Paper/nms-patches/PlayerConnection.patch

--- a/net/minecraft/server/PlayerConnection.java
+++ b/net/minecraft/server/PlayerConnection.java
@@ -15,6 +15,49 @@
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
+// CraftBukkit start
+import java.util.HashSet;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
+import org.bukkit.Location;
+import org.bukkit.craftbukkit.entity.CraftPlayer;
+import org.bukkit.craftbukkit.event.CraftEventFactory;
+import org.bukkit.craftbukkit.inventory.CraftInventoryView;
+import org.bukkit.craftbukkit.inventory.CraftItemStack;
+import org.bukkit.craftbukkit.util.CraftChatMessage;
+import org.bukkit.craftbukkit.util.LazyPlayerSet;
+import org.bukkit.craftbukkit.util.Waitable;
+import org.bukkit.entity.Player;
+import org.bukkit.event.Event;
+import org.bukkit.event.block.Action;
+import org.bukkit.event.block.SignChangeEvent;
+import org.bukkit.event.inventory.ClickType;
+import org.bukkit.event.inventory.CraftItemEvent;
+import org.bukkit.event.inventory.InventoryAction;
+import org.bukkit.event.inventory.InventoryClickEvent;
+import org.bukkit.event.inventory.InventoryCreativeEvent;
+import org.bukkit.event.inventory.InventoryType.SlotType;
+import org.bukkit.event.player.AsyncPlayerChatEvent;
+import org.bukkit.event.player.PlayerAnimationEvent;
+import org.bukkit.event.player.PlayerChatEvent;
+import org.bukkit.event.player.PlayerCommandPreprocessEvent;
+import org.bukkit.event.player.PlayerInteractAtEntityEvent;
+import org.bukkit.event.player.PlayerInteractEntityEvent;
+import org.bukkit.event.player.PlayerItemHeldEvent;
+import org.bukkit.event.player.PlayerKickEvent;
+import org.bukkit.event.player.PlayerMoveEvent;
+import org.bukkit.event.player.PlayerResourcePackStatusEvent;
+import org.bukkit.event.player.PlayerSwapHandItemsEvent;
+import org.bukkit.event.player.PlayerTeleportEvent;
+import org.bukkit.event.player.PlayerToggleFlightEvent;
+import org.bukkit.event.player.PlayerToggleSneakEvent;
+import org.bukkit.event.player.PlayerToggleSprintEvent;
+import org.bukkit.inventory.CraftingInventory;
+import org.bukkit.inventory.EquipmentSlot;
+import org.bukkit.inventory.InventoryView;
+import org.bukkit.util.NumberConversions;
+// CraftBukkit end
+
 public class PlayerConnection implements PacketListenerPlayIn, ITickable {
 
     private static final Logger LOGGER = LogManager.getLogger();
@@ -25,7 +68,10 @@
     private int f;
     private long g;
     private long h;
-    private int chatThrottle;
+    // CraftBukkit start - multithreaded fields
+    private volatile int chatThrottle;
+    private static final AtomicIntegerFieldUpdater chatSpamField = AtomicIntegerFieldUpdater.newUpdater(PlayerConnection.class, "chatThrottle");
+    // CraftBukkit end
     private int j;
     private final IntHashMap<Short> k = new IntHashMap();
     private double l;
@@ -50,6 +96,7 @@
     private int E;
     private int receivedMovePackets;
     private int processedMovePackets;
+    private boolean processedDisconnect; // CraftBukkit - Added
 
     public PlayerConnection(MinecraftServer minecraftserver, NetworkManager networkmanager, EntityPlayer entityplayer) {
         this.minecraftServer = minecraftserver;
@@ -57,7 +104,32 @@
         networkmanager.setPacketListener(this);
         this.player = entityplayer;
         entityplayer.playerConnection = this;
+
+        // CraftBukkit start - add fields and methods
+        this.server = minecraftserver.server;
+    }
+
+    private final org.bukkit.craftbukkit.CraftServer server;
+    private int lastTick = MinecraftServer.currentTick;
+    private int allowedPlayerTicks = 1;
+    private int lastDropTick = MinecraftServer.currentTick;
+    private int dropCount = 0;
+    private static final int SURVIVAL_PLACE_DISTANCE_SQUARED = 6 * 6;
+    private static final int CREATIVE_PLACE_DISTANCE_SQUARED = 7 * 7;
+
+    // Get position of last block hit for BlockDamageLevel.STOPPED
+    private double lastPosX = Double.MAX_VALUE;
+    private double lastPosY = Double.MAX_VALUE;
+    private double lastPosZ = Double.MAX_VALUE;
+    private float lastPitch = Float.MAX_VALUE;
+    private float lastYaw = Float.MAX_VALUE;
+    private boolean justTeleported = false;
+
+    public CraftPlayer getPlayer() {
+        return (this.player == null) ? null : (CraftPlayer) this.player.getBukkitEntity();
     }
+    private final static HashSet<Integer> invalidItems = new HashSet<Integer>(java.util.Arrays.asList(8, 9, 10, 11, 26, 34, 36, 43, 51, 52, 55, 59, 62, 63, 64, 68, 71, 74, 75, 83, 90, 92, 93, 94, 104, 105, 115, 117, 118, 119, 125, 127, 132, 140, 141, 142, 144)); // TODO: Check after every update.
+    // CraftBukkit end
 
     public void F_() {
         this.syncPosition();
@@ -109,15 +181,21 @@
         }
 
         this.minecraftServer.methodProfiler.b();
+        // CraftBukkit start
+        for (int spam; (spam = this.chatThrottle) > 0 && !chatSpamField.compareAndSet(this, spam, spam - 1); ) ;
+        /* Use thread-safe field access instead
         if (this.chatThrottle > 0) {
             --this.chatThrottle;
         }
+        */
+        // CraftBukkit end
 
         if (this.j > 0) {
             --this.j;
         }
 
         if (this.player.I() > 0L && this.minecraftServer.getIdleTimeout() > 0 && MinecraftServer.aw() - this.player.I() > (long) (this.minecraftServer.getIdleTimeout() * 1000 * 60)) {
+            this.player.resetIdleTimer(); // CraftBukkit - SPIGOT-854
             this.disconnect("You have been idle for too long!");
         }
 
