001    package net.minecraftforge.common;
002    
003    import java.io.DataInputStream;
004    import java.io.File;
005    import java.io.FileInputStream;
006    import java.io.IOException;
007    import java.util.HashSet;
008    import java.util.LinkedHashSet;
009    import java.util.LinkedList;
010    import java.util.List;
011    import java.util.Map;
012    import java.util.Set;
013    import java.util.UUID;
014    import java.util.logging.Level;
015    
016    import com.google.common.cache.Cache;
017    import com.google.common.cache.CacheBuilder;
018    import com.google.common.collect.ArrayListMultimap;
019    import com.google.common.collect.BiMap;
020    import com.google.common.collect.HashBiMap;
021    import com.google.common.collect.HashMultimap;
022    import com.google.common.collect.ImmutableList;
023    import com.google.common.collect.ImmutableSet;
024    import com.google.common.collect.ImmutableSetMultimap;
025    import com.google.common.collect.LinkedHashMultimap;
026    import com.google.common.collect.ListMultimap;
027    import com.google.common.collect.Lists;
028    import com.google.common.collect.MapMaker;
029    import com.google.common.collect.Maps;
030    import com.google.common.collect.Multimap;
031    import com.google.common.collect.Multiset;
032    import com.google.common.collect.SetMultimap;
033    import com.google.common.collect.Sets;
034    import com.google.common.collect.TreeMultiset;
035    
036    import cpw.mods.fml.common.FMLLog;
037    import cpw.mods.fml.common.Loader;
038    import cpw.mods.fml.common.ModContainer;
039    
040    import net.minecraft.src.Chunk;
041    import net.minecraft.src.ChunkCoordIntPair;
042    import net.minecraft.src.CompressedStreamTools;
043    import net.minecraft.src.Entity;
044    import net.minecraft.src.EntityPlayer;
045    import net.minecraft.src.MathHelper;
046    import net.minecraft.src.NBTBase;
047    import net.minecraft.src.NBTTagCompound;
048    import net.minecraft.src.NBTTagList;
049    import net.minecraft.src.World;
050    import net.minecraft.src.WorldServer;
051    import net.minecraftforge.common.ForgeChunkManager.Ticket;
052    
053    /**
054     * Manages chunkloading for mods.
055     *
056     * The basic principle is a ticket based system.
057     * 1. Mods register a callback {@link #setForcedChunkLoadingCallback(Object, LoadingCallback)}
058     * 2. Mods ask for a ticket {@link #requestTicket(Object, World, Type)} and then hold on to that ticket.
059     * 3. Mods request chunks to stay loaded {@link #forceChunk(Ticket, ChunkCoordIntPair)} or remove chunks from force loading {@link #unforceChunk(Ticket, ChunkCoordIntPair)}.
060     * 4. When a world unloads, the tickets associated with that world are saved by the chunk manager.
061     * 5. When a world loads, saved tickets are offered to the mods associated with the tickets. The {@link Ticket#getModData()} that is set by the mod should be used to re-register
062     * chunks to stay loaded (and maybe take other actions).
063     *
064     * The chunkloading is configurable at runtime. The file "config/forgeChunkLoading.cfg" contains both default configuration for chunkloading, and a sample individual mod
065     * specific override section.
066     *
067     * @author cpw
068     *
069     */
070    public class ForgeChunkManager
071    {
072        private static int defaultMaxCount;
073        private static int defaultMaxChunks;
074        private static boolean overridesEnabled;
075    
076        private static Map<World, Multimap<String, Ticket>> tickets = new MapMaker().weakKeys().makeMap();
077        private static Map<String, Integer> ticketConstraints = Maps.newHashMap();
078        private static Map<String, Integer> chunkConstraints = Maps.newHashMap();
079    
080        private static SetMultimap<String, Ticket> playerTickets = HashMultimap.create();
081    
082        private static Map<String, LoadingCallback> callbacks = Maps.newHashMap();
083    
084        private static Map<World, SetMultimap<ChunkCoordIntPair,Ticket>> forcedChunks = new MapMaker().weakKeys().makeMap();
085        private static BiMap<UUID,Ticket> pendingEntities = HashBiMap.create();
086    
087        private static Map<World,Cache<Long, Chunk>> dormantChunkCache = new MapMaker().weakKeys().makeMap();
088    
089        private static File cfgFile;
090        private static Configuration config;
091        private static int playerTicketLength;
092        private static int dormantChunkCacheSize;
093        /**
094         * All mods requiring chunkloading need to implement this to handle the
095         * re-registration of chunk tickets at world loading time
096         *
097         * @author cpw
098         *
099         */
100        public interface LoadingCallback
101        {
102            /**
103             * Called back when tickets are loaded from the world to allow the
104             * mod to re-register the chunks associated with those tickets. The list supplied
105             * here is truncated to length prior to use. Tickets unwanted by the
106             * mod must be disposed of manually unless the mod is an OrderedLoadingCallback instance
107             * in which case, they will have been disposed of by the earlier callback.
