Add default colors list in WebvttCueParser for text foreground class matching with tests

TIL: papayawhip is a color

library/core/src/main/java/com/google/android/exoplayer2/text/webvtt/WebvttCueParser.java

@@ -40,7 +40,6 @@ import com.google.android.exoplayer2.text.Cue;
 import com.google.android.exoplayer2.text.span.HorizontalTextInVerticalContextSpan;
 import com.google.android.exoplayer2.text.span.RubySpan;
 import com.google.android.exoplayer2.util.Assertions;
-import com.google.android.exoplayer2.util.ColorParser;
 import com.google.android.exoplayer2.util.Log;
 import com.google.android.exoplayer2.util.ParsableByteArray;
 import com.google.android.exoplayer2.util.Util;
@@ -49,7 +48,9 @@ import java.lang.annotation.Retention;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
@@ -138,6 +139,20 @@ public final class WebvttCueParser {
 
   private static final String TAG = "WebvttCueParser";
 
+  private static final Map<String, Integer> DEFAULT_COLORS;
+
+  static {
+    DEFAULT_COLORS = new HashMap<>();
+    DEFAULT_COLORS.put("black", 0xFF000000);
+    DEFAULT_COLORS.put("blue", 0xFF0000FF);
+    DEFAULT_COLORS.put("cyan", 0xFF00FFFF);
+    DEFAULT_COLORS.put("lime", 0xFF00FF00);
+    DEFAULT_COLORS.put("magenta", 0xFFFF00FF);
+    DEFAULT_COLORS.put("red", 0xFFFF0000);
+    DEFAULT_COLORS.put("white", 0xFFFFFFFF);
+    DEFAULT_COLORS.put("yellow", 0xFFFFFF00);
+  }
+
   /**
    * Parses the next valid WebVTT cue in a parsable array, including timestamps, settings and text.
    *
@@ -535,9 +550,9 @@ public final class WebvttCueParser {
   private static void applySupportedClasses(SpannableStringBuilder text, String[] classes,
       int start, int end) {
     for (String className : classes) {
-      if (ColorParser.isNamedColor(className)) {
-        int color = ColorParser.parseCssColor(className);
-        text.setSpan(new ForegroundColorSpan(color), start, end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+      if (DEFAULT_COLORS.containsKey(className)) {
+        int color = DEFAULT_COLORS.get(Util.toLowerInvariant(className));
+        text.setSpan(new ForegroundColorSpan(color), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
       }
     }
   }

library/core/src/main/java/com/google/android/exoplayer2/util/ColorParser.java

@@ -43,10 +43,6 @@ public final class ColorParser {
 
   private static final Map<String, Integer> COLOR_MAP;
 
-  public static boolean isNamedColor(String expression) {
-    return COLOR_MAP.containsKey(expression);
-  }
-
   /**
    * Parses a TTML color expression.
    *

library/core/src/test/java/com/google/android/exoplayer2/text/webvtt/WebvttCueParserTest.java

@@ -80,6 +80,22 @@ public final class WebvttCueParserTest {
   }
 
   @Test
+  public void testForegroundTextColorClass() throws Exception {
+    Spanned text = parseCueText("In this sentence <c.red>this text</c> is red");
+
+    assertThat(text.toString()).isEqualTo("In this sentence this text is red");
+    assertThat(text).hasForegroundColorSpanBetween("In this sentence ".length(), "In this sentence this text".length());
+  }
+
+  @Test
+  public void testUnsupportedColorForForegroundTextColorClass() throws Exception {
+    Spanned text = parseCueText("In this sentence <c.papayawhip>this text</c> is not papaya");
+
+    assertThat(text.toString()).isEqualTo("In this sentence this text is not papaya");
+    assertThat(text).hasNoSpans();
+  }
+
+  @Test
   public void testParseWellFormedUnclosedEndAtCueEnd() throws Exception {
     Spanned text = parseCueText("An <u some trailing stuff>unclosed u tag with "
         + "<i>italic</i> inside");