From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Tue, 5 Dec 2023 16:47:40 -0800
Subject: [PATCH] initial work on native Adventure codecs

== AT ==
public net.minecraft.network.chat.HoverEvent$ItemStackInfo item
public net.minecraft.network.chat.HoverEvent$ItemStackInfo count
public net.minecraft.network.chat.HoverEvent$ItemStackInfo tag
public net.minecraft.network.chat.contents.TranslatableContents filterAllowedArguments(Ljava/lang/Object;)Lcom/mojang/serialization/DataResult;

diff --git a/src/main/java/io/papermc/paper/adventure/AdventureCodecs.java b/src/main/java/io/papermc/paper/adventure/AdventureCodecs.java
new file mode 100644
index 0000000000000000000000000000000000000000..db13894e2710b933f69f3adaa7e728461e3cf049
--- /dev/null
+++ b/src/main/java/io/papermc/paper/adventure/AdventureCodecs.java
@@ -0,0 +1,277 @@
+package io.papermc.paper.adventure;
+
+import com.mojang.datafixers.util.Either;
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
+import com.mojang.serialization.MapCodec;
+import com.mojang.serialization.codecs.RecordCodecBuilder;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
+import java.util.function.Consumer;
+import java.util.function.Function;
+import net.kyori.adventure.key.Key;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.KeybindComponent;
+import net.kyori.adventure.text.ScoreComponent;
+import net.kyori.adventure.text.TextComponent;
+import net.kyori.adventure.text.TranslatableComponent;
+import net.kyori.adventure.text.event.ClickEvent;
+import net.kyori.adventure.text.event.HoverEvent;
+import net.kyori.adventure.text.format.NamedTextColor;
+import net.kyori.adventure.text.format.Style;
+import net.kyori.adventure.text.format.TextColor;
+import net.kyori.adventure.text.format.TextDecoration;
+import net.minecraft.core.UUIDUtil;
+import net.minecraft.core.registries.BuiltInRegistries;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.network.chat.ComponentSerialization;
+import net.minecraft.network.chat.contents.KeybindContents;
+import net.minecraft.network.chat.contents.ScoreContents;
+import net.minecraft.network.chat.contents.TranslatableContents;
+import net.minecraft.util.ExtraCodecs;
+import net.minecraft.util.StringRepresentable;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.item.ItemStack;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.checkerframework.framework.qual.DefaultQualifier;
+import org.intellij.lang.annotations.Subst;
+
+import static java.util.Objects.requireNonNull;
+import static net.kyori.adventure.text.Component.text;
+import static net.minecraft.util.ExtraCodecs.strictOptionalField;
+
+@DefaultQualifier(NonNull.class)
+public final class AdventureCodecs {
+
+    public static final Codec<Component> COMPONENT_CODEC = ExtraCodecs.recursive("adventure Component", AdventureCodecs::createCodec);
+
+    private static final Codec<TextColor> TEXT_COLOR_CODEC = Codec.STRING.comapFlatMap(s -> {
+        if (s.startsWith("#")) {
+            @Nullable TextColor value = TextColor.fromHexString(s);
+            return value != null ? DataResult.success(value) : DataResult.error(() -> "Cannot convert " + s + " to adventure TextColor");
+        } else {
+            final @Nullable NamedTextColor value = NamedTextColor.NAMES.value(s);
+            return value != null ? DataResult.success(value) : DataResult.error(() -> "Cannot convert " + s + " to adventure NamedTextColor");
+        }
+    }, textColor -> {
+        if (textColor instanceof NamedTextColor named) {
+            return NamedTextColor.NAMES.keyOrThrow(named);
+        } else {
+            return textColor.asHexString();
+        }
+    });
+
+    private static final Codec<Key> KEY_CODEC = Codec.STRING.comapFlatMap(s -> {
+        return Key.parseable(s) ? DataResult.success(Key.key(s)) : DataResult.error(() -> "Cannot convert " + s + " to adventure Key");
+    }, Key::asString);
+
+    private static final Codec<ClickEvent.Action> CLICK_EVENT_ACTION_CODEC = Codec.STRING.comapFlatMap(s -> {
+        final ClickEvent.@Nullable Action value = ClickEvent.Action.NAMES.value(s);
+        return value != null ? DataResult.success(value) : DataResult.error(() -> "Cannot convert " + s + " to adventure ClickEvent$Action");
+    }, ClickEvent.Action.NAMES::keyOrThrow);
+    private static final Codec<ClickEvent> CLICK_EVENT_CODEC = RecordCodecBuilder.create((instance) -> {
