ContainerEnchanter.java

package crazypants.enderio.machine.enchanter;

import java.util.List;

import net.minecraft.enchantment.EnchantmentData;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.entity.player.InventoryPlayer;
import net.minecraft.init.Items;
import net.minecraft.inventory.Slot;
import net.minecraft.item.ItemStack;

import com.enderio.core.client.gui.widget.GhostBackgroundItemSlot;
import com.enderio.core.client.gui.widget.GhostSlot;
import com.enderio.core.common.ContainerEnder;

import crazypants.enderio.EnderIO;

public class ContainerEnchanter extends ContainerEnder<TileEnchanter> {

  public ContainerEnchanter(EntityPlayer player, InventoryPlayer playerInv, TileEnchanter te) {
    super(playerInv, te);
  }
  
  @Override
  protected void addSlots(InventoryPlayer playerInv) {

    final TileEnchanter te = getInv();
    
    addSlotToContainer(new Slot(te, 0, 27, 35) {

      @Override
      public int getSlotStackLimit() {
        return 1;
      }

      @Override
      public boolean isItemValid(ItemStack itemStack) {
        return te.isItemValidForSlot(0, itemStack);
      }

      @Override
      public void onSlotChanged() {
        updateOutput();
      }

    });

    addSlotToContainer(new Slot(te, 1, 76, 35) {

      @Override
      public boolean isItemValid(ItemStack itemStack) {
        return te.isItemValidForSlot(1, itemStack);
      }

      @Override
      public void onSlotChanged() {
        updateOutput();
      }

    });

    addSlotToContainer(new Slot(te, 2, 134, 35) {

      @Override
      public int getSlotStackLimit() {
        return 1;
      }

      @Override
      public boolean isItemValid(ItemStack itemStack) {
        return false;
      }

      @Override
      public void onPickupFromSlot(EntityPlayer player, ItemStack stack) {
        if(!player.capabilities.isCreativeMode) {
          player.addExperienceLevel(-te.getCurrentEnchantmentCost());
        }
        EnchantmentData enchData = te.getCurrentEnchantmentData();
        EnchanterRecipe recipe = te.getCurrentEnchantmentRecipe();
        ItemStack curStack = te.getStackInSlot(1);
        if(recipe == null || enchData == null || curStack == null || enchData.enchantmentLevel >= curStack.stackSize) {
          te.setInventorySlotContents(1, (ItemStack) null);
        } else {

          curStack = curStack.copy();
          curStack.stackSize -= recipe.getItemsPerLevel() * enchData.enchantmentLevel;
          if(curStack.stackSize > 0) {
            te.setInventorySlotContents(1, curStack);
          } else {
            te.setInventorySlotContents(1, null);
          }
          te.markDirty();
        }

        te.setInventorySlotContents(0, (ItemStack) null);
        if (!te.getWorldObj().isRemote) {
          te.getWorldObj().playAuxSFX(1021, te.xCoord, te.yCoord, te.zCoord, 0);
        }
      }

      @Override
      public boolean canTakeStack(EntityPlayer player) {
        return playerHasEnoughLevels(player);
      }

    });
  }

  public void createGhostSlots(List<GhostSlot> slots) {
    slots.add(new GhostBackgroundItemSlot(Items.writable_book, 27, 35));
  }

  public boolean playerHasEnoughLevels(EntityPlayer player) {
    if(player.capabilities.isCreativeMode) {
      return true;
    }
    return player.experienceLevel >= getInv().getCurrentEnchantmentCost();
  }

  private void updateOutput() {
    ItemStack output = null;
    EnchantmentData enchantment = getInv().getCurrentEnchantmentData();
    if(enchantment != null) {
      output = new ItemStack(Items.enchanted_book);
      Items.enchanted_book.addEnchantment(output, enchantment);
    }
    getInv().setOutput(output);
  }

  @Override
  public ItemStack transferStackInSlot(EntityPlayer par1EntityPlayer, int par2) {
    ItemStack copyStack = null;
    Slot slot = (Slot) inventorySlots.get(par2);

    if (slot != null && slot.getHasStack()) {
      ItemStack origStack = slot.getStack();
      copyStack = origStack.copy();

      if (par2 <= 2) {
        if (!mergeItemStack(origStack, 2, inventorySlots.size(), true)) {
          return null;
        }
      } else {
        if (!getInv().isItemValidForSlot(0, origStack) || !mergeItemStack(origStack, 0, 1, false)) {
          if (!getInv().isItemValidForSlot(1, origStack) || !mergeItemStack(origStack, 1, 2, false)) {
            return null;
          }
        }
      }
      if (origStack.stackSize == 0) {
        slot.putStack((ItemStack) null);
      } else {
        slot.onSlotChanged();
      }
      slot.onPickupFromSlot(par1EntityPlayer, origStack);
    }
    return copyStack;
  }
}