Infer track URI from context

Author: devgianlu

lib/src/main/java/xyz/gianlu/librespot/common/ProtoUtils.java

@@ -12,6 +12,8 @@
 import com.spotify.context.ContextPlayerOptionsOuterClass;
 import com.spotify.metadata.Metadata;
 import com.spotify.playlist4.Playlist4ApiProto;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -28,6 +30,8 @@
  * @author Gianlu
  */
 public final class ProtoUtils {
+    private static final Logger LOGGER = LogManager.getLogger(ProtoUtils.class);
+
     private ProtoUtils() {
     }
 
@@ -61,11 +65,15 @@ private static JsonObject trackToJson(@NotNull Player.ProvidedTrack track) {
     }
 
     @NotNull
-    private static JsonObject trackToJson(@NotNull ContextTrack track) {
+    private static JsonObject trackToJson(@NotNull ContextTrack track, String uriPrefix) {
         JsonObject obj = new JsonObject();
-        if (track.hasUri() && !track.getUri().isEmpty()) obj.addProperty("uri", track.getUri());
         if (track.hasUid()) obj.addProperty("uid", track.getUid());
         obj.add("metadata", mapToJson(track.getMetadataMap()));
+        if (track.hasUri() && !track.getUri().isEmpty())
+            obj.addProperty("uri", track.getUri());
+        else if (track.hasGid() && uriPrefix != null)
+            obj.addProperty("uri", uriPrefix + new String(PlayableId.BASE62.encode(track.getGid().toByteArray(), 22)));
+
         return obj;
     }
 
@@ -83,7 +91,7 @@ public static JsonObject craftContextStateCombo(@NotNull Player.PlayerStateOrBui
         page.addProperty("page_url", "");
         page.addProperty("next_page_url", "");
         JsonArray tracksJson = new JsonArray(tracks.size());
-        for (ContextTrack t : tracks) tracksJson.add(trackToJson(t));
+        for (ContextTrack t : tracks) tracksJson.add(trackToJson(t, PlayableId.inferUriPrefix(ps.getContextUri())));
         page.add("tracks", tracksJson);
         page.add("metadata", mapToJson(ps.getPageMetadataMap()));
         pages.add(page);

lib/src/main/java/xyz/gianlu/librespot/metadata/EpisodeId.java

@@ -1,7 +1,6 @@
 package xyz.gianlu.librespot.metadata;
 
 import org.jetbrains.annotations.NotNull;
-import xyz.gianlu.librespot.common.Base62;
 import xyz.gianlu.librespot.common.Utils;
 
 import java.util.regex.Matcher;
@@ -12,7 +11,6 @@
  */
 public final class EpisodeId implements SpotifyId, PlayableId {
     static final Pattern PATTERN = Pattern.compile("spotify:episode:(.{22})");
-    private static final Base62 BASE62 = Base62.createInstanceWithInvertedCharacterSet();
     private final String hexId;
 
     private EpisodeId(@NotNull String hex) {

lib/src/main/java/xyz/gianlu/librespot/metadata/PlayableId.java

@@ -5,6 +5,7 @@
 import com.spotify.metadata.Metadata;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import xyz.gianlu.librespot.common.Base62;
 import xyz.gianlu.librespot.common.Utils;
 
 import java.util.Arrays;
@@ -17,6 +18,8 @@
  * @author Gianlu
  */
 public interface PlayableId {
+    Base62 BASE62 = Base62.createInstanceWithInvertedCharacterSet();
+
     @NotNull
     static PlayableId fromUri(@NotNull String uri) {
         if (!isSupported(uri)) return new UnsupportedId(uri);
@@ -80,6 +83,14 @@ static PlayableId from(@NotNull Metadata.Episode episode) {
         return EpisodeId.fromHex(Utils.bytesToHex(episode.getGid()));
     }
 
