package net.minecraft.world.level.storage.loot.providers.number;

import com.mojang.serialization.MapCodec;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import net.minecraft.util.RandomSource;
import net.minecraft.world.level.storage.loot.LootContext;
import net.minecraft.world.level.storage.loot.Validatable;
import net.minecraft.world.level.storage.loot.ValidationContext;

public record BinomialDistributionGenerator(NumberProvider n, NumberProvider p) implements NumberProvider {
	public static final MapCodec<BinomialDistributionGenerator> MAP_CODEC = RecordCodecBuilder.mapCodec(
		i -> i.group(
				NumberProviders.CODEC.fieldOf("n").forGetter(BinomialDistributionGenerator::n),
				NumberProviders.CODEC.fieldOf("p").forGetter(BinomialDistributionGenerator::p)
			)
			.apply(i, BinomialDistributionGenerator::new)
	);

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

	@Override
	public int getInt(final LootContext context) {
		int n = this.n.getInt(context);
		float p = this.p.getFloat(context);
		RandomSource random = context.getRandom();
		int result = 0;

		for (int i = 0; i < n; i++) {
			if (random.nextFloat() < p) {
				result++;
			}
		}

		return result;
	}

	@Override
	public float getFloat(final LootContext context) {
		return this.getInt(context);
	}

	public static BinomialDistributionGenerator binomial(final int n, final float p) {
		return new BinomialDistributionGenerator(ConstantValue.exactly(n), ConstantValue.exactly(p));
	}

	@Override
	public void validate(final ValidationContext context) {
		NumberProvider.super.validate(context);
		Validatable.validate(context, "n", this.n);
		Validatable.validate(context, "p", this.p);
	}
}