1 files changed, 217 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/trackselection/BaseTrackSelection.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/trackselection/BaseTrackSelection.java
new file mode 100644
index 0000000000..d7e94cb561
--- /dev/null
+++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/trackselection/BaseTrackSelection.java
@@ -0,0 +1,217 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * 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 org.mozilla.thirdparty.com.google.android.exoplayer2.trackselection;
+
+import android.os.SystemClock;
+import androidx.annotation.Nullable;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.C;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.Format;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.source.TrackGroup;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.source.chunk.MediaChunk;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Assertions;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Util;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.List;
+
+/**
+ * An abstract base class suitable for most {@link TrackSelection} implementations.
+ */
+public abstract class BaseTrackSelection implements TrackSelection {
+
+  /**
+   * The selected {@link TrackGroup}.
+   */
+  protected final TrackGroup group;
+  /**
+   * The number of selected tracks within the {@link TrackGroup}. Always greater than zero.
+   */
+  protected final int length;
+  /**
+   * The indices of the selected tracks in {@link #group}, in order of decreasing bandwidth.
+   */
+  protected final int[] tracks;
+
+  /**
+   * The {@link Format}s of the selected tracks, in order of decreasing bandwidth.
+   */
+  private final Format[] formats;
+  /**
+   * Selected track blacklist timestamps, in order of decreasing bandwidth.
+   */
+  private final long[] blacklistUntilTimes;
+
+  // Lazily initialized hashcode.
+  private int hashCode;
+
+  /**
+   * @param group The {@link TrackGroup}. Must not be null.
+   * @param tracks The indices of the selected tracks within the {@link TrackGroup}. Must not be
+   *     null or empty. May be in any order.
+   */
+  public BaseTrackSelection(TrackGroup group, int... tracks) {
+    Assertions.checkState(tracks.length > 0);
+    this.group = Assertions.checkNotNull(group);
+    this.length = tracks.length;
+    // Set the formats, sorted in order of decreasing bandwidth.
+    formats = new Format[length];
+    for (int i = 0; i < tracks.length; i++) {
+      formats[i] = group.getFormat(tracks[i]);
+    }
+    Arrays.sort(formats, new DecreasingBandwidthComparator());
+    // Set the format indices in the same order.
+    this.tracks = new int[length];
+    for (int i = 0; i < length; i++) {
+      this.tracks[i] = group.indexOf(formats[i]);
+    }
+    blacklistUntilTimes = new long[length];
+  }
+
+  @Override
+  public void enable() {
+    // Do nothing.
+  }
+
+  @Override
+  public void disable() {
+    // Do nothing.
+  }
+
+  @Override
+  public final TrackGroup getTrackGroup() {
+    return group;
+  }
+
+  @Override
+  public final int length() {
+    return tracks.length;
+  }
+
+  @Override
+  public final Format getFormat(int index) {
+    return formats[index];
+  }
+
+  @Override
+  public final int getIndexInTrackGroup(int index) {
+    return tracks[index];
+  }
+
+  @Override
+  @SuppressWarnings("ReferenceEquality")
+  public final int indexOf(Format format) {
+    for (int i = 0; i < length; i++) {
+      if (formats[i] == format) {
+        return i;
+      }
+    }
+    return C.INDEX_UNSET;
+  }
+
+  @Override
+  public final int indexOf(int indexInTrackGroup) {
+    for (int i = 0; i < length; i++) {
+      if (tracks[i] == indexInTrackGroup) {
+        return i;
+      }
+    }
+    return C.INDEX_UNSET;
+  }
+
+  @Override
+  public final Format getSelectedFormat() {
+    return formats[getSelectedIndex()];
+  }
+
+  @Override
+  public final int getSelectedIndexInTrackGroup() {
+    return tracks[getSelectedIndex()];
+  }
+
+  @Override
+  public void onPlaybackSpeed(float playbackSpeed) {
+    // Do nothing.
+  }
+
+  @Override
+  public int evaluateQueueSize(long playbackPositionUs, List<? extends MediaChunk> queue) {
+    return queue.size();
+  }
+
+  @Override
+  public final boolean blacklist(int index, long blacklistDurationMs) {
+    long nowMs = SystemClock.elapsedRealtime();
+    boolean canBlacklist = isBlacklisted(index, nowMs);
+    for (int i = 0; i < length && !canBlacklist; i++) {
+      canBlacklist = i != index && !isBlacklisted(i, nowMs);
+    }
+    if (!canBlacklist) {
+      return false;
+    }
+    blacklistUntilTimes[index] =
+        Math.max(
+            blacklistUntilTimes[index],
+            Util.addWithOverflowDefault(nowMs, blacklistDurationMs, Long.MAX_VALUE));
+    return true;
+  }
+
+  /**
+   * Returns whether the track at the specified index in the selection is blacklisted.
+   *
+   * @param index The index of the track in the selection.
+   * @param nowMs The current time in the timebase of {@link SystemClock#elapsedRealtime()}.
+   */
+  protected final boolean isBlacklisted(int index, long nowMs) {
+    return blacklistUntilTimes[index] > nowMs;
+  }
+
+  // Object overrides.
+
+  @Override
+  public int hashCode() {
+    if (hashCode == 0) {
+      hashCode = 31 * System.identityHashCode(group) + Arrays.hashCode(tracks);
+    }
+    return hashCode;
+  }
+
+  // Track groups are compared by identity not value, as distinct groups may have the same value.
+  @Override
+  @SuppressWarnings({"ReferenceEquality", "EqualsGetClass"})
+  public boolean equals(@Nullable Object obj) {
+    if (this == obj) {
+      return true;
+    }
+    if (obj == null || getClass() != obj.getClass()) {
+      return false;
+    }
+    BaseTrackSelection other = (BaseTrackSelection) obj;
+    return group == other.group && Arrays.equals(tracks, other.tracks);
+  }
+
+  /**
+   * Sorts {@link Format} objects in order of decreasing bandwidth.
+   */
+  private static final class DecreasingBandwidthComparator implements Comparator<Format> {
+
+    @Override
+    public int compare(Format a, Format b) {
+      return b.bitrate - a.bitrate;
+    }
+
+  }
+
+}