108             *
109             * @param tickets The tickets to re-register. The list is immutable and cannot be manipulated directly. Copy it first.
110             * @param world the world
111             */
112            public void ticketsLoaded(List<Ticket> tickets, World world);
113        }
114    
115        /**
116         * This is a special LoadingCallback that can be implemented as well as the
117         * LoadingCallback to provide access to additional behaviour.
118         * Specifically, this callback will fire prior to Forge dropping excess
119         * tickets. Tickets in the returned list are presumed ordered and excess will
120         * be truncated from the returned list.
121         * This allows the mod to control not only if they actually <em>want</em> a ticket but
122         * also their preferred ticket ordering.
123         *
124         * @author cpw
125         *
126         */
127        public interface OrderedLoadingCallback extends LoadingCallback
128        {
129            /**
130             * Called back when tickets are loaded from the world to allow the
131             * mod to decide if it wants the ticket still, and prioritise overflow
132             * based on the ticket count.
133             * WARNING: You cannot force chunks in this callback, it is strictly for allowing the mod
134             * to be more selective in which tickets it wishes to preserve in an overflow situation
135             *
136             * @param tickets The tickets that you will want to select from. The list is immutable and cannot be manipulated directly. Copy it first.
137             * @param world The world
138             * @param maxTicketCount The maximum number of tickets that will be allowed.
139             * @return A list of the tickets this mod wishes to continue using. This list will be truncated
140             * to "maxTicketCount" size after the call returns and then offered to the other callback
141             * method
142             */
143            public List<Ticket> ticketsLoaded(List<Ticket> tickets, World world, int maxTicketCount);
144        }
145        public enum Type
146        {
147    
148            /**
149             * For non-entity registrations
150             */
151            NORMAL,
152            /**
153             * For entity registrations
154             */
155            ENTITY
156        }
157        public static class Ticket
158        {
159            private String modId;
160            private Type ticketType;
161            private LinkedHashSet<ChunkCoordIntPair> requestedChunks;
162            private NBTTagCompound modData;
163            private World world;
164            private int maxDepth;
165            private String entityClazz;
166            private int entityChunkX;
167            private int entityChunkZ;
168            private Entity entity;
169            private String player;
170    
171            Ticket(String modId, Type type, World world)
172            {
173                this.modId = modId;
174                this.ticketType = type;
175                this.world = world;
176                this.maxDepth = getMaxChunkDepthFor(modId);
177                this.requestedChunks = Sets.newLinkedHashSet();
178            }
179    
180            Ticket(String modId, Type type, World world, EntityPlayer player)
181            {
182                this(modId, type, world);
183                if (player != null)
184                {
185                    this.player = player.getEntityName();
186                }
187                else
188                {
189                    FMLLog.log(Level.SEVERE, "Attempt to create a player ticket without a valid player");
190                    throw new RuntimeException();
191                }
192            }
193            /**
194             * The chunk list depth can be manipulated up to the maximal grant allowed for the mod. This value is configurable. Once the maximum is reached,
195             * the least recently forced chunk, by original registration time, is removed from the forced chunk list.
