shadow color: support in json serializer, fill in some style gaps

api/src/main/java/net/kyori/adventure/text/format/Style.java

@@ -562,7 +562,7 @@ default boolean hasDecoration(final @NotNull TextDecoration decoration) {
    */
   enum Merge {
     /**
-     * Merges {@link Style#color()}.
+     * Merges {@link Style#color()} and {@link Style#shadowColor()}.
      *
      * @since 4.0.0
      */

api/src/main/java/net/kyori/adventure/text/format/StyleImpl.java

@@ -223,6 +223,10 @@ final class StyleImpl implements Style {
       builder.color(null);
     }
 
+    if (Objects.equals(this.shadowColor(), that.shadowColor())) {
+      builder.shadowColor(null);
+    }
+
     for (int i = 0, length = DecorationMap.DECORATIONS.length; i < length; i++) {
       final TextDecoration decoration = DecorationMap.DECORATIONS[i];
       if (this.decoration(decoration) == that.decoration(decoration)) {
@@ -269,6 +273,7 @@ public boolean isEmpty() {
       this.decorations.examinableProperties(),
       Stream.of(
         ExaminableProperty.of("color", this.color),
+        ExaminableProperty.of("shadowColor", this.shadowColor),
         ExaminableProperty.of("clickEvent", this.clickEvent),
         ExaminableProperty.of("hoverEvent", this.hoverEvent),
         ExaminableProperty.of("insertion", this.insertion),
@@ -289,6 +294,7 @@ public boolean equals(final @Nullable Object other) {
     final StyleImpl that = (StyleImpl) other;
     return Objects.equals(this.color, that.color)
       && this.decorations.equals(that.decorations)
+      && Objects.equals(this.shadowColor, that.shadowColor)
       && Objects.equals(this.clickEvent, that.clickEvent)
       && Objects.equals(this.hoverEvent, that.hoverEvent)
       && Objects.equals(this.insertion, that.insertion)
@@ -298,6 +304,7 @@ public boolean equals(final @Nullable Object other) {
   @Override
   public int hashCode() {
     int result = Objects.hashCode(this.color);
+    result = (31 * result) + Objects.hashCode(this.shadowColor);
     result = (31 * result) + this.decorations.hashCode();
     result = (31 * result) + Objects.hashCode(this.clickEvent);
     result = (31 * result) + Objects.hashCode(this.hoverEvent);
@@ -321,6 +328,7 @@ static final class BuilderImpl implements Builder {
 
     BuilderImpl(final @NotNull StyleImpl style) {
       this.color = style.color;
+      this.shadowColor = style.shadowColor;
       this.decorations = new EnumMap<>(style.decorations);
       this.clickEvent = style.clickEvent;
       this.hoverEvent = style.hoverEvent;
@@ -418,6 +426,13 @@ static final class BuilderImpl implements Builder {
             this.color(color);
           }
         }
+
+        final ShadowColor shadowColor = that.shadowColor();
+        if (shadowColor != null) {
+          if (strategy == Merge.Strategy.ALWAYS || (strategy == Merge.Strategy.IF_ABSENT_ON_TARGET && this.shadowColor == null)) {
+            this.shadowColor(shadowColor);
+          }
+        }
       }
 
       if (merges.contains(Merge.DECORATIONS)) {
@@ -481,6 +496,7 @@ static final class BuilderImpl implements Builder {
 
     private boolean isEmpty() {
       return this.color == null
+        && this.shadowColor == null
         && this.decorations.values().stream().allMatch(state -> state == TextDecoration.State.NOT_SET)
         && this.clickEvent == null
         && this.hoverEvent == null

text-serializer-gson/src/main/java/net/kyori/adventure/text/serializer/gson/SerializerFactory.java

@@ -90,7 +90,7 @@ public <T> TypeAdapter<T> create(final Gson gson, final TypeToken<T> type) {
     } else if (COLOR_TYPE.isAssignableFrom(rawType)) {
       return (TypeAdapter<T>) (this.features.value(JSONOptions.EMIT_RGB) ? TextColorSerializer.INSTANCE : TextColorSerializer.DOWNSAMPLE_COLOR);
     } else if (SHADOW_COLOR_TYPE.isAssignableFrom(rawType)) {
-      return (TypeAdapter<T>) ShadowColorSerializer.INSTANCE;
+      return (TypeAdapter<T>) ShadowColorSerializer.create(this.features);
     } else if (TEXT_DECORATION_TYPE.isAssignableFrom(rawType)) {
       return (TypeAdapter<T>) TextDecorationSerializer.INSTANCE;
     } else if (BLOCK_NBT_POS_TYPE.isAssignableFrom(rawType)) {

text-serializer-gson/src/main/java/net/kyori/adventure/text/serializer/gson/ShadowColorSerializer.java

