Block bed placement duplicating crops

BlockBedCropDupe.java

package com.github.jikoo.blockbedcropdupe;

import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.bukkit.Material;
import org.bukkit.block.Block;
import org.bukkit.block.BlockFace;
import org.bukkit.block.BlockState;
import org.bukkit.block.data.Ageable;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.EventPriority;
import org.bukkit.event.Listener;
import org.bukkit.event.block.Action;
import org.bukkit.event.block.BlockMultiPlaceEvent;
import org.bukkit.event.player.PlayerInteractEvent;
import org.bukkit.plugin.java.JavaPlugin;
import org.jetbrains.annotations.NotNull;

public class BlockBedCropDupe extends JavaPlugin implements Listener {

  private final BlockFace[] adjacents = {
      BlockFace.NORTH,
      BlockFace.SOUTH,
      BlockFace.EAST,
      BlockFace.WEST
  };
  private final Map<Material, MultiBlockShape> multiBlocks = new HashMap<>();

  @Override
  public void onEnable() {
    MultiBlockShape bedShape = (block, player) -> Arrays.asList(
        block.getState(),
        block.getRelative(player.getFacing()).getState()
    );
    for (Material material : Material.values()) {
      if (material.name().endsWith("_BED")) {
        multiBlocks.put(material, bedShape);
      }
    }

    getServer().getPluginManager().registerEvents(this, this);
  }

  @Override
  public void onDisable() {
    multiBlocks.clear();
  }

  public void addMultiBlockMat(@NotNull Material material, @NotNull MultiBlockShape shape) {
    multiBlocks.put(material, shape);
  }

  @EventHandler(ignoreCancelled = true, priority = EventPriority.HIGH)
  private void preBlockMultiPlace(@NotNull PlayerInteractEvent event) {
    if (event.getAction() != Action.RIGHT_CLICK_BLOCK
        || event.getClickedBlock() == null
        || event.getItem() == null) {
      // Non-placement.
      return;
    }

    MultiBlockShape shape = multiBlocks.get(event.getItem().getType());

    if (shape == null) {
      // Non-multiblock placement.
      return;
    }

    // Fast-placing client sends placement packets on ghost blocks. Since the ghost block is air,
    // the block is placed inside it instead.
    Block placeLocation;
    if (event.getClickedBlock().getType() == Material.AIR) {
      placeLocation = event.getClickedBlock();
    } else {
      placeLocation = event.getClickedBlock().getRelative(event.getBlockFace());
    }

    // Server only erroneously updates blocks adjacent to the origin block, i.e. the bed foot.
    boolean adjacentCrop = false;
    for (BlockFace adjacentFace : adjacents) {
      if (placeLocation.getRelative(adjacentFace).getBlockData() instanceof Ageable) {
        // There's an adjacent crop, this is a potential dupe.
        adjacentCrop = true;
        break;
      }
    }

    if (!adjacentCrop) {
      // No adjacent crops, no dupe risk.
      return;
    }

    BlockMultiPlaceEvent fakeEvent = new BlockMultiPlaceEvent(
        shape.getBlocks(placeLocation, event.getPlayer()),
        placeLocation,
        event.getItem(),
        event.getPlayer(),
        true);
    getServer().getPluginManager().callEvent(fakeEvent);

    if (fakeEvent.isCancelled()) {
      // Protection plugin cancelled our pre-fire event.
      event.setCancelled(true);
    }
  }

  public interface MultiBlockShape {
    @NotNull List<BlockState> getBlocks(@NotNull Block start, @NotNull Player player);
  }
}

plugin.yml

main: com.github.jikoo.blockbedcropdupe.BlockBedCropDupe
name: BlockBedCropDupe
version: ${project.version}
api-version: 1.13
author: Jikoo