@@ -137,19 +215,40 @@
     }
 
     public void disconnect(String s) {
+        // CraftBukkit start - fire PlayerKickEvent
+        if (this.processedDisconnect) {
+            return;
+        }
+        String leaveMessage = EnumChatFormat.YELLOW + this.player.getName() + " left the game.";
+
+        PlayerKickEvent event = new PlayerKickEvent(this.server.getPlayer(this.player), s, leaveMessage);
+
+        if (this.server.getServer().isRunning()) {
+            this.server.getPluginManager().callEvent(event);
+        }
+
+        if (event.isCancelled()) {
+            // Do not kick the player
+            return;
+        }
+        // Send the possibly modified leave message
+        s = event.getReason();
+        // CraftBukkit end
         final ChatComponentText chatcomponenttext = new ChatComponentText(s);
 
         this.networkManager.sendPacket(new PacketPlayOutKickDisconnect(chatcomponenttext), new GenericFutureListener() {
-            public void operationComplete(Future<? super Void> future) throws Exception {
+            public void operationComplete(Future future) throws Exception { // CraftBukkit - decompile error
                 PlayerConnection.this.networkManager.close(chatcomponenttext);
             }
         }, new GenericFutureListener[0]);
+        this.a(chatcomponenttext); // CraftBukkit - fire quit instantly
         this.networkManager.stopReading();
-        Futures.getUnchecked(this.minecraftServer.postToMainThread(new Runnable() {
+        // CraftBukkit - Don't wait
+        this.minecraftServer.postToMainThread(new Runnable() {
             public void run() {
                 PlayerConnection.this.networkManager.handleDisconnection();
             }
-        }));
+        });
     }
 
     public void a(PacketPlayInSteerVehicle packetplayinsteervehicle) {
@@ -188,7 +287,34 @@
                 double d9 = entity.motX * entity.motX + entity.motY * entity.motY + entity.motZ * entity.motZ;
                 double d10 = d6 * d6 + d7 * d7 + d8 * d8;
 
-                if (d10 - d9 > 100.0D && (!this.minecraftServer.R() || !this.minecraftServer.Q().equals(entity.getName()))) {
+
+                // CraftBukkit start - handle custom speeds and skipped ticks
+                this.allowedPlayerTicks += (System.currentTimeMillis() / 50) - this.lastTick;
+                this.allowedPlayerTicks = Math.max(this.allowedPlayerTicks, 1);
+                this.lastTick = (int) (System.currentTimeMillis() / 50);
+
+                ++this.receivedMovePackets;
+                int i = this.receivedMovePackets - this.processedMovePackets;
+                if (i > Math.max(this.allowedPlayerTicks, 5)) {
+                    PlayerConnection.LOGGER.debug(this.player.getName() + " is sending move packets too frequently (" + i + " packets since last tick)");
+                    i = 1;
+                }
+
+                if (d10 > 0) {
+                    allowedPlayerTicks -= 1;
+                } else {
+                    allowedPlayerTicks = 20;
+                }
+                float speed;
+                if (player.abilities.isFlying) {
+                    speed = player.abilities.flySpeed * 20f;
+                } else {
+                    speed = player.abilities.walkSpeed * 10f;
+                }
+                speed *= 2f; // TODO: Get the speed of the vehicle instead of the player
+
+                if (d10 - d9 > Math.max(100.0D, Math.pow((double) (10.0F * (float) i * speed), 2)) && (!this.minecraftServer.R() || !this.minecraftServer.Q().equals(entity.getName()))) {
+                // CraftBukkit end
                     PlayerConnection.LOGGER.warn("{} (vehicle of {}) moved too quickly! {},{},{}", new Object[] { entity.getName(), this.player.getName(), Double.valueOf(d6), Double.valueOf(d7), Double.valueOf(d8)});
                     this.networkManager.sendPacket(new PacketPlayOutVehicleMove(entity));
                     return;
@@ -226,6 +352,62 @@
                     return;
                 }
 
+                // CraftBukkit start - fire PlayerMoveEvent
+                Player player = this.getPlayer();
+                Location from = new Location(player.getWorld(), lastPosX, lastPosY, lastPosZ, lastYaw, lastPitch); // Get the Players previous Event location.
+                Location to = player.getLocation().clone(); // Start off the To location as the Players current location.
+
+                // If the packet contains movement information then we update the To location with the correct XYZ.
+                to.setX(packetplayinvehiclemove.getX());
+                to.setY(packetplayinvehiclemove.getY());
+                to.setZ(packetplayinvehiclemove.getZ());
+
+
+                // If the packet contains look information then we update the To location with the correct Yaw & Pitch.
+                to.setYaw(packetplayinvehiclemove.getYaw());
+                to.setPitch(packetplayinvehiclemove.getPitch());
+
+                // Prevent 40 event-calls for less than a single pixel of movement >.>
+                double delta = Math.pow(this.lastPosX - to.getX(), 2) + Math.pow(this.lastPosY - to.getY(), 2) + Math.pow(this.lastPosZ - to.getZ(), 2);
+                float deltaAngle = Math.abs(this.lastYaw - to.getYaw()) + Math.abs(this.lastPitch - to.getPitch());
+
+                if ((delta > 1f / 256 || deltaAngle > 10f) && !this.player.isFrozen()) {
+                    this.lastPosX = to.getX();
+                    this.lastPosY = to.getY();
+                    this.lastPosZ = to.getZ();
+                    this.lastYaw = to.getYaw();
+                    this.lastPitch = to.getPitch();
+
+                    // Skip the first time we do this
+                    if (from.getX() != Double.MAX_VALUE) {
+                        Location oldTo = to.clone();
+                        PlayerMoveEvent event = new PlayerMoveEvent(player, from, to);
+                        this.server.getPluginManager().callEvent(event);
+
+                        // If the event is cancelled we move the player back to their old location.
+                        if (event.isCancelled()) {
+                            teleport(from);
+                            return;
+                        }
+
+                        // If a Plugin has changed the To destination then we teleport the Player
+                        // there to avoid any 'Moved wrongly' or 'Moved too quickly' errors.
+                        // We only do this if the Event was not cancelled.
+                        if (!oldTo.equals(event.getTo()) && !event.isCancelled()) {
+                            this.player.getBukkitEntity().teleport(event.getTo(), PlayerTeleportEvent.TeleportCause.UNKNOWN);
+                            return;
+                        }
+
+                        // Check to see if the Players Location has some how changed during the call of the event.
+                        // This can happen due to a plugin teleporting the player instead of using .setTo()
+                        if (!from.equals(this.getPlayer().getLocation()) && this.justTeleported) {
+                            this.justTeleported = false;
+                            return;
+                        }
+                    }
+                }
+                // CraftBukkit end
+
                 this.minecraftServer.getPlayerList().d(this.player);
                 this.player.checkMovement(this.player.locX - d0, this.player.locY - d1, this.player.locZ - d2);
                 this.D = d11 >= -0.03125D && !this.minecraftServer.getAllowFlight() && !worldserver.d(entity.getBoundingBox().g(0.0625D).b(0.0D, -0.55D, 0.0D));
@@ -260,7 +442,7 @@
         } else {
             WorldServer worldserver = this.minecraftServer.getWorldServer(this.player.dimension);
 
