNull CoordinatorLayout parent, @NonNull Container child,
+        @NonNull Rect rect) {
+      return delegate.getInsetDodgeRect(parent, child, rect);
+    }
+  }
+
+  /**
+   * Callback for {@link Behavior} to tell the Client that User has finished the interaction for
+   * enough amount of time, so it (the Client) should do something. Normally, we ask Container to
+   * dispatch an 'idle scroll' to refresh the player list.
+   */
+  public interface BehaviorCallback {
+
+    void onFinishInteraction();
+  }
+
+  public interface Initializer {
+
+    @NonNull PlaybackInfo initPlaybackInfo(int order);
+
+    Initializer DEFAULT = new Initializer() {
+      @NonNull @Override public PlaybackInfo initPlaybackInfo(int order) {
+        return new PlaybackInfo();
+      }
+    };
+  }
+
+  static class ChildLayoutChangeListener implements OnLayoutChangeListener {
+
+    final WeakReference<Container> containerRef;
+
+    ChildLayoutChangeListener(Container container) {
+      this.containerRef = new WeakReference<>(container);
+    }
+
+    @Override
+    public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft,
+        int oldTop, int oldRight, int oldBottom) {
+      Container container = containerRef.get();
+      if (container == null) return;
+      if (layoutDidChange(left, top, right, bottom, oldLeft, oldTop, oldRight, oldBottom)) {
+        container.dispatchUpdateOnAnimationFinished(false);
+      }
+    }
+  }
+
+  static boolean layoutDidChange(int left, int top, int right, int bottom, int oldLeft, int oldTop,
+      int oldRight, int oldBottom) {
+    return left != oldLeft || top != oldTop || right != oldRight || bottom != oldBottom;
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PlaybackInfoCache.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PlaybackInfoCache.java
new file mode 100644
index 00000000..9934779b
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PlaybackInfoCache.java
@@ -0,0 +1,402 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.widget;
+
+import static ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo.SCRAP;
+import static ml.docilealligator.infinityforreddit.videoautoplay.widget.Common.ORDER_COMPARATOR_INT;
+
+import android.annotation.SuppressLint;
+import android.util.SparseArray;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.recyclerview.widget.RecyclerView;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+import java.util.TreeMap;
+import java.util.TreeSet;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil;
+import ml.docilealligator.infinityforreddit.videoautoplay.media.PlaybackInfo;
+
+/**
+ * @author eneim (2018/04/24).
+ *
+ * Design Target:
+ *
+ * [1] Manage the {@link PlaybackInfo} of current {@link ToroPlayer}s. Should match 1-1 with the
+ * {@link ToroPlayer}s that {@link PlayerManager} is managing.
+ *
+ * [2] If a non-null {@link CacheManager} provided to the {@link Container}, this class must
+ * properly manage the {@link PlaybackInfo} of detached {@link ToroPlayer} and restore it to
+ * previous state after being re-attached.
+ */
+@SuppressWarnings({ "unused" })
+@SuppressLint("UseSparseArrays") //
+final class PlaybackInfoCache extends RecyclerView.AdapterDataObserver {
+
+  @NonNull private final Container container;
+  // Cold cache represents the map between key obtained from CacheManager and PlaybackInfo. If the
+  // CacheManager is null, this cache will hold nothing.
+  /* pkg */ HashMap<Object, PlaybackInfo> coldCache = new HashMap<>();
+
+  // Hot cache represents the map between Player's order and its PlaybackInfo. A key-value map only
+  // lives within a Player's attached state.
+  // Being a TreeMap because we need to traversal through it in order sometime.
+  /* pkg */ TreeMap<Integer, PlaybackInfo> hotCache; // only cache attached Views.
+
+  // Holds the map between Player's order and its key obtain from CacheManager.