196             *
197             * @param depth The new depth to set
198             */
199            public void setChunkListDepth(int depth)
200            {
201                if (depth > getMaxChunkDepthFor(modId) || (depth <= 0 && getMaxChunkDepthFor(modId) > 0))
202                {
203                    FMLLog.warning("The mod %s tried to modify the chunk ticket depth to: %d, its allowed maximum is: %d", modId, depth, getMaxChunkDepthFor(modId));
204                }
205                else
206                {
207                    this.maxDepth = depth;
208                }
209            }
210            /**
211             * Get the maximum chunk depth size
212             *
213             * @return The maximum chunk depth size
214             */
215            public int getMaxChunkListDepth()
216            {
217                return getMaxChunkDepthFor(modId);
218            }
219    
220            /**
221             * Bind the entity to the ticket for {@link Type#ENTITY} type tickets. Other types will throw a runtime exception.
222             *
223             * @param entity The entity to bind
224             */
225            public void bindEntity(Entity entity)
226            {
227                if (ticketType!=Type.ENTITY)
228                {
229                    throw new RuntimeException("Cannot bind an entity to a non-entity ticket");
230                }
231                this.entity = entity;
232            }
233    
234            /**
235             * Retrieve the {@link NBTTagCompound} that stores mod specific data for the chunk ticket.
236             * Example data to store would be a TileEntity or Block location. This is persisted with the ticket and
237             * provided to the {@link LoadingCallback} for the mod. It is recommended to use this to recover
238             * useful state information for the forced chunks.
239             *
240             * @return The custom compound tag for mods to store additional chunkloading data
241             */
242            public NBTTagCompound getModData()
243            {
244                if (this.modData == null)
245                {
246                    this.modData = new NBTTagCompound();
247                }
248                return modData;
249            }
250    
251            /**
252             * Get the entity associated with this {@link Type#ENTITY} type ticket
253             * @return
254             */
255            public Entity getEntity()
256            {
257                return entity;
258            }
259    
260            /**
261             * Is this a player associated ticket rather than a mod associated ticket?
262             *
263             * @return
264             */
265            public boolean isPlayerTicket()
266            {
267                return player != null;
268            }
269    
270            /**
271             * Get the player associated with this ticket
272             * @return
273             */
274            public String getPlayerName()
275            {
276                return player;
277            }
278        }
279    
280        static void loadWorld(World world)
281        {
282            ArrayListMultimap<String, Ticket> newTickets = ArrayListMultimap.<String, Ticket>create();
283            tickets.put(world, newTickets);
284    
285            SetMultimap<ChunkCoordIntPair,Ticket> forcedChunkMap = LinkedHashMultimap.create();
286            forcedChunks.put(world, forcedChunkMap);
287    
288            if (!(world instanceof WorldServer))
289            {
290                return;
291            }
292    
293            dormantChunkCache.put(world, CacheBuilder.newBuilder().maximumSize(dormantChunkCacheSize).<Long, Chunk>build());
294            WorldServer worldServer = (WorldServer) world;
295            File chunkDir = worldServer.getChunkSaveLocation();
296            File chunkLoaderData = new File(chunkDir, "forcedchunks.dat");
297    
298            if (chunkLoaderData.exists() && chunkLoaderData.isFile())
299            {
300                ArrayListMultimap<String, Ticket> loadedTickets = ArrayListMultimap.<String, Ticket>create();
301                ArrayListMultimap<String, Ticket> playerLoadedTickets = ArrayListMultimap.<String, Ticket>create();
302                NBTTagCompound forcedChunkData;
303                try
304                {
305                    forcedChunkData = CompressedStreamTools.read(chunkLoaderData);
306                }
307                catch (IOException e)
308                {
309                    FMLLog.log(Level.WARNING, e, "Unable to read forced chunk data at %s - it will be ignored", chunkLoaderData.getAbsolutePath());
310                    return;
311                }
312                NBTTagList ticketList = forcedChunkData.getTagList("TicketList");
313                for (int i = 0; i < ticketList.tagCount(); i++)
314                {
315                    NBTTagCompound ticketHolder = (NBTTagCompound) ticketList.tagAt(i);
316                    String modId = ticketHolder.getString("Owner");
317                    boolean isPlayer = "Forge".equals(modId);
318    
319                    if (!isPlayer && !Loader.isModLoaded(modId))
320                    {