-            if (!this.player.viewingCredits) {
+            if (!this.player.viewingCredits && !this.player.isFrozen()) { // CraftBukkit
                 if (this.e == 0) {
                     this.syncPosition();
                 }
@@ -270,13 +452,21 @@
                         this.A = this.e;
                         this.a(this.teleportPos.x, this.teleportPos.y, this.teleportPos.z, this.player.yaw, this.player.pitch);
                     }
-
+                    this.allowedPlayerTicks = 20; // CraftBukkit
                 } else {
                     this.A = this.e;
                     if (this.player.isPassenger()) {
                         this.player.setLocation(this.player.locX, this.player.locY, this.player.locZ, packetplayinflying.a(this.player.yaw), packetplayinflying.b(this.player.pitch));
                         this.minecraftServer.getPlayerList().d(this.player);
+                        this.allowedPlayerTicks = 20; // CraftBukkit
                     } else {
+                        // CraftBukkit - Make sure the move is valid but then reset it for plugins to modify
+                        double prevX = player.locX;
+                        double prevY = player.locY;
+                        double prevZ = player.locZ;
+                        float prevYaw = player.yaw;
+                        float prevPitch = player.pitch;
+                        // CraftBukkit end
                         double d0 = this.player.locX;
                         double d1 = this.player.locY;
                         double d2 = this.player.locZ;
@@ -295,15 +485,33 @@
                         ++this.receivedMovePackets;
                         int i = this.receivedMovePackets - this.processedMovePackets;
 
-                        if (i > 5) {
+                        // CraftBukkit start - handle custom speeds and skipped ticks
+                        this.allowedPlayerTicks += (System.currentTimeMillis() / 50) - this.lastTick;
+                        this.allowedPlayerTicks = Math.max(this.allowedPlayerTicks, 1);
+                        this.lastTick = (int) (System.currentTimeMillis() / 50);
+
+                        if (i > Math.max(this.allowedPlayerTicks, 5)) {
                             PlayerConnection.LOGGER.debug("{} is sending move packets too frequently ({} packets since last tick)", new Object[] { this.player.getName(), Integer.valueOf(i)});
                             i = 1;
                         }
 
+                        if (packetplayinflying.hasLook || d11 > 0) {
+                            allowedPlayerTicks -= 1;
+                        } else {
+                            allowedPlayerTicks = 20;
+                        }
+                        float speed;
+                        if (player.abilities.isFlying) {
+                            speed = player.abilities.flySpeed * 20f;
+                        } else {
+                            speed = player.abilities.walkSpeed * 10f;
+                        }
+
                         if (!this.player.K() && (!this.player.x().getGameRules().getBoolean("disableElytraMovementCheck") || !this.player.cH())) {
                             float f2 = this.player.cH() ? 300.0F : 100.0F;
 
-                            if (d11 - d10 > (double) (f2 * (float) i) && (!this.minecraftServer.R() || !this.minecraftServer.Q().equals(this.player.getName()))) {
+                            if (d11 - d10 > Math.max(f2, Math.pow((double) (10.0F * (float) i * speed), 2)) && (!this.minecraftServer.R() || !this.minecraftServer.Q().equals(this.player.getName()))) {
+                        // CraftBukkit end
                                 PlayerConnection.LOGGER.warn("{} moved too quickly! {},{},{}", new Object[] { this.player.getName(), Double.valueOf(d7), Double.valueOf(d8), Double.valueOf(d9)});
                                 this.a(this.player.locX, this.player.locY, this.player.locZ, this.player.yaw, this.player.pitch);
                                 return;
@@ -349,6 +557,69 @@
                             }
                         }
 
+                        // CraftBukkit start - fire PlayerMoveEvent
+                        // Rest to old location first
+                        this.player.setLocation(prevX, prevY, prevZ, prevYaw, prevPitch);
+
+                        Player player = this.getPlayer();
+                        Location from = new Location(player.getWorld(), lastPosX, lastPosY, lastPosZ, lastYaw, lastPitch); // Get the Players previous Event location.
+                        Location to = player.getLocation().clone(); // Start off the To location as the Players current location.
+
+                        // If the packet contains movement information then we update the To location with the correct XYZ.
+                        if (packetplayinflying.hasPos) {
+                            to.setX(packetplayinflying.x);
+                            to.setY(packetplayinflying.y);
+                            to.setZ(packetplayinflying.z);
+                        }
+
+                        // If the packet contains look information then we update the To location with the correct Yaw & Pitch.
+                        if (packetplayinflying.hasLook) {
+                            to.setYaw(packetplayinflying.yaw);
+                            to.setPitch(packetplayinflying.pitch);
+                        }
+
+                        // Prevent 40 event-calls for less than a single pixel of movement >.>
+                        double delta = Math.pow(this.lastPosX - to.getX(), 2) + Math.pow(this.lastPosY - to.getY(), 2) + Math.pow(this.lastPosZ - to.getZ(), 2);
+                        float deltaAngle = Math.abs(this.lastYaw - to.getYaw()) + Math.abs(this.lastPitch - to.getPitch());
+
+                        if ((delta > 1f / 256 || deltaAngle > 10f) && !this.player.isFrozen()) {
+                            this.lastPosX = to.getX();
+                            this.lastPosY = to.getY();
+                            this.lastPosZ = to.getZ();
+                            this.lastYaw = to.getYaw();
+                            this.lastPitch = to.getPitch();
+
+                            // Skip the first time we do this
+                            if (from.getX() != Double.MAX_VALUE) {
+                                Location oldTo = to.clone();
+                                PlayerMoveEvent event = new PlayerMoveEvent(player, from, to);
+                                this.server.getPluginManager().callEvent(event);
+
+                                // If the event is cancelled we move the player back to their old location.
+                                if (event.isCancelled()) {
+                                    teleport(from);
+                                    return;
+                                }
+
+                                // If a Plugin has changed the To destination then we teleport the Player
+                                // there to avoid any 'Moved wrongly' or 'Moved too quickly' errors.
+                                // We only do this if the Event was not cancelled.
+                                if (!oldTo.equals(event.getTo()) && !event.isCancelled()) {
+                                    this.player.getBukkitEntity().teleport(event.getTo(), PlayerTeleportEvent.TeleportCause.UNKNOWN);
+                                    return;
+                                }
+
+                                // Check to see if the Players Location has some how changed during the call of the event.
+                                // This can happen due to a plugin teleporting the player instead of using .setTo()
+                                if (!from.equals(this.getPlayer().getLocation()) && this.justTeleported) {
+                                    this.justTeleported = false;
+                                    return;
+                                }
+                            }
+                        }
+                        this.player.setLocation(d4, d5, d6, f, f1); // Copied from above
+                        // CraftBukkit end
+
                         this.B = d12 >= -0.03125D;
                         this.B &= !this.minecraftServer.getAllowFlight() && !this.player.abilities.canFly;
                         this.B &= !this.player.hasEffect(MobEffects.LEVITATION) && !this.player.cH() && !worldserver.d(this.player.getBoundingBox().g(0.0625D).b(0.0D, -0.55D, 0.0D));
@@ -365,10 +636,68 @@
     }
 
