package net.minecraft.world.level.levelgen.structure;

import com.mojang.serialization.Codec;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import java.util.List;
import net.minecraft.core.Holder;
import net.minecraft.core.registries.Registries;
import net.minecraft.resources.RegistryFileCodec;
import net.minecraft.util.ExtraCodecs;
import net.minecraft.world.level.levelgen.structure.placement.StructurePlacement;

public record StructureSet(List<StructureSet.StructureSelectionEntry> structures, StructurePlacement placement) {
	public static final Codec<StructureSet> DIRECT_CODEC = RecordCodecBuilder.create(
		instance -> instance.group(
				StructureSet.StructureSelectionEntry.CODEC.listOf().fieldOf("structures").forGetter(StructureSet::structures),
				StructurePlacement.CODEC.fieldOf("placement").forGetter(StructureSet::placement)
			)
			.apply(instance, StructureSet::new)
	);
	public static final Codec<Holder<StructureSet>> CODEC = RegistryFileCodec.create(Registries.STRUCTURE_SET, DIRECT_CODEC);

	public StructureSet(Holder<Structure> structure, StructurePlacement placement) {
		this(List.of(new StructureSet.StructureSelectionEntry(structure, 1)), placement);
	}

	public static StructureSet.StructureSelectionEntry entry(Holder<Structure> structure, int weight) {
		return new StructureSet.StructureSelectionEntry(structure, weight);
	}

	public static StructureSet.StructureSelectionEntry entry(Holder<Structure> structure) {
		return new StructureSet.StructureSelectionEntry(structure, 1);
	}

	public record StructureSelectionEntry(Holder<Structure> structure, int weight) {
		public static final Codec<StructureSet.StructureSelectionEntry> CODEC = RecordCodecBuilder.create(
			instance -> instance.group(
					Structure.CODEC.fieldOf("structure").forGetter(StructureSet.StructureSelectionEntry::structure),
					ExtraCodecs.POSITIVE_INT.fieldOf("weight").forGetter(StructureSet.StructureSelectionEntry::weight)
				)
				.apply(instance, StructureSet.StructureSelectionEntry::new)
		);
	}
}