package net.minecraft.server.level;

import com.mojang.logging.LogUtils;
import java.util.Collections;
import java.util.List;
import java.util.Locale;
import java.util.concurrent.atomic.AtomicLong;
import java.util.function.Predicate;
import java.util.function.Supplier;
import net.minecraft.CrashReport;
import net.minecraft.CrashReportCategory;
import net.minecraft.CrashReportDetail;
import net.minecraft.ReportedException;
import net.minecraft.Util;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.core.Holder;
import net.minecraft.core.RegistryAccess;
import net.minecraft.core.SectionPos;
import net.minecraft.core.particles.ParticleOptions;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.resources.ResourceLocation;
import net.minecraft.server.MinecraftServer;
import net.minecraft.sounds.SoundEvent;
import net.minecraft.sounds.SoundSource;
import net.minecraft.util.RandomSource;
import net.minecraft.util.StaticCache2D;
import net.minecraft.world.DifficultyInstance;
import net.minecraft.world.entity.Entity;
import net.minecraft.world.entity.player.Player;
import net.minecraft.world.flag.FeatureFlagSet;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.level.ChunkPos;
import net.minecraft.world.level.LevelHeightAccessor;
import net.minecraft.world.level.WorldGenLevel;
import net.minecraft.world.level.biome.Biome;
import net.minecraft.world.level.biome.BiomeManager;
import net.minecraft.world.level.block.Block;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.EntityBlock;
import net.minecraft.world.level.block.entity.BlockEntity;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.border.WorldBorder;
import net.minecraft.world.level.chunk.ChunkAccess;
import net.minecraft.world.level.chunk.ChunkSource;
import net.minecraft.world.level.chunk.status.ChunkStatus;
import net.minecraft.world.level.chunk.status.ChunkStep;
import net.minecraft.world.level.chunk.status.ChunkType;
import net.minecraft.world.level.dimension.DimensionType;
import net.minecraft.world.level.entity.EntityTypeTest;
import net.minecraft.world.level.gameevent.GameEvent;
import net.minecraft.world.level.gameevent.GameEvent.Context;
import net.minecraft.world.level.levelgen.Heightmap;
import net.minecraft.world.level.lighting.LevelLightEngine;
import net.minecraft.world.level.material.Fluid;
import net.minecraft.world.level.material.FluidState;
import net.minecraft.world.level.storage.LevelData;
import net.minecraft.world.phys.AABB;
import net.minecraft.world.phys.Vec3;
import net.minecraft.world.ticks.LevelTickAccess;
import net.minecraft.world.ticks.WorldGenTickAccess;
import org.jetbrains.annotations.Nullable;
import org.slf4j.Logger;

public class WorldGenRegion implements WorldGenLevel {
	private static final Logger LOGGER = LogUtils.getLogger();
	private final StaticCache2D<GenerationChunkHolder> cache;
	private final ChunkAccess center;
	private final ServerLevel level;
	private final long seed;
	private final LevelData levelData;
	private final RandomSource random;
	private final DimensionType dimensionType;
	private final WorldGenTickAccess<Block> blockTicks = new WorldGenTickAccess<>(blockPos -> this.getChunk(blockPos).getBlockTicks());
	private final WorldGenTickAccess<Fluid> fluidTicks = new WorldGenTickAccess<>(blockPos -> this.getChunk(blockPos).getFluidTicks());
	private final BiomeManager biomeManager;
	private final ChunkStep generatingStep;
	@Nullable
	private Supplier<String> currentlyGenerating;
	private final AtomicLong subTickCount = new AtomicLong();
	private static final ResourceLocation WORLDGEN_REGION_RANDOM = ResourceLocation.withDefaultNamespace("worldgen_region_random");

	public WorldGenRegion(ServerLevel level, StaticCache2D<GenerationChunkHolder> cache, ChunkStep generatingStep, ChunkAccess center) {
		this.generatingStep = generatingStep;
		this.cache = cache;
		this.center = center;
		this.level = level;
		this.seed = level.getSeed();
		this.levelData = level.getLevelData();
		this.random = level.getChunkSource().randomState().getOrCreateRandomFactory(WORLDGEN_REGION_RANDOM).at(this.center.getPos().getWorldPosition());
		this.dimensionType = level.dimensionType();
		this.biomeManager = new BiomeManager(this, BiomeManager.obfuscateSeed(this.seed));
	}

	public boolean isOldChunkAround(ChunkPos pos, int radius) {
		return this.level.getChunkSource().chunkMap.isOldChunkAround(pos, radius);
	}

	public ChunkPos getCenter() {
		return this.center.getPos();
	}

	@Override
	public void setCurrentlyGenerating(@Nullable Supplier<String> currentlyGenerating) {
		this.currentlyGenerating = currentlyGenerating;
	}