321                        FMLLog.warning("Found chunkloading data for mod %s which is currently not available or active - it will be removed from the world save", modId);
322                        continue;
323                    }
324    
325                    if (!isPlayer && !callbacks.containsKey(modId))
326                    {
327                        FMLLog.warning("The mod %s has registered persistent chunkloading data but doesn't seem to want to be called back with it - it will be removed from the world save", modId);
328                        continue;
329                    }
330    
331                    NBTTagList tickets = ticketHolder.getTagList("Tickets");
332                    for (int j = 0; j < tickets.tagCount(); j++)
333                    {
334                        NBTTagCompound ticket = (NBTTagCompound) tickets.tagAt(j);
335                        modId = ticket.hasKey("ModId") ? ticket.getString("ModId") : modId;
336                        Type type = Type.values()[ticket.getByte("Type")];
337                        byte ticketChunkDepth = ticket.getByte("ChunkListDepth");
338                        Ticket tick = new Ticket(modId, type, world);
339                        if (ticket.hasKey("ModData"))
340                        {
341                            tick.modData = ticket.getCompoundTag("ModData");
342                        }
343                        if (ticket.hasKey("Player"))
344                        {
345                            tick.player = ticket.getString("Player");
346                            playerLoadedTickets.put(tick.modId, tick);
347                            playerTickets.put(tick.player, tick);
348                        }
349                        else
350                        {
351                            loadedTickets.put(modId, tick);
352                        }
353                        if (type == Type.ENTITY)
354                        {
355                            tick.entityChunkX = ticket.getInteger("chunkX");
356                            tick.entityChunkZ = ticket.getInteger("chunkZ");
357                            UUID uuid = new UUID(ticket.getLong("PersistentIDMSB"), ticket.getLong("PersistentIDLSB"));
358                            // add the ticket to the "pending entity" list
359                            pendingEntities.put(uuid, tick);
360                        }
361                    }
362                }
363    
364                for (Ticket tick : ImmutableSet.copyOf(pendingEntities.values()))
365                {
366                    if (tick.ticketType == Type.ENTITY && tick.entity == null)
367                    {
368                        // force the world to load the entity's chunk
369                        // the load will come back through the loadEntity method and attach the entity
370                        // to the ticket
371                        world.getChunkFromChunkCoords(tick.entityChunkX, tick.entityChunkZ);
372                    }
373                }
374                for (Ticket tick : ImmutableSet.copyOf(pendingEntities.values()))
375                {
376                    if (tick.ticketType == Type.ENTITY && tick.entity == null)
377                    {
378                        FMLLog.warning("Failed to load persistent chunkloading entity %s from store.", pendingEntities.inverse().get(tick));
379                        loadedTickets.remove(tick.modId, tick);
380                    }
381                }
382                pendingEntities.clear();
383                // send callbacks
384                for (String modId : loadedTickets.keySet())
385                {
386                    LoadingCallback loadingCallback = callbacks.get(modId);
387                    int maxTicketLength = getMaxTicketLengthFor(modId);
388                    List<Ticket> tickets = loadedTickets.get(modId);
389                    if (loadingCallback instanceof OrderedLoadingCallback)
390                    {
391                        OrderedLoadingCallback orderedLoadingCallback = (OrderedLoadingCallback) loadingCallback;
392                        tickets = orderedLoadingCallback.ticketsLoaded(ImmutableList.copyOf(tickets), world, maxTicketLength);
393                    }
394                    if (tickets.size() > maxTicketLength)
395                    {
396                        FMLLog.warning("The mod %s has too many open chunkloading tickets %d. Excess will be dropped", modId, tickets.size());
397                        tickets.subList(maxTicketLength, tickets.size()).clear();
398                    }
399                    ForgeChunkManager.tickets.get(world).putAll(modId, tickets);
400                    loadingCallback.ticketsLoaded(ImmutableList.copyOf(tickets), world);
401                }
402                for (String modId : playerLoadedTickets.keySet())
403                {
404                    LoadingCallback loadingCallback = callbacks.get(modId);
405                    List<Ticket> tickets = playerLoadedTickets.get(modId);
406                    ForgeChunkManager.tickets.get(world).putAll("Forge", tickets);
407                    loadingCallback.ticketsLoaded(ImmutableList.copyOf(tickets), world);
408                }
409            }
410        }
411    
412        /**
