TinkersConstruct/src/main/java/tconstruct/items/tools/PotionLauncher.java

package tconstruct.items.tools;

import java.util.List;

import net.minecraft.client.renderer.texture.IIconRegister;
import net.minecraft.creativetab.CreativeTabs;
import net.minecraft.entity.EntityLivingBase;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.entity.player.InventoryPlayer;
import net.minecraft.init.Items;
import net.minecraft.item.EnumAction;
import net.minecraft.item.Item;
import net.minecraft.item.ItemStack;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.util.IIcon;
import net.minecraft.util.StatCollector;
import net.minecraft.world.World;

import tconstruct.tools.entity.LaunchedPotion;

public class PotionLauncher extends Item {

    @SideOnly(Side.CLIENT)
    private IIcon[] icons;

    public static final String[] textureNames = new String[] { "potionlauncher" };

    public PotionLauncher() {
        super();
        this.maxStackSize = 1;
        this.setCreativeTab(CreativeTabs.tabCombat);
        this.setMaxDamage(3);
    }

    @Override
    public ItemStack onEaten(ItemStack stack, World world, EntityPlayer player) {
        NBTTagCompound tags = stack.getTagCompound().getCompoundTag("InfiTool");
        boolean loaded = tags.getBoolean("Loaded");
        if (!loaded) {
            int slotID = getInventorySlotContainItem(Items.potionitem, player.inventory);
            ItemStack potion = player.inventory.getStackInSlot(slotID);

            NBTTagCompound potionTag = new NBTTagCompound();
            potion.writeToNBT(potionTag);
            tags.setTag("LoadedPotion", potionTag);
            tags.setBoolean("Loaded", true);

            if (!player.capabilities.isCreativeMode) {
                potion.stackSize--;
                if (potion.stackSize < 1) player.inventory.setInventorySlotContents(slotID, null);
            }

            world.playSoundEffect(
                    player.posX,
                    player.posY,
                    player.posZ,
                    "tinker:launcher_clank",
                    1.0F,
                    (world.rand.nextFloat() - world.rand.nextFloat()) * 0.15F + 1.0F);
        }
        return stack;
    }

    @Override
    public void onPlayerStoppedUsing(ItemStack stack, World world, EntityPlayer player, int time) {}

    @Override
    public ItemStack onItemRightClick(ItemStack stack, World world, EntityPlayer player) {
        NBTTagCompound tags = stack.getTagCompound().getCompoundTag("InfiTool");
        int slotID = getInventorySlotContainItem(Items.potionitem, player.inventory);
        if (!tags.getBoolean("Loaded") && slotID >= 0) player.setItemInUse(stack, this.getMaxItemUseDuration(stack));
        return stack;
    }

    /**
     * How long it takes to use or consume an item
     */
    @Override
    public int getMaxItemUseDuration(ItemStack stack) {
        return 30;
    }

    /**
     * returns the action that specifies what animation to play when the items is being used
     */
    @Override
    public EnumAction getItemUseAction(ItemStack stack) {
        if (stack != null && stack.hasTagCompound()
                && !stack.getTagCompound().getCompoundTag("InfiTool").getBoolean("Loaded"))
            return EnumAction.bow;
        else return EnumAction.none;
    }

    @Override
    @SideOnly(Side.CLIENT)
    public void registerIcons(IIconRegister par1IconRegister) {
        this.icons = new IIcon[textureNames.length];

        for (int i = 0; i < this.icons.length; ++i) {
            this.icons[i] = par1IconRegister.registerIcon("tinker:" + textureNames[i]);
        }
    }

    @Override
    @SideOnly(Side.CLIENT)
    public IIcon getIconFromDamage(int meta) {
        return icons[0];
    }

    @Override
    public void getSubItems(Item b, CreativeTabs tabs, List list) {
        ItemStack stack = new ItemStack(b, 1, 0);
        NBTTagCompound compound = new NBTTagCompound();
        NBTTagCompound tags = new NBTTagCompound();
        compound.setTag("InfiTool", tags);

        tags.setBoolean("Loaded", false);

        stack.setTagCompound(compound);

        list.add(stack);
    }

    @Override
    public boolean onEntitySwing(EntityLivingBase player, ItemStack stack) {
        if (stack != null && stack.hasTagCompound()) {
            NBTTagCompound tags = stack.getTagCompound().getCompoundTag("InfiTool");
            if (tags.getBoolean("Loaded")) {
                NBTTagCompound potionTag = tags.getCompoundTag("LoadedPotion");
                ItemStack potion = ItemStack.loadItemStackFromNBT(potionTag); // findPotion(player);InventoryLogic
                if (potion != null) {
                    World world = player.worldObj;
                    world.playSoundAtEntity(player, "random.bow", 0.5F, 0.4F / (itemRand.nextFloat() * 0.4F + 0.8F));

                    if (!world.isRemote) {
                        world.spawnEntityInWorld(new LaunchedPotion(world, player, potion));
                    }
                    tags.removeTag("LoadedPotion");
                    tags.setBoolean("Loaded", false);
                }
                return true;
            }
        }
        return false;
    }

    ItemStack findPotion(EntityLivingBase living) {
        if (living instanceof EntityPlayer) {
            EntityPlayer player = (EntityPlayer) living;
            int potionSlot = getInventorySlotContainItem(Items.potionitem, player.inventory);
            if (potionSlot >= 0) {
                return player.inventory.getStackInSlot(potionSlot);
            }
        }
        return null;
    }

    int getInventorySlotContainItem(Item item, InventoryPlayer inventory) {
        for (int j = 0; j < inventory.mainInventory.length; ++j) {
            if (inventory.mainInventory[j] != null && inventory.mainInventory[j].getItem() == item) {
                return j;
            }
        }

        return -1;
    }

    @Override
    @SideOnly(Side.CLIENT)
    public void addInformation(ItemStack stack, EntityPlayer player, List list, boolean par4) {
        list.add(StatCollector.translateToLocal("potionlauncher.tooltip"));
    }
}