Avoid recalculation of whether a MediaPeriod is part of a SSAI stream

We can instead just save this information in MediaPeriodInfo, similar
to how we store whether the MediaPeriod is last in the timeline etc.

PiperOrigin-RevId: 374835918

library/core/src/main/java/com/google/android/exoplayer2/MediaPeriodInfo.java

@@ -18,6 +18,7 @@ package com.google.android.exoplayer2;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.source.MediaPeriod;
 import com.google.android.exoplayer2.source.MediaSource.MediaPeriodId;
+import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Util;
 
 /** Stores the information required to load and play a {@link MediaPeriod}. */
@@ -49,6 +50,12 @@ import com.google.android.exoplayer2.util.Util;
    */
   public final long durationUs;
   /**
+   * Whether this media period is followed by a transition to another media period of the same
+   * server-side inserted ad stream. If true, {@link #isLastInTimelinePeriod}, {@link
+   * #isLastInTimelineWindow} and {@link #isFinal} will all be false.
+   */
+  public final boolean isFollowedByTransitionToSameStream;
+  /**
    * Whether this is the last media period in its timeline period (e.g., a postroll ad, or a media
    * period corresponding to a timeline period without ads).
    */
@@ -67,14 +74,21 @@ import com.google.android.exoplayer2.util.Util;
       long requestedContentPositionUs,
       long endPositionUs,
       long durationUs,
+      boolean isFollowedByTransitionToSameStream,
       boolean isLastInTimelinePeriod,
       boolean isLastInTimelineWindow,
       boolean isFinal) {
+    Assertions.checkArgument(!isFinal || isLastInTimelinePeriod);
+    Assertions.checkArgument(!isLastInTimelineWindow || isLastInTimelinePeriod);
+    Assertions.checkArgument(
+        !isFollowedByTransitionToSameStream
+            || (!isLastInTimelinePeriod && !isLastInTimelineWindow && !isFinal));
     this.id = id;
     this.startPositionUs = startPositionUs;
     this.requestedContentPositionUs = requestedContentPositionUs;
     this.endPositionUs = endPositionUs;
     this.durationUs = durationUs;
+    this.isFollowedByTransitionToSameStream = isFollowedByTransitionToSameStream;
     this.isLastInTimelinePeriod = isLastInTimelinePeriod;
     this.isLastInTimelineWindow = isLastInTimelineWindow;
     this.isFinal = isFinal;
@@ -93,6 +107,7 @@ import com.google.android.exoplayer2.util.Util;
             requestedContentPositionUs,
             endPositionUs,
             durationUs,
+            isFollowedByTransitionToSameStream,
             isLastInTimelinePeriod,
             isLastInTimelineWindow,
             isFinal);
@@ -111,6 +126,7 @@ import com.google.android.exoplayer2.util.Util;
             requestedContentPositionUs,
             endPositionUs,
             durationUs,
+            isFollowedByTransitionToSameStream,
             isLastInTimelinePeriod,
             isLastInTimelineWindow,
             isFinal);
@@ -129,6 +145,7 @@ import com.google.android.exoplayer2.util.Util;
         && requestedContentPositionUs == that.requestedContentPositionUs
         && endPositionUs == that.endPositionUs
         && durationUs == that.durationUs
+        && isFollowedByTransitionToSameStream == that.isFollowedByTransitionToSameStream
         && isLastInTimelinePeriod == that.isLastInTimelinePeriod
         && isLastInTimelineWindow == that.isLastInTimelineWindow
         && isFinal == that.isFinal
@@ -143,6 +160,7 @@ import com.google.android.exoplayer2.util.Util;
     result = 31 * result + (int) requestedContentPositionUs;
     result = 31 * result + (int) endPositionUs;
     result = 31 * result + (int) durationUs;
+    result = 31 * result + (isFollowedByTransitionToSameStream ? 1 : 0);
     result = 31 * result + (isLastInTimelinePeriod ? 1 : 0);
     result = 31 * result + (isLastInTimelineWindow ? 1 : 0);
     result = 31 * result + (isFinal ? 1 : 0);