+  /* pkg */ TreeMap<Integer, Object> coldKeyToOrderMap = new TreeMap<>(ORDER_COMPARATOR_INT);
+
+  PlaybackInfoCache(@NonNull Container container) {
+    this.container = container;
+  }
+
+  final void onAttach() {
+    hotCache = new TreeMap<>(ORDER_COMPARATOR_INT);
+  }
+
+  final void onDetach() {
+    if (hotCache != null) {
+      hotCache.clear();
+      hotCache = null;
+    }
+    coldKeyToOrderMap.clear();
+  }
+
+  final void onPlayerAttached(ToroPlayer player) {
+    int playerOrder = player.getPlayerOrder();
+    // [1] Check if there is cold cache for this player
+    Object key = getKey(playerOrder);
+    if (key != null) coldKeyToOrderMap.put(playerOrder, key);
+
+    PlaybackInfo cache = key == null ? null : coldCache.get(key);
+    if (cache == null || cache == SCRAP) {
+      // We init this even if there is no CacheManager available, because this is what User expects.
+      cache = container.playerInitializer.initPlaybackInfo(playerOrder);
+      // Only save to cold cache when there is a valid CacheManager (key is not null).
+      if (key != null) coldCache.put(key, cache);
+    }
+
+    if (hotCache != null) hotCache.put(playerOrder, cache);
+  }
+
+  // Will be called from Container#onChildViewDetachedFromWindow(View)
+  // Therefore, it may not be called on all views. For example: when user close the App, by default
+  // when RecyclerView is detached from Window, it will not call onChildViewDetachedFromWindow for
+  // its children.
+  // This method will:
+  // [1] Take current hot cache entry of the player, and put back to cold cache.
+  // [2] Remove the hot cache entry of the player.
+  final void onPlayerDetached(ToroPlayer player) {
+    int playerOrder = player.getPlayerOrder();
+    if (hotCache != null && hotCache.containsKey(playerOrder)) {
+      PlaybackInfo cache = hotCache.remove(playerOrder);
+      Object key = getKey(playerOrder);
+      if (key != null) coldCache.put(key, cache);
+    }
+  }
+
+  @SuppressWarnings("unused") final void onPlayerRecycled(ToroPlayer player) {
+    // TODO do anything here?
+  }
+
+  /// Adapter change events handling
+
+  @Override public void onChanged() {
+    if (container.getCacheManager() != null) {
+      for (Integer key : coldKeyToOrderMap.keySet()) {
+        Object cacheKey = getKey(key);
+        coldCache.put(cacheKey, SCRAP);
+        coldKeyToOrderMap.put(key, cacheKey);
+      }
+    }
+
+    if (hotCache != null) {
+      for (Integer key : hotCache.keySet()) {
+        hotCache.put(key, SCRAP);
+      }
+    }
+  }
+
+  @Override public void onItemRangeChanged(final int positionStart, final int itemCount) {
+    if (itemCount == 0) return;
+    if (container.getCacheManager() != null) {
+      Set<Integer> changedColdKeys = new TreeSet<>(ORDER_COMPARATOR_INT);
+      for (Integer key : coldKeyToOrderMap.keySet()) {
+        if (key >= positionStart && key < positionStart + itemCount) {
+          changedColdKeys.add(key);
+        }
+      }
+
+      for (Integer key : changedColdKeys) {
+        Object cacheKey = getKey(key);
+        coldCache.put(cacheKey, SCRAP);
+        coldKeyToOrderMap.put(key, cacheKey);
+      }
+    }
+
+    if (hotCache != null) {
+      Set<Integer> changedHotKeys = new TreeSet<>(ORDER_COMPARATOR_INT);
+      for (Integer key : hotCache.keySet()) {
+        if (key >= positionStart && key < positionStart + itemCount) {
+          changedHotKeys.add(key);
+        }
+      }
+
+      for (Integer key : changedHotKeys) {
+        hotCache.put(key, SCRAP);
+      }
+    }
+  }
+
+  @Override public void onItemRangeInserted(final int positionStart, final int itemCount) {
+    if (itemCount == 0) return;
+    PlaybackInfo value;
+    // Cold cache update
+    if (container.getCacheManager() != null) {
+      // [1] Take keys of old one.
