1 files changed, 236 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/source/MaskingMediaPeriod.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/source/MaskingMediaPeriod.java
new file mode 100644
index 0000000000..4fe7b137b6
--- /dev/null
+++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/source/MaskingMediaPeriod.java
@@ -0,0 +1,236 @@
+/*
+ * Copyright (C) 2017 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.source;
+
+import static org.mozilla.thirdparty.com.google.android.exoplayer2.util.Util.castNonNull;
+
+import androidx.annotation.Nullable;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.C;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.SeekParameters;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.source.MediaSource.MediaPeriodId;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.trackselection.TrackSelection;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.upstream.Allocator;
+import java.io.IOException;
+import org.checkerframework.checker.nullness.compatqual.NullableType;
+
+/**
+ * Media period that wraps a media source and defers calling its {@link
+ * MediaSource#createPeriod(MediaPeriodId, Allocator, long)} method until {@link
+ * #createPeriod(MediaPeriodId)} has been called. This is useful if you need to return a media
+ * period immediately but the media source that should create it is not yet prepared.
+ */
+public final class MaskingMediaPeriod implements MediaPeriod, MediaPeriod.Callback {
+
+  /** Listener for preparation errors. */
+  public interface PrepareErrorListener {
+
+    /**
+     * Called the first time an error occurs while refreshing source info or preparing the period.
+     */
+    void onPrepareError(MediaPeriodId mediaPeriodId, IOException exception);
+  }
+
+  /** The {@link MediaSource} which will create the actual media period. */
+  public final MediaSource mediaSource;
+  /** The {@link MediaPeriodId} used to create the masking media period. */
+  public final MediaPeriodId id;
+
+  private final Allocator allocator;
+
+  @Nullable private MediaPeriod mediaPeriod;
+  @Nullable private Callback callback;
+  private long preparePositionUs;
+  @Nullable private PrepareErrorListener listener;
+  private boolean notifiedPrepareError;
+  private long preparePositionOverrideUs;
+
+  /**
+   * Creates a new masking media period.
+   *
+   * @param mediaSource The media source to wrap.
+   * @param id The identifier used to create the masking media period.
+   * @param allocator The allocator used to create the media period.
+   * @param preparePositionUs The expected start position, in microseconds.
+   */
+  public MaskingMediaPeriod(
+      MediaSource mediaSource, MediaPeriodId id, Allocator allocator, long preparePositionUs) {
+    this.id = id;
+    this.allocator = allocator;
+    this.mediaSource = mediaSource;
+    this.preparePositionUs = preparePositionUs;
+    preparePositionOverrideUs = C.TIME_UNSET;
+  }
+
+  /**
+   * Sets a listener for preparation errors.
+   *
+   * @param listener An listener to be notified of media period preparation errors. If a listener is
+   *     set, {@link #maybeThrowPrepareError()} will not throw but will instead pass the first
+   *     preparation error (if any) to the listener.
+   */
+  public void setPrepareErrorListener(PrepareErrorListener listener) {
+    this.listener = listener;
+  }
+
+  /** Returns the position at which the masking media period was prepared, in microseconds. */
+  public long getPreparePositionUs() {
+    return preparePositionUs;
+  }
+
+  /**
+   * Overrides the default prepare position at which to prepare the media period. This value is only
+   * used if called before {@link #createPeriod(MediaPeriodId)}.
+   *
+   * @param preparePositionUs The default prepare position to use, in microseconds.
+   */
+  public void overridePreparePositionUs(long preparePositionUs) {
+    preparePositionOverrideUs = preparePositionUs;
+  }
+
+  /**
+   * Calls {@link MediaSource#createPeriod(MediaPeriodId, Allocator, long)} on the wrapped source
+   * then prepares it if {@link #prepare(Callback, long)} has been called. Call {@link
+   * #releasePeriod()} to release the period.
+   *
+   * @param id The identifier that should be used to create the media period from the media source.