413         * Set a chunkloading callback for the supplied mod object
414         *
415         * @param mod  The mod instance registering the callback
416         * @param callback The code to call back when forced chunks are loaded
417         */
418        public static void setForcedChunkLoadingCallback(Object mod, LoadingCallback callback)
419        {
420            ModContainer container = getContainer(mod);
421            if (container == null)
422            {
423                FMLLog.warning("Unable to register a callback for an unknown mod %s (%s : %x)", mod, mod.getClass().getName(), System.identityHashCode(mod));
424                return;
425            }
426    
427            callbacks.put(container.getModId(), callback);
428        }
429    
430        /**
431         * Discover the available tickets for the mod in the world
432         *
433         * @param mod The mod that will own the tickets
434         * @param world The world
435         * @return The count of tickets left for the mod in the supplied world
436         */
437        public static int ticketCountAvailableFor(Object mod, World world)
438        {
439            ModContainer container = getContainer(mod);
440            if (container!=null)
441            {
442                String modId = container.getModId();
443                int allowedCount = getMaxTicketLengthFor(modId);
444                return allowedCount - tickets.get(world).get(modId).size();
445            }
446            else
447            {
448                return 0;
449            }
450        }
451    
452        private static ModContainer getContainer(Object mod)
453        {
454            ModContainer container = Loader.instance().getModObjectList().inverse().get(mod);
455            return container;
456        }
457    
458        private static int getMaxTicketLengthFor(String modId)
459        {
460            int allowedCount = ticketConstraints.containsKey(modId) && overridesEnabled ? ticketConstraints.get(modId) : defaultMaxCount;
461            return allowedCount;
462        }
463    
464        private static int getMaxChunkDepthFor(String modId)
465        {
466            int allowedCount = chunkConstraints.containsKey(modId) && overridesEnabled ? chunkConstraints.get(modId) : defaultMaxChunks;
467            return allowedCount;
468        }
469    
470        public static Ticket requestPlayerTicket(Object mod, EntityPlayer player, World world, Type type)
471        {
472            ModContainer mc = getContainer(mod);
473            if (mc == null)
474            {
475                FMLLog.log(Level.SEVERE, "Failed to locate the container for mod instance %s (%s : %x)", mod, mod.getClass().getName(), System.identityHashCode(mod));
476                return null;
477            }
478            if (playerTickets.get(player.getEntityName()).size()>playerTicketLength)
479            {
480                FMLLog.warning("Unable to assign further chunkloading tickets to player %s (on behalf of mod %s)", player.getEntityName(), mc.getModId());
481                return null;
482            }
483            Ticket ticket = new Ticket(mc.getModId(),type,world,player);
484            playerTickets.put(player.getEntityName(), ticket);
485            tickets.get(world).put("Forge", ticket);
486            return ticket;
487        }
488        /**
489         * Request a chunkloading ticket of the appropriate type for the supplied mod
490         *
491         * @param mod The mod requesting a ticket
492         * @param world The world in which it is requesting the ticket
493         * @param type The type of ticket
494         * @return A ticket with which to register chunks for loading, or null if no further tickets are available
495         */
496        public static Ticket requestTicket(Object mod, World world, Type type)
497        {
498            ModContainer container = getContainer(mod);
499            if (container == null)
500            {
501                FMLLog.log(Level.SEVERE, "Failed to locate the container for mod instance %s (%s : %x)", mod, mod.getClass().getName(), System.identityHashCode(mod));
502                return null;
503            }
504            String modId = container.getModId();
505            if (!callbacks.containsKey(modId))
506            {
507                FMLLog.severe("The mod %s has attempted to request a ticket without a listener in place", modId);
508                throw new RuntimeException("Invalid ticket request");
509            }
510    
511            int allowedCount = ticketConstraints.containsKey(modId) ? ticketConstraints.get(modId) : defaultMaxCount;
512    
513            if (tickets.get(world).get(modId).size() >= allowedCount)
514            {
515                FMLLog.info("The mod %s has attempted to allocate a chunkloading ticket beyond it's currently allocated maximum : %d", modId, allowedCount);
516                return null;
517            }
518            Ticket ticket = new Ticket(modId, type, world);
519            tickets.get(world).put(modId, ticket);
520    
521            return ticket;
522        }
523    
524        /**
525         * Release the ticket back to the system. This will also unforce any chunks held by the ticket so that they can be unloaded and/or stop ticking.