+      // 1.1 Extract subset of keys only:
+      Set<Integer> changedColdKeys = new TreeSet<>(ORDER_COMPARATOR_INT);
+      for (Integer key : coldKeyToOrderMap.keySet()) {
+        if (key >= positionStart) {
+          changedColdKeys.add(key);
+        }
+      }
+
+      // 1.2 Extract entries from cold cache to a temp cache.
+      final Map<Object, PlaybackInfo> changeColdEntriesCache = new HashMap<>();
+      for (Integer key : changedColdKeys) {
+        if ((value = coldCache.remove(coldKeyToOrderMap.get(key))) != null) {
+          changeColdEntriesCache.put(key, value);
+        }
+      }
+
+      // 1.2 Update cold Cache with new keys
+      for (Integer key : changedColdKeys) {
+        coldCache.put(getKey(key + itemCount), changeColdEntriesCache.get(key));
+      }
+
+      // 1.3 Update coldKeyToOrderMap;
+      for (Integer key : changedColdKeys) {
+        coldKeyToOrderMap.put(key, getKey(key));
+      }
+    }
+
+    // [1] Remove cache if there is any appearance
+    if (hotCache != null) {
+      // [2] Shift cache by specific number
+      Map<Integer, PlaybackInfo> changedHotEntriesCache = new HashMap<>();
+      Set<Integer> changedHotKeys = new TreeSet<>(ORDER_COMPARATOR_INT);
+      for (Integer key : hotCache.keySet()) {
+        if (key >= positionStart) {
+          changedHotKeys.add(key);
+        }
+      }
+
+      for (Integer key : changedHotKeys) {
+        if ((value = hotCache.remove(key)) != null) {
+          changedHotEntriesCache.put(key, value);
+        }
+      }
+
+      for (Integer key : changedHotKeys) {
+        hotCache.put(key + itemCount, changedHotEntriesCache.get(key));
+      }
+    }
+  }
+
+  @Override public void onItemRangeRemoved(final int positionStart, final int itemCount) {
+    if (itemCount == 0) return;
+    PlaybackInfo value;
+    // Cold cache update
+    if (container.getCacheManager() != null) {
+      // [1] Take keys of old one.
+      // 1.1 Extract subset of keys only:
+      Set<Integer> changedColdKeys = new TreeSet<>(ORDER_COMPARATOR_INT);
+      for (Integer key : coldKeyToOrderMap.keySet()) {
+        if (key >= positionStart + itemCount) changedColdKeys.add(key);
+      }
+      // 1.2 Extract entries from cold cache to a temp cache.
+      final Map<Object, PlaybackInfo> changeColdEntriesCache = new HashMap<>();
+      for (Integer key : changedColdKeys) {
+        if ((value = coldCache.remove(coldKeyToOrderMap.get(key))) != null) {
+          changeColdEntriesCache.put(key, value);
+        }
+      }
+
+      // 1.2 Update cold Cache with new keys
+      for (Integer key : changedColdKeys) {
+        coldCache.put(getKey(key - itemCount), changeColdEntriesCache.get(key));
+      }
+
+      // 1.3 Update coldKeyToOrderMap;
+      for (Integer key : changedColdKeys) {
+        coldKeyToOrderMap.put(key, getKey(key));
+      }
+    }
+
+    // [1] Remove cache if there is any appearance
+    if (hotCache != null) {
+      for (int i = 0; i < itemCount; i++) {
+        hotCache.remove(positionStart + i);
+      }
+
+      // [2] Shift cache by specific number
+      Map<Integer, PlaybackInfo> changedHotEntriesCache = new HashMap<>();
+      Set<Integer> changedHotKeys = new TreeSet<>(ORDER_COMPARATOR_INT);
+      for (Integer key : hotCache.keySet()) {
+        if (key >= positionStart + itemCount) changedHotKeys.add(key);
+      }
+
+      for (Integer key : changedHotKeys) {
+        if ((value = hotCache.remove(key)) != null) {
+          changedHotEntriesCache.put(key, value);
+        }
+      }
+
+      for (Integer key : changedHotKeys) {
+        hotCache.put(key - itemCount, changedHotEntriesCache.get(key));
+      }
+    }
+  }
+
+  // Dude I wanna test this thing >.<
+  @Override public void onItemRangeMoved(final int fromPos, final int toPos, int itemCount) {
+    if (fromPos == toPos) return;
+
+    final int low = fromPos < toPos ? fromPos : toPos;
+    final int high = fromPos + toPos - low;
+    final int shift = fromPos < toPos ? -1 : 1;  // how item will be shifted due to the move
+    PlaybackInfo value;
+    // [1] Migrate cold cache.
