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

package net.minecraft.world.level.block;

import com.google.common.collect.Maps;
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.BlockStateProperties;
import net.minecraft.world.level.block.state.properties.IntegerProperty;
import net.minecraft.world.level.block.state.properties.RotationSegment;
import net.minecraft.world.phys.shapes.CollisionContext;
import net.minecraft.world.phys.shapes.VoxelShape;

public class BannerBlock extends AbstractBannerBlock {
    public static final MapCodec<BannerBlock> CODEC = RecordCodecBuilder.mapCodec(
        p_359965_ -> p_359965_.group(DyeColor.CODEC.fieldOf("color").forGetter(AbstractBannerBlock::getColor), propertiesCodec())
            .apply(p_359965_, BannerBlock::new)
    );
    public static final IntegerProperty ROTATION = BlockStateProperties.ROTATION_16;
    private static final Map<DyeColor, Block> BY_COLOR = Maps.newHashMap();
    private static final VoxelShape SHAPE = Block.column(8.0, 0.0, 16.0);

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

    public BannerBlock(DyeColor p_49012_, BlockBehaviour.Properties p_49013_) {
        super(p_49012_, p_49013_);
        this.registerDefaultState(this.stateDefinition.any().setValue(ROTATION, 0));
        BY_COLOR.put(p_49012_, this);
    }

    @Override
    protected boolean canSurvive(BlockState p_49019_, LevelReader p_49020_, BlockPos p_49021_) {
        return p_49020_.getBlockState(p_49021_.below()).isSolid();
    }

    @Override
    protected VoxelShape getShape(BlockState p_49038_, BlockGetter p_49039_, BlockPos p_49040_, CollisionContext p_49041_) {
        return SHAPE;
    }

    @Override
    public BlockState getStateForPlacement(BlockPlaceContext p_49017_) {
        return this.defaultBlockState().setValue(ROTATION, RotationSegment.convertToSegment(p_49017_.getRotation() + 180.0F));
    }

    @Override
    protected BlockState updateShape(
        BlockState p_49029_,
        LevelReader p_361162_,
        ScheduledTickAccess p_368795_,
        BlockPos p_49033_,
        Direction p_49030_,
        BlockPos p_49034_,
        BlockState p_49031_,
        RandomSource p_365337_
    ) {
        return p_49030_ == Direction.DOWN && !p_49029_.canSurvive(p_361162_, p_49033_)
            ? Blocks.AIR.defaultBlockState()
            : super.updateShape(p_49029_, p_361162_, p_368795_, p_49033_, p_49030_, p_49034_, p_49031_, p_365337_);
    }

    @Override
    protected BlockState rotate(BlockState p_49026_, Rotation p_49027_) {
        return p_49026_.setValue(ROTATION, p_49027_.rotate(p_49026_.getValue(ROTATION), 16));
    }

    @Override
    protected BlockState mirror(BlockState p_49023_, Mirror p_49024_) {
        return p_49023_.setValue(ROTATION, p_49024_.mirror(p_49023_.getValue(ROTATION), 16));
    }

    @Override
    protected void createBlockStateDefinition(StateDefinition.Builder<Block, BlockState> p_49036_) {
        p_49036_.add(ROTATION);
    }

    public static Block byColor(DyeColor p_49015_) {
        return BY_COLOR.getOrDefault(p_49015_, Blocks.WHITE_BANNER);
    }
}