package net.minecraft.world.level.material;

import com.google.common.collect.Maps;
import com.mojang.datafixers.util.Pair;
import it.unimi.dsi.fastutil.objects.Object2ByteLinkedOpenHashMap;
import it.unimi.dsi.fastutil.shorts.Short2BooleanFunction;
import it.unimi.dsi.fastutil.shorts.Short2BooleanMap;
import it.unimi.dsi.fastutil.shorts.Short2BooleanOpenHashMap;
import it.unimi.dsi.fastutil.shorts.Short2ObjectFunction;
import it.unimi.dsi.fastutil.shorts.Short2ObjectMap;
import it.unimi.dsi.fastutil.shorts.Short2ObjectOpenHashMap;
import java.util.Map;
import java.util.Map.Entry;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.tags.BlockTags;
import net.minecraft.world.level.BlockGetter;
import net.minecraft.world.level.Level;
import net.minecraft.world.level.LevelAccessor;
import net.minecraft.world.level.LevelReader;
import net.minecraft.world.level.block.Block;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.DoorBlock;
import net.minecraft.world.level.block.IceBlock;
import net.minecraft.world.level.block.LiquidBlockContainer;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.block.state.StateDefinition;
import net.minecraft.world.level.block.state.properties.BlockStateProperties;
import net.minecraft.world.level.block.state.properties.BooleanProperty;
import net.minecraft.world.level.block.state.properties.IntegerProperty;
import net.minecraft.world.phys.Vec3;
import net.minecraft.world.phys.shapes.Shapes;
import net.minecraft.world.phys.shapes.VoxelShape;

public abstract class FlowingFluid extends Fluid {
	public static final BooleanProperty FALLING = BlockStateProperties.FALLING;
	public static final IntegerProperty LEVEL = BlockStateProperties.LEVEL_FLOWING;
	private static final int CACHE_SIZE = 200;
	private static final ThreadLocal<Object2ByteLinkedOpenHashMap<Block.BlockStatePairKey>> OCCLUSION_CACHE = ThreadLocal.withInitial(() -> {
		Object2ByteLinkedOpenHashMap<Block.BlockStatePairKey> object2ByteLinkedOpenHashMap = new Object2ByteLinkedOpenHashMap<Block.BlockStatePairKey>(200) {
			@Override
			protected void rehash(int i) {
			}
		};
		object2ByteLinkedOpenHashMap.defaultReturnValue((byte)127);
		return object2ByteLinkedOpenHashMap;
	});
	private final Map<FluidState, VoxelShape> shapes = Maps.<FluidState, VoxelShape>newIdentityHashMap();

	@Override
	protected void createFluidStateDefinition(StateDefinition.Builder<Fluid, FluidState> builder) {
		builder.add(FALLING);
	}

	@Override
	public Vec3 getFlow(BlockGetter blockReader, BlockPos pos, FluidState fluidState) {
		double d = 0.0;
		double e = 0.0;
		BlockPos.MutableBlockPos mutableBlockPos = new BlockPos.MutableBlockPos();

		for (Direction direction : Direction.Plane.HORIZONTAL) {
			mutableBlockPos.setWithOffset(pos, direction);
			FluidState fluidState2 = blockReader.getFluidState(mutableBlockPos);
			if (this.affectsFlow(fluidState2)) {
				float f = fluidState2.getOwnHeight();
				float g = 0.0F;
				if (f == 0.0F) {
					if (!blockReader.getBlockState(mutableBlockPos).blocksMotion()) {
						BlockPos blockPos = mutableBlockPos.below();
						FluidState fluidState3 = blockReader.getFluidState(blockPos);
						if (this.affectsFlow(fluidState3)) {
							f = fluidState3.getOwnHeight();
							if (f > 0.0F) {
								g = fluidState.getOwnHeight() - (f - 0.8888889F);
							}
						}
					}
				} else if (f > 0.0F) {
					g = fluidState.getOwnHeight() - f;
				}

				if (g != 0.0F) {
					d += direction.getStepX() * g;
					e += direction.getStepZ() * g;
				}
			}
		}

