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

import com.mojang.serialization.DataResult;
import java.util.List;
import java.util.Optional;
import java.util.function.Function;
import net.minecraft.resources.ResourceKey;
import net.minecraft.util.ProblemReporter;
import net.minecraft.util.context.ContextKeySet;

public interface Validatable {
	void validate(ValidationContext context);

	static void validate(final ValidationContext context, final String name, final Validatable v) {
		v.validate(context.forField(name));
	}

	static void validate(final ValidationContext context, final String name, final Optional<? extends Validatable> optional) {
		optional.ifPresent(v -> v.validate(context.forField(name)));
	}

	static void validate(final ValidationContext context, final String name, final List<? extends Validatable> list) {
		for (int i = 0; i < list.size(); i++) {
			((Validatable)list.get(i)).validate(context.forIndexedField(name, i));
		}
	}

	static void validate(final ValidationContext context, final List<? extends Validatable> list) {
		for (int i = 0; i < list.size(); i++) {
			((Validatable)list.get(i)).validate(context.forChild(new ProblemReporter.IndexedPathElement(i)));
		}
	}

	static <T extends Validatable> void validateReference(final ValidationContext context, final ResourceKey<T> id) {
		if (!context.allowsReferences()) {
			context.reportProblem(new ValidationContext.ReferenceNotAllowedProblem(id));
		} else if (context.hasVisitedElement(id)) {
			context.reportProblem(new ValidationContext.RecursiveReferenceProblem(id));
		} else {
			context.resolver()
				.get(id)
				.ifPresentOrElse(
					element -> ((Validatable)element.value()).validate(context.enterElement(new ProblemReporter.ElementReferencePathElement(id), id)),
					() -> context.reportProblem(new ValidationContext.MissingReferenceProblem(id))
				);
		}
	}

	static <T extends Validatable> Function<T, DataResult<T>> validatorForContext(final ContextKeySet params) {
		return v -> {
			ProblemReporter.Collector problemCollector = new ProblemReporter.Collector();
			ValidationContext validationContext = new ValidationContext(problemCollector, params);
			v.validate(validationContext);
			return !problemCollector.isEmpty() ? DataResult.error(() -> "Validation error: " + problemCollector.getReport()) : DataResult.success(v);
		};
	}

	static <T extends Validatable> Function<List<T>, DataResult<List<T>>> listValidatorForContext(final ContextKeySet params) {
		return v -> {
			ProblemReporter.Collector problemCollector = new ProblemReporter.Collector();
			ValidationContext validationContext = new ValidationContext(problemCollector, params);
			validate(validationContext, v);
			return !problemCollector.isEmpty() ? DataResult.error(() -> "Validation error: " + problemCollector.getReport()) : DataResult.success(v);
		};
	}
}