Code/net/minecraft/world/level/block/WallBannerBlock.java

package net.minecraft.world.level.block;

import com.mojang.serialization.MapCodec;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import com.mojang.serialization.codecs.RecordCodecBuilder.Instance;
import java.util.Map;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.util.RandomSource;
import net.minecraft.world.item.DyeColor;
import net.minecraft.world.item.context.BlockPlaceContext;
import net.minecraft.world.level.BlockGetter;
import net.minecraft.world.level.LevelReader;
import net.minecraft.world.level.ScheduledTickAccess;
import net.minecraft.world.level.block.state.BlockBehaviour;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.block.state.StateDefinition;
import net.minecraft.world.level.block.state.properties.EnumProperty;
import net.minecraft.world.phys.shapes.CollisionContext;
import net.minecraft.world.phys.shapes.Shapes;
import net.minecraft.world.phys.shapes.VoxelShape;

public class WallBannerBlock extends AbstractBannerBlock {
    public static final MapCodec<WallBannerBlock> CODEC = RecordCodecBuilder.mapCodec(
        p_360460_ -> p_360460_.group(DyeColor.CODEC.fieldOf("color").forGetter(AbstractBannerBlock::getColor), propertiesCodec())
            .apply(p_360460_, WallBannerBlock::new)
    );
    public static final EnumProperty<Direction> FACING = HorizontalDirectionalBlock.FACING;
    private static final Map<Direction, VoxelShape> SHAPES = Shapes.rotateHorizontal(Block.boxZ(16.0, 0.0, 12.5, 14.0, 16.0));

    @Override
    public MapCodec<WallBannerBlock> codec() {
        return CODEC;
    }

    public WallBannerBlock(DyeColor p_57920_, BlockBehaviour.Properties p_57921_) {
        super(p_57920_, p_57921_);
        this.registerDefaultState(this.stateDefinition.any().setValue(FACING, Direction.NORTH));
    }

    @Override
    protected boolean canSurvive(BlockState p_57925_, LevelReader p_57926_, BlockPos p_57927_) {
        return p_57926_.getBlockState(p_57927_.relative(p_57925_.getValue(FACING).getOpposite())).isSolid();
    }

    @Override
    protected BlockState updateShape(
        BlockState p_57935_,
        LevelReader p_365367_,
        ScheduledTickAccess p_369434_,
        BlockPos p_57939_,
        Direction p_57936_,
        BlockPos p_57940_,
        BlockState p_57937_,
        RandomSource p_362270_
    ) {
        return p_57936_ == p_57935_.getValue(FACING).getOpposite() && !p_57935_.canSurvive(p_365367_, p_57939_)
            ? Blocks.AIR.defaultBlockState()
            : super.updateShape(p_57935_, p_365367_, p_369434_, p_57939_, p_57936_, p_57940_, p_57937_, p_362270_);
    }

    @Override
    protected VoxelShape getShape(BlockState p_57944_, BlockGetter p_57945_, BlockPos p_57946_, CollisionContext p_57947_) {
        return SHAPES.get(p_57944_.getValue(FACING));
    }

    @Override
    public BlockState getStateForPlacement(BlockPlaceContext p_57923_) {
        BlockState blockstate = this.defaultBlockState();
        LevelReader levelreader = p_57923_.getLevel();
        BlockPos blockpos = p_57923_.getClickedPos();
        Direction[] adirection = p_57923_.getNearestLookingDirections();

        for (Direction direction : adirection) {
            if (direction.getAxis().isHorizontal()) {
                Direction direction1 = direction.getOpposite();
                blockstate = blockstate.setValue(FACING, direction1);
                if (blockstate.canSurvive(levelreader, blockpos)) {
                    return blockstate;
                }
            }
        }

        return null;
    }

    @Override
    protected BlockState rotate(BlockState p_57932_, Rotation p_57933_) {
        return p_57932_.setValue(FACING, p_57933_.rotate(p_57932_.getValue(FACING)));
    }

    @Override
    protected BlockState mirror(BlockState p_57929_, Mirror p_57930_) {
        return p_57929_.rotate(p_57930_.getRotation(p_57929_.getValue(FACING)));
    }

    @Override
    protected void createBlockStateDefinition(StateDefinition.Builder<Block, BlockState> p_57942_) {
        p_57942_.add(FACING);
    }
}