@@ -23,27 +23,71 @@
  */
 package net.kyori.adventure.text.serializer.gson;
 
+import com.google.gson.JsonParseException;
 import com.google.gson.TypeAdapter;
 import com.google.gson.stream.JsonReader;
 import com.google.gson.stream.JsonToken;
 import com.google.gson.stream.JsonWriter;
 import java.io.IOException;
 import net.kyori.adventure.text.format.ShadowColor;
+import net.kyori.adventure.text.serializer.json.JSONOptions;
+import net.kyori.option.OptionState;
 
 final class ShadowColorSerializer extends TypeAdapter<ShadowColor> {
-  static final TypeAdapter<ShadowColor> INSTANCE = new ShadowColorSerializer().nullSafe();
+  static TypeAdapter<ShadowColor> create(final OptionState options) {
+    return new ShadowColorSerializer(options.value(JSONOptions.SHADOW_COLOR_MODE) == JSONOptions.ShadowColorEmitMode.EMIT_ARRAY).nullSafe();
+  }
+
+  private final boolean emitArray;
+
+  private ShadowColorSerializer(final boolean emitArray) {
+    this.emitArray = emitArray;
+  }
 
   @Override
   public void write(final JsonWriter out, final ShadowColor value) throws IOException {
-    out.value(value.value());
+    if (this.emitArray) {
+      out.beginArray()
+        .value(componentAsFloat(value.red()))
+        .value(componentAsFloat(value.green()))
+        .value(componentAsFloat(value.blue()))
+        .value(componentAsFloat(value.alpha()))
+        .endArray();
+
+    } else {
+      out.value(value.value());
+    }
   }
 
   @Override
   public ShadowColor read(final JsonReader in) throws IOException {
     if (in.peek() == JsonToken.BEGIN_ARRAY) {
-      throw new UnsupportedOperationException(); // TODO
+      in.beginArray();
+      final double r = in.nextDouble();
+      final double g = in.nextDouble();
+      final double b = in.nextDouble();
+      final double a = in.nextDouble();
+      if (in.peek() != JsonToken.END_ARRAY) {
+        throw new JsonParseException("Failed to parse shadow colour at " + in.getPath() + ": expected end of 4-element array but got " + in.peek() + " instead.");
+      }
+      in.endArray();
+
+      return ShadowColor.shadowColor(
+        componentFromFloat(r),
+        componentFromFloat(g),
+        componentFromFloat(b),
+        componentFromFloat(a)
+      );
     }
 
     return ShadowColor.shadowColor(in.nextInt());
   }
+
+  static float componentAsFloat(final int element) {
+    return (float) element / 0xff;
+  }
+
+  static int componentFromFloat(final double element) {
+    return (int) ((float) element) * 0xff;
+  }
 }

text-serializer-gson/src/main/java/net/kyori/adventure/text/serializer/gson/StyleSerializer.java

@@ -91,6 +91,7 @@ static TypeAdapter<Style> create(final net.kyori.adventure.text.serializer.json.
       hoverMode == JSONOptions.HoverEventValueMode.LEGACY_ONLY || hoverMode == JSONOptions.HoverEventValueMode.BOTH,
       hoverMode == JSONOptions.HoverEventValueMode.MODERN_ONLY || hoverMode == JSONOptions.HoverEventValueMode.BOTH,
       features.value(JSONOptions.VALIDATE_STRICT_EVENTS),
+      features.value(JSONOptions.SHADOW_COLOR_MODE) != JSONOptions.ShadowColorEmitMode.NONE,
       gson
     ).nullSafe();
   }
@@ -99,19 +100,22 @@ static TypeAdapter<Style> create(final net.kyori.adventure.text.serializer.json.
   private final boolean emitLegacyHover;
   private final boolean emitModernHover;
   private final boolean strictEventValues;
+  private final boolean emitShadowColor;
   private final Gson gson;
 
   private StyleSerializer(
     final net.kyori.adventure.text.serializer.json.@Nullable LegacyHoverEventSerializer legacyHover,
     final boolean emitLegacyHover,
     final boolean emitModernHover,
     final boolean strictEventValues,
+    final boolean emitShadowColor,
     final Gson gson
   ) {
     this.legacyHover = legacyHover;
     this.emitLegacyHover = emitLegacyHover;
     this.emitModernHover = emitModernHover;
     this.strictEventValues = strictEventValues;
+    this.emitShadowColor = emitShadowColor;
     this.gson = gson;
   }
 
