package net.minecraft.util.random;

import com.mojang.logging.LogUtils;
import com.mojang.serialization.Codec;
import com.mojang.serialization.MapCodec;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import io.netty.buffer.ByteBuf;
import java.util.function.BiFunction;
import java.util.function.Function;
import net.minecraft.SharedConstants;
import net.minecraft.network.codec.ByteBufCodecs;
import net.minecraft.network.codec.StreamCodec;
import net.minecraft.util.ExtraCodecs;
import net.minecraft.util.Util;
import org.slf4j.Logger;

public record Weighted<T>(T value, int weight) {
	private static final Logger LOGGER = LogUtils.getLogger();

	public Weighted {
		if (weight < 0) {
			throw (IllegalArgumentException)Util.pauseInIde(new IllegalArgumentException("Weight should be >= 0"));
		}

		if (weight == 0 && SharedConstants.IS_RUNNING_IN_IDE) {
			LOGGER.warn("Found 0 weight, make sure this is intentional!");
		}
	}

	public static <E> Codec<Weighted<E>> codec(final Codec<E> elementCodec) {
		return codec(elementCodec.fieldOf("data"));
	}

	public static <E> Codec<Weighted<E>> codec(final MapCodec<E> elementCodec) {
		return RecordCodecBuilder.create(
			i -> i.group(elementCodec.forGetter((Function<Weighted<E>, E>)(Weighted::value)), ExtraCodecs.NON_NEGATIVE_INT.fieldOf("weight").forGetter(Weighted::weight))
				.apply(i, (BiFunction<E, Integer, Weighted<E>>)(Weighted::new))
		);
	}

	public static <B extends ByteBuf, T> StreamCodec<B, Weighted<T>> streamCodec(final StreamCodec<B, T> valueCodec) {
		return StreamCodec.composite(valueCodec, Weighted::value, ByteBufCodecs.VAR_INT, Weighted::weight, Weighted::new);
	}

	public <U> Weighted<U> map(final Function<T, U> function) {
		return new Weighted<>(function.apply(this.value()), this.weight);
	}
}