package com.comphenix.protocol.injector.packet;
import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.Map.Entry;
import javax.annotation.Nullable;
import net.sf.cglib.proxy.Factory;
import com.comphenix.protocol.reflect.FieldAccessException;
import com.comphenix.protocol.reflect.FieldUtils;
import com.comphenix.protocol.reflect.FuzzyReflection;
import com.comphenix.protocol.reflect.fuzzy.FuzzyClassContract;
import com.comphenix.protocol.reflect.fuzzy.FuzzyFieldContract;
import com.comphenix.protocol.reflect.fuzzy.FuzzyMethodContract;
import com.comphenix.protocol.utility.MinecraftReflection;
import com.comphenix.protocol.wrappers.TroveWrapper;
import com.google.common.base.Function;
import com.google.common.base.Predicate;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.collect.Multimap;
@SuppressWarnings("rawtypes")
class LegacyPacketRegistry {
private static final int MIN_SERVER_PACKETS = 5;
private static final int MIN_CLIENT_PACKETS = 5;
// Fuzzy reflection
private FuzzyReflection packetRegistry;
// The packet class to packet ID translator
private Map<Class, Integer> packetToID;
// Packet IDs to classes, grouped by whether or not they're vanilla or custom defined
private Multimap<Integer, Class> customIdToPacket;
private Map<Integer, Class> vanillaIdToPacket;
// Whether or not certain packets are sent by the client or the server
private ImmutableSet<Integer> serverPackets;
private ImmutableSet<Integer> clientPackets;
// The underlying sets
private Set<Integer> serverPacketsRef;
private Set<Integer> clientPacketsRef;
// New proxy values
private Map<Integer, Class> overwrittenPackets = new HashMap<Integer, Class>();
// Vanilla packets
private Map<Integer, Class> previousValues = new HashMap<Integer, Class>();
/**
* Initialize the registry.
*/
@SuppressWarnings({ "unchecked" })
public void initialize() {
if (packetToID == null) {
try {
Field packetsField = getPacketRegistry().getFieldByType("packetsField", Map.class);
packetToID = (Map<Class, Integer>) FieldUtils.readStaticField(packetsField, true);
} catch (IllegalArgumentException e) {
// Spigot 1.2.5 MCPC workaround
try {
packetToID = getSpigotWrapper();
} catch (Exception e2) {
// Very bad indeed
throw new IllegalArgumentException(e.getMessage() + "; Spigot workaround failed.", e2);
}
} catch (IllegalAccessException e) {
throw new RuntimeException("Unable to retrieve the packetClassToIdMap", e);
}
// Create the inverse maps
customIdToPacket = InverseMaps.inverseMultimap(packetToID, new Predicate<Map.Entry<Class, Integer>>() {
@Override
public boolean apply(@Nullable Entry<Class, Integer> entry) {
return !MinecraftReflection.isMinecraftClass(entry.getKey());
}
});
// And the vanilla pack - here we assume a unique ID to class mapping
vanillaIdToPacket = InverseMaps.inverseMap(packetToID, new Predicate<Map.Entry<Class, Integer>>() {
@Override
public boolean apply(@Nullable Entry<Class, Integer> entry) {
return MinecraftReflection.isMinecraftClass(entry.getKey());
}
});
}
initializeSets();
}
@SuppressWarnings("unchecked")
private void initializeSets() throws FieldAccessException {
if (serverPacketsRef == null || clientPacketsRef == null) {
List<Field> sets = getPacketRegistry().getFieldListByType(Set.class);
try {
if (sets.size() > 1) {
serverPacketsRef = (Set<Integer>) FieldUtils.readStaticField(sets.get(0), true);
clientPacketsRef = (Set<Integer>) FieldUtils.readStaticField(sets.get(1), true);
// Impossible
if (serverPacketsRef == null || clientPacketsRef == null)
throw new FieldAccessException("Packet sets are in an illegal state.");
// NEVER allow callers to modify the underlying sets
serverPackets = ImmutableSet.copyOf(serverPacketsRef);
clientPackets = ImmutableSet.copyOf(clientPacketsRef);
// Check sizes
if (serverPackets.size() < MIN_SERVER_PACKETS)
throw new InsufficientPacketsException("Insufficient server packets.", false, serverPackets.size());
if (clientPackets.size() < MIN_CLIENT_PACKETS)
throw new InsufficientPacketsException("Insufficient client packets.", true, clientPackets.size());
} else {
throw new FieldAccessException("Cannot retrieve packet client/server sets.");
}
} catch (IllegalAccessException e) {
throw new FieldAccessException("Cannot access field.", e);
}
} else {
// Copy over again if it has changed
if (serverPacketsRef != null && serverPacketsRef.size() != serverPackets.size())
serverPackets = ImmutableSet.copyOf(serverPacketsRef);
if (clientPacketsRef != null && clientPacketsRef.size() != clientPackets.size())
clientPackets = ImmutableSet.copyOf(clientPacketsRef);
}
}
/**
* Retrieve the packet mapping.
* @return The packet map.
*/
public Map<Class, Integer> getPacketToID() {
// Initialize it, if we haven't already
if (packetToID == null) {
initialize();
}
return packetToID;
}
private Map<Class, Integer> getSpigotWrapper() throws IllegalAccessException {
// If it talks like a duck, etc.