		Vec3 vec3 = new Vec3(d, 0.0, e);
		if ((Boolean)fluidState.getValue(FALLING)) {
			for (Direction direction2 : Direction.Plane.HORIZONTAL) {
				mutableBlockPos.setWithOffset(pos, direction2);
				if (this.isSolidFace(blockReader, mutableBlockPos, direction2) || this.isSolidFace(blockReader, mutableBlockPos.above(), direction2)) {
					vec3 = vec3.normalize().add(0.0, -6.0, 0.0);
					break;
				}
			}
		}

		return vec3.normalize();
	}

	private boolean affectsFlow(FluidState state) {
		return state.isEmpty() || state.getType().isSame(this);
	}

	protected boolean isSolidFace(BlockGetter level, BlockPos neighborPos, Direction side) {
		BlockState blockState = level.getBlockState(neighborPos);
		FluidState fluidState = level.getFluidState(neighborPos);
		if (fluidState.getType().isSame(this)) {
			return false;
		} else if (side == Direction.UP) {
			return true;
		} else {
			return blockState.getBlock() instanceof IceBlock ? false : blockState.isFaceSturdy(level, neighborPos, side);
		}
	}

	protected void spread(Level level, BlockPos pos, FluidState state) {
		if (!state.isEmpty()) {
			BlockState blockState = level.getBlockState(pos);
			BlockPos blockPos = pos.below();
			BlockState blockState2 = level.getBlockState(blockPos);
			FluidState fluidState = this.getNewLiquid(level, blockPos, blockState2);
			if (this.canSpreadTo(level, pos, blockState, Direction.DOWN, blockPos, blockState2, level.getFluidState(blockPos), fluidState.getType())) {
				this.spreadTo(level, blockPos, blockState2, Direction.DOWN, fluidState);
				if (this.sourceNeighborCount(level, pos) >= 3) {
					this.spreadToSides(level, pos, state, blockState);
				}
			} else if (state.isSource() || !this.isWaterHole(level, fluidState.getType(), pos, blockState, blockPos, blockState2)) {
				this.spreadToSides(level, pos, state, blockState);
			}
		}
	}

	private void spreadToSides(Level level, BlockPos pos, FluidState fluidState, BlockState blockState) {
		int i = fluidState.getAmount() - this.getDropOff(level);
		if ((Boolean)fluidState.getValue(FALLING)) {
			i = 7;
		}

		if (i > 0) {
			Map<Direction, FluidState> map = this.getSpread(level, pos, blockState);

			for (Entry<Direction, FluidState> entry : map.entrySet()) {
				Direction direction = (Direction)entry.getKey();
				FluidState fluidState2 = (FluidState)entry.getValue();
				BlockPos blockPos = pos.relative(direction);
				BlockState blockState2 = level.getBlockState(blockPos);
				if (this.canSpreadTo(level, pos, blockState, direction, blockPos, blockState2, level.getFluidState(blockPos), fluidState2.getType())) {
					this.spreadTo(level, blockPos, blockState2, direction, fluidState2);
				}
			}
		}
	}

	protected FluidState getNewLiquid(Level level, BlockPos pos, BlockState blockState) {
		int i = 0;
		int j = 0;

		for (Direction direction : Direction.Plane.HORIZONTAL) {
			BlockPos blockPos = pos.relative(direction);
			BlockState blockState2 = level.getBlockState(blockPos);
			FluidState fluidState = blockState2.getFluidState();
			if (fluidState.getType().isSame(this) && this.canPassThroughWall(direction, level, pos, blockState, blockPos, blockState2)) {
				if (fluidState.isSource()) {
					j++;
				}

				i = Math.max(i, fluidState.getAmount());
			}
		}

		if (this.canConvertToSource(level) && j >= 2) {
			BlockState blockState3 = level.getBlockState(pos.below());
			FluidState fluidState2 = blockState3.getFluidState();
			if (blockState3.isSolid() || this.isSourceBlockOfThisType(fluidState2)) {
				return this.getSource(false);
			}
		}

