From 80c5e00b18e6675f206c4734811ae9c46f5389e0 Mon Sep 17 00:00:00 2001
From: bachinger <bachinger@google.com>
Date: Fri, 29 Oct 2021 12:13:32 +0100
Subject: [PATCH] Defer setting defaults for rendition reports until playlist
 is parsed

This makes sure that #EXT-X-RENDITION-REPORT tags can be placed before
the list of segments/parts as well. We were previously assuming that
these come at the end, which naturally would make sense and is done like
this in all examples, but it is not explicitly defined by the spec.

Issue: google/ExoPlayer#9592
PiperOrigin-RevId: 406329684
---
 .../hls/playlist/HlsPlaylistParser.java       |  34 +++--
 .../playlist/HlsMediaPlaylistParserTest.java  | 116 +++++++++++++++++-
 2 files changed, 135 insertions(+), 15 deletions(-)

diff --git a/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/playlist/HlsPlaylistParser.java b/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/playlist/HlsPlaylistParser.java
index c740eac6cd..30cce581af 100644
--- a/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/playlist/HlsPlaylistParser.java
+++ b/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/playlist/HlsPlaylistParser.java
@@ -647,7 +647,7 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
     List<Segment> segments = new ArrayList<>();
     List<Part> trailingParts = new ArrayList<>();
     @Nullable Part preloadPart = null;
-    Map<Uri, RenditionReport> renditionReports = new HashMap<>();
+    List<RenditionReport> renditionReports = new ArrayList<>();
     List<String> tags = new ArrayList<>();
 
     long segmentDurationUs = 0;
@@ -856,17 +856,11 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
       } else if (line.equals(TAG_ENDLIST)) {
         hasEndTag = true;
       } else if (line.startsWith(TAG_RENDITION_REPORT)) {
-        long defaultValue = mediaSequence + segments.size() - (trailingParts.isEmpty() ? 1 : 0);
-        long lastMediaSequence = parseOptionalLongAttr(line, REGEX_LAST_MSN, defaultValue);
-        List<Part> lastParts =
-            trailingParts.isEmpty() ? Iterables.getLast(segments).parts : trailingParts;
-        int defaultPartIndex =
-            partTargetDurationUs != C.TIME_UNSET ? lastParts.size() - 1 : C.INDEX_UNSET;
-        int lastPartIndex = parseOptionalIntAttr(line, REGEX_LAST_PART, defaultPartIndex);
+        long lastMediaSequence = parseOptionalLongAttr(line, REGEX_LAST_MSN, C.INDEX_UNSET);
+        int lastPartIndex = parseOptionalIntAttr(line, REGEX_LAST_PART, C.INDEX_UNSET);
         String uri = parseStringAttr(line, REGEX_URI, variableDefinitions);
         Uri playlistUri = Uri.parse(UriUtil.resolve(baseUri, uri));
-        renditionReports.put(
-            playlistUri, new RenditionReport(playlistUri, lastMediaSequence, lastPartIndex));
+        renditionReports.add(new RenditionReport(playlistUri, lastMediaSequence, lastPartIndex));
       } else if (line.startsWith(TAG_PRELOAD_HINT)) {
         if (preloadPart != null) {
           continue;
@@ -1024,6 +1018,24 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
       }
     }
 
+    Map<Uri, RenditionReport> renditionReportMap = new HashMap<>();
+    for (int i = 0; i < renditionReports.size(); i++) {
+      RenditionReport renditionReport = renditionReports.get(i);
+      long lastMediaSequence = renditionReport.lastMediaSequence;
+      if (lastMediaSequence == C.INDEX_UNSET) {
+        lastMediaSequence = mediaSequence + segments.size() - (trailingParts.isEmpty() ? 1 : 0);
+      }
+      int lastPartIndex = renditionReport.lastPartIndex;
+      if (lastPartIndex == C.INDEX_UNSET && partTargetDurationUs != C.TIME_UNSET) {
+        List<Part> lastParts =
+            trailingParts.isEmpty() ? Iterables.getLast(segments).parts : trailingParts;
+        lastPartIndex = lastParts.size() - 1;
+      }
+      renditionReportMap.put(
+          renditionReport.playlistUri,
+          new RenditionReport(renditionReport.playlistUri, lastMediaSequence, lastPartIndex));
+    }
+
     if (preloadPart != null) {
       trailingParts.add(preloadPart);
     }
@@ -1048,7 +1060,7 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
         segments,
         trailingParts,
         serverControl,
-        renditionReports);
+        renditionReportMap);
   }
 
   private static DrmInitData getPlaylistProtectionSchemes(
diff --git a/libraries/exoplayer_hls/src/test/java/androidx/media3/exoplayer/hls/playlist/HlsMediaPlaylistParserTest.java b/libraries/exoplayer_hls/src/test/java/androidx/media3/exoplayer/hls/playlist/HlsMediaPlaylistParserTest.java
index 045e29430f..6999617a22 100644
--- a/libraries/exoplayer_hls/src/test/java/androidx/media3/exoplayer/hls/playlist/HlsMediaPlaylistParserTest.java
+++ b/libraries/exoplayer_hls/src/test/java/androidx/media3/exoplayer/hls/playlist/HlsMediaPlaylistParserTest.java
@@ -903,6 +903,114 @@ public class HlsMediaPlaylistParserTest {
     assertThat(report0.lastPartIndex).isEqualTo(2);
   }
 