+        return instance.group(
+            CLICK_EVENT_ACTION_CODEC.fieldOf("action").forGetter(ClickEvent::action),
+            Codec.STRING.fieldOf("value").forGetter(ClickEvent::value)
+        ).apply(instance, ClickEvent::clickEvent);
+    });
+
+    private static final Codec<HoverEvent.ShowEntity> SHOW_ENTITY_CODEC = RecordCodecBuilder.create((instance) -> {
+        return instance.group(
+            KEY_CODEC.fieldOf("type").forGetter(HoverEvent.ShowEntity::type),
+            UUIDUtil.LENIENT_CODEC.fieldOf("id").forGetter(HoverEvent.ShowEntity::id),
+            strictOptionalField(COMPONENT_CODEC, "name").forGetter(he -> Optional.ofNullable(he.name()))
+        ).apply(instance, (key, uuid, component) -> {
+            return HoverEvent.ShowEntity.showEntity(key, uuid, component.orElse(null));
+        });
+    });
+
+    private static final Codec<HoverEvent.ShowItem> SHOW_ITEM_CODEC = net.minecraft.network.chat.HoverEvent.ItemStackInfo.CODEC.xmap(isi -> {
+        @Subst("key") final String typeKey = BuiltInRegistries.ITEM.getKey(isi.item).toString();
+        return HoverEvent.ShowItem.showItem(Key.key(typeKey), isi.count, PaperAdventure.asBinaryTagHolder(isi.tag.orElse(null)));
+    }, si -> {
+        final Item itemType = BuiltInRegistries.ITEM.get(PaperAdventure.asVanilla(si.item()));
+        final ItemStack stack;
+        try {
+            final @Nullable CompoundTag tag = si.nbt() != null ? si.nbt().get(PaperAdventure.NBT_CODEC) : null;
+            stack = new ItemStack(BuiltInRegistries.ITEM.wrapAsHolder(itemType), si.count(), Optional.ofNullable(tag));
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+        return new net.minecraft.network.chat.HoverEvent.ItemStackInfo(stack);
+    });
+
+    // TODO legacies
+    private static final HoverEventType<HoverEvent.ShowEntity> SHOW_ENTITY_HOVER_EVENT_TYPE = new HoverEventType<>(SHOW_ENTITY_CODEC, HoverEvent.Action.SHOW_ENTITY, "show_entity");
+    private static final HoverEventType<HoverEvent.ShowItem> SHOW_ITEM_HOVER_EVENT_TYPE = new HoverEventType<>(SHOW_ITEM_CODEC, HoverEvent.Action.SHOW_ITEM, "show_item");
+    private static final HoverEventType<Component> SHOW_TEXT_HOVER_EVENT_TYPE = new HoverEventType<>(COMPONENT_CODEC, HoverEvent.Action.SHOW_TEXT, "show_text");
+    private static final Codec<HoverEventType<?>> HOVER_EVENT_TYPE_CODEC = StringRepresentable.fromValues(() -> new HoverEventType<?>[]{ SHOW_ENTITY_HOVER_EVENT_TYPE, SHOW_ITEM_HOVER_EVENT_TYPE, SHOW_TEXT_HOVER_EVENT_TYPE });
+
+    private record HoverEventType<V>(Codec<HoverEvent<V>> codec, String id) implements StringRepresentable {
+        private HoverEventType(final Codec<V> contentCodec, final HoverEvent.Action<V> action, final String id) {
+            this(contentCodec.xmap(v -> {
+                return HoverEvent.hoverEvent(action, v);
+            }, HoverEvent::value), id);
+        }
+        @Override
+        public String getSerializedName() {
+            return this.id;
+        }
+    }
+
+    private static final MapCodec<HoverEvent<?>> HOVER_EVENT_MAP_CODEC = HOVER_EVENT_TYPE_CODEC.dispatchMap("action", he -> {
+        if (he.action() == HoverEvent.Action.SHOW_ENTITY) {
+            return SHOW_ENTITY_HOVER_EVENT_TYPE;
+        } else if (he.action() == HoverEvent.Action.SHOW_ITEM) {
+            return SHOW_ITEM_HOVER_EVENT_TYPE;
+        } else if (he.action() == HoverEvent.Action.SHOW_TEXT) {
+            return SHOW_TEXT_HOVER_EVENT_TYPE;
+        } else {
+            throw new IllegalStateException();
+        }
+    }, HoverEventType::codec);
+
+    public static final MapCodec<Style> STYLE_CODEC = RecordCodecBuilder.mapCodec((instance) -> {
+        return instance.group(
+            strictOptionalField(TEXT_COLOR_CODEC, "color").forGetter(styleGetter(Style::color)),
+            strictOptionalField(Codec.BOOL, "bold").forGetter(decorationGetter(TextDecoration.BOLD)),
+            strictOptionalField(Codec.BOOL, "italic").forGetter(decorationGetter(TextDecoration.ITALIC)),
+            strictOptionalField(Codec.BOOL, "underlined").forGetter(decorationGetter(TextDecoration.UNDERLINED)),
+            strictOptionalField(Codec.BOOL, "strikethrough").forGetter(decorationGetter(TextDecoration.STRIKETHROUGH)),
+            strictOptionalField(Codec.BOOL, "obfuscated").forGetter(decorationGetter(TextDecoration.OBFUSCATED)),
