buildcraft/common/buildcraft/robotics/map/MapWorld.java

package buildcraft.robotics.map;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Comparator;
import java.util.Date;
import java.util.HashSet;
import java.util.Iterator;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Set;
import gnu.trove.map.hash.TLongObjectHashMap;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.world.World;
import buildcraft.core.lib.utils.NBTUtils;

public class MapWorld {
	private final World world;
	private final TLongObjectHashMap<MapRegion> regionMap;
	private final Set<QueuedXZ> regionUpdateSet = new HashSet<QueuedXZ>();
	private final Queue<QueuedXZ> queuedChunks;
	private final File location;

	private long lastForcedChunkLoad;

	private class QueuedXZ {
		int x, z, p;

		QueuedXZ(int x, int z, int p) {
			this.x = x;
			this.z = z;
			this.p = p;
		}

		@Override
		public boolean equals(Object other) {
			if (other == null || !(other instanceof QueuedXZ)) {
				return false;
			}
			return ((QueuedXZ) other).x == x && ((QueuedXZ) other).z == z;
		}

		@Override
		public int hashCode() {
			return x * 31 + z;
		}
	}

	public MapWorld(World world, File location) {
		this.world = world;
		regionMap = new TLongObjectHashMap<MapRegion>();
		queuedChunks = new PriorityQueue<QueuedXZ>(11, new Comparator<QueuedXZ>() {
			@Override
			public int compare(QueuedXZ c1, QueuedXZ c2) {
				return (c1 != null ? c1.p : 0) - (c2 != null ? c2.p : 0);
			}
		});

		String saveFolder = world.provider.getSaveFolder();
		if (saveFolder == null) {
			saveFolder = "world";
		}
		this.location = new File(location, saveFolder);
		try {
			this.location.mkdirs();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	private long getXzId(int x, int z) {
		return (x << 24) | z;
	}

	private MapRegion getRegion(int x, int z) {
		long id = getXzId(x, z);
		MapRegion region = regionMap.get(id);
		if (region == null) {
			region = new MapRegion(x, z);

			// Check in the location first
			File target = new File(location, "r" + x + "," + z + ".nbt");
			if (target.exists()) {
				try {
					FileInputStream f = new FileInputStream(target);
					byte [] data = new byte [(int) target.length()];
					f.read(data);
					f.close();

					region.readFromNBT(NBTUtils.load(data));
				} catch (FileNotFoundException e) {
					e.printStackTrace();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}

			regionMap.put(id, region);
		}
		return region;
	}

	private MapChunk getChunk(int x, int z) {
		MapRegion region = getRegion(x >> 4, z >> 4);
		return region.getChunk(x & 15, z & 15);
	}

	public boolean hasChunk(int x, int z) {
		MapRegion region = getRegion(x >> 4, z >> 4);
		return region.hasChunk(x & 15, z & 15);
	}

	public void queueChunkForUpdate(int x, int z, int priority) {
		long id = getXzId(x, z);
		queuedChunks.add(new QueuedXZ(x, z, priority));
	}

	public void queueChunkForUpdateIfEmpty(int x, int z, int priority) {
		if (!hasChunk(x, z)) {
			queueChunkForUpdate(x, z, priority);
		}
	}

	public void updateChunkInQueue() {
		if (queuedChunks.size() == 0) {
			return;
		}

		QueuedXZ q = queuedChunks.remove();
		if (q == null) {
			return;
		}

		if (!world.getChunkProvider().chunkExists(q.x, q.z)) {
			long now = (new Date()).getTime();
			if (now - lastForcedChunkLoad < 1000) {
				q.p++; // Increase priority so it gets looked at later
				queuedChunks.add(q);
				return;
			} else {
				lastForcedChunkLoad = now;
			}
		}

		updateChunk(q.x, q.z);
	}

	public void save() {
		Iterator<QueuedXZ> i = regionUpdateSet.iterator();

		while (i.hasNext()) {
			QueuedXZ id = i.next();
			i.remove();
			if (id == null) {
				continue;
			}

			MapRegion region = regionMap.get(getXzId(id.x, id.z));
			if (region == null) {
				continue;
			}

			NBTTagCompound output = new NBTTagCompound();
			region.writeToNBT(output);
			byte[] data = NBTUtils.save(output);
			File file = new File(location, "r" + id.x + "," + id.z + ".nbt");

			try {
				FileOutputStream f = new FileOutputStream(file);
				f.write(data);
				f.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}

	public int getColor(int x, int z) {
		MapChunk chunk = getChunk(x >> 4, z >> 4);
		return chunk.getColor(x & 15, z & 15);
	}

	protected void updateChunk(int x, int z) {
		MapChunk chunk = getChunk(x, z);
		chunk.update(world.getChunkFromChunkCoords(x, z));
		regionUpdateSet.add(new QueuedXZ(x >> 4, z >> 4, 0));

		// priority does not matter - see equals
		queuedChunks.remove(new QueuedXZ(x, z, 0));
	}
}