+   */
+  public void createPeriod(MediaPeriodId id) {
+    long preparePositionUs = getPreparePositionWithOverride(this.preparePositionUs);
+    mediaPeriod = mediaSource.createPeriod(id, allocator, preparePositionUs);
+    if (callback != null) {
+      mediaPeriod.prepare(this, preparePositionUs);
+    }
+  }
+
+  /**
+   * Releases the period.
+   */
+  public void releasePeriod() {
+    if (mediaPeriod != null) {
+      mediaSource.releasePeriod(mediaPeriod);
+    }
+  }
+
+  @Override
+  public void prepare(Callback callback, long preparePositionUs) {
+    this.callback = callback;
+    if (mediaPeriod != null) {
+      mediaPeriod.prepare(this, getPreparePositionWithOverride(this.preparePositionUs));
+    }
+  }
+
+  @Override
+  public void maybeThrowPrepareError() throws IOException {
+    try {
+      if (mediaPeriod != null) {
+        mediaPeriod.maybeThrowPrepareError();
+      } else {
+        mediaSource.maybeThrowSourceInfoRefreshError();
+      }
+    } catch (final IOException e) {
+      if (listener == null) {
+        throw e;
+      }
+      if (!notifiedPrepareError) {
+        notifiedPrepareError = true;
+        listener.onPrepareError(id, e);
+      }
+    }
+  }
+
+  @Override
+  public TrackGroupArray getTrackGroups() {
+    return castNonNull(mediaPeriod).getTrackGroups();
+  }
+
+  @Override
+  public long selectTracks(
+      @NullableType TrackSelection[] selections,
+      boolean[] mayRetainStreamFlags,
+      @NullableType SampleStream[] streams,
+      boolean[] streamResetFlags,
+      long positionUs) {
+    if (preparePositionOverrideUs != C.TIME_UNSET && positionUs == preparePositionUs) {
+      positionUs = preparePositionOverrideUs;
+      preparePositionOverrideUs = C.TIME_UNSET;
+    }
+    return castNonNull(mediaPeriod)
+        .selectTracks(selections, mayRetainStreamFlags, streams, streamResetFlags, positionUs);
+  }
+
+  @Override
+  public void discardBuffer(long positionUs, boolean toKeyframe) {
+    castNonNull(mediaPeriod).discardBuffer(positionUs, toKeyframe);
+  }
+
+  @Override
+  public long readDiscontinuity() {
+    return castNonNull(mediaPeriod).readDiscontinuity();
+  }
+
+  @Override
+  public long getBufferedPositionUs() {
+    return castNonNull(mediaPeriod).getBufferedPositionUs();
+  }
+
+  @Override
+  public long seekToUs(long positionUs) {
+    return castNonNull(mediaPeriod).seekToUs(positionUs);
+  }
+
+  @Override
+  public long getAdjustedSeekPositionUs(long positionUs, SeekParameters seekParameters) {
+    return castNonNull(mediaPeriod).getAdjustedSeekPositionUs(positionUs, seekParameters);
+  }
+
+  @Override
+  public long getNextLoadPositionUs() {
+    return castNonNull(mediaPeriod).getNextLoadPositionUs();
+  }
+
+  @Override
+  public void reevaluateBuffer(long positionUs) {
+    castNonNull(mediaPeriod).reevaluateBuffer(positionUs);
+  }
+
+  @Override
+  public boolean continueLoading(long positionUs) {
+    return mediaPeriod != null && mediaPeriod.continueLoading(positionUs);
+  }
+
+  @Override
+  public boolean isLoading() {
+    return mediaPeriod != null && mediaPeriod.isLoading();
+  }
+
+  @Override
+  public void onContinueLoadingRequested(MediaPeriod source) {
+    castNonNull(callback).onContinueLoadingRequested(this);
+  }
+
+  // MediaPeriod.Callback implementation
+
+  @Override
+  public void onPrepared(MediaPeriod mediaPeriod) {
+    castNonNull(callback).onPrepared(this);
+  }
+
+  private long getPreparePositionWithOverride(long preparePositionUs) {
+    return preparePositionOverrideUs != C.TIME_UNSET
+        ? preparePositionOverrideUs
+        : preparePositionUs;
+  }
+}