526         *
527         * @param ticket The ticket to release
528         */
529        public static void releaseTicket(Ticket ticket)
530        {
531            if (ticket == null)
532            {
533                return;
534            }
535            if (ticket.isPlayerTicket() ? !playerTickets.containsValue(ticket) : !tickets.get(ticket.world).containsEntry(ticket.modId, ticket))
536            {
537                return;
538            }
539            if (ticket.requestedChunks!=null)
540            {
541                for (ChunkCoordIntPair chunk : ImmutableSet.copyOf(ticket.requestedChunks))
542                {
543                    unforceChunk(ticket, chunk);
544                }
545            }
546            if (ticket.isPlayerTicket())
547            {
548                playerTickets.remove(ticket.player, ticket);
549                tickets.get(ticket.world).remove("Forge",ticket);
550            }
551            else
552            {
553                tickets.get(ticket.world).remove(ticket.modId, ticket);
554            }
555        }
556    
557        /**
558         * Force the supplied chunk coordinate to be loaded by the supplied ticket. If the ticket's {@link Ticket#maxDepth} is exceeded, the least
559         * recently registered chunk is unforced and may be unloaded.
560         * It is safe to force the chunk several times for a ticket, it will not generate duplication or change the ordering.
561         *
562         * @param ticket The ticket registering the chunk
563         * @param chunk The chunk to force
564         */
565        public static void forceChunk(Ticket ticket, ChunkCoordIntPair chunk)
566        {
567            if (ticket == null || chunk == null)
568            {
569                return;
570            }
571            if (ticket.ticketType == Type.ENTITY && ticket.entity == null)
572            {
573                throw new RuntimeException("Attempted to use an entity ticket to force a chunk, without an entity");
574            }
575            if (ticket.isPlayerTicket() ? !playerTickets.containsValue(ticket) : !tickets.get(ticket.world).containsEntry(ticket.modId, ticket))
576            {
577                FMLLog.severe("The mod %s attempted to force load a chunk with an invalid ticket. This is not permitted.", ticket.modId);
578                return;
579            }
580            ticket.requestedChunks.add(chunk);
581            forcedChunks.get(ticket.world).put(chunk, ticket);
582            if (ticket.maxDepth > 0 && ticket.requestedChunks.size() > ticket.maxDepth)
583            {
584                ChunkCoordIntPair removed = ticket.requestedChunks.iterator().next();
585                unforceChunk(ticket,removed);
586            }
587        }
588    
589        /**
590         * Reorganize the internal chunk list so that the chunk supplied is at the *end* of the list
591         * This helps if you wish to guarantee a certain "automatic unload ordering" for the chunks
592         * in the ticket list
593         *
594         * @param ticket The ticket holding the chunk list
595         * @param chunk The chunk you wish to push to the end (so that it would be unloaded last)
596         */
597        public static void reorderChunk(Ticket ticket, ChunkCoordIntPair chunk)
598        {
599            if (ticket == null || chunk == null || !ticket.requestedChunks.contains(chunk))
600            {
601                return;
602            }
603            ticket.requestedChunks.remove(chunk);
604            ticket.requestedChunks.add(chunk);
605        }
606        /**
607         * Unforce the supplied chunk, allowing it to be unloaded and stop ticking.
608         *
609         * @param ticket The ticket holding the chunk
610         * @param chunk The chunk to unforce
611         */
612        public static void unforceChunk(Ticket ticket, ChunkCoordIntPair chunk)
613        {
614            if (ticket == null || chunk == null)
615            {
616                return;
617            }
618            ticket.requestedChunks.remove(chunk);
619            forcedChunks.get(ticket.world).remove(chunk, ticket);
620        }
621    
622        static void loadConfiguration()
623        {
624            for (String mod : config.categories.keySet())
625            {
626                if (mod.equals("Forge") || mod.equals("defaults"))
627                {
628                    continue;
629                }
630                Property modTC = config.get(mod, "maximumTicketCount", 200);
631                Property modCPT = config.get(mod, "maximumChunksPerTicket", 25);
632                ticketConstraints.put(mod, modTC.getInt(200));
633                chunkConstraints.put(mod, modCPT.getInt(25));
634            }
635            config.save();
636        }
637    
638        /**
639         * The list of persistent chunks in the world. This set is immutable.