     public void a(double d0, double d1, double d2, float f, float f1) {
-        this.a(d0, d1, d2, f, f1, Collections.emptySet());
+        this.a(d0, d1, d2, f, f1, Collections.<PacketPlayOutPosition.EnumPlayerTeleportFlags>emptySet());
     }
 
     public void a(double d0, double d1, double d2, float f, float f1, Set<PacketPlayOutPosition.EnumPlayerTeleportFlags> set) {
+        // CraftBukkit start - Delegate to teleport(Location)
+        Player player = this.getPlayer();
+        Location from = player.getLocation();
+
+        double x = d0;
+        double y = d1;
+        double z = d2;
+        float yaw = f;
+        float pitch = f1;
+        if (set.contains(PacketPlayOutPosition.EnumPlayerTeleportFlags.X)) {
+            x += from.getX();
+        }
+        if (set.contains(PacketPlayOutPosition.EnumPlayerTeleportFlags.Y)) {
+            y += from.getY();
+        }
+        if (set.contains(PacketPlayOutPosition.EnumPlayerTeleportFlags.Z)) {
+            z += from.getZ();
+        }
+        if (set.contains(PacketPlayOutPosition.EnumPlayerTeleportFlags.Y_ROT)) {
+            yaw += from.getYaw();
+        }
+        if (set.contains(PacketPlayOutPosition.EnumPlayerTeleportFlags.X_ROT)) {
+            pitch += from.getPitch();
+        }
+
+
+        Location to = new Location(this.getPlayer().getWorld(), x, y, z, yaw, pitch);
+        PlayerTeleportEvent event = new PlayerTeleportEvent(player, from.clone(), to.clone(), PlayerTeleportEvent.TeleportCause.UNKNOWN);
+        this.server.getPluginManager().callEvent(event);
+
+        if (event.isCancelled() || !to.equals(event.getTo())) {
+            set.clear(); // Can't relative teleport
+            to = event.isCancelled() ? event.getFrom() : event.getTo();
+            d0 = to.getX();
+            d1 = to.getY();
+            d2 = to.getZ();
+            f = to.getYaw();
+            f1 = to.getPitch();
+        }
+
+        this.internalTeleport(d0, d1, d2, f, f1, set);
+    }
+
+    public void teleport(Location dest) {
+        internalTeleport(dest.getX(), dest.getY(), dest.getZ(), dest.getYaw(), dest.getPitch(), Collections.<PacketPlayOutPosition.EnumPlayerTeleportFlags>emptySet());
+    }
+
+    private void internalTeleport(double d0, double d1, double d2, float f, float f1, Set<PacketPlayOutPosition.EnumPlayerTeleportFlags> set) {
+        // CraftBukkit start
+        if (Float.isNaN(f)) {
+            f = 0;
+        }
+        if (Float.isNaN(f1)) {
+            f1 = 0;
+        }
+
+        this.justTeleported = true;
+        // CraftBukkit end
         double d3 = set.contains(PacketPlayOutPosition.EnumPlayerTeleportFlags.X) ? this.player.locX : 0.0D;
         double d4 = set.contains(PacketPlayOutPosition.EnumPlayerTeleportFlags.Y) ? this.player.locY : 0.0D;
         double d5 = set.contains(PacketPlayOutPosition.EnumPlayerTeleportFlags.Z) ? this.player.locZ : 0.0D;
@@ -385,6 +714,14 @@
             f3 = f1 + this.player.pitch;
         }
 
+        // CraftBukkit start - update last location
+        this.lastPosX = this.teleportPos.x;
+        this.lastPosY = this.teleportPos.y;
+        this.lastPosZ = this.teleportPos.z;
+        this.lastYaw = f2;
+        this.lastPitch = f3;
+        // CraftBukkit end
+
         if (++this.teleportAwait == Integer.MAX_VALUE) {
             this.teleportAwait = 0;
         }
@@ -396,6 +733,7 @@
 
     public void a(PacketPlayInBlockDig packetplayinblockdig) {
         PlayerConnectionUtils.ensureMainThread(packetplayinblockdig, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         WorldServer worldserver = this.minecraftServer.getWorldServer(this.player.dimension);
         BlockPosition blockposition = packetplayinblockdig.a();
 
@@ -405,7 +743,15 @@
             if (!this.player.isSpectator()) {
                 ItemStack itemstack = this.player.b(EnumHand.OFF_HAND);
 
-                this.player.a(EnumHand.OFF_HAND, this.player.b(EnumHand.MAIN_HAND));
+                // CraftBukkit start
+                PlayerSwapHandItemsEvent swapItemsEvent = new PlayerSwapHandItemsEvent(getPlayer(), CraftItemStack.asBukkitCopy(itemstack), CraftItemStack.asBukkitCopy(this.player.b(EnumHand.MAIN_HAND)));
+                this.server.getPluginManager().callEvent(swapItemsEvent);
+                if (swapItemsEvent.isCancelled()) {
+                    return;
+                }
+                itemstack = CraftItemStack.asNMSCopy(swapItemsEvent.getMainHandItem());
+                this.player.a(EnumHand.OFF_HAND, CraftItemStack.asNMSCopy(swapItemsEvent.getOffHandItem()));
+                // CraftBukkit end
                 this.player.a(EnumHand.MAIN_HAND, itemstack);
             }
 
@@ -413,6 +759,21 @@
 
         case DROP_ITEM:
             if (!this.player.isSpectator()) {
+                // limit how quickly items can be dropped
+                // If the ticks aren't the same then the count starts from 0 and we update the lastDropTick.
+                if (this.lastDropTick != MinecraftServer.currentTick) {
+                    this.dropCount = 0;
+                    this.lastDropTick = MinecraftServer.currentTick;
+                } else {
+                    // Else we increment the drop count and check the amount.
+                    this.dropCount++;
+                    if (this.dropCount >= 20) {
+                        LOGGER.warn(this.player.getName() + " dropped their items too quickly!");
+                        this.disconnect("You dropped your items too quickly (Hacking?)");
+                        return;
+                    }
+                }
+                // CraftBukkit end
                 this.player.a(false);
             }
 
