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

package net.minecraft.world.level.block;

import com.mojang.serialization.MapCodec;
import java.util.List;
import javax.annotation.Nullable;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.server.level.ServerLevel;
import net.minecraft.sounds.SoundEvents;
import net.minecraft.sounds.SoundSource;
import net.minecraft.util.RandomSource;
import net.minecraft.world.InteractionResult;
import net.minecraft.world.entity.decoration.ItemFrame;
import net.minecraft.world.entity.player.Player;
import net.minecraft.world.level.BlockGetter;
import net.minecraft.world.level.Level;
import net.minecraft.world.level.LevelReader;
import net.minecraft.world.level.ScheduledTickAccess;
import net.minecraft.world.level.block.entity.BlockEntity;
import net.minecraft.world.level.block.entity.ComparatorBlockEntity;
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.ComparatorMode;
import net.minecraft.world.level.block.state.properties.EnumProperty;
import net.minecraft.world.phys.AABB;
import net.minecraft.world.phys.BlockHitResult;
import net.minecraft.world.ticks.TickPriority;

public class ComparatorBlock extends DiodeBlock implements EntityBlock {
    public static final MapCodec<ComparatorBlock> CODEC = simpleCodec(ComparatorBlock::new);
    public static final EnumProperty<ComparatorMode> MODE = BlockStateProperties.MODE_COMPARATOR;

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

    public ComparatorBlock(BlockBehaviour.Properties p_51857_) {
        super(p_51857_);
        this.registerDefaultState(this.stateDefinition.any().setValue(FACING, Direction.NORTH).setValue(POWERED, false).setValue(MODE, ComparatorMode.COMPARE));
    }

    @Override
    protected int getDelay(BlockState p_51912_) {
        return 2;
    }

    @Override
    public BlockState updateShape(
        BlockState p_298756_,
        LevelReader p_361531_,
        ScheduledTickAccess p_368115_,
        BlockPos p_299729_,
        Direction p_300136_,
        BlockPos p_297639_,
        BlockState p_299304_,
        RandomSource p_368851_
    ) {
        return p_300136_ == Direction.DOWN && !this.canSurviveOn(p_361531_, p_297639_, p_299304_)
            ? Blocks.AIR.defaultBlockState()
            : super.updateShape(p_298756_, p_361531_, p_368115_, p_299729_, p_300136_, p_297639_, p_299304_, p_368851_);
    }

    @Override
    protected int getOutputSignal(BlockGetter p_51892_, BlockPos p_51893_, BlockState p_51894_) {
        BlockEntity blockentity = p_51892_.getBlockEntity(p_51893_);
        return blockentity instanceof ComparatorBlockEntity ? ((ComparatorBlockEntity)blockentity).getOutputSignal() : 0;
    }

    private int calculateOutputSignal(Level p_51904_, BlockPos p_51905_, BlockState p_51906_) {
        int i = this.getInputSignal(p_51904_, p_51905_, p_51906_);
        if (i == 0) {
            return 0;
        } else {
            int j = this.getAlternateSignal(p_51904_, p_51905_, p_51906_);
            if (j > i) {
                return 0;
            } else {
                return p_51906_.getValue(MODE) == ComparatorMode.SUBTRACT ? i - j : i;
            }
        }
    }

    @Override
    protected boolean shouldTurnOn(Level p_51861_, BlockPos p_51862_, BlockState p_51863_) {
        int i = this.getInputSignal(p_51861_, p_51862_, p_51863_);
        if (i == 0) {
            return false;
        } else {
            int j = this.getAlternateSignal(p_51861_, p_51862_, p_51863_);
            return i > j ? true : i == j && p_51863_.getValue(MODE) == ComparatorMode.COMPARE;
        }
    }

    @Override
    protected int getInputSignal(Level p_51896_, BlockPos p_51897_, BlockState p_51898_) {
        int i = super.getInputSignal(p_51896_, p_51897_, p_51898_);
        Direction direction = p_51898_.getValue(FACING);
        BlockPos blockpos = p_51897_.relative(direction);
        BlockState blockstate = p_51896_.getBlockState(blockpos);
        if (blockstate.hasAnalogOutputSignal()) {
            i = blockstate.getAnalogOutputSignal(p_51896_, blockpos);
        } else if (i < 15 && blockstate.isRedstoneConductor(p_51896_, blockpos)) {
            blockpos = blockpos.relative(direction);
            blockstate = p_51896_.getBlockState(blockpos);
            ItemFrame itemframe = this.getItemFrame(p_51896_, direction, blockpos);
            int j = Math.max(
                itemframe == null ? Integer.MIN_VALUE : itemframe.getAnalogOutput(),
                blockstate.hasAnalogOutputSignal() ? blockstate.getAnalogOutputSignal(p_51896_, blockpos) : Integer.MIN_VALUE
            );
            if (j != Integer.MIN_VALUE) {
                i = j;
            }
        }

