src/game/java/net/minecraft/server/commands/GameRuleCommand.java

package net.minecraft.server.commands;

import com.mojang.brigadier.CommandDispatcher;
import com.mojang.brigadier.builder.LiteralArgumentBuilder;
import com.mojang.brigadier.context.CommandContext;
import net.minecraft.commands.CommandBuildContext;
import net.minecraft.commands.CommandSourceStack;
import net.minecraft.commands.Commands;
import net.minecraft.network.chat.Component;
import net.minecraft.world.level.GameRules;

public class GameRuleCommand {
    public static void register(CommandDispatcher<CommandSourceStack> p_137745_, CommandBuildContext p_368575_) {
        final LiteralArgumentBuilder<CommandSourceStack> literalargumentbuilder = Commands.literal("gamerule").requires(p_137750_ -> p_137750_.hasPermission(2));
        new GameRules(p_368575_.enabledFeatures())
            .visitGameRuleTypes(
                new GameRules.GameRuleTypeVisitor() {
                    @Override
                    public <T extends GameRules.Value<T>> void visit(GameRules.Key<T> p_137764_, GameRules.Type<T> p_137765_) {
                        LiteralArgumentBuilder<CommandSourceStack> literalargumentbuilder1 = Commands.literal(p_137764_.getId());
                        literalargumentbuilder.then(
                            literalargumentbuilder1.executes(p_137771_ -> GameRuleCommand.queryRule(p_137771_.getSource(), p_137764_))
                                .then(p_137765_.createArgument("value").executes(p_137768_ -> GameRuleCommand.setRule(p_137768_, p_137764_)))
                        );
                    }
                }
            );
        p_137745_.register(literalargumentbuilder);
    }

    static <T extends GameRules.Value<T>> int setRule(CommandContext<CommandSourceStack> p_137755_, GameRules.Key<T> p_137756_) {
        CommandSourceStack commandsourcestack = p_137755_.getSource();
        T t = commandsourcestack.getServer().getGameRules().getRule(p_137756_);
        t.setFromArgument(p_137755_, "value");
        commandsourcestack.sendSuccess(() -> Component.translatable("commands.gamerule.set", p_137756_.getId(), t.toString()), true);
        return t.getCommandResult();
    }

    static <T extends GameRules.Value<T>> int queryRule(CommandSourceStack p_137758_, GameRules.Key<T> p_137759_) {
        T t = p_137758_.getServer().getGameRules().getRule(p_137759_);
        p_137758_.sendSuccess(() -> Component.translatable("commands.gamerule.query", p_137759_.getId(), t.toString()), false);
        return t.getCommandResult();
    }
}