@@ -446,7 +807,15 @@
                     if (!this.minecraftServer.a(worldserver, blockposition, this.player) && worldserver.getWorldBorder().a(blockposition)) {
                         this.player.playerInteractManager.a(blockposition, packetplayinblockdig.b());
                     } else {
+                        // CraftBukkit start - fire PlayerInteractEvent
+                        CraftEventFactory.callPlayerInteractEvent(this.player, Action.LEFT_CLICK_BLOCK, blockposition, packetplayinblockdig.b(), this.player.inventory.getItemInHand(), EnumHand.MAIN_HAND);
                         this.player.playerConnection.sendPacket(new PacketPlayOutBlockChange(worldserver, blockposition));
+                        // Update any tile entity data for this block
+                        TileEntity tileentity = worldserver.getTileEntity(blockposition);
+                        if (tileentity != null) {
+                            this.player.playerConnection.sendPacket(tileentity.getUpdatePacket());
+                        }
+                        // CraftBukkit end
                     }
                 } else {
                     if (packetplayinblockdig.c() == PacketPlayInBlockDig.EnumPlayerDigType.STOP_DESTROY_BLOCK) {
@@ -466,10 +835,12 @@
         default:
             throw new IllegalArgumentException("Invalid player action");
         }
+        // CraftBukkit end
     }
 
     public void a(PacketPlayInUseItem packetplayinuseitem) {
         PlayerConnectionUtils.ensureMainThread(packetplayinuseitem, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         WorldServer worldserver = this.minecraftServer.getWorldServer(this.player.dimension);
         EnumHand enumhand = packetplayinuseitem.c();
         ItemStack itemstack = this.player.b(enumhand);
@@ -483,6 +854,13 @@
             chatmessage.getChatModifier().setColor(EnumChatFormat.RED);
             this.player.playerConnection.sendPacket(new PacketPlayOutChat(chatmessage, (byte) 2));
         } else if (this.teleportPos == null && this.player.d((double) blockposition.getX() + 0.5D, (double) blockposition.getY() + 0.5D, (double) blockposition.getZ() + 0.5D) < 64.0D && !this.minecraftServer.a(worldserver, blockposition, this.player) && worldserver.getWorldBorder().a(blockposition)) {
+            // CraftBukkit start - Check if we can actually do something over this large a distance
+            Location eyeLoc = this.getPlayer().getEyeLocation();
+            double reachDistance = NumberConversions.square(eyeLoc.getX() - blockposition.getX()) + NumberConversions.square(eyeLoc.getY() - blockposition.getY()) + NumberConversions.square(eyeLoc.getZ() - blockposition.getZ());
+            if (reachDistance > (this.getPlayer().getGameMode() == org.bukkit.GameMode.CREATIVE ? CREATIVE_PLACE_DISTANCE_SQUARED : SURVIVAL_PLACE_DISTANCE_SQUARED)) {
+                return;
+            }
+            // CraftBukkit end
             this.player.playerInteractManager.a(this.player, worldserver, itemstack, enumhand, blockposition, enumdirection, packetplayinuseitem.d(), packetplayinuseitem.e(), packetplayinuseitem.f());
         }
 
@@ -492,13 +870,52 @@
 
     public void a(PacketPlayInBlockPlace packetplayinblockplace) {
         PlayerConnectionUtils.ensureMainThread(packetplayinblockplace, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         WorldServer worldserver = this.minecraftServer.getWorldServer(this.player.dimension);
         EnumHand enumhand = packetplayinblockplace.a();
         ItemStack itemstack = this.player.b(enumhand);
 
         this.player.resetIdleTimer();
         if (!itemstack.isEmpty()) {
-            this.player.playerInteractManager.a(this.player, worldserver, itemstack, enumhand);
+            // CraftBukkit start
+            // Raytrace to look for 'rogue armswings'
+            float f1 = this.player.pitch;
+            float f2 = this.player.yaw;
+            double d0 = this.player.locX;
+            double d1 = this.player.locY + (double) this.player.getHeadHeight();
+            double d2 = this.player.locZ;
+            Vec3D vec3d = new Vec3D(d0, d1, d2);
+
+            float f3 = MathHelper.cos(-f2 * 0.017453292F - 3.1415927F);
+            float f4 = MathHelper.sin(-f2 * 0.017453292F - 3.1415927F);
+            float f5 = -MathHelper.cos(-f1 * 0.017453292F);
+            float f6 = MathHelper.sin(-f1 * 0.017453292F);
+            float f7 = f4 * f5;
+            float f8 = f3 * f5;
+            double d3 = player.playerInteractManager.getGameMode()== EnumGamemode.CREATIVE ? 5.0D : 4.5D;
+            Vec3D vec3d1 = vec3d.add((double) f7 * d3, (double) f6 * d3, (double) f8 * d3);
+            MovingObjectPosition movingobjectposition = this.player.world.rayTrace(vec3d, vec3d1, false);
+
+            boolean cancelled;
+            if (movingobjectposition == null || movingobjectposition.type != MovingObjectPosition.EnumMovingObjectType.BLOCK) {
+                org.bukkit.event.player.PlayerInteractEvent event = CraftEventFactory.callPlayerInteractEvent(this.player, Action.RIGHT_CLICK_AIR, itemstack, enumhand);
+                cancelled = event.useItemInHand() == Event.Result.DENY;
+            } else {
+                if (player.playerInteractManager.firedInteract) {
+                    player.playerInteractManager.firedInteract = false;
+                    cancelled = player.playerInteractManager.interactResult;
+                } else {
+                    org.bukkit.event.player.PlayerInteractEvent event = CraftEventFactory.callPlayerInteractEvent(player, Action.RIGHT_CLICK_BLOCK, movingobjectposition.a(), movingobjectposition.direction, itemstack, true, enumhand);
+                    cancelled = event.useItemInHand() == Event.Result.DENY;
+                }
+            }
+
+            if (cancelled) {
+                this.player.getBukkitEntity().updateInventory(); // SPIGOT-2524
+            } else {
+                this.player.playerInteractManager.a(this.player, worldserver, itemstack, enumhand);
+            }
+            // CraftBukkit end
         }
     }
 
@@ -509,8 +926,8 @@
             WorldServer[] aworldserver = this.minecraftServer.worldServer;
             int i = aworldserver.length;
 