640         * @param world
641         * @return
642         */
643        public static SetMultimap<ChunkCoordIntPair, Ticket> getPersistentChunksFor(World world)
644        {
645            return forcedChunks.containsKey(world) ? ImmutableSetMultimap.copyOf(forcedChunks.get(world)) : ImmutableSetMultimap.<ChunkCoordIntPair,Ticket>of();
646        }
647    
648        static void saveWorld(World world)
649        {
650            // only persist persistent worlds
651            if (!(world instanceof WorldServer)) { return; }
652            WorldServer worldServer = (WorldServer) world;
653            File chunkDir = worldServer.getChunkSaveLocation();
654            File chunkLoaderData = new File(chunkDir, "forcedchunks.dat");
655    
656            NBTTagCompound forcedChunkData = new NBTTagCompound();
657            NBTTagList ticketList = new NBTTagList();
658            forcedChunkData.setTag("TicketList", ticketList);
659    
660            Multimap<String, Ticket> ticketSet = tickets.get(worldServer);
661            for (String modId : ticketSet.keySet())
662            {
663                NBTTagCompound ticketHolder = new NBTTagCompound();
664                ticketList.appendTag(ticketHolder);
665    
666                ticketHolder.setString("Owner", modId);
667                NBTTagList tickets = new NBTTagList();
668                ticketHolder.setTag("Tickets", tickets);
669    
670                for (Ticket tick : ticketSet.get(modId))
671                {
672                    NBTTagCompound ticket = new NBTTagCompound();
673                    ticket.setByte("Type", (byte) tick.ticketType.ordinal());
674                    ticket.setByte("ChunkListDepth", (byte) tick.maxDepth);
675                    if (tick.isPlayerTicket())
676                    {
677                        ticket.setString("ModId", tick.modId);
678                        ticket.setString("Player", tick.player);
679                    }
680                    if (tick.modData != null)
681                    {
682                        ticket.setCompoundTag("ModData", tick.modData);
683                    }
684                    if (tick.ticketType == Type.ENTITY && tick.entity != null)
685                    {
686                        ticket.setInteger("chunkX", MathHelper.floor_double(tick.entity.chunkCoordX));
687                        ticket.setInteger("chunkZ", MathHelper.floor_double(tick.entity.chunkCoordZ));
688                        ticket.setLong("PersistentIDMSB", tick.entity.getPersistentID().getMostSignificantBits());
689                        ticket.setLong("PersistentIDLSB", tick.entity.getPersistentID().getLeastSignificantBits());
690                        tickets.appendTag(ticket);
691                    }
692                    else if (tick.ticketType != Type.ENTITY)
693                    {
694                        tickets.appendTag(ticket);
695                    }
696                }
697            }
698            try
699            {
700                CompressedStreamTools.write(forcedChunkData, chunkLoaderData);
701            }
702            catch (IOException e)
703            {
704                FMLLog.log(Level.WARNING, e, "Unable to write forced chunk data to %s - chunkloading won't work", chunkLoaderData.getAbsolutePath());
705                return;
706            }
707        }
708    
709        static void loadEntity(Entity entity)
710        {
711            UUID id = entity.getPersistentID();
712            Ticket tick = pendingEntities.get(id);
713            if (tick != null)
714            {
715                tick.bindEntity(entity);
716                pendingEntities.remove(id);
717            }
718        }
719    
720        public static void putDormantChunk(long coords, Chunk chunk)
721        {
722            Cache<Long, Chunk> cache = dormantChunkCache.get(chunk.worldObj);
723            if (cache != null)
724            {
725                cache.put(coords, chunk);
726            }
727        }
728    
729        public static Chunk fetchDormantChunk(long coords, World world)
730        {
731            Cache<Long, Chunk> cache = dormantChunkCache.get(world);
732            return cache == null ? null : cache.getIfPresent(coords);
733        }
734    
735        static void captureConfig(File configDir)
736        {
737            cfgFile = new File(configDir,"forgeChunkLoading.cfg");
738            config = new Configuration(cfgFile, true);
739            config.categories.clear();
740            try
741            {
742                config.load();
743            }
744            catch (Exception e)
745            {