+    if (container.getCacheManager() != null) {
+      // 1.1 Extract subset of keys only:
+      Set<Integer> changedColdKeys = new TreeSet<>(ORDER_COMPARATOR_INT);
+      for (Integer key : coldKeyToOrderMap.keySet()) {
+        if (key >= low && key <= high) changedColdKeys.add(key);
+      }
+      // 1.2 Extract entries from cold cache to a temp cache.
+      final Map<Object, PlaybackInfo> changeColdEntries = new HashMap<>();
+      for (Integer key : changedColdKeys) {
+        if ((value = coldCache.remove(coldKeyToOrderMap.get(key))) != null) {
+          changeColdEntries.put(key, value);
+        }
+      }
+
+      // 1.2 Update cold Cache with new keys
+      for (Integer key : changedColdKeys) {
+        if (key == low) {
+          coldCache.put(getKey(high), changeColdEntries.get(key));
+        } else {
+          coldCache.put(getKey(key + shift), changeColdEntries.get(key));
+        }
+      }
+
+      // 1.3 Update coldKeyToOrderMap;
+      for (Integer key : changedColdKeys) {
+        coldKeyToOrderMap.put(key, getKey(key));
+      }
+    }
+
+    // [2] Migrate hot cache.
+    if (hotCache != null) {
+      Set<Integer> changedHotKeys = new TreeSet<>(ORDER_COMPARATOR_INT);
+      for (Integer key : hotCache.keySet()) {
+        if (key >= low && key <= high) changedHotKeys.add(key);
+      }
+
+      Map<Integer, PlaybackInfo> changedHotEntriesCache = new HashMap<>();
+      for (Integer key : changedHotKeys) {
+        if ((value = hotCache.remove(key)) != null) changedHotEntriesCache.put(key, value);
+      }
+
+      for (Integer key : changedHotKeys) {
+        if (key == low) {
+          hotCache.put(high, changedHotEntriesCache.get(key));
+        } else {
+          hotCache.put(key + shift, changedHotEntriesCache.get(key));
+        }
+      }
+    }
+  }
+
+  @Nullable private Object getKey(int position) {
+    return position == RecyclerView.NO_POSITION ? null : container.getCacheManager() == null ? null
+        : container.getCacheManager().getKeyForOrder(position);
+  }
+
+  //@Nullable private Integer getOrder(Object key) {
+  //  return container.getCacheManager() == null ? null
+  //      : container.getCacheManager().getOrderForKey(key);
+  //}
+
+  @NonNull final PlaybackInfo getPlaybackInfo(int position) {
+    PlaybackInfo info = hotCache != null ? hotCache.get(position) : null;
+    if (info == SCRAP) {  // has hot cache, but was SCRAP.
+      info = container.playerInitializer.initPlaybackInfo(position);
+    }
+
+    Object key = getKey(position);
+    info = info != null ? info : (key != null ? coldCache.get(key) : null);
+    if (info == null) info = container.playerInitializer.initPlaybackInfo(position);
+    return info;
+  }
+
+  // Call by Container#savePlaybackInfo and that method is called right before any pausing.
