TileEntityGristGatherer

package com.natura.minestuckarsenal.tileentity;

import java.util.ArrayList;
import java.util.List;

import javax.annotation.Nonnull;

import com.mraof.minestuck.entity.item.EntityGrist;

import net.minecraft.block.state.IBlockState;
import net.minecraft.entity.Entity;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.tileentity.TileEntity;
import net.minecraft.util.ClassInheritanceMultiMap;
import net.minecraft.util.ITickable;
import net.minecraft.util.math.AxisAlignedBB;
import net.minecraft.util.math.BlockPos;
import net.minecraft.util.math.MathHelper;
import net.minecraft.world.World;
import net.minecraft.world.chunk.Chunk;

/* Thanks to Ender IO team for the entity selection code. */

public class TileEntityGristGatherer extends TileEntity implements ITickable {

    int counter = 0;
    private int range = 8;
    EntityPlayer player;

    public TileEntityGristGatherer(EntityPlayer player) {
        this.player = player;
    }

    public @Nonnull AxisAlignedBB getBounds() {
        return new AxisAlignedBB(getPos()).expand(getRange() + (range == 0 ? 1 / 32f : 0), 0, getRange() + (range == 0 ? 1 / 32f : 0));
     }

     public float getRange() {
        return range;
     }

     @Override
     public NBTTagCompound writeToNBT(NBTTagCompound compound) {
        super.writeToNBT(compound);
        compound.setString("player", player.getName());
        return compound;
     }

     @Override
     public void readFromNBT(NBTTagCompound compound) {
        super.readFromNBT(compound);
        this.player = this.world.getPlayerEntityByName(compound.getString("player"));
     }

     @Override
     public boolean shouldRefresh(World world, BlockPos pos, IBlockState oldState, IBlockState newSate)
     {

         return oldState.getBlock() != newSate.getBlock();

     }

    @Override
    public void update() {
        NBTTagCompound compound = new NBTTagCompound();
        this.writeToNBT(compound);
        this.markDirty();

        if(counter == 20) {

            List<EntityGrist> list = selectEntitiesWithinAABB(this.getWorld(), getBounds());

            if(list.size() != 0) {
                    for(int i = 0; i == list.size() - 1; i++)
                    {
                        if(player != null && list.get(i) != null) {
                            list.get(i).addGrist(player);
                            list.get(i).setDead();
                        }
                    }
            }

            counter = 0;
        }

        else {
            counter++;
        }
    }

    private List<EntityGrist> selectEntitiesWithinAABB(World worldIn, AxisAlignedBB bb) {
        List<EntityGrist> result = new ArrayList<EntityGrist>();

        final int minChunkX = MathHelper.floor((bb.minX) / 16.0D);
        final int maxChunkX = MathHelper.floor((bb.maxX) / 16.0D);
        final int minChunkZ = MathHelper.floor((bb.minZ) / 16.0D);
        final int maxChunkZ = MathHelper.floor((bb.maxZ) / 16.0D);
        final int minChunkY = MathHelper.floor((bb.minY) / 16.0D);
        final int maxChunkY = MathHelper.floor((bb.maxY) / 16.0D);

        for (int chunkX = minChunkX; chunkX <= maxChunkX; ++chunkX) {
          for (int chunkZ = minChunkZ; chunkZ <= maxChunkZ; ++chunkZ) {
            Chunk chunk = worldIn.getChunkFromChunkCoords(chunkX, chunkZ);
            final ClassInheritanceMultiMap<Entity>[] entityLists = chunk.getEntityLists();
            final int minChunkYClamped = MathHelper.clamp(minChunkY, 0, entityLists.length - 1);
            final int maxChunkYClamped = MathHelper.clamp(maxChunkY, 0, entityLists.length - 1);
            for (int chunkY = minChunkYClamped; chunkY <= maxChunkYClamped; ++chunkY) {
              for (Entity entity : entityLists[chunkY]) {
                if (!entity.isDead && (entity instanceof EntityGrist) && entity.getEntityBoundingBox().intersects(bb)) {
                  result.add((EntityGrist) entity);

                    return result;

                }
              }
            }
          }
        }

        return result;
      }

}