        return i;
    }

    @Nullable
    private ItemFrame getItemFrame(Level p_51865_, Direction p_51866_, BlockPos p_51867_) {
        List<ItemFrame> list = p_51865_.getEntitiesOfClass(
            ItemFrame.class,
            new AABB(
                p_51867_.getX(), p_51867_.getY(), p_51867_.getZ(), p_51867_.getX() + 1, p_51867_.getY() + 1, p_51867_.getZ() + 1
            ),
            p_360423_ -> p_360423_ != null && p_360423_.getDirection() == p_51866_
        );
        return list.size() == 1 ? list.get(0) : null;
    }

    @Override
    protected InteractionResult useWithoutItem(BlockState p_51880_, Level p_51881_, BlockPos p_51882_, Player p_51883_, BlockHitResult p_51885_) {
        if (!p_51883_.getAbilities().mayBuild) {
            return InteractionResult.PASS;
        } else {
            p_51880_ = p_51880_.cycle(MODE);
            float f = p_51880_.getValue(MODE) == ComparatorMode.SUBTRACT ? 0.55F : 0.5F;
            p_51881_.playSound(p_51883_, p_51882_, SoundEvents.COMPARATOR_CLICK, SoundSource.BLOCKS, 0.3F, f);
            p_51881_.setBlock(p_51882_, p_51880_, 2);
            this.refreshOutputState(p_51881_, p_51882_, p_51880_);
            return InteractionResult.SUCCESS;
        }
    }

    @Override
    protected void checkTickOnNeighbor(Level p_51900_, BlockPos p_51901_, BlockState p_51902_) {
        if (!p_51900_.getBlockTicks().willTickThisTick(p_51901_, this)) {
            int i = this.calculateOutputSignal(p_51900_, p_51901_, p_51902_);
            BlockEntity blockentity = p_51900_.getBlockEntity(p_51901_);
            int j = blockentity instanceof ComparatorBlockEntity ? ((ComparatorBlockEntity)blockentity).getOutputSignal() : 0;
            if (i != j || p_51902_.getValue(POWERED) != this.shouldTurnOn(p_51900_, p_51901_, p_51902_)) {
                TickPriority tickpriority = this.shouldPrioritize(p_51900_, p_51901_, p_51902_) ? TickPriority.HIGH : TickPriority.NORMAL;
                p_51900_.scheduleTick(p_51901_, this, 2, tickpriority);
            }
        }
    }

    private void refreshOutputState(Level p_51908_, BlockPos p_51909_, BlockState p_51910_) {
        int i = this.calculateOutputSignal(p_51908_, p_51909_, p_51910_);
        BlockEntity blockentity = p_51908_.getBlockEntity(p_51909_);
        int j = 0;
        if (blockentity instanceof ComparatorBlockEntity comparatorblockentity) {
            j = comparatorblockentity.getOutputSignal();
            comparatorblockentity.setOutputSignal(i);
        }

        if (j != i || p_51910_.getValue(MODE) == ComparatorMode.COMPARE) {
            boolean flag1 = this.shouldTurnOn(p_51908_, p_51909_, p_51910_);
            boolean flag = p_51910_.getValue(POWERED);
            if (flag && !flag1) {
                p_51908_.setBlock(p_51909_, p_51910_.setValue(POWERED, false), 2);
            } else if (!flag && flag1) {
                p_51908_.setBlock(p_51909_, p_51910_.setValue(POWERED, true), 2);
            }

            this.updateNeighborsInFront(p_51908_, p_51909_, p_51910_);
        }
    }

    @Override
    protected void tick(BlockState p_221010_, ServerLevel p_221011_, BlockPos p_221012_, RandomSource p_221013_) {
        this.refreshOutputState(p_221011_, p_221012_, p_221010_);
    }

    @Override
    protected boolean triggerEvent(BlockState p_51874_, Level p_51875_, BlockPos p_51876_, int p_51877_, int p_51878_) {
        super.triggerEvent(p_51874_, p_51875_, p_51876_, p_51877_, p_51878_);
        BlockEntity blockentity = p_51875_.getBlockEntity(p_51876_);
        return blockentity != null && blockentity.triggerEvent(p_51877_, p_51878_);
    }

    @Override
    public BlockEntity newBlockEntity(BlockPos p_153086_, BlockState p_153087_) {
        return new ComparatorBlockEntity(p_153086_, p_153087_);
    }

    @Override
    protected void createBlockStateDefinition(StateDefinition.Builder<Block, BlockState> p_51887_) {
        p_51887_.add(FACING, MODE, POWERED);
    }
}