package net.minecraft.server.commands;

import com.mojang.brigadier.CommandDispatcher;
import com.mojang.brigadier.exceptions.CommandSyntaxException;
import com.mojang.brigadier.exceptions.SimpleCommandExceptionType;
import net.minecraft.commands.CommandSourceStack;
import net.minecraft.commands.Commands;
import net.minecraft.commands.arguments.coordinates.BlockPosArgument;
import net.minecraft.core.BlockPos;
import net.minecraft.network.chat.Component;
import net.minecraft.world.entity.Mob;
import net.minecraft.world.entity.ai.navigation.GroundPathNavigation;
import net.minecraft.world.entity.ai.navigation.PathNavigation;
import net.minecraft.world.level.pathfinder.Path;

public class DebugPathCommand {
	private static final SimpleCommandExceptionType ERROR_NOT_MOB = new SimpleCommandExceptionType(Component.literal("Source is not a mob"));
	private static final SimpleCommandExceptionType ERROR_NO_PATH = new SimpleCommandExceptionType(Component.literal("Path not found"));
	private static final SimpleCommandExceptionType ERROR_NOT_COMPLETE = new SimpleCommandExceptionType(Component.literal("Target not reached"));

	public static void register(final CommandDispatcher<CommandSourceStack> dispatcher) {
		dispatcher.register(
			Commands.literal("debugpath")
				.requires(Commands.hasPermission(Commands.LEVEL_GAMEMASTERS))
				.then(Commands.argument("to", BlockPosArgument.blockPos()).executes(c -> fillBlocks(c.getSource(), BlockPosArgument.getLoadedBlockPos(c, "to"))))
		);
	}

	private static int fillBlocks(final CommandSourceStack source, final BlockPos target) throws CommandSyntaxException {
		if (source.getEntity() instanceof Mob mob) {
			PathNavigation pathNavigation = new GroundPathNavigation(mob, source.getLevel());
			Path path = pathNavigation.createPath(target, 0);
			if (path == null) {
				throw ERROR_NO_PATH.create();
			} else if (!path.canReach()) {
				throw ERROR_NOT_COMPLETE.create();
			} else {
				source.sendSuccess(() -> Component.literal("Made path"), true);
				return 1;
			}
		} else {
			throw ERROR_NOT_MOB.create();
		}
	}
}