-            for (int j = 0; j < i; ++j) {
-                WorldServer worldserver = aworldserver[j];
+            // CraftBukkit - use the worlds array list
+            for (WorldServer worldserver : minecraftServer.worlds) {
 
                 if (worldserver != null) {
                     entity = packetplayinspectate.a(worldserver);
@@ -523,6 +940,8 @@
             if (entity != null) {
                 this.player.setSpectatorTarget(this.player);
                 this.player.stopRiding();
+
+                /* CraftBukkit start - replace with bukkit handling for multi-world
                 if (entity.world == this.player.world) {
                     this.player.enderTeleportTo(entity.locX, entity.locY, entity.locZ);
                 } else {
@@ -548,12 +967,19 @@
                     this.minecraftServer.getPlayerList().b(this.player, worldserver2);
                     this.minecraftServer.getPlayerList().updateClient(this.player);
                 }
+                */
+                this.player.getBukkitEntity().teleport(entity.getBukkitEntity(), PlayerTeleportEvent.TeleportCause.SPECTATE);
+                // CraftBukkit end
             }
         }
 
     }
 
-    public void a(PacketPlayInResourcePackStatus packetplayinresourcepackstatus) {}
+    // CraftBukkit start
+    public void a(PacketPlayInResourcePackStatus packetplayinresourcepackstatus) {
+        this.server.getPluginManager().callEvent(new PlayerResourcePackStatusEvent(getPlayer(), PlayerResourcePackStatusEvent.Status.values()[packetplayinresourcepackstatus.status.ordinal()]));
+    }
+    // CraftBukkit end
 
     public void a(PacketPlayInBoatMove packetplayinboatmove) {
         PlayerConnectionUtils.ensureMainThread(packetplayinboatmove, this, this.player.x());
@@ -566,14 +992,29 @@
     }
 
     public void a(IChatBaseComponent ichatbasecomponent) {
-        PlayerConnection.LOGGER.info("{} lost connection: {}", new Object[] { this.player.getName(), ichatbasecomponent});
+        // CraftBukkit start - Rarely it would send a disconnect line twice
+        if (this.processedDisconnect) {
+            return;
+        } else {
+            this.processedDisconnect = true;
+        }
+        // CraftBukkit end
+        PlayerConnection.LOGGER.info("{} lost connection: {}", new Object[] { this.player.getName(), ichatbasecomponent.toPlainText()});// CraftBukkit - Don't toString().
+        // CraftBukkit start - Replace vanilla quit message handling with our own.
+        /*
         this.minecraftServer.aD();
         ChatMessage chatmessage = new ChatMessage("multiplayer.player.left", new Object[] { this.player.getScoreboardDisplayName()});
 
         chatmessage.getChatModifier().setColor(EnumChatFormat.YELLOW);
         this.minecraftServer.getPlayerList().sendMessage(chatmessage);
+        */
+
         this.player.t();
-        this.minecraftServer.getPlayerList().disconnect(this.player);
+        String quitMessage = this.minecraftServer.getPlayerList().disconnect(this.player);
+        if ((quitMessage != null) && (quitMessage.length() > 0)) {
+            this.minecraftServer.getPlayerList().sendMessage(CraftChatMessage.fromString(quitMessage));
+        }
+        // CraftBukkit end
         if (this.minecraftServer.R() && this.player.getName().equals(this.minecraftServer.Q())) {
             PlayerConnection.LOGGER.info("Stopping singleplayer server as player logged out");
             this.minecraftServer.safeShutdown();
@@ -595,6 +1036,15 @@
             }
         }
 
+        // CraftBukkit start
+        if (packet == null) {
+            return;
+        } else if (packet instanceof PacketPlayOutSpawnPosition) {
+            PacketPlayOutSpawnPosition packet6 = (PacketPlayOutSpawnPosition) packet;
+            this.player.compassTarget = new Location(this.getPlayer().getWorld(), packet6.position.getX(), packet6.position.getY(), packet6.position.getZ());
+        }
+        // CraftBukkit end
+
         try {
             this.networkManager.sendPacket(packet);
         } catch (Throwable throwable) {
@@ -616,17 +1066,32 @@
 
     public void a(PacketPlayInHeldItemSlot packetplayinhelditemslot) {
         PlayerConnectionUtils.ensureMainThread(packetplayinhelditemslot, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         if (packetplayinhelditemslot.a() >= 0 && packetplayinhelditemslot.a() < PlayerInventory.getHotbarSize()) {
+            PlayerItemHeldEvent event = new PlayerItemHeldEvent(this.getPlayer(), this.player.inventory.itemInHandIndex, packetplayinhelditemslot.a());
+            this.server.getPluginManager().callEvent(event);
+            if (event.isCancelled()) {
+                this.sendPacket(new PacketPlayOutHeldItemSlot(this.player.inventory.itemInHandIndex));
+                this.player.resetIdleTimer();
+                return;
+            }
+            // CraftBukkit end
             this.player.inventory.itemInHandIndex = packetplayinhelditemslot.a();
             this.player.resetIdleTimer();
         } else {
             PlayerConnection.LOGGER.warn("{} tried to set an invalid carried item", new Object[] { this.player.getName()});
+            this.disconnect("Nope!"); // CraftBukkit
         }
     }
 
     public void a(PacketPlayInChat packetplayinchat) {
-        PlayerConnectionUtils.ensureMainThread(packetplayinchat, this, this.player.x());
-        if (this.player.getChatFlags() == EntityHuman.EnumChatVisibility.HIDDEN) {
+        // CraftBukkit start - async chat
+        boolean isSync = packetplayinchat.a().startsWith("/");
+        if (packetplayinchat.a().startsWith("/")) {
+            PlayerConnectionUtils.ensureMainThread(packetplayinchat, this, this.player.x());
+        }
+        // CraftBukkit end
+        if (this.player.dead || this.player.getChatFlags() == EntityHuman.EnumChatVisibility.HIDDEN) { // CraftBukkit - dead men tell no tales
             ChatMessage chatmessage = new ChatMessage("chat.cannotSend", new Object[0]);
 
             chatmessage.getChatModifier().setColor(EnumChatFormat.RED);
@@ -639,39 +1104,249 @@
 
             for (int i = 0; i < s.length(); ++i) {
                 if (!SharedConstants.isAllowedChatCharacter(s.charAt(i))) {
-                    this.disconnect("Illegal characters in chat");
+                    // CraftBukkit start - threadsafety
+                    if (!isSync) {
+                        Waitable waitable = new Waitable() {
+                            @Override
+                            protected Object evaluate() {
+                                PlayerConnection.this.disconnect("Illegal characters in chat");
+                                return null;
+                            }
+                        };
+
+                        this.minecraftServer.processQueue.add(waitable);
+
+                        try {
+                            waitable.get();
+                        } catch (InterruptedException e) {
+                            Thread.currentThread().interrupt();
+                        } catch (ExecutionException e) {
+                            throw new RuntimeException(e);
+                        }
+                    } else {
+                        this.disconnect("Illegal characters in chat");
+                    }
+                    // CraftBukkit end
                     return;
                 }
             }
 