+    @NotNull
+    static String inferUriPrefix(@NotNull String contextUri) {
+        if (contextUri.startsWith("spotify:episode:") || contextUri.startsWith("spotify:show:"))
+            return "spotify:episode:";
+        else
+            return "spotify:track:";
+    }
+
     @NotNull
     String toString();
 

lib/src/main/java/xyz/gianlu/librespot/metadata/TrackId.java

@@ -1,7 +1,6 @@
 package xyz.gianlu.librespot.metadata;
 
 import org.jetbrains.annotations.NotNull;
-import xyz.gianlu.librespot.common.Base62;
 import xyz.gianlu.librespot.common.Utils;
 
 import java.util.regex.Matcher;
@@ -12,7 +11,6 @@
  */
 public final class TrackId implements SpotifyId, PlayableId {
     static final Pattern PATTERN = Pattern.compile("spotify:track:(.{22})");
-    private static final Base62 BASE62 = Base62.createInstanceWithInvertedCharacterSet();
     private final String hexId;
 
     private TrackId(@NotNull String hex) {

player/src/main/java/xyz/gianlu/librespot/player/PagesLoader.java

@@ -10,6 +10,7 @@
 import xyz.gianlu.librespot.mercury.MercuryClient;
 import xyz.gianlu.librespot.mercury.MercuryRequests;
 import xyz.gianlu.librespot.mercury.RawMercuryRequest;
+import xyz.gianlu.librespot.metadata.PlayableId;
 
 import java.io.IOException;
 import java.io.InputStreamReader;
@@ -46,10 +47,20 @@ public static PagesLoader from(@NotNull Session session, @NotNull Context contex
         if (pages.isEmpty()) return from(session, context.getUri());
 
         PagesLoader loader = new PagesLoader(session);
-        loader.pages.addAll(pages);
+        loader.putFirstPages(pages, PlayableId.inferUriPrefix(context.getUri()));
         return loader;
     }
 
+    private static void sanitizeTracks(List<ContextTrack> tracks, String uriPrefix) {
+        for (int i = 0; i < tracks.size(); i++) {
+            ContextTrack.Builder builder = tracks.get(i).toBuilder();
+            if (builder.hasUri() || !builder.hasGid()) continue;
+
+            builder.setUri(uriPrefix + new String(PlayableId.BASE62.encode(builder.getGid().toByteArray(), 22)));
+            tracks.set(i, builder.build());
+        }
+    }
+
     @NotNull
     private List<ContextTrack> fetchTracks(@NotNull String url) throws IOException {
         MercuryClient.Response resp = session.mercury().sendSync(RawMercuryRequest.newBuilder()
@@ -123,13 +134,17 @@ boolean nextPage() throws IOException, MercuryClient.MercuryException {
         }
     }
 
-    void putFirstPages(@NotNull List<ContextPage> pages) {
+    void putFirstPages(@NotNull List<ContextPage> pages, String contextUri) {
         if (currentPage != -1 || !this.pages.isEmpty()) throw new IllegalStateException();
-        this.pages.addAll(pages);
+        for (ContextPage page : pages) {
+            sanitizeTracks(page.getTracksList(), contextUri == null ? null : PlayableId.inferUriPrefix(contextUri));
+            this.pages.add(page);
+        }
     }
 
-    void putFirstPage(@NotNull List<ContextTrack> tracks) {
+    void putFirstPage(@NotNull List<ContextTrack> tracks, String contextUri) {
         if (currentPage != -1 || !pages.isEmpty()) throw new IllegalStateException();
+        sanitizeTracks(tracks, contextUri == null ? null : PlayableId.inferUriPrefix(contextUri));
         pages.add(ContextPage.newBuilder().addAllTracks(tracks).build());
     }
 }

player/src/main/java/xyz/gianlu/librespot/player/StateWrapper.java

@@ -442,7 +442,7 @@ String loadContextWithTracks(@NotNull String uri, @NotNull List<ContextTrack> tr
         state.setOptions(ContextPlayerOptions.newBuilder().build());
 
         String sessionId = setContext(uri);
-        pages.putFirstPage(tracks);
+        pages.putFirstPage(tracks, uri);
         tracksKeeper.initializeStart();
         setPosition(0);