package net.minecraft.world.level.storage.loot.entries;

import com.mojang.datafixers.util.Either;
import com.mojang.serialization.Codec;
import com.mojang.serialization.MapCodec;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import java.util.List;
import java.util.function.Consumer;
import net.minecraft.core.Holder;
import net.minecraft.resources.ResourceKey;
import net.minecraft.util.ProblemReporter;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.level.storage.loot.LootContext;
import net.minecraft.world.level.storage.loot.LootTable;
import net.minecraft.world.level.storage.loot.Validatable;
import net.minecraft.world.level.storage.loot.ValidationContext;
import net.minecraft.world.level.storage.loot.functions.LootItemFunction;
import net.minecraft.world.level.storage.loot.predicates.LootItemCondition;

public class NestedLootTable extends LootPoolSingletonContainer {
	public static final MapCodec<NestedLootTable> MAP_CODEC = RecordCodecBuilder.mapCodec(
		i -> i.group(Codec.either(LootTable.KEY_CODEC, LootTable.DIRECT_CODEC).fieldOf("value").forGetter(e -> e.contents))
			.<int, int, List<LootItemCondition>, List<LootItemFunction>>and(singletonFields(i))
			.apply(i, NestedLootTable::new)
	);
	public static final ProblemReporter.PathElement INLINE_LOOT_TABLE_PATH_ELEMENT = new ProblemReporter.PathElement() {
		@Override
		public String get() {
			return "->{inline}";
		}
	};
	private final Either<ResourceKey<LootTable>, LootTable> contents;

	private NestedLootTable(
		final Either<ResourceKey<LootTable>, LootTable> contents,
		final int weight,
		final int quality,
		final List<LootItemCondition> conditions,
		final List<LootItemFunction> functions
	) {
		super(weight, quality, conditions, functions);
		this.contents = contents;
	}

	@Override
	public MapCodec<NestedLootTable> codec() {
		return MAP_CODEC;
	}

	@Override
	public void createItemStack(final Consumer<ItemStack> output, final LootContext context) {
		this.contents
			.<LootTable>map(name -> (LootTable)context.getResolver().get(name).map(Holder::value).orElse(LootTable.EMPTY), table -> table)
			.getRandomItemsRaw(context, output);
	}

	@Override
	public void validate(final ValidationContext context) {
		super.validate(context);
		this.contents
			.ifLeft(id -> Validatable.validateReference(context, id))
			.ifRight(lootTable -> lootTable.validate(context.forChild(INLINE_LOOT_TABLE_PATH_ELEMENT)));
	}

	public static LootPoolSingletonContainer.Builder<?> lootTableReference(final ResourceKey<LootTable> name) {
		return simpleBuilder((weight, quality, conditions, functions) -> new NestedLootTable(Either.left(name), weight, quality, conditions, functions));
	}

	public static LootPoolSingletonContainer.Builder<?> inlineLootTable(final LootTable table) {
		return simpleBuilder((weight, quality, conditions, functions) -> new NestedLootTable(Either.right(table), weight, quality, conditions, functions));
	}
}