-            if (s.startsWith("/")) {
-                this.handleCommand(s);
+            // CraftBukkit start
+            if (isSync) {
+                try {
+                    this.minecraftServer.server.playerCommandState = true;
+                    this.handleCommand(s);
+                } finally {
+                    this.minecraftServer.server.playerCommandState = false;
+                }
+            } else if (s.isEmpty()) {
+                LOGGER.warn(this.player.getName() + " tried to send an empty message");
+            } else if (getPlayer().isConversing()) {
+                getPlayer().acceptConversationInput(s);
+            } else if (this.player.getChatFlags() == EntityHuman.EnumChatVisibility.SYSTEM) { // Re-add "Command Only" flag check
+                ChatMessage chatmessage = new ChatMessage("chat.cannotSend", new Object[0]);
+
+                chatmessage.getChatModifier().setColor(EnumChatFormat.RED);
+                this.sendPacket(new PacketPlayOutChat(chatmessage));
+            } else if (true) {
+                this.chat(s, true);
+                // CraftBukkit end - the below is for reference. :)
             } else {
                 ChatMessage chatmessage1 = new ChatMessage("chat.type.text", new Object[] { this.player.getScoreboardDisplayName(), s});
 
                 this.minecraftServer.getPlayerList().sendMessage(chatmessage1, false);
             }
 
-            this.chatThrottle += 20;
-            if (this.chatThrottle > 200 && !this.minecraftServer.getPlayerList().isOp(this.player.getProfile())) {
-                this.disconnect("disconnect.spam");
+            // CraftBukkit start - replaced with thread safe throttle
+            // this.chatThrottle += 20;
+            if (chatSpamField.addAndGet(this, 20) > 200 && !this.minecraftServer.getPlayerList().isOp(this.player.getProfile())) {
+                if (!isSync) {
+                    Waitable waitable = new Waitable() {
+                        @Override
+                        protected Object evaluate() {
+                            PlayerConnection.this.disconnect("disconnect.spam");
+                            return null;
+                        }
+                    };
+
+                    this.minecraftServer.processQueue.add(waitable);
+
+                    try {
+                        waitable.get();
+                    } catch (InterruptedException e) {
+                        Thread.currentThread().interrupt();
+                    } catch (ExecutionException e) {
+                        throw new RuntimeException(e);
+                    }
+                } else {
+                    this.disconnect("disconnect.spam");
+                }
+                // CraftBukkit end
             }
 
         }
     }
 
-    private void handleCommand(String s) {
-        this.minecraftServer.getCommandHandler().a(this.player, s);
+    // CraftBukkit start - add method
+    public void chat(String s, boolean async) {
+        if (s.isEmpty() || this.player.getChatFlags() == EntityHuman.EnumChatVisibility.HIDDEN) {
+            return;
+        }
+
+        if (!async && s.startsWith("/")) {
+            this.handleCommand(s);
+        } else if (this.player.getChatFlags() == EntityHuman.EnumChatVisibility.SYSTEM) {
+            // Do nothing, this is coming from a plugin
+        } else {
+            Player player = this.getPlayer();
+            AsyncPlayerChatEvent event = new AsyncPlayerChatEvent(async, player, s, new LazyPlayerSet(minecraftServer));
+            this.server.getPluginManager().callEvent(event);
+
+            if (PlayerChatEvent.getHandlerList().getRegisteredListeners().length != 0) {
+                // Evil plugins still listening to deprecated event
+                final PlayerChatEvent queueEvent = new PlayerChatEvent(player, event.getMessage(), event.getFormat(), event.getRecipients());
+                queueEvent.setCancelled(event.isCancelled());
+                Waitable waitable = new Waitable() {
+                    @Override
+                    protected Object evaluate() {
+                        org.bukkit.Bukkit.getPluginManager().callEvent(queueEvent);
+
+                        if (queueEvent.isCancelled()) {
+                            return null;
+                        }
+
+                        String message = String.format(queueEvent.getFormat(), queueEvent.getPlayer().getDisplayName(), queueEvent.getMessage());
+                        PlayerConnection.this.minecraftServer.console.sendMessage(message);
+                        if (((LazyPlayerSet) queueEvent.getRecipients()).isLazy()) {
+                            for (Object player : PlayerConnection.this.minecraftServer.getPlayerList().players) {
+                                ((EntityPlayer) player).sendMessage(CraftChatMessage.fromString(message));
+                            }
+                        } else {
+                            for (Player player : queueEvent.getRecipients()) {
+                                player.sendMessage(message);
+                            }
+                        }
+                        return null;
+                    }};
+                if (async) {
+                    minecraftServer.processQueue.add(waitable);
+                } else {
+                    waitable.run();
+                }
+                try {
+                    waitable.get();
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt(); // This is proper habit for java. If we aren't handling it, pass it on!
+                } catch (ExecutionException e) {
+                    throw new RuntimeException("Exception processing chat event", e.getCause());
+                }
+            } else {
+                if (event.isCancelled()) {
+                    return;
+                }
+
+                s = String.format(event.getFormat(), event.getPlayer().getDisplayName(), event.getMessage());
+                minecraftServer.console.sendMessage(s);
+                if (((LazyPlayerSet) event.getRecipients()).isLazy()) {
+                    for (Object recipient : minecraftServer.getPlayerList().players) {
+                        ((EntityPlayer) recipient).sendMessage(CraftChatMessage.fromString(s));
+                    }
+                } else {
+                    for (Player recipient : event.getRecipients()) {
+                        recipient.sendMessage(s);
+                    }
+                }
+            }
+        }
+    }
+    // CraftBukkit end
+
+   private void handleCommand(String s) {
+       // CraftBukkit start - whole method
+        this.LOGGER.info(this.player.getName() + " issued server command: " + s);
+
+        CraftPlayer player = this.getPlayer();
+
+        PlayerCommandPreprocessEvent event = new PlayerCommandPreprocessEvent(player, s, new LazyPlayerSet(minecraftServer));
+        this.server.getPluginManager().callEvent(event);
+
+        if (event.isCancelled()) {
+            return;
+        }
+
+        try {
+            if (this.server.dispatchCommand(event.getPlayer(), event.getMessage().substring(1))) {
+                return;
+            }
+        } catch (org.bukkit.command.CommandException ex) {
+            player.sendMessage(org.bukkit.ChatColor.RED + "An internal error occurred while attempting to perform this command");
+            java.util.logging.Logger.getLogger(PlayerConnection.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
+            return;
+        }
+        // this.minecraftServer.getCommandHandler().a(this.player, s);
+        // CraftBukkit end
     }
 