		BlockPos blockPos2 = pos.above();
		BlockState blockState4 = level.getBlockState(blockPos2);
		FluidState fluidState3 = blockState4.getFluidState();
		if (!fluidState3.isEmpty() && fluidState3.getType().isSame(this) && this.canPassThroughWall(Direction.UP, level, pos, blockState, blockPos2, blockState4)) {
			return this.getFlowing(8, true);
		} else {
			int k = i - this.getDropOff(level);
			return k <= 0 ? Fluids.EMPTY.defaultFluidState() : this.getFlowing(k, false);
		}
	}

	private boolean canPassThroughWall(Direction direction, BlockGetter level, BlockPos pos, BlockState state, BlockPos spreadPos, BlockState spreadState) {
		Object2ByteLinkedOpenHashMap<Block.BlockStatePairKey> object2ByteLinkedOpenHashMap;
		if (!state.getBlock().hasDynamicShape() && !spreadState.getBlock().hasDynamicShape()) {
			object2ByteLinkedOpenHashMap = (Object2ByteLinkedOpenHashMap<Block.BlockStatePairKey>)OCCLUSION_CACHE.get();
		} else {
			object2ByteLinkedOpenHashMap = null;
		}

		Block.BlockStatePairKey blockStatePairKey;
		if (object2ByteLinkedOpenHashMap != null) {
			blockStatePairKey = new Block.BlockStatePairKey(state, spreadState, direction);
			byte b = object2ByteLinkedOpenHashMap.getAndMoveToFirst(blockStatePairKey);
			if (b != 127) {
				return b != 0;
			}
		} else {
			blockStatePairKey = null;
		}

		VoxelShape voxelShape = state.getCollisionShape(level, pos);
		VoxelShape voxelShape2 = spreadState.getCollisionShape(level, spreadPos);
		boolean bl = !Shapes.mergedFaceOccludes(voxelShape, voxelShape2, direction);
		if (object2ByteLinkedOpenHashMap != null) {
			if (object2ByteLinkedOpenHashMap.size() == 200) {
				object2ByteLinkedOpenHashMap.removeLastByte();
			}

			object2ByteLinkedOpenHashMap.putAndMoveToFirst(blockStatePairKey, (byte)(bl ? 1 : 0));
		}

		return bl;
	}

	public abstract Fluid getFlowing();

	public FluidState getFlowing(int level, boolean falling) {
		return this.getFlowing().defaultFluidState().setValue(LEVEL, level).setValue(FALLING, falling);
	}

	public abstract Fluid getSource();

	public FluidState getSource(boolean falling) {
		return this.getSource().defaultFluidState().setValue(FALLING, falling);
	}

	protected abstract boolean canConvertToSource(Level level);

	protected void spreadTo(LevelAccessor level, BlockPos pos, BlockState blockState, Direction direction, FluidState fluidState) {
		if (blockState.getBlock() instanceof LiquidBlockContainer) {
			((LiquidBlockContainer)blockState.getBlock()).placeLiquid(level, pos, blockState, fluidState);
		} else {
			if (!blockState.isAir()) {
				this.beforeDestroyingBlock(level, pos, blockState);
			}

			level.setBlock(pos, fluidState.createLegacyBlock(), 3);
		}
	}

	protected abstract void beforeDestroyingBlock(LevelAccessor level, BlockPos pos, BlockState state);

	private static short getCacheKey(BlockPos sourcePos, BlockPos spreadPos) {
		int i = spreadPos.getX() - sourcePos.getX();
		int j = spreadPos.getZ() - sourcePos.getZ();
		return (short)((i + 128 & 0xFF) << 8 | j + 128 & 0xFF);
	}

	protected int getSlopeDistance(
		LevelReader level,
		BlockPos spreadPos,
		int distance,
		Direction direction,
		BlockState currentSpreadState,
		BlockPos sourcePos,
		Short2ObjectMap<Pair<BlockState, FluidState>> stateCache,
		Short2BooleanMap waterHoleCache
	) {
		int i = 1000;