+  final void savePlaybackInfo(int position, @NonNull PlaybackInfo playbackInfo) {
+    ToroUtil.checkNotNull(playbackInfo);
+    if (hotCache != null) hotCache.put(position, playbackInfo);
+    Object key = getKey(position);
+    if (key != null) coldCache.put(key, playbackInfo);
+  }
+
+  @NonNull SparseArray<PlaybackInfo> saveStates() {
+    SparseArray<PlaybackInfo> states = new SparseArray<>();
+    if (container.getCacheManager() != null) {
+      for (Map.Entry<Integer, Object> entry : coldKeyToOrderMap.entrySet()) {
+        states.put(entry.getKey(), coldCache.get(entry.getValue()));
+      }
+    } else if (hotCache != null) {
+      for (Map.Entry<Integer, PlaybackInfo> entry : hotCache.entrySet()) {
+        states.put(entry.getKey(), entry.getValue());
+      }
+    }
+    return states;
+  }
+
+  void restoreStates(@Nullable SparseArray<?> savedStates) {
+    int cacheSize;
+    if (savedStates != null && (cacheSize = savedStates.size()) > 0) {
+      for (int i = 0; i < cacheSize; i++) {
+        int order = savedStates.keyAt(i);
+        Object key = getKey(order);
+        coldKeyToOrderMap.put(order, key);
+        PlaybackInfo playbackInfo = (PlaybackInfo) savedStates.get(order);
+        if (playbackInfo != null) this.savePlaybackInfo(order, playbackInfo);
+      }
+    }
+  }
+
+  final void clearCache() {
+    coldCache.clear();
+    if (hotCache != null) hotCache.clear();
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PlayerManager.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PlayerManager.java
new file mode 100644
index 00000000..b083a363
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PlayerManager.java
@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2017 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.widget;
+
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Message;
+
+import androidx.annotation.NonNull;
+import androidx.collection.ArraySet;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.PlayerDispatcher;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+
+/**
+ * Manage the collection of {@link ToroPlayer}s for a specific {@link Container}.
+ *
+ * Task: collect all Players in which "{@link Common#allowsToPlay(ToroPlayer)}" returns true, then
+ * initialize them.
+ *
+ * @author eneim | 5/31/17.
+ */
+@SuppressWarnings({ "unused", "UnusedReturnValue", "StatementWithEmptyBody" }) //
+final class PlayerManager implements Handler.Callback {
+
+  private static final String TAG = "ToroLib:Manager";
+  private Handler handler;
+
+  // Make sure each ToroPlayer will present only once in this Manager.
+  private final Set<ToroPlayer> players = new ArraySet<>();
+
+  boolean attachPlayer(@NonNull ToroPlayer player) {
+    return players.add(player);
+  }
+
+  boolean detachPlayer(@NonNull ToroPlayer player) {
+    if (handler != null) handler.removeCallbacksAndMessages(player);
+    return players.remove(player);
+  }
+
+  boolean manages(@NonNull ToroPlayer player) {
+    return players.contains(player);
+  }
+
+  /**
+   * Return a "Copy" of the collection of players this manager is managing.
+   *
+   * @return a non null collection of Players those a managed.
+   */
+  @NonNull List<ToroPlayer> getPlayers() {
+    return new ArrayList<>(this.players);
+  }
+
+  void initialize(@NonNull ToroPlayer player, Container container) {
+    player.initialize(container, container.getPlaybackInfo(player.getPlayerOrder()));
+  }
+
+  // 2018.07.02 Directly pass PlayerDispatcher so that we can easily expand the ability in the future.
+  void play(@NonNull ToroPlayer player, PlayerDispatcher dispatcher) {
+    this.play(player, dispatcher.getDelayToPlay(player));
+  }
+
+  private void play(@NonNull ToroPlayer player, int delay) {
+    if (delay < PlayerDispatcher.DELAY_INFINITE) throw new IllegalArgumentException("Too negative");
+    if (handler == null) return;  // equals to that this is not attached yet.