+  @Test
+  public void
+      parseMediaPlaylist_withRenditionReportBeforeSegmentsWithoutPartTargetDurationWithoutLastMsn_sameLastMsnAsCurrentPlaylist()
+          throws IOException {
+    Uri playlistUri = Uri.parse("https://example.com/test.m3u8");
+    String playlistString =
+        "#EXTM3U\n"
+            + "#EXT-X-TARGETDURATION:4\n"
+            + "#EXT-X-VERSION:6\n"
+            + "#EXT-X-MEDIA-SEQUENCE:266\n"
+            + "#EXT-X-RENDITION-REPORT:URI=\"/rendition0.m3u8\"\n"
+            + "#EXTINF:4.00000,\n"
+            + "fileSequence266.mp4\n";
+    InputStream inputStream = new ByteArrayInputStream(Util.getUtf8Bytes(playlistString));
+
+    HlsMediaPlaylist playlist =
+        (HlsMediaPlaylist) new HlsPlaylistParser().parse(playlistUri, inputStream);
+
+    assertThat(playlist.renditionReports).hasSize(1);
+    HlsMediaPlaylist.RenditionReport report =
+        playlist.renditionReports.get(Uri.parse("https://example.com/rendition0.m3u8"));
+    assertThat(report.lastMediaSequence).isEqualTo(266);
+    assertThat(report.lastPartIndex).isEqualTo(C.INDEX_UNSET);
+  }
+
+  @Test
+  public void
+      parseMediaPlaylist_withRenditionReportBeforeSegementsDefaultMsn_sameMsnAsCurrentPlaylist()
+          throws IOException {
+    Uri playlistUri = Uri.parse("https://example.com/test.m3u8");
+    String playlistString =
+        "#EXTM3U\n"
+            + "#EXT-X-TARGETDURATION:4\n"
+            + "#EXT-X-PART-INF:PART-TARGET=1\n"
+            + "#EXT-X-VERSION:6\n"
+            + "#EXT-X-MEDIA-SEQUENCE:266\n"
+            + "#EXT-X-RENDITION-REPORT:URI=\"/rendition0.m3u8\",LAST-PART=2\n"
+            + "#EXTINF:4.00000,\n"
+            + "fileSequence266.mp4\n"
+            + "#EXT-X-PART:DURATION=2.00000,URI=\"part267.0.ts\"\n";
+    InputStream inputStream = new ByteArrayInputStream(Util.getUtf8Bytes(playlistString));
+
+    HlsMediaPlaylist playlist =
+        (HlsMediaPlaylist) new HlsPlaylistParser().parse(playlistUri, inputStream);
+
+    assertThat(playlist.renditionReports).hasSize(1);
+    HlsMediaPlaylist.RenditionReport report =
+        playlist.renditionReports.get(Uri.parse("https://example.com/rendition0.m3u8"));
+    assertThat(report.lastMediaSequence).isEqualTo(267);
+    assertThat(report.lastPartIndex).isEqualTo(2);
+  }
+
+  @Test
+  public void
+      parseMediaPlaylist_withRenditionReportBeforeSegementsDefaultLastPart_sameLastPartIndexAsCurrentPlaylist()
+          throws IOException {
+    Uri playlistUri = Uri.parse("https://example.com/test.m3u8");
+    String playlistString =
+        "#EXTM3U\n"
+            + "#EXT-X-TARGETDURATION:4\n"
+            + "#EXT-X-PART-INF:PART-TARGET=1\n"
+            + "#EXT-X-VERSION:6\n"
+            + "#EXT-X-MEDIA-SEQUENCE:266\n"
+            + "#EXT-X-RENDITION-REPORT:URI=\"/rendition0.m3u8\",LAST-MSN=267\n"
+            + "#EXTINF:4.00000,\n"
+            + "fileSequence266.mp4\n"
+            + "#EXT-X-PART:DURATION=2.00000,URI=\"part267.0.ts\"\n"
+            + "#EXT-X-PART:DURATION=2.00000,URI=\"part267.1.ts\"\n";
+    InputStream inputStream = new ByteArrayInputStream(Util.getUtf8Bytes(playlistString));
+
+    HlsMediaPlaylist playlist =
+        (HlsMediaPlaylist) new HlsPlaylistParser().parse(playlistUri, inputStream);
+
+    assertThat(playlist.renditionReports).hasSize(1);
+    HlsMediaPlaylist.RenditionReport report =
+        playlist.renditionReports.get(Uri.parse("https://example.com/rendition0.m3u8"));
+    assertThat(report.lastMediaSequence).isEqualTo(267);
+    assertThat(report.lastPartIndex).isEqualTo(1);
+  }
+
+  @Test
+  public void
+      parseMediaPlaylist_withRenditionReportBeforeSegements_sameMsnAndLastPartIndexAsCurrentPlaylist()
+          throws IOException {
+    Uri playlistUri = Uri.parse("https://example.com/test.m3u8");
+    String playlistString =
+        "#EXTM3U\n"
+            + "#EXT-X-TARGETDURATION:4\n"
+            + "#EXT-X-PART-INF:PART-TARGET=1\n"
+            + "#EXT-X-VERSION:6\n"
+            + "#EXT-X-MEDIA-SEQUENCE:266\n"
+            + "#EXT-X-RENDITION-REPORT:URI=\"/rendition0.m3u8\"\n"
+            + "#EXTINF:4.00000,\n"
+            + "fileSequence266.mp4\n"
+            + "#EXT-X-PART:DURATION=2.00000,URI=\"part267.0.ts\"\n"
+            + "#EXT-X-PART:DURATION=2.00000,URI=\"part267.1.ts\"\n";
+    InputStream inputStream = new ByteArrayInputStream(Util.getUtf8Bytes(playlistString));
+
+    HlsMediaPlaylist playlist =
+        (HlsMediaPlaylist) new HlsPlaylistParser().parse(playlistUri, inputStream);
+
+    assertThat(playlist.renditionReports).hasSize(1);
+    HlsMediaPlaylist.RenditionReport report =
+        playlist.renditionReports.get(Uri.parse("https://example.com/rendition0.m3u8"));
+    assertThat(report.lastMediaSequence).isEqualTo(267);
+    assertThat(report.lastPartIndex).isEqualTo(1);
+  }
+
   @Test
   public void
       parseMediaPlaylist_withRenditionReportLowLatencyWithoutLastPartIndex_sameLastPartIndexAsCurrentPlaylist()
@@ -917,7 +1025,7 @@ public class HlsMediaPlaylistParserTest {
             + "#EXTINF:4.00000,\n"
             + "fileSequence266.mp4\n"
             + "#EXT-X-PART:DURATION=2.00000,URI=\"part267.0.ts\"\n"
-            + "#EXT-X-RENDITION-REPORT:URI=\"/rendition0.m3u8\",LAST-MSN=100\n";
+            + "#EXT-X-RENDITION-REPORT:URI=\"/rendition0.m3u8\",LAST-MSN=267\n";
     InputStream inputStream = new ByteArrayInputStream(Util.getUtf8Bytes(playlistString));
 