		for (Direction direction2 : Direction.Plane.HORIZONTAL) {
			if (direction2 != direction) {
				BlockPos blockPos = spreadPos.relative(direction2);
				short s = getCacheKey(sourcePos, blockPos);
				Pair<BlockState, FluidState> pair = stateCache.computeIfAbsent(s, (Short2ObjectFunction<? extends Pair<BlockState, FluidState>>)(sx -> {
					BlockState blockStatex = level.getBlockState(blockPos);
					return Pair.of(blockStatex, blockStatex.getFluidState());
				}));
				BlockState blockState = pair.getFirst();
				FluidState fluidState = pair.getSecond();
				if (this.canPassThrough(level, this.getFlowing(), spreadPos, currentSpreadState, direction2, blockPos, blockState, fluidState)) {
					boolean bl = waterHoleCache.computeIfAbsent(s, (Short2BooleanFunction)(sx -> {
						BlockPos blockPos2 = blockPos.below();
						BlockState blockState2 = level.getBlockState(blockPos2);
						return this.isWaterHole(level, this.getFlowing(), blockPos, blockState, blockPos2, blockState2);
					}));
					if (bl) {
						return distance;
					}

					if (distance < this.getSlopeFindDistance(level)) {
						int j = this.getSlopeDistance(level, blockPos, distance + 1, direction2.getOpposite(), blockState, sourcePos, stateCache, waterHoleCache);
						if (j < i) {
							i = j;
						}
					}
				}
			}
		}

		return i;
	}

	private boolean isWaterHole(BlockGetter level, Fluid fluid, BlockPos pos, BlockState state, BlockPos spreadPos, BlockState spreadState) {
		if (!this.canPassThroughWall(Direction.DOWN, level, pos, state, spreadPos, spreadState)) {
			return false;
		} else {
			return spreadState.getFluidState().getType().isSame(this) ? true : this.canHoldFluid(level, spreadPos, spreadState, fluid);
		}
	}

	private boolean canPassThrough(
		BlockGetter level, Fluid fluid, BlockPos pos, BlockState state, Direction direction, BlockPos spreadPos, BlockState spreadState, FluidState fluidState
	) {
		return !this.isSourceBlockOfThisType(fluidState)
			&& this.canPassThroughWall(direction, level, pos, state, spreadPos, spreadState)
			&& this.canHoldFluid(level, spreadPos, spreadState, fluid);
	}

	private boolean isSourceBlockOfThisType(FluidState state) {
		return state.getType().isSame(this) && state.isSource();
	}

	protected abstract int getSlopeFindDistance(LevelReader level);

	/**
	 * Returns the number of immediately adjacent source blocks of the same fluid that lie on the horizontal plane.
	 */
	private int sourceNeighborCount(LevelReader level, BlockPos pos) {
		int i = 0;

		for (Direction direction : Direction.Plane.HORIZONTAL) {
			BlockPos blockPos = pos.relative(direction);
			FluidState fluidState = level.getFluidState(blockPos);
			if (this.isSourceBlockOfThisType(fluidState)) {
				i++;
			}
		}

		return i;
	}

	protected Map<Direction, FluidState> getSpread(Level level, BlockPos pos, BlockState state) {
		int i = 1000;
		Map<Direction, FluidState> map = Maps.newEnumMap(Direction.class);
		Short2ObjectMap<Pair<BlockState, FluidState>> short2ObjectMap = new Short2ObjectOpenHashMap<>();
		Short2BooleanMap short2BooleanMap = new Short2BooleanOpenHashMap();

		for (Direction direction : Direction.Plane.HORIZONTAL) {
			BlockPos blockPos = pos.relative(direction);
			short s = getCacheKey(pos, blockPos);
			Pair<BlockState, FluidState> pair = short2ObjectMap.computeIfAbsent(s, (Short2ObjectFunction<? extends Pair<BlockState, FluidState>>)(sx -> {
				BlockState blockStatex = level.getBlockState(blockPos);
				return Pair.of(blockStatex, blockStatex.getFluidState());
			}));
			BlockState blockState = pair.getFirst();
			FluidState fluidState = pair.getSecond();
			FluidState fluidState2 = this.getNewLiquid(level, blockPos, blockState);
			if (this.canPassThrough(level, fluidState2.getType(), pos, state, direction, blockPos, blockState, fluidState)) {
				BlockPos blockPos2 = blockPos.below();
				boolean bl = short2BooleanMap.computeIfAbsent(s, (Short2BooleanFunction)(sx -> {
					BlockState blockState2 = level.getBlockState(blockPos2);
					return this.isWaterHole(level, this.getFlowing(), blockPos, blockState, blockPos2, blockState2);
				}));
				int j;
				if (bl) {
					j = 0;
				} else {
					j = this.getSlopeDistance(level, blockPos, 1, direction.getOpposite(), blockState, pos, short2ObjectMap, short2BooleanMap);
				}