// Perhaps it would be nice to have a proper duck typing library as well
FuzzyClassContract mapLike = FuzzyClassContract.newBuilder().
method(FuzzyMethodContract.newBuilder().
nameExact("size").returnTypeExact(int.class)).
method(FuzzyMethodContract.newBuilder().
nameExact("put").parameterCount(2)).
method(FuzzyMethodContract.newBuilder().
nameExact("get").parameterCount(1)).
build();
Field packetsField = getPacketRegistry().getField(
FuzzyFieldContract.newBuilder().typeMatches(mapLike).build());
Object troveMap = FieldUtils.readStaticField(packetsField, true);
// Fix incorrect no entry values
TroveWrapper.transformNoEntryValue(troveMap, new Function<Integer, Integer>() {
public Integer apply(Integer value) {
if (value >= 0 && value < 256) {
// Someone forgot to set the no entry value. Let's help them.
return -1;
}
return value;
}
});
// We'll assume this a Trove map
return TroveWrapper.getDecoratedMap(troveMap);
}
/**
* Retrieve the cached fuzzy reflection instance allowing access to the packet registry.
* @return Reflected packet registry.
*/
private FuzzyReflection getPacketRegistry() {
if (packetRegistry == null)
packetRegistry = FuzzyReflection.fromClass(MinecraftReflection.getPacketClass(), true);
return packetRegistry;
}
/**
* Retrieve the injected proxy classes handlig each packet ID.
* @return Injected classes.
*/
public Map<Integer, Class> getOverwrittenPackets() {
return overwrittenPackets;
}
/**
* Retrieve the vanilla classes handling each packet ID.
* @return Vanilla classes.
*/
public Map<Integer, Class> getPreviousPackets() {
return previousValues;
}
/**
* Retrieve every known and supported server packet.
* @return An immutable set of every known server packet.
* @throws FieldAccessException If we're unable to retrieve the server packet data from Minecraft.
*/
public Set<Integer> getServerPackets() throws FieldAccessException {
initializeSets();
// Sanity check. This is impossible!
if (serverPackets != null && serverPackets.size() < MIN_SERVER_PACKETS)
throw new FieldAccessException("Server packet list is empty. Seems to be unsupported");
return serverPackets;
}
/**
* Retrieve every known and supported client packet.
* @return An immutable set of every known client packet.
* @throws FieldAccessException If we're unable to retrieve the client packet data from Minecraft.
*/
public Set<Integer> getClientPackets() throws FieldAccessException {
initializeSets();
// As above
if (clientPackets != null && clientPackets.size() < MIN_CLIENT_PACKETS)
throw new FieldAccessException("Client packet list is empty. Seems to be unsupported");
return clientPackets;
}
/**
* Retrieves the correct packet class from a given packet ID.
* @param packetID - the packet ID.
* @return The associated class.
*/
public Class getPacketClassFromID(int packetID) {
return getPacketClassFromID(packetID, false);
}
/**
* Retrieves the correct packet class from a given packet ID.
* @param packetID - the packet ID.
* @param forceVanilla - whether or not to look for vanilla classes, not injected classes.
* @return The associated class.
*/
public Class getPacketClassFromID(int packetID, boolean forceVanilla) {
Map<Integer, Class> lookup = forceVanilla ? previousValues : overwrittenPackets;
Class<?> result = null;
// Optimized lookup
if (lookup.containsKey(packetID)) {
return removeEnhancer(lookup.get(packetID), forceVanilla);
}
// Refresh lookup tables
getPacketToID();
// See if we can look for non-vanilla classes
if (!forceVanilla) {
result = Iterables.getFirst(customIdToPacket.get(packetID), null);
}
if (result == null) {
result = vanillaIdToPacket.get(packetID);
}
// See if we got it
if (result != null)
return result;
else
throw new IllegalArgumentException("The packet ID " + packetID + " is not registered.");
}
/**
* Retrieve the packet ID of a given packet.
* @param packet - the type of packet to check.
* @return The ID of the given packet.
* @throws IllegalArgumentException If this is not a valid packet.
*/
public int getPacketID(Class<?> packet) {
if (packet == null)
throw new IllegalArgumentException("Packet type class cannot be NULL.");
if (!MinecraftReflection.getPacketClass().isAssignableFrom(packet))
throw new IllegalArgumentException("Type must be a packet.");
// The registry contains both the overridden and original packets
return getPacketToID().get(packet);
}
/**
* Find the first superclass that is not a CBLib proxy object.
* @param clazz - the class whose hierachy we're going to search through.
* @param remove - whether or not to skip enhanced (proxy) classes.
* @return If remove is TRUE, the first superclass that is not a proxy.
*/
private static Class removeEnhancer(Class clazz, boolean remove) {
if (remove) {
// Get the underlying vanilla class
while (Factory.class.isAssignableFrom(clazz) && !clazz.equals(Object.class)) {
clazz = clazz.getSuperclass();
}
}
return clazz;
}
/**
* Occurs when we were unable to retrieve all the packets in the registry.
* @author Kristian
*/
public static class InsufficientPacketsException extends RuntimeException {
private static final long serialVersionUID = 1L;
private final boolean client;
private final int packetCount;
private InsufficientPacketsException(String message, boolean client, int packetCount) {
super(message);
this.client = client;
this.packetCount = packetCount;
}
public boolean isClient() {
return client;
}
public int getPacketCount() {
return packetCount;
}
}
}