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.CommandBuildContext;
import net.minecraft.commands.CommandSourceStack;
import net.minecraft.commands.Commands;
import net.minecraft.commands.arguments.CompoundTagArgument;
import net.minecraft.commands.arguments.ResourceArgument;
import net.minecraft.commands.arguments.coordinates.Vec3Argument;
import net.minecraft.commands.synchronization.SuggestionProviders;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Holder;
import net.minecraft.core.registries.Registries;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.network.chat.Component;
import net.minecraft.server.level.ServerLevel;
import net.minecraft.world.Difficulty;
import net.minecraft.world.entity.Entity;
import net.minecraft.world.entity.EntitySpawnReason;
import net.minecraft.world.entity.EntityType;
import net.minecraft.world.entity.Mob;
import net.minecraft.world.level.Level;
import net.minecraft.world.phys.Vec3;

public class SummonCommand {
	private static final SimpleCommandExceptionType ERROR_FAILED = new SimpleCommandExceptionType(Component.translatable("commands.summon.failed"));
	private static final SimpleCommandExceptionType ERROR_FAILED_PEACEFUL = new SimpleCommandExceptionType(
		Component.translatable("commands.summon.failed.peaceful")
	);
	private static final SimpleCommandExceptionType ERROR_DUPLICATE_UUID = new SimpleCommandExceptionType(Component.translatable("commands.summon.failed.uuid"));
	private static final SimpleCommandExceptionType INVALID_POSITION = new SimpleCommandExceptionType(Component.translatable("commands.summon.invalidPosition"));

	public static void register(final CommandDispatcher<CommandSourceStack> dispatcher, final CommandBuildContext context) {
		dispatcher.register(
			Commands.literal("summon")
				.requires(Commands.hasPermission(Commands.LEVEL_GAMEMASTERS))
				.then(
					Commands.argument("entity", ResourceArgument.resource(context, Registries.ENTITY_TYPE))
						.suggests(SuggestionProviders.cast(SuggestionProviders.SUMMONABLE_ENTITIES))
						.executes(c -> spawnEntity(c.getSource(), ResourceArgument.getSummonableEntityType(c, "entity"), c.getSource().getPosition(), new CompoundTag(), true))
						.then(
							Commands.argument("pos", Vec3Argument.vec3())
								.executes(
									c -> spawnEntity(c.getSource(), ResourceArgument.getSummonableEntityType(c, "entity"), Vec3Argument.getVec3(c, "pos"), new CompoundTag(), true)
								)
								.then(
									Commands.argument("nbt", CompoundTagArgument.compoundTag())
										.executes(
											c -> spawnEntity(
												c.getSource(),
												ResourceArgument.getSummonableEntityType(c, "entity"),
												Vec3Argument.getVec3(c, "pos"),
												CompoundTagArgument.getCompoundTag(c, "nbt"),
												false
											)
										)
								)
						)
				)
		);
	}

	public static Entity createEntity(
		final CommandSourceStack source, final Holder.Reference<EntityType<?>> type, final Vec3 pos, final CompoundTag nbt, final boolean finalize
	) throws CommandSyntaxException {
		BlockPos blockPos = BlockPos.containing(pos);
		if (!Level.isInSpawnableBounds(blockPos)) {
			throw INVALID_POSITION.create();
		} else if (source.getLevel().getDifficulty() == Difficulty.PEACEFUL && !type.value().isAllowedInPeaceful()) {
			throw ERROR_FAILED_PEACEFUL.create();
		} else {
			CompoundTag entityTag = nbt.copy();
			entityTag.putString("id", type.key().identifier().toString());
			ServerLevel level = source.getLevel();
			Entity entity = EntityType.loadEntityRecursive(entityTag, level, EntitySpawnReason.COMMAND, e -> {
				e.snapTo(pos.x, pos.y, pos.z, e.getYRot(), e.getXRot());
				return e;
			});
			if (entity == null) {
				throw ERROR_FAILED.create();
			} else {
				if (finalize && entity instanceof Mob mob) {
					mob.finalizeSpawn(source.getLevel(), source.getLevel().getCurrentDifficultyAt(entity.blockPosition()), EntitySpawnReason.COMMAND, null);
				}

				if (!level.tryAddFreshEntityWithPassengers(entity)) {
					throw ERROR_DUPLICATE_UUID.create();
				} else {
					return entity;
				}
			}
		}
	}

	private static int spawnEntity(
		final CommandSourceStack source, final Holder.Reference<EntityType<?>> type, final Vec3 pos, final CompoundTag nbt, final boolean finalize
	) throws CommandSyntaxException {
		Entity entity = createEntity(source, type, pos, nbt, finalize);
		source.sendSuccess(() -> Component.translatable("commands.summon.success", entity.getDisplayName()), true);
		return 1;
	}
}