/**
 * Copyright (c) 2011-2015, SpaceToad and the BuildCraft Team
 * http://www.mod-buildcraft.com
 * <p/>
 * BuildCraft is distributed under the terms of the Minecraft Mod Public
 * License 1.0, or MMPL. Please check the contents of the license located in
 * http://www.mod-buildcraft.com/MMPL-1.0.txt
 */
package buildcraft.core.lib;

import net.minecraft.block.Block;
import net.minecraft.tileentity.TileEntity;
import net.minecraft.world.World;

import net.minecraftforge.common.util.ForgeDirection;

import buildcraft.api.core.SafeTimeTracker;
import buildcraft.core.lib.utils.BlockUtils;
import buildcraft.core.lib.utils.Utils;

public final class TileBuffer {

	private Block block = null;
	private TileEntity tile;

	private final SafeTimeTracker tracker = new SafeTimeTracker(20, 5);
	private final World world;
	private final int x, y, z;
	private final boolean loadUnloaded;

	public TileBuffer(World world, int x, int y, int z, boolean loadUnloaded) {
		this.world = world;
		this.x = x;
		this.y = y;
		this.z = z;
		this.loadUnloaded = loadUnloaded;

		refresh();
	}

	public void refresh() {
		tile = null;
		block = null;

		if (!loadUnloaded && !world.blockExists(x, y, z)) {
			return;
		}

		block = world.getBlock(x, y, z);

		if (block != null && block.hasTileEntity(BlockUtils.getBlockMetadata(world, x, y, z))) {
			tile = world.getTileEntity(x, y, z);
		}
	}

	public void set(Block block, TileEntity tile) {
		this.block = block;
		this.tile = tile;
		tracker.markTime(world);
	}

	private void tryRefresh() {
		if (Utils.CAULDRON_DETECTED || (tile != null && tile.isInvalid()) || (tile == null && tracker.markTimeIfDelay(world))) {
			refresh();
		}
	}

	public Block getBlock() {
		tryRefresh();

		return block;
	}

	public TileEntity getTile() {
		return getTile(false);
	}

	public TileEntity getTile(boolean forceUpdate) {
		if (!Utils.CAULDRON_DETECTED && tile != null && !tile.isInvalid()) {
			return tile;
		}

		if (Utils.CAULDRON_DETECTED || (forceUpdate && tile != null && tile.isInvalid()) || tracker.markTimeIfDelay(world)) {
			refresh();

			if (tile != null && !tile.isInvalid()) {
				return tile;
			}
		}

		return null;
	}

	public boolean exists() {
		if (tile != null && !Utils.CAULDRON_DETECTED && !tile.isInvalid()) {
			return true;
		}

		return world.blockExists(x, y, z);
	}

	public static TileBuffer[] makeBuffer(World world, int x, int y, int z, boolean loadUnloaded) {
		TileBuffer[] buffer = new TileBuffer[6];

		for (int i = 0; i < 6; i++) {
			ForgeDirection d = ForgeDirection.getOrientation(i);
			buffer[i] = new TileBuffer(world, x + d.offsetX, y + d.offsetY, z + d.offsetZ, loadUnloaded);
		}

		return buffer;
	}
}