+    handler.removeMessages(MSG_PLAY, player); // remove undone msg for this player
+    if (delay == PlayerDispatcher.DELAY_INFINITE) {
+      // do nothing
+    } else if (delay == PlayerDispatcher.DELAY_NONE) {
+      player.play();
+    } else {
+      handler.sendMessageDelayed(handler.obtainMessage(MSG_PLAY, player), delay);
+    }
+  }
+
+  void pause(@NonNull ToroPlayer player) {
+    // remove all msg sent for the player
+    if (handler != null) handler.removeCallbacksAndMessages(player);
+    player.pause();
+  }
+
+  // return false if this manager could not release the player.
+  // normally when this manager doesn't manage the player.
+  boolean release(@NonNull ToroPlayer player) {
+    if (handler != null) handler.removeCallbacksAndMessages(null);
+    if (manages(player)) {
+      player.release();
+      return true;
+    } else {
+      return false;
+    }
+  }
+
+  void recycle(ToroPlayer player) {
+    if (handler != null) handler.removeCallbacksAndMessages(player);
+  }
+
+  void clear() {
+    if (handler != null) handler.removeCallbacksAndMessages(null);
+    this.players.clear();
+  }
+
+  void deferPlaybacks() {
+    if (handler != null) handler.removeMessages(MSG_PLAY);
+  }
+
+  void onAttach() {
+    // do nothing
+    if (handler == null) handler = new Handler(Looper.getMainLooper(), this);
+  }
+
+  void onDetach() {
+    if (handler != null) {
+      handler.removeCallbacksAndMessages(null);
+      handler = null;
+    }
+  }
+
+  @SuppressWarnings("WeakerAccess") static final int MSG_PLAY = 100;
+
+  @Override public boolean handleMessage(Message msg) {
+    if (msg.what == MSG_PLAY && msg.obj instanceof ToroPlayer) {
+      ToroPlayer player = (ToroPlayer) msg.obj;
+      player.play();
+    }
+    return true;
+  }
+}
diff --git a/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PressablePlayerSelector.java b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PressablePlayerSelector.java
new file mode 100644
index 00000000..b72d9cd3
--- /dev/null
+++ b/app/src/main/java/ml/docilealligator/infinityforreddit/videoautoplay/widget/PressablePlayerSelector.java
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2018 Nam Nguyen, nam@ene.im
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ml.docilealligator.infinityforreddit.videoautoplay.widget;
+
+import static androidx.recyclerview.widget.RecyclerView.NO_POSITION;
+import static java.util.Collections.singletonList;
+
+import static ml.docilealligator.infinityforreddit.videoautoplay.widget.Common.allowsToPlay;
+import static ml.docilealligator.infinityforreddit.videoautoplay.widget.Common.findFirst;
+
+import android.view.View;
+import android.view.View.OnLongClickListener;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+import java.lang.ref.WeakReference;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import ml.docilealligator.infinityforreddit.videoautoplay.PlayerSelector;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroPlayer;
+import ml.docilealligator.infinityforreddit.videoautoplay.ToroUtil;
+import ml.docilealligator.infinityforreddit.videoautoplay.annotations.Beta;
+
+/**
+ * @author eneim (2018/08/17).
+ *
+ * A 'Press to Play' {@link PlayerSelector}.
+ *
+ * This is a {@link OnLongClickListener} that co-operates with {@link Container} to selectively
+ * trigger the playback. The common usecase is to allow user to long click on a {@link ToroPlayer}
+ * to trigger its playback. In that case, we should set that {@link ToroPlayer} to highest priority
+ * among the candidates, and also to clear its priority when user scroll it out of the playable region.
+ *
+ * This class also have a {@link #toPause} field to handle the case where User want to specifically
+ * pause a {@link ToroPlayer}. This selection will also be cleared with the same rules of toPlay.
