package net.minecraft.commands.arguments;

import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
import net.minecraft.network.FriendlyByteBuf;
import net.minecraft.network.chat.MessageSignature;
import net.minecraft.network.chat.SignableCommand;
import org.jspecify.annotations.Nullable;

public record ArgumentSignatures(List<ArgumentSignatures.Entry> entries) {
	public static final ArgumentSignatures EMPTY = new ArgumentSignatures(List.of());
	private static final int MAX_ARGUMENT_COUNT = 8;
	private static final int MAX_ARGUMENT_NAME_LENGTH = 16;

	public ArgumentSignatures(final FriendlyByteBuf input) {
		this(input.readCollection(FriendlyByteBuf.limitValue(ArrayList::new, 8), ArgumentSignatures.Entry::new));
	}

	public void write(final FriendlyByteBuf output) {
		output.writeCollection(this.entries, (out, entry) -> entry.write(out));
	}

	public static ArgumentSignatures signCommand(final SignableCommand<?> command, final ArgumentSignatures.Signer signer) {
		List<ArgumentSignatures.Entry> entries = command.arguments().stream().map(argument -> {
			MessageSignature signature = signer.sign(argument.value());
			return signature != null ? new ArgumentSignatures.Entry(argument.name(), signature) : null;
		}).filter(Objects::nonNull).toList();
		return new ArgumentSignatures(entries);
	}

	public record Entry(String name, MessageSignature signature) {
		public Entry(final FriendlyByteBuf input) {
			this(input.readUtf(16), MessageSignature.read(input));
		}

		public void write(final FriendlyByteBuf output) {
			output.writeUtf(this.name, 16);
			MessageSignature.write(output, this.signature);
		}
	}

	@FunctionalInterface
	public interface Signer {
		@Nullable
		MessageSignature sign(String content);
	}
}