Fix HLS encryption method detection

Issue:#4145

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=193494319

RELEASENOTES.md

@@ -66,8 +66,11 @@
     ([#4022][https://github.com/google/ExoPlayer/issues/4022]).
   * Fix handling of 307/308 redirects when making license requests
     ([#4108](https://github.com/google/ExoPlayer/issues/4108)).
-* HLS: Fix playlist loading error propagation when the current selection does
+* HLS:
-  not include all of the playlist's variants.
+  * Fix playlist loading error propagation when the current selection does
+    not include all of the playlist's variants.
+  * Fix SAMPLE-AES-CENC and SAMPLE-AES-CTR EXT-X-KEY methods
+    ([#4145](https://github.com/google/ExoPlayer/issues/4145)).
 * Fix ClearKey decryption error if the key contains a forward slash
   ([#4075](https://github.com/google/ExoPlayer/issues/4075)).
 * Fix crash when switching surface on Huawei P9 Lite

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsPlaylistParser.java

@@ -123,7 +123,8 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
               + METHOD_SAMPLE_AES_CENC
               + "|"
               + METHOD_SAMPLE_AES_CTR
-              + ")");
+              + ")"
+              + "\\s*(,|$)");
   private static final Pattern REGEX_KEYFORMAT = Pattern.compile("KEYFORMAT=\"(.+?)\"");
   private static final Pattern REGEX_URI = Pattern.compile("URI=\"(.+?)\"");
   private static final Pattern REGEX_IV = Pattern.compile("IV=([^,.*]+)");

library/hls/src/test/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylistParserTest.java

@@ -140,6 +140,78 @@ public class HlsMediaPlaylistParserTest {
     assertThat(segment.url).isEqualTo("https://priv.example.com/fileSequence2683.ts");
   }
 
+  @Test
+  public void testParseSampleAesMethod() throws Exception {
+    Uri playlistUri = Uri.parse("https://example.com/test.m3u8");
+    String playlistString =
+        "#EXTM3U\n"
+            + "#EXT-X-MEDIA-SEQUENCE:0\n"
+            + "#EXTINF:8,\n"
+            + "https://priv.example.com/1.ts\n"
+            + "\n"
+            + "#EXT-X-KEY:METHOD=SAMPLE-AES,URI="
+            + "\"data:text/plain;base64,VGhpcyBpcyBhbiBlYXN0ZXIgZWdn\","
+            + "IV=0x9358382AEB449EE23C3D809DA0B9CCD3,KEYFORMATVERSIONS=\"1\","
+            + "KEYFORMAT=\"com.widevine\",IV=0x1566B\n"
+            + "#EXTINF:8,\n"
+            + "https://priv.example.com/2.ts\n"
+            + "#EXT-X-ENDLIST\n";
+    InputStream inputStream =
+        new ByteArrayInputStream(playlistString.getBytes(Charset.forName(C.UTF8_NAME)));
+    HlsMediaPlaylist playlist =
+        (HlsMediaPlaylist) new HlsPlaylistParser().parse(playlistUri, inputStream);
+    assertThat(playlist.drmInitData.schemeType).isEqualTo(C.CENC_TYPE_cbcs);
+    assertThat(playlist.drmInitData.get(0).matches(C.WIDEVINE_UUID)).isTrue();
+  }
+
+  @Test
+  public void testParseSampleAesCencMethod() throws Exception {
+    Uri playlistUri = Uri.parse("https://example.com/test.m3u8");
+    String playlistString =
+        "#EXTM3U\n"
+            + "#EXT-X-MEDIA-SEQUENCE:0\n"
+            + "#EXTINF:8,\n"
+            + "https://priv.example.com/1.ts\n"
+            + "\n"
+            + "#EXT-X-KEY:URI=\"data:text/plain;base64,VGhpcyBpcyBhbiBlYXN0ZXIgZWdn\","
+            + "IV=0x9358382AEB449EE23C3D809DA0B9CCD3,KEYFORMATVERSIONS=\"1\","
+            + "KEYFORMAT=\"urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed\","
+            + "IV=0x1566B,METHOD=SAMPLE-AES-CENC \n"
+            + "#EXTINF:8,\n"
+            + "https://priv.example.com/2.ts\n"
+            + "#EXT-X-ENDLIST\n";
+    InputStream inputStream =
+        new ByteArrayInputStream(playlistString.getBytes(Charset.forName(C.UTF8_NAME)));
+    HlsMediaPlaylist playlist =
+        (HlsMediaPlaylist) new HlsPlaylistParser().parse(playlistUri, inputStream);
+    assertThat(playlist.drmInitData.schemeType).isEqualTo(C.CENC_TYPE_cenc);
+    assertThat(playlist.drmInitData.get(0).matches(C.WIDEVINE_UUID)).isTrue();
+  }
+
+  @Test
+  public void testParseSampleAesCtrMethod() throws Exception {
+    Uri playlistUri = Uri.parse("https://example.com/test.m3u8");
+    String playlistString =
+        "#EXTM3U\n"
+            + "#EXT-X-MEDIA-SEQUENCE:0\n"
+            + "#EXTINF:8,\n"
+            + "https://priv.example.com/1.ts\n"
+            + "\n"
+            + "#EXT-X-KEY:METHOD=SAMPLE-AES-CTR,URI="
+            + "\"data:text/plain;base64,VGhpcyBpcyBhbiBlYXN0ZXIgZWdn\","
+            + "IV=0x9358382AEB449EE23C3D809DA0B9CCD3,KEYFORMATVERSIONS=\"1\","
+            + "KEYFORMAT=\"com.widevine\",IV=0x1566B\n"
+            + "#EXTINF:8,\n"
+            + "https://priv.example.com/2.ts\n"
+            + "#EXT-X-ENDLIST\n";
+    InputStream inputStream =
+        new ByteArrayInputStream(playlistString.getBytes(Charset.forName(C.UTF8_NAME)));
+    HlsMediaPlaylist playlist =
+        (HlsMediaPlaylist) new HlsPlaylistParser().parse(playlistUri, inputStream);
+    assertThat(playlist.drmInitData.schemeType).isEqualTo(C.CENC_TYPE_cenc);
+    assertThat(playlist.drmInitData.get(0).matches(C.WIDEVINE_UUID)).isTrue();
+  }
+
   @Test
   public void testGapTag() throws IOException {
     Uri playlistUri = Uri.parse("https://example.com/test2.m3u8");