From 15b8da05aa70ae73957c68d00c78528a0ec7deb9 Mon Sep 17 00:00:00 2001
From: Casey Occhialini <1508707+littlespex@users.noreply.github.com>
Date: Tue, 3 Oct 2023 16:37:59 -0700
Subject: [PATCH] fix: seeking in segment timeline returns incorrect index
 (#5716)

Resolves #5664
---
 lib/media/segment_index.js                    |  8 ++--
 .../dash/dash_parser_segment_template_unit.js | 42 +++++++++++++++++++
 2 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/lib/media/segment_index.js b/lib/media/segment_index.js
index 11d575ca6e..832c8a566c 100644
--- a/lib/media/segment_index.js
+++ b/lib/media/segment_index.js
@@ -708,7 +708,7 @@ shaka.media.MetaSegmentIndex = class extends shaka.media.SegmentIndex {
       }
 
       numPassedInEarlierIndexes += index.numEvicted_ +
-        index.references.length;
+        index.getNumReferences();
     }
 
     return null;
@@ -732,9 +732,9 @@ shaka.media.MetaSegmentIndex = class extends shaka.media.SegmentIndex {
         return reference;
       }
 
-      numPassedInEarlierIndexes += index.numEvicted_ +
-        index.references.length;
-      sawSegments = sawSegments || index.references.length != 0;
+      const num = index.getNumReferences();
+      numPassedInEarlierIndexes += index.numEvicted_ + num;
+      sawSegments = sawSegments || num != 0;
     }
 
     return null;
diff --git a/test/dash/dash_parser_segment_template_unit.js b/test/dash/dash_parser_segment_template_unit.js
index b456c7b387..3fa3e83408 100644
--- a/test/dash/dash_parser_segment_template_unit.js
+++ b/test/dash/dash_parser_segment_template_unit.js
@@ -675,6 +675,48 @@ describe('DashParser SegmentTemplate', () => {
         expect(pos).toBe(1);
       });
 
+      it('finds correct position in multiperiod content', async () => {
+        const source = [
+          '<MPD type="static" availabilityStartTime="1970-01-01T00:00:00Z">',
+          '  <Period duration="PT30S">',
+          '    <AdaptationSet mimeType="video/mp4">',
+          '      <Representation bandwidth="500">',
+          '        <BaseURL>http://example.com</BaseURL>',
+          '          <SegmentTemplate startNumber="0"',
+          '            media="$Number$-$Time$-$Bandwidth$.mp4">',
+          '            <SegmentTimeline>',
+          '              <S t="0" d="5" r="6" />',
+          '            </SegmentTimeline>',
+          '          </SegmentTemplate>',
+          '      </Representation>',
+          '    </AdaptationSet>',
+          '  </Period>',
+          '  <Period duration="PT30S">',
+          '    <AdaptationSet mimeType="video/mp4">',
+          '      <Representation bandwidth="500">',
+          '        <BaseURL>http://example.com</BaseURL>',
+          '          <SegmentTemplate startNumber="6"',
+          '            media="$Number$-$Time$-$Bandwidth$.mp4">',
+          '            <SegmentTimeline>',
+          '              <S t="0" d="5" r="6" />',
+          '            </SegmentTimeline>',
+          '          </SegmentTemplate>',
+          '      </Representation>',
+          '    </AdaptationSet>',
+          '  </Period>',
+          '</MPD>',
+        ].join('\n');
+
+        fakeNetEngine.setResponseText('dummy://foo', source);
+        const manifest = await parser.start('dummy://foo', playerInterface);
+        const stream = manifest.variants[0].video;
+        await stream.createSegmentIndex();
+
+        // simulate a seek into the second period
+        const segmentIterator = stream.segmentIndex.getIteratorForTime(42);
+        const ref = segmentIterator.next().value;
+        expect(ref.startTime).toBe(40);
+      });
 
       it('returns null if time === last end time', async () => {
         const info = makeTemplateInfo(makeRanges(0, 2.0, 2));