+ * @since 3.6.0.2802
+ */
+@SuppressWarnings("WeakerAccess") @Beta //
+public class PressablePlayerSelector implements PlayerSelector, OnLongClickListener {
+
+  protected final WeakReference<Container> weakContainer;
+  protected final PlayerSelector delegate;
+  protected final AtomicInteger toPlay = new AtomicInteger(NO_POSITION);
+  protected final AtomicInteger toPause = new AtomicInteger(NO_POSITION);
+
+  final Common.Filter<ToroPlayer> filterToPlay = new Common.Filter<ToroPlayer>() {
+    @Override public boolean accept(ToroPlayer target) {
+      return target.getPlayerOrder() == toPlay.get();
+    }
+  };
+
+  final Common.Filter<ToroPlayer> filterToPause = new Common.Filter<ToroPlayer>() {
+    @Override public boolean accept(ToroPlayer target) {
+      return target.getPlayerOrder() == toPause.get();
+    }
+  };
+
+  public PressablePlayerSelector(Container container) {
+    this(container, DEFAULT);
+  }
+
+  public PressablePlayerSelector(Container container, PlayerSelector delegate) {
+    this(new WeakReference<>(ToroUtil.checkNotNull(container)), ToroUtil.checkNotNull(delegate));
+  }
+
+  PressablePlayerSelector(WeakReference<Container> container, PlayerSelector delegate) {
+    this.weakContainer = container;
+    this.delegate = ToroUtil.checkNotNull(delegate);
+  }
+
+  @Override public boolean onLongClick(View v) {
+    Container container = weakContainer.get();
+    if (container == null) return false;  // fail fast
+
+    toPause.set(NO_POSITION); // long click will always mean to 'press to play'.
+
+    RecyclerView.ViewHolder viewHolder = container.findContainingViewHolder(v);
+    boolean handled = viewHolder instanceof ToroPlayer;
+    if (handled) handled = allowsToPlay((ToroPlayer) viewHolder);
+
+    int position = handled ? viewHolder.getAdapterPosition() : NO_POSITION;
+    if (handled) handled = position != toPlay.getAndSet(position);
+
+    if (handled) container.onScrollStateChanged(RecyclerView.SCROLL_STATE_IDLE);
+    return handled;
+  }
+
+  @Override @NonNull public Collection<ToroPlayer> select(@NonNull Container container,
+      @NonNull List<ToroPlayer> items) {
+    // Make sure client doesn't use this instance to wrong Container.
+    if (container != this.weakContainer.get()) return new ArrayList<>();
+
+    // If there is a request to pause, we need to prioritize that first.
+    ToroPlayer toPauseCandidate = null;
+    if (toPause.get() >= 0) {
+      toPauseCandidate = findFirst(items, filterToPause);
+      if (toPauseCandidate == null) {
+        // the order to pause doesn't present in candidate, we clear the selection.
+        toPause.set(NO_POSITION); // remove the paused one.
+      }
+    }
+
+    if (toPlay.get() >= 0) {
+      ToroPlayer toPlayCandidate = findFirst(items, filterToPlay);
+      if (toPlayCandidate != null) {
+        if (allowsToPlay(toPlayCandidate)) {
+          return singletonList(toPlayCandidate);
+        }
+      }
+    }
+    // In the list of candidates, selected item no longer presents or is not allowed to play,
+    // we should reset the selection.
+    toPlay.set(NO_POSITION);
+    // Wrap by an ArrayList to make it modifiable.
+    Collection<ToroPlayer> selected = new ArrayList<>(delegate.select(container, items));
+    if (toPauseCandidate != null) selected.remove(toPauseCandidate);
+    return selected;
+  }
+
+  @Override @NonNull public PlayerSelector reverse() {
+    return new PressablePlayerSelector(this.weakContainer, delegate.reverse());
+  }
+
+  public boolean toPlay(int position) {
+    if (toPause.get() == position) toPause.set(NO_POSITION);
+    Container container = weakContainer.get();
+    if (container == null) return false;
+    if (position != toPlay.getAndSet(position)) {
+      container.onScrollStateChanged(RecyclerView.SCROLL_STATE_IDLE);
+      return true;
+    }
+
+    return false;
+  }
+
+  public void toPause(int position) {
+    toPlay.set(NO_POSITION);
+    toPause.set(position);
+  }
+}