@@ -131,6 +135,8 @@ public Style read(final JsonReader in) throws IOException {
         } else if (color.decoration != null) {
           style.decoration(color.decoration, TextDecoration.State.TRUE);
         }
+      } else if (fieldName.equals(SHADOW_COLOR)) {
+        style.shadowColor(this.gson.fromJson(in, SerializerFactory.SHADOW_COLOR_TYPE));
       } else if (TextDecoration.NAMES.keys().contains(fieldName)) {
         style.decoration(TextDecoration.NAMES.value(fieldName), GsonHacks.readBoolean(in));
       } else if (fieldName.equals(INSERTION)) {
@@ -269,7 +275,7 @@ public void write(final JsonWriter out, final Style value) throws IOException {
     }
 
     final @Nullable ShadowColor shadowColor = value.shadowColor();
-    if (shadowColor != null) {
+    if (shadowColor != null && this.emitShadowColor) {
       out.name(SHADOW_COLOR);
       this.gson.toJson(shadowColor, SerializerFactory.SHADOW_COLOR_TYPE, out);
     }

text-serializer-json/src/main/java/net/kyori/adventure/text/serializer/json/JSONOptions.java

@@ -42,6 +42,7 @@ private JSONOptions() {
   private static final int VERSION_1_16 = 2526; // 20w16a
   private static final int VERSION_1_20_3 = 3679; // 23w40a
   private static final int VERSION_1_20_5 = 3819; // 24w09a
+  private static final int VERSION_1_21_4 = 4174; // 24w44a
 
   /**
    * Whether to emit RGB text.
@@ -99,6 +100,13 @@ private JSONOptions() {
    */
   public static final Option<ShowItemHoverDataMode> SHOW_ITEM_HOVER_DATA_MODE = Option.enumOption(key("emit/show_item_hover_data"), ShowItemHoverDataMode.class, ShowItemHoverDataMode.EMIT_EITHER);
 
+  /**
+   * How to emit shadow colour data.
+   *
+   * @since 4.18.0
+   */
+  public static final Option<ShadowColorEmitMode> SHADOW_COLOR_MODE = Option.enumOption(key("emit/shadow_color"), ShadowColorEmitMode.class, ShadowColorEmitMode.EMIT_INTEGER);
+
   /**
    * Versioned by world data version.
    */
@@ -111,6 +119,7 @@ private JSONOptions() {
         .value(VALIDATE_STRICT_EVENTS, false)
         .value(EMIT_DEFAULT_ITEM_HOVER_QUANTITY, false)
         .value(SHOW_ITEM_HOVER_DATA_MODE, ShowItemHoverDataMode.EMIT_LEGACY_NBT)
+        .value(SHADOW_COLOR_MODE, ShadowColorEmitMode.NONE)
     )
     .version(
       VERSION_1_16,
@@ -128,6 +137,10 @@ private JSONOptions() {
       b -> b.value(EMIT_DEFAULT_ITEM_HOVER_QUANTITY, true)
         .value(SHOW_ITEM_HOVER_DATA_MODE, ShowItemHoverDataMode.EMIT_DATA_COMPONENTS)
     )
+    .version(
+      VERSION_1_21_4,
+      b -> b.value(SHADOW_COLOR_MODE, ShadowColorEmitMode.EMIT_INTEGER)
+    )
     .build();
 
   /**
@@ -141,6 +154,7 @@ private JSONOptions() {
     .value(EMIT_COMPACT_TEXT_COMPONENT, false)
     .value(VALIDATE_STRICT_EVENTS, false)
     .value(SHOW_ITEM_HOVER_DATA_MODE, ShowItemHoverDataMode.EMIT_EITHER)
+    .value(SHADOW_COLOR_MODE, ShadowColorEmitMode.EMIT_INTEGER)
     .build();
 
   private static String key(final String value) {
@@ -220,4 +234,30 @@ public enum ShowItemHoverDataMode {
      */
     EMIT_EITHER,
   }
+
+  /**
+   * How text shadow colors should be emitted.
+   *
+   * @since 4.18.0
+   * @sinceMinecraft 1.21.4
+   */
+  public enum ShadowColorEmitMode {
+    /**
+     * Do not emit shadow colours.
+     */
+    NONE,
+    /**
+     * Emit as a single packed integer value containing, in order, ARGB bytes.
+     *
+     * @since 4.18.0
+     */
+    EMIT_INTEGER,
+    /**
+     * Emit a colour as 4-element float array of the RGBA components of the colour.
+     *
+     * @since 4.18.0
+     */
+    EMIT_ARRAY
+
+  }
 }