+            strictOptionalField(CLICK_EVENT_CODEC, "clickEvent").forGetter(styleGetter(Style::clickEvent)),
+            strictOptionalField(HOVER_EVENT_MAP_CODEC.codec(), "hoverEvent").forGetter(styleGetter(Style::hoverEvent)),
+            strictOptionalField(Codec.STRING, "insertion").forGetter(styleGetter(Style::insertion)),
+            strictOptionalField(KEY_CODEC, "font").forGetter(styleGetter(Style::font))
+            ).apply(instance, (textColor, bold, italic, underlined, strikethrough, obfuscated, clickEvent, hoverEvent, insertion, font) -> {
+                return Style.style(builder -> {
+                    textColor.ifPresent(builder::color);
+                    bold.ifPresent(styleBooleanConsumer(builder, TextDecoration.BOLD));
+                    italic.ifPresent(styleBooleanConsumer(builder, TextDecoration.ITALIC));
+                    underlined.ifPresent(styleBooleanConsumer(builder, TextDecoration.UNDERLINED));
+                    strikethrough.ifPresent(styleBooleanConsumer(builder, TextDecoration.STRIKETHROUGH));
+                    obfuscated.ifPresent(styleBooleanConsumer(builder, TextDecoration.OBFUSCATED));
+                    clickEvent.ifPresent(builder::clickEvent);
+                    hoverEvent.ifPresent(builder::hoverEvent);
+                    insertion.ifPresent(builder::insertion);
+                    font.ifPresent(builder::font);
+                });
+        });
+    });
+    private static Consumer<Boolean> styleBooleanConsumer(final Style.Builder builder, final TextDecoration decoration) {
+        return b -> builder.decoration(decoration, b);
+    }
+
+    private static Function<Style, Optional<Boolean>> decorationGetter(final TextDecoration decoration) {
+        return style -> Optional.ofNullable(style.decoration(decoration) == TextDecoration.State.NOT_SET ? null : style.decoration(decoration) == TextDecoration.State.TRUE);
+    }
+
+    private static <T> Function<Style, Optional<T>> styleGetter(final Function<Style, @Nullable T> getter) {
+        return style -> Optional.ofNullable(getter.apply(style));
+    }
+
+    private static final MapCodec<TextComponent> TEXT_COMPONENT_CODEC = RecordCodecBuilder.mapCodec((instance) -> {
+        return instance.group(Codec.STRING.fieldOf("text").forGetter(TextComponent::content)).apply(instance, Component::text);
+    });
+    private static final Codec<Object> PRIMITIVE_ARG_CODEC = ExtraCodecs.validate(ExtraCodecs.JAVA, TranslatableContents::filterAllowedArguments);
+    private static final Codec<Component> ARG_CODEC = Codec.either(PRIMITIVE_ARG_CODEC, COMPONENT_CODEC).xmap((either) -> {
+        return either.map((object) -> {
+            if (object instanceof Integer integer) {
+                return text(integer);
+            } else if (object instanceof Long l) {
+                return text(l);
+            } else if (object instanceof String s) {
+                return text(s);
+            } else if (object instanceof Boolean bool) {
+                return text(bool);
+            } else if (object instanceof Float f) {
+                return text(f);
+            } else if (object instanceof Double d) {
+                return text(d);
+            } else if (object instanceof Short s) {
+                return text(s);
+            } else {
+                throw new IllegalStateException();
+            }
+        }, (text) -> text);
+    }, Either::right);
+    private static final MapCodec<TranslatableComponent> TRANSLATABLE_COMPONENT_CODEC = RecordCodecBuilder.mapCodec((instance) -> {
+        return instance.group(
+            Codec.STRING.fieldOf("translate").forGetter(TranslatableComponent::key),
+            Codec.STRING.fieldOf("fallback").forGetter(TranslatableComponent::fallback),
+            strictOptionalField(ARG_CODEC.listOf(), "with").forGetter(c -> c.args().isEmpty() ? Optional.empty() : Optional.of(c.args()))
+        ).apply(instance, (key, fallback, components) -> {
+            return Component.translatable(key, components.orElse(Collections.emptyList())).fallback(fallback);
+        });
+    });
+    private static final MapCodec<KeybindComponent> KEYBIND_COMPONENT_CODEC = KeybindContents.CODEC.xmap(k -> Component.keybind(k.getName()), k -> new KeybindContents(k.keybind()));