	@Override
	public ChunkAccess getChunk(int chunkX, int chunkZ) {
		return this.getChunk(chunkX, chunkZ, ChunkStatus.EMPTY);
	}

	@Nullable
	@Override
	public ChunkAccess getChunk(int x, int z, ChunkStatus chunkStatus, boolean requireChunk) {
		int i = this.center.getPos().getChessboardDistance(x, z);
		ChunkStatus chunkStatus2 = i >= this.generatingStep.directDependencies().size() ? null : this.generatingStep.directDependencies().get(i);
		GenerationChunkHolder generationChunkHolder;
		if (chunkStatus2 != null) {
			generationChunkHolder = this.cache.get(x, z);
			if (chunkStatus.isOrBefore(chunkStatus2)) {
				ChunkAccess chunkAccess = generationChunkHolder.getChunkIfPresentUnchecked(chunkStatus2);
				if (chunkAccess != null) {
					return chunkAccess;
				}
			}
		} else {
			generationChunkHolder = null;
		}

		CrashReport crashReport = CrashReport.forThrowable(
			new IllegalStateException("Requested chunk unavailable during world generation"), "Exception generating new chunk"
		);
		CrashReportCategory crashReportCategory = crashReport.addCategory("Chunk request details");
		crashReportCategory.setDetail("Requested chunk", String.format(Locale.ROOT, "%d, %d", x, z));
		crashReportCategory.setDetail("Generating status", (CrashReportDetail<String>)(() -> this.generatingStep.targetStatus().getName()));
		crashReportCategory.setDetail("Requested status", chunkStatus::getName);
		crashReportCategory.setDetail(
			"Actual status",
			(CrashReportDetail<String>)(() -> generationChunkHolder == null ? "[out of cache bounds]" : generationChunkHolder.getPersistedStatus().getName())
		);
		crashReportCategory.setDetail("Maximum allowed status", (CrashReportDetail<String>)(() -> chunkStatus2 == null ? "null" : chunkStatus2.getName()));
		crashReportCategory.setDetail("Dependencies", this.generatingStep.directDependencies()::toString);
		crashReportCategory.setDetail("Requested distance", i);
		crashReportCategory.setDetail("Generating chunk", this.center.getPos()::toString);
		throw new ReportedException(crashReport);
	}

	@Override
	public boolean hasChunk(int chunkX, int chunkZ) {
		int i = this.center.getPos().getChessboardDistance(chunkX, chunkZ);
		return i < this.generatingStep.directDependencies().size();
	}

	@Override
	public BlockState getBlockState(BlockPos pos) {
		return this.getChunk(SectionPos.blockToSectionCoord(pos.getX()), SectionPos.blockToSectionCoord(pos.getZ())).getBlockState(pos);
	}

	@Override
	public FluidState getFluidState(BlockPos pos) {
		return this.getChunk(pos).getFluidState(pos);
	}

	@Nullable
	@Override
	public Player getNearestPlayer(double x, double y, double z, double distance, Predicate<Entity> predicate) {
		return null;
	}

	@Override
	public int getSkyDarken() {
		return 0;
	}

	@Override
	public BiomeManager getBiomeManager() {
		return this.biomeManager;
	}

	@Override
	public Holder<Biome> getUncachedNoiseBiome(int x, int y, int z) {
		return this.level.getUncachedNoiseBiome(x, y, z);
	}

	@Override
	public float getShade(Direction direction, boolean shade) {
		return 1.0F;
	}

	@Override
	public LevelLightEngine getLightEngine() {
		return this.level.getLightEngine();
	}