library/core/src/main/java/com/google/android/exoplayer2/MediaPeriodQueue.java

@@ -358,7 +358,7 @@ import com.google.common.collect.ImmutableList;
                 : periodHolder.toRendererTime(newPeriodInfo.durationUs);
         boolean isReadingAndReadBeyondNewDuration =
             periodHolder == reading
-                && !isUsingSameStreamForNextMediaPeriod(timeline, periodHolder.info.id)
+                && !periodHolder.info.isFollowedByTransitionToSameStream
                 && (maxRendererReadPositionUs == C.TIME_END_OF_SOURCE
                     || maxRendererReadPositionUs >= newDurationInRendererTime);
         boolean readingPeriodRemoved = removeAfter(periodHolder);
@@ -396,12 +396,18 @@ import com.google.common.collect.ImmutableList;
             : (endPositionUs == C.TIME_UNSET || endPositionUs == C.TIME_END_OF_SOURCE
                 ? period.getDurationUs()
                 : endPositionUs);
+    boolean isFollowedByTransitionToSameStream =
+        id.isAd()
+            ? period.isServerSideInsertedAdGroup(id.adGroupIndex)
+            : (id.nextAdGroupIndex != C.INDEX_UNSET
+                && period.isServerSideInsertedAdGroup(id.nextAdGroupIndex));
     return new MediaPeriodInfo(
         id,
         info.startPositionUs,
         info.requestedContentPositionUs,
         endPositionUs,
         durationUs,
+        isFollowedByTransitionToSameStream,
         isLastInPeriod,
         isLastInWindow,
         isLastInTimeline);
@@ -778,6 +784,8 @@ import com.google.common.collect.ImmutableList;
         adIndexInAdGroup == period.getFirstAdIndexToPlay(adGroupIndex)
             ? period.getAdResumePositionUs()
             : 0;
+    boolean isFollowedByTransitionToSameStream =
+        period.isServerSideInsertedAdGroup(id.adGroupIndex);
     if (durationUs != C.TIME_UNSET && startPositionUs >= durationUs) {
       // Ensure start position doesn't exceed duration.
       startPositionUs = max(0, durationUs - 1);
@@ -788,6 +796,7 @@ import com.google.common.collect.ImmutableList;
         contentPositionUs,
         /* endPositionUs= */ C.TIME_UNSET,
         durationUs,
+        isFollowedByTransitionToSameStream,
         /* isLastInTimelinePeriod= */ false,
         /* isLastInTimelineWindow= */ false,
         /* isFinal= */ false);
@@ -805,6 +814,8 @@ import com.google.common.collect.ImmutableList;
     boolean isLastInPeriod = isLastInPeriod(id);
     boolean isLastInWindow = isLastInWindow(timeline, id);
     boolean isLastInTimeline = isLastInTimeline(timeline, id, isLastInPeriod);
+    boolean isFollowedByTransitionToSameStream =
+        nextAdGroupIndex != C.INDEX_UNSET && period.isServerSideInsertedAdGroup(nextAdGroupIndex);
     long endPositionUs =
         nextAdGroupIndex != C.INDEX_UNSET
             ? period.getAdGroupTimeUs(nextAdGroupIndex)
@@ -823,6 +834,7 @@ import com.google.common.collect.ImmutableList;
         requestedContentPositionUs,
         endPositionUs,
         durationUs,
+        isFollowedByTransitionToSameStream,
         isLastInPeriod,
         isLastInWindow,
         isLastInTimeline);
@@ -859,20 +871,4 @@ import com.google.common.collect.ImmutableList;
     }
     return startPositionUs + period.getContentResumeOffsetUs(adGroupIndex);
   }
-
-  private boolean isUsingSameStreamForNextMediaPeriod(
-      Timeline timeline, MediaPeriodId mediaPeriodId) {
-    // Server-side inserted ads or content after them will use the same underlying stream.
-    if (mediaPeriodId.isAd()) {
-      return timeline
-          .getPeriodByUid(mediaPeriodId.periodUid, period)
-          .isServerSideInsertedAdGroup(mediaPeriodId.adGroupIndex);
-    } else if (mediaPeriodId.nextAdGroupIndex == C.INDEX_UNSET) {
-      return false;
-    } else {
-      return timeline
-          .getPeriodByUid(mediaPeriodId.periodUid, period)
-          .isServerSideInsertedAdGroup(mediaPeriodId.nextAdGroupIndex);
-    }
-  }
 }