src/common/buildcraft/api/liquids/LiquidStack.java

package buildcraft.api.liquids;

import net.minecraft.src.Block;
import net.minecraft.src.Item;
import net.minecraft.src.ItemStack;
import net.minecraft.src.NBTTagCompound;

/**
 * ItemStack substitute for liquids
 * @author SirSengir
 */
public class LiquidStack {
	public int itemID;
	public int amount;
	public int itemMeta;

	private LiquidStack() {
	}

	public LiquidStack(int itemID, int amount) {
		this(itemID, amount, 0);
	}

	public LiquidStack(Item item, int amount) {
		this(item.shiftedIndex, amount, 0);
	}

	public LiquidStack(Block block, int amount) {
		this(block.blockID, amount, 0);
	}

	public LiquidStack(int itemID, int amount, int itemDamage) {
		this.itemID = itemID;
		this.amount = amount;
		this.itemMeta = itemDamage;
	}

	public NBTTagCompound writeToNBT(NBTTagCompound nbttagcompound) {
		nbttagcompound.setShort("Id", (short) itemID);
		nbttagcompound.setInteger("Amount", amount);
		nbttagcompound.setShort("Meta", (short) itemMeta);
		return nbttagcompound;
	}

	public void readFromNBT(NBTTagCompound nbttagcompound) {
		itemID = nbttagcompound.getShort("Id");
		amount = nbttagcompound.getInteger("Amount");
		itemMeta = nbttagcompound.getShort("Meta");
	}

	/**
	 * @return A copy of this LiquidStack
	 */
	public LiquidStack copy() {
		return new LiquidStack(itemID, amount, itemMeta);
	}

	/**
	 * @param other 
	 * @return true if this LiquidStack contains the same liquid as the one passed in.
	 */
	public boolean isLiquidEqual(LiquidStack other) {
		if(other == null)
			return false;
		
		return itemID == other.itemID && itemMeta == other.itemMeta;
	}

	/**
	 * @param other
	 * @return true if this LiquidStack contains the other liquid (liquids are equal and amount >= other.amount).
	 */
	public boolean containsLiquid(LiquidStack other) {
		if(!isLiquidEqual(other))
			return false;
		
		return amount >= other.amount;
	}
	
	/**
	 * @param other ItemStack containing liquids. 
	 * @return true if this LiquidStack contains the same liquid as the one passed in.
	 */
	public boolean isLiquidEqual(ItemStack other) {
		if(other == null)
			return false;
		
		return itemID == other.itemID && itemMeta == other.getItemDamage();
	}
	
	/**
	 * @return ItemStack representation of this LiquidStack
	 */
	public ItemStack asItemStack() {
		return new ItemStack(itemID, 1, itemMeta);
	}

	/**
	 * Reads a liquid stack from the passed nbttagcompound and returns it.
	 * 
	 * @param nbttagcompound
	 * @return
	 */
	public static LiquidStack loadLiquidStackFromNBT(NBTTagCompound nbttagcompound) {
		LiquidStack liquidstack = new LiquidStack();
		liquidstack.readFromNBT(nbttagcompound);
		return liquidstack.itemID == 0 ? null : liquidstack;
	}
}