	@Override
	public boolean destroyBlock(BlockPos pos, boolean dropBlock, @Nullable Entity entity, int recursionLeft) {
		BlockState blockState = this.getBlockState(pos);
		if (blockState.isAir()) {
			return false;
		} else {
			if (dropBlock) {
				BlockEntity blockEntity = blockState.hasBlockEntity() ? this.getBlockEntity(pos) : null;
				Block.dropResources(blockState, this.level, pos, blockEntity, entity, ItemStack.EMPTY);
			}

			return this.setBlock(pos, Blocks.AIR.defaultBlockState(), 3, recursionLeft);
		}
	}

	@Nullable
	@Override
	public BlockEntity getBlockEntity(BlockPos pos) {
		ChunkAccess chunkAccess = this.getChunk(pos);
		BlockEntity blockEntity = chunkAccess.getBlockEntity(pos);
		if (blockEntity != null) {
			return blockEntity;
		} else {
			CompoundTag compoundTag = chunkAccess.getBlockEntityNbt(pos);
			BlockState blockState = chunkAccess.getBlockState(pos);
			if (compoundTag != null) {
				if ("DUMMY".equals(compoundTag.getStringOr("id", ""))) {
					if (!blockState.hasBlockEntity()) {
						return null;
					}

					blockEntity = ((EntityBlock)blockState.getBlock()).newBlockEntity(pos, blockState);
				} else {
					blockEntity = BlockEntity.loadStatic(pos, blockState, compoundTag, this.level.registryAccess());
				}

				if (blockEntity != null) {
					chunkAccess.setBlockEntity(blockEntity);
					return blockEntity;
				}
			}

			if (blockState.hasBlockEntity()) {
				LOGGER.warn("Tried to access a block entity before it was created. {}", pos);
			}

			return null;
		}
	}

	@Override
	public boolean ensureCanWrite(BlockPos pos) {
		int i = SectionPos.blockToSectionCoord(pos.getX());
		int j = SectionPos.blockToSectionCoord(pos.getZ());
		ChunkPos chunkPos = this.getCenter();
		int k = Math.abs(chunkPos.x - i);
		int l = Math.abs(chunkPos.z - j);
		if (k <= this.generatingStep.blockStateWriteRadius() && l <= this.generatingStep.blockStateWriteRadius()) {
			if (this.center.isUpgrading()) {
				LevelHeightAccessor levelHeightAccessor = this.center.getHeightAccessorForGeneration();
				if (levelHeightAccessor.isOutsideBuildHeight(pos.getY())) {
					return false;
				}
			}

			return true;
		} else {
			Util.logAndPauseIfInIde(
				"Detected setBlock in a far chunk ["
					+ i
					+ ", "
					+ j
					+ "], pos: "
					+ pos
					+ ", status: "
					+ this.generatingStep.targetStatus()
					+ (this.currentlyGenerating == null ? "" : ", currently generating: " + (String)this.currentlyGenerating.get())
			);
			return false;
		}
	}

	@Override
	public boolean setBlock(BlockPos pos, BlockState state, int flags, int recursionLeft) {
		if (!this.ensureCanWrite(pos)) {
			return false;
		} else {
			ChunkAccess chunkAccess = this.getChunk(pos);
			BlockState blockState = chunkAccess.setBlockState(pos, state, flags);
			if (blockState != null) {
				this.level.updatePOIOnBlockStateChange(pos, blockState, state);
			}

			if (state.hasBlockEntity()) {
				if (chunkAccess.getPersistedStatus().getChunkType() == ChunkType.LEVELCHUNK) {
					BlockEntity blockEntity = ((EntityBlock)state.getBlock()).newBlockEntity(pos, state);
					if (blockEntity != null) {
						chunkAccess.setBlockEntity(blockEntity);
					} else {
						chunkAccess.removeBlockEntity(pos);
					}
				} else {
					CompoundTag compoundTag = new CompoundTag();
					compoundTag.putInt("x", pos.getX());
					compoundTag.putInt("y", pos.getY());
					compoundTag.putInt("z", pos.getZ());
					compoundTag.putString("id", "DUMMY");
					chunkAccess.setBlockEntityNbt(compoundTag);
				}
			} else if (blockState != null && blockState.hasBlockEntity()) {
				chunkAccess.removeBlockEntity(pos);
			}

			if (state.hasPostProcess(this, pos) && (flags & 16) == 0) {
				this.markPosForPostprocessing(pos);
			}

			return true;
		}
	}

	private void markPosForPostprocessing(BlockPos pos) {
		this.getChunk(pos).markPosForPostprocessing(pos);
	}