746                File dest = new File(cfgFile.getParentFile(),"forgeChunkLoading.cfg.bak");
747                if (dest.exists())
748                {
749                    dest.delete();
750                }
751                cfgFile.renameTo(dest);
752                FMLLog.log(Level.SEVERE, e, "A critical error occured reading the forgeChunkLoading.cfg file, defaults will be used - the invalid file is backed up at forgeChunkLoading.cfg.bak");
753            }
754            config.addCustomCategoryComment("defaults", "Default configuration for forge chunk loading control");
755            Property maxTicketCount = config.get("defaults", "maximumTicketCount", 200);
756            maxTicketCount.comment = "The default maximum ticket count for a mod which does not have an override\n" +
757                        "in this file. This is the number of chunk loading requests a mod is allowed to make.";
758            defaultMaxCount = maxTicketCount.getInt(200);
759    
760            Property maxChunks = config.get("defaults", "maximumChunksPerTicket", 25);
761            maxChunks.comment = "The default maximum number of chunks a mod can force, per ticket, \n" +
762                        "for a mod without an override. This is the maximum number of chunks a single ticket can force.";
763            defaultMaxChunks = maxChunks.getInt(25);
764    
765            Property playerTicketCount = config.get("defaults", "playetTicketCount", 500);
766            playerTicketCount.comment = "The number of tickets a player can be assigned instead of a mod. This is shared across all mods and it is up to the mods to use it.";
767            playerTicketLength = playerTicketCount.getInt(500);
768    
769            Property dormantChunkCacheSizeProperty = config.get("defaults", "dormantChunkCacheSize", 0);
770            dormantChunkCacheSizeProperty.comment = "Unloaded chunks can first be kept in a dormant cache for quicker\n" +
771                        "loading times. Specify the size of that cache here";
772            dormantChunkCacheSize = dormantChunkCacheSizeProperty.getInt(0);
773            FMLLog.info("Configured a dormant chunk cache size of %d", dormantChunkCacheSizeProperty.getInt(0));
774    
775            Property modOverridesEnabled = config.get("defaults", "enabled", true);
776            modOverridesEnabled.comment = "Are mod overrides enabled?";
777            overridesEnabled = modOverridesEnabled.getBoolean(true);
778    
779            config.addCustomCategoryComment("Forge", "Sample mod specific control section.\n" +
780                    "Copy this section and rename the with the modid for the mod you wish to override.\n" +
781                    "A value of zero in either entry effectively disables any chunkloading capabilities\n" +
782                    "for that mod");
783    
784            Property sampleTC = config.get("Forge", "maximumTicketCount", 200);
785            sampleTC.comment = "Maximum ticket count for the mod. Zero disables chunkloading capabilities.";
786            sampleTC = config.get("Forge", "maximumChunksPerTicket", 25);
787            sampleTC.comment = "Maximum chunks per ticket for the mod.";
788            for (String mod : config.categories.keySet())
789            {
790                if (mod.equals("Forge") || mod.equals("defaults"))
791                {
792                    continue;
793                }
794                Property modTC = config.get(mod, "maximumTicketCount", 200);
795                Property modCPT = config.get(mod, "maximumChunksPerTicket", 25);
796            }
797        }
798    
799    
800        public static Map<String,Property> getConfigMapFor(Object mod)
801        {
802            ModContainer container = getContainer(mod);
803            if (container != null)
804            {
805                Map<String, Property> map = config.categories.get(container.getModId());
806                if (map == null)
807                {
808                    map = Maps.newHashMap();
809                    config.categories.put(container.getModId(), map);
810                }
811                return map;
812            }
813    
814            return null;
815        }
816    
817        public static void addConfigProperty(Object mod, String propertyName, String value, Property.Type type)
818        {
819            ModContainer container = getContainer(mod);
820            if (container != null)
821            {
822                Map<String, Property> props = config.categories.get(container.getModId());
823                props.put(propertyName, new Property(propertyName, value, type));
824            }
825        }
826    }