				if (j < i) {
					map.clear();
				}

				if (j <= i) {
					map.put(direction, fluidState2);
					i = j;
				}
			}
		}

		return map;
	}

	private boolean canHoldFluid(BlockGetter level, BlockPos pos, BlockState state, Fluid fluid) {
		Block block = state.getBlock();
		if (block instanceof LiquidBlockContainer liquidBlockContainer) {
			return liquidBlockContainer.canPlaceLiquid(null, level, pos, state, fluid);
		} else if (block instanceof DoorBlock
			|| state.is(BlockTags.SIGNS)
			|| state.is(Blocks.LADDER)
			|| state.is(Blocks.SUGAR_CANE)
			|| state.is(Blocks.BUBBLE_COLUMN)) {
			return false;
		} else {
			return !state.is(Blocks.NETHER_PORTAL) && !state.is(Blocks.END_PORTAL) && !state.is(Blocks.END_GATEWAY) && !state.is(Blocks.STRUCTURE_VOID)
				? !state.blocksMotion()
				: false;
		}
	}

	protected boolean canSpreadTo(
		BlockGetter level,
		BlockPos fromPos,
		BlockState fromBlockState,
		Direction direction,
		BlockPos toPos,
		BlockState toBlockState,
		FluidState toFluidState,
		Fluid fluid
	) {
		return toFluidState.canBeReplacedWith(level, toPos, fluid, direction)
			&& this.canPassThroughWall(direction, level, fromPos, fromBlockState, toPos, toBlockState)
			&& this.canHoldFluid(level, toPos, toBlockState, fluid);
	}

	protected abstract int getDropOff(LevelReader level);

	protected int getSpreadDelay(Level level, BlockPos pos, FluidState currentState, FluidState newState) {
		return this.getTickDelay(level);
	}

	@Override
	public void tick(Level level, BlockPos pos, FluidState state) {
		if (!state.isSource()) {
			FluidState fluidState = this.getNewLiquid(level, pos, level.getBlockState(pos));
			int i = this.getSpreadDelay(level, pos, state, fluidState);
			if (fluidState.isEmpty()) {
				state = fluidState;
				level.setBlock(pos, Blocks.AIR.defaultBlockState(), 3);
			} else if (!fluidState.equals(state)) {
				state = fluidState;
				BlockState blockState = fluidState.createLegacyBlock();
				level.setBlock(pos, blockState, 2);
				level.scheduleTick(pos, fluidState.getType(), i);
				level.updateNeighborsAt(pos, blockState.getBlock());
			}
		}

		this.spread(level, pos, state);
	}

	protected static int getLegacyLevel(FluidState state) {
		return state.isSource() ? 0 : 8 - Math.min(state.getAmount(), 8) + (state.getValue(FALLING) ? 8 : 0);
	}

	private static boolean hasSameAbove(FluidState fluidState, BlockGetter level, BlockPos pos) {
		return fluidState.getType().isSame(level.getFluidState(pos.above()).getType());
	}

	@Override
	public float getHeight(FluidState state, BlockGetter level, BlockPos pos) {
		return hasSameAbove(state, level, pos) ? 1.0F : state.getOwnHeight();
	}

	@Override
	public float getOwnHeight(FluidState state) {
		return state.getAmount() / 9.0F;
	}

	@Override
	public abstract int getAmount(FluidState state);

	@Override
	public VoxelShape getShape(FluidState state, BlockGetter level, BlockPos pos) {
		return state.getAmount() == 9 && hasSameAbove(state, level, pos)
			? Shapes.block()
			: (VoxelShape)this.shapes.computeIfAbsent(state, fluidState -> Shapes.box(0.0, 0.0, 0.0, 1.0, fluidState.getHeight(level, pos), 1.0));
	}
}