	@Override
	public boolean addFreshEntity(Entity entity) {
		int i = SectionPos.blockToSectionCoord(entity.getBlockX());
		int j = SectionPos.blockToSectionCoord(entity.getBlockZ());
		this.getChunk(i, j).addEntity(entity);
		return true;
	}

	@Override
	public boolean removeBlock(BlockPos pos, boolean isMoving) {
		return this.setBlock(pos, Blocks.AIR.defaultBlockState(), 3);
	}

	@Override
	public WorldBorder getWorldBorder() {
		return this.level.getWorldBorder();
	}

	@Override
	public boolean isClientSide() {
		return false;
	}

	@Deprecated
	@Override
	public ServerLevel getLevel() {
		return this.level;
	}

	@Override
	public RegistryAccess registryAccess() {
		return this.level.registryAccess();
	}

	@Override
	public FeatureFlagSet enabledFeatures() {
		return this.level.enabledFeatures();
	}

	@Override
	public LevelData getLevelData() {
		return this.levelData;
	}

	@Override
	public DifficultyInstance getCurrentDifficultyAt(BlockPos pos) {
		if (!this.hasChunk(SectionPos.blockToSectionCoord(pos.getX()), SectionPos.blockToSectionCoord(pos.getZ()))) {
			throw new RuntimeException("We are asking a region for a chunk out of bound");
		} else {
			return new DifficultyInstance(this.level.getDifficulty(), this.level.getDayTime(), 0L, this.level.getMoonBrightness());
		}
	}

	@Nullable
	@Override
	public MinecraftServer getServer() {
		return this.level.getServer();
	}

	@Override
	public ChunkSource getChunkSource() {
		return this.level.getChunkSource();
	}

	@Override
	public long getSeed() {
		return this.seed;
	}

	@Override
	public LevelTickAccess<Block> getBlockTicks() {
		return this.blockTicks;
	}

	@Override
	public LevelTickAccess<Fluid> getFluidTicks() {
		return this.fluidTicks;
	}

	@Override
	public int getSeaLevel() {
		return this.level.getSeaLevel();
	}

	@Override
	public RandomSource getRandom() {
		return this.random;
	}

	@Override
	public int getHeight(Heightmap.Types heightmapType, int x, int z) {
		return this.getChunk(SectionPos.blockToSectionCoord(x), SectionPos.blockToSectionCoord(z)).getHeight(heightmapType, x & 15, z & 15) + 1;
	}

	@Override
	public void playSound(@Nullable Entity entity, BlockPos pos, SoundEvent sound, SoundSource source, float volume, float pitch) {
	}

	@Override
	public void addParticle(ParticleOptions particle, double x, double y, double z, double xSpeed, double ySpeed, double zSpeed) {
	}

	@Override
	public void levelEvent(@Nullable Entity entity, int type, BlockPos pos, int data) {
	}

	@Override
	public void gameEvent(Holder<GameEvent> gameEvent, Vec3 pos, Context context) {
	}

	@Override
	public DimensionType dimensionType() {
		return this.dimensionType;
	}

	@Override
	public boolean isStateAtPosition(BlockPos pos, Predicate<BlockState> state) {
		return state.test(this.getBlockState(pos));
	}

	@Override
	public boolean isFluidAtPosition(BlockPos pos, Predicate<FluidState> predicate) {
		return predicate.test(this.getFluidState(pos));
	}

	@Override
	public <T extends Entity> List<T> getEntities(EntityTypeTest<Entity, T> entityTypeTest, AABB bounds, Predicate<? super T> predicate) {
		return Collections.emptyList();
	}

	@Override
	public List<Entity> getEntities(@Nullable Entity entity, AABB area, @Nullable Predicate<? super Entity> predicate) {
		return Collections.emptyList();
	}

	@Override
	public List<Player> players() {
		return Collections.emptyList();
	}

	@Override
	public int getMinY() {
		return this.level.getMinY();
	}

	@Override
	public int getHeight() {
		return this.level.getHeight();
	}

	@Override
	public long nextSubTickCount() {
		return this.subTickCount.getAndIncrement();
	}
}