     public void a(PacketPlayInArmAnimation packetplayinarmanimation) {
         PlayerConnectionUtils.ensureMainThread(packetplayinarmanimation, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         this.player.resetIdleTimer();
+        // CraftBukkit start - Raytrace to look for 'rogue armswings'
+        float f1 = this.player.pitch;
+        float f2 = this.player.yaw;
+        double d0 = this.player.locX;
+        double d1 = this.player.locY + (double) this.player.getHeadHeight();
+        double d2 = this.player.locZ;
+        Vec3D vec3d = new Vec3D(d0, d1, d2);
+
+        float f3 = MathHelper.cos(-f2 * 0.017453292F - 3.1415927F);
+        float f4 = MathHelper.sin(-f2 * 0.017453292F - 3.1415927F);
+        float f5 = -MathHelper.cos(-f1 * 0.017453292F);
+        float f6 = MathHelper.sin(-f1 * 0.017453292F);
+        float f7 = f4 * f5;
+        float f8 = f3 * f5;
+        double d3 = player.playerInteractManager.getGameMode()== EnumGamemode.CREATIVE ? 5.0D : 4.5D;
+        Vec3D vec3d1 = vec3d.add((double) f7 * d3, (double) f6 * d3, (double) f8 * d3);
+        MovingObjectPosition movingobjectposition = this.player.world.rayTrace(vec3d, vec3d1, false);
+
+        if (movingobjectposition == null || movingobjectposition.type != MovingObjectPosition.EnumMovingObjectType.BLOCK) {
+            CraftEventFactory.callPlayerInteractEvent(this.player, Action.LEFT_CLICK_AIR, this.player.inventory.getItemInHand(), EnumHand.MAIN_HAND);
+        }
+
+        // Arm swing animation
+        PlayerAnimationEvent event = new PlayerAnimationEvent(this.getPlayer());
+        this.server.getPluginManager().callEvent(event);
+
+        if (event.isCancelled()) return;
+        // CraftBukkit end
         this.player.a(packetplayinarmanimation.a());
     }
 
     public void a(PacketPlayInEntityAction packetplayinentityaction) {
         PlayerConnectionUtils.ensureMainThread(packetplayinentityaction, this, this.player.x());
+        // CraftBukkit start
+        if (this.player.dead) return;
+        switch (packetplayinentityaction.b()) {
+            case START_SNEAKING:
+            case STOP_SNEAKING:
+                PlayerToggleSneakEvent event = new PlayerToggleSneakEvent(this.getPlayer(), packetplayinentityaction.b() == PacketPlayInEntityAction.EnumPlayerAction.START_SNEAKING);
+                this.server.getPluginManager().callEvent(event);
+
+                if (event.isCancelled()) {
+                    return;
+                }
+                break;
+            case START_SPRINTING:
+            case STOP_SPRINTING:
+                PlayerToggleSprintEvent e2 = new PlayerToggleSprintEvent(this.getPlayer(), packetplayinentityaction.b() == PacketPlayInEntityAction.EnumPlayerAction.START_SPRINTING);
+                this.server.getPluginManager().callEvent(e2);
+
+                if (e2.isCancelled()) {
+                    return;
+                }
+                break;
+        }
+        // CraftBukkit end
         this.player.resetIdleTimer();
         IJumpable ijumpable;
 
@@ -743,6 +1418,7 @@
 
     public void a(PacketPlayInUseEntity packetplayinuseentity) {
         PlayerConnectionUtils.ensureMainThread(packetplayinuseentity, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         WorldServer worldserver = this.minecraftServer.getWorldServer(this.player.dimension);
         Entity entity = packetplayinuseentity.a((World) worldserver);
 
@@ -758,20 +1434,68 @@
             if (this.player.h(entity) < d0) {
                 EnumHand enumhand;
 
+                ItemStack itemInHand = this.player.b(packetplayinuseentity.b() == null ? EnumHand.MAIN_HAND : packetplayinuseentity.b()); // CraftBukkit
+
+                if (packetplayinuseentity.a() == PacketPlayInUseEntity.EnumEntityUseAction.INTERACT
+                        || packetplayinuseentity.a() == PacketPlayInUseEntity.EnumEntityUseAction.INTERACT_AT) {
+                    // CraftBukkit start
+                    boolean triggerLeashUpdate = itemInHand != null && itemInHand.getItem() == Items.LEAD && entity instanceof EntityInsentient;
+                    Item origItem = this.player.inventory.getItemInHand() == null ? null : this.player.inventory.getItemInHand().getItem();
+                    PlayerInteractEntityEvent event;
+                    if (packetplayinuseentity.a() == PacketPlayInUseEntity.EnumEntityUseAction.INTERACT) {
+                        event = new PlayerInteractEntityEvent((Player) this.getPlayer(), entity.getBukkitEntity(), (packetplayinuseentity.b() == EnumHand.OFF_HAND) ? EquipmentSlot.OFF_HAND : EquipmentSlot.HAND);
+                    } else {
+                        Vec3D target = packetplayinuseentity.c();
+                        event = new PlayerInteractAtEntityEvent((Player) this.getPlayer(), entity.getBukkitEntity(), new org.bukkit.util.Vector(target.x, target.y, target.z), (packetplayinuseentity.b() == EnumHand.OFF_HAND) ? EquipmentSlot.OFF_HAND : EquipmentSlot.HAND);
+                    }
+                    this.server.getPluginManager().callEvent(event);
+
+                    if (triggerLeashUpdate && (event.isCancelled() || this.player.inventory.getItemInHand() == null || this.player.inventory.getItemInHand().getItem() != Items.LEAD)) {
+                        // Refresh the current leash state
+                        this.sendPacket(new PacketPlayOutAttachEntity(entity, ((EntityInsentient) entity).getLeashHolder()));
+                    }
+
+                    if (event.isCancelled() || this.player.inventory.getItemInHand() == null || this.player.inventory.getItemInHand().getItem() != origItem) {
+                        // Refresh the current entity metadata
+                        this.sendPacket(new PacketPlayOutEntityMetadata(entity.getId(), entity.datawatcher, true));
+                    }
+
+                    if (event.isCancelled()) {
+                        return;
+                    }
+                