/**
 * Copyright (c) 2011-2015, SpaceToad and the BuildCraft Team
 * http://www.mod-buildcraft.com
 * <p/>
 * The BuildCraft API is distributed under the terms of the MIT License.
 * Please check the contents of the license, which should be located
 * as "LICENSE.API" in the BuildCraft source code distribution.
 */
package buildcraft.robotics;

import net.minecraft.item.ItemStack;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.world.World;

import net.minecraftforge.common.util.ForgeDirection;

import buildcraft.api.core.BlockIndex;
import buildcraft.api.robots.DockingStation;
import buildcraft.api.robots.IRequestProvider;
import buildcraft.api.robots.IRobotRegistry;
import buildcraft.api.robots.ResourceId;
import buildcraft.api.robots.ResourceIdRequest;
import buildcraft.api.robots.RobotManager;

public class StackRequest {
	private IRequestProvider requester;

	private int slot;

	private ItemStack stack;

	private DockingStation station;
	private BlockIndex stationIndex;
	private ForgeDirection stationSide;

	public StackRequest(IRequestProvider requester, int slot, ItemStack stack) {
		this.requester = requester;
		this.slot = slot;
		this.stack = stack;
		this.station = null;
	}

	private StackRequest(int slot, ItemStack stack, BlockIndex stationIndex, ForgeDirection stationSide) {
		requester = null;
		this.slot = slot;
		this.stack = stack;
		station = null;
		this.stationIndex = stationIndex;
		this.stationSide = stationSide;
	}

	public IRequestProvider getRequester(World world) {
		if (requester == null) {
			DockingStation dockingStation = getStation(world);
			if (dockingStation != null) {
				requester = dockingStation.getRequestProvider();
			}
		}
		return requester;
	}

	public int getSlot() {
		return slot;
	}

	public ItemStack getStack() {
		return stack;
	}

	public DockingStation getStation(World world) {
		if (station == null) {
			IRobotRegistry robotRegistry = RobotManager.registryProvider.getRegistry(world);
			station = robotRegistry.getStation(stationIndex.x, stationIndex.y, stationIndex.z, stationSide);
		}
		return station;
	}

	public void setStation(DockingStation station) {
		this.station = station;
		this.stationIndex = station.index();
		this.stationSide = station.side();
	}

	public void writeToNBT(NBTTagCompound nbt) {
		nbt.setInteger("slot", slot);

		NBTTagCompound stackNBT = new NBTTagCompound();
		stack.writeToNBT(stackNBT);
		nbt.setTag("stack", stackNBT);

		if (station != null) {
			NBTTagCompound stationIndexNBT = new NBTTagCompound();
			station.index().writeTo(stationIndexNBT);
			nbt.setTag("stationIndex", stationIndexNBT);
			nbt.setByte("stationSide", (byte) station.side().ordinal());
		}
	}

	public static StackRequest loadFromNBT(NBTTagCompound nbt) {
		if (nbt.hasKey("stationIndex")) {
			int slot = nbt.getInteger("slot");

			ItemStack stack = ItemStack.loadItemStackFromNBT(nbt.getCompoundTag("stack"));

			BlockIndex stationIndex = new BlockIndex(nbt.getCompoundTag("stationIndex"));
			ForgeDirection stationSide = ForgeDirection.values()[nbt.getByte("stationSide")];

			return new StackRequest(slot, stack, stationIndex, stationSide);
		} else {
			return null;
		}
	}

	public ResourceId getResourceId(World world) {
		return getStation(world) != null ? new ResourceIdRequest(getStation(world), slot) : null;
	}
}