     HlsMediaPlaylist playlist =
@@ -926,7 +1034,7 @@ public class HlsMediaPlaylistParserTest {
     assertThat(playlist.renditionReports).hasSize(1);
     HlsMediaPlaylist.RenditionReport report0 =
         playlist.renditionReports.get(Uri.parse("https://example.com/rendition0.m3u8"));
-    assertThat(report0.lastMediaSequence).isEqualTo(100);
+    assertThat(report0.lastMediaSequence).isEqualTo(267);
     assertThat(report0.lastPartIndex).isEqualTo(0);
   }
 
@@ -945,7 +1053,7 @@ public class HlsMediaPlaylistParserTest {
             + "fileSequence266.mp4\n"
             + "#EXT-X-PART:DURATION=2.00000,URI=\"part267.0.ts\"\n"
             + "#EXT-X-PRELOAD-HINT:TYPE=PART,URI=\"filePart267.1.ts\"\n"
-            + "#EXT-X-RENDITION-REPORT:URI=\"/rendition0.m3u8\",LAST-MSN=100\n";
+            + "#EXT-X-RENDITION-REPORT:URI=\"/rendition0.m3u8\",LAST-MSN=267\n";
     InputStream inputStream = new ByteArrayInputStream(Util.getUtf8Bytes(playlistString));
 
     HlsMediaPlaylist playlist =
@@ -955,7 +1063,7 @@ public class HlsMediaPlaylistParserTest {
     assertThat(playlist.renditionReports).hasSize(1);
     HlsMediaPlaylist.RenditionReport report0 =
         playlist.renditionReports.get(Uri.parse("https://example.com/rendition0.m3u8"));
-    assertThat(report0.lastMediaSequence).isEqualTo(100);
+    assertThat(report0.lastMediaSequence).isEqualTo(267);
     assertThat(report0.lastPartIndex).isEqualTo(0);
   }