+    private static final MapCodec<ScoreComponent> SCORE_COMPONENT_CODEC = ScoreContents.INNER_CODEC.xmap(s -> Component.score(s.getName(), s.getObjective()), s -> new ScoreContents(s.name(), s.objective()));
+
+    private record ComponentType<C extends Component>(MapCodec<C> codec, String id) implements StringRepresentable {
+        @Override
+        public String getSerializedName() {
+            return this.id;
+        }
+    }
+
+    private static final ComponentType<TextComponent> PLAIN = new ComponentType<>(TEXT_COMPONENT_CODEC, "text");
+    private static final ComponentType<TranslatableComponent> TRANSLATABLE = new ComponentType<>(TRANSLATABLE_COMPONENT_CODEC, "translatable");
+    private static final ComponentType<ScoreComponent> SCORE = new ComponentType<>(SCORE_COMPONENT_CODEC, "score");
+    private static final ComponentType<KeybindComponent> KEYBIND = new ComponentType<>(KEYBIND_COMPONENT_CODEC, "keybind");
+
+    private static Codec<Component> createCodec(final Codec<Component> selfCodec) {
+        final ComponentType<?>[] types = new ComponentType<?>[]{PLAIN, TRANSLATABLE, SCORE};
+        final MapCodec<Component> legacyCodec = ComponentSerialization.createLegacyComponentMatcher(types, ComponentType::codec, component -> {
+            if (component instanceof TextComponent) {
+                return PLAIN;
+            } else if (component instanceof TranslatableComponent) {
+                return TRANSLATABLE;
+            } else if (component instanceof KeybindComponent) {
+                return KEYBIND;
+            } else if (component instanceof ScoreComponent) {
+                return SCORE;
+            } else {
+                throw new IllegalStateException();
+            }
+        }, "type");
+
+        final Codec<Component> codec = RecordCodecBuilder.create((instance) -> {
+            return instance.group(legacyCodec.forGetter(Function.identity()), ExtraCodecs.strictOptionalField(ExtraCodecs.nonEmptyList(selfCodec.listOf()), "extra", List.of()).forGetter(Component::children), STYLE_CODEC.forGetter(Component::style)).apply(instance, (component, children, style) -> {
+                return component.style(style).children(children);
+            });
+        });
+        return Codec.either(Codec.either(Codec.STRING, ExtraCodecs.nonEmptyList(selfCodec.listOf())), codec).xmap((either) -> {
+            return either.map((either2) -> {
+                return either2.map(Component::text, AdventureCodecs::createFromList);
+            }, (text) -> {
+                return text;
+            });
+        }, (text) -> {
+            final @Nullable String string = tryCollapseToString(text);
+            return string != null ? Either.left(Either.left(string)) : Either.right(text);
+        });
+    }
+
+    private static @Nullable String tryCollapseToString(final Component component) {
+        if (component instanceof final TextComponent textComponent) {
+            if (component.children().isEmpty() && component.style().isEmpty()) {
+                return textComponent.content();
+            }
+        }
+        return null;
+    }
+
+    private static Component createFromList(final List<Component> components) {
+        Component component = components.get(0);
+        for (int i = 1; i < components.size(); i++) {
+            component = component.append(components.get(i));
+        }
+        return component;
+    }
+
+    private AdventureCodecs() {
+    }
+}
diff --git a/src/main/java/io/papermc/paper/adventure/PaperAdventure.java b/src/main/java/io/papermc/paper/adventure/PaperAdventure.java
index db54a9c32578defa02fa58dc694c96684a4885ac..4ded541e9f2f19ef244fed290da3983b319f2c39 100644
--- a/src/main/java/io/papermc/paper/adventure/PaperAdventure.java
+++ b/src/main/java/io/papermc/paper/adventure/PaperAdventure.java
@@ -111,7 +111,7 @@ public final class PaperAdventure {
 
     public static final ANSIComponentSerializer ANSI_SERIALIZER = ANSIComponentSerializer.builder().flattener(FLATTENER).build();
 
-    private static final Codec<CompoundTag, String, IOException, IOException> NBT_CODEC = new Codec<CompoundTag, String, IOException, IOException>() {
+    public static final Codec<CompoundTag, String, IOException, IOException> NBT_CODEC = new Codec<CompoundTag, String, IOException, IOException>() {
         @Override
         public @NotNull CompoundTag decode(final @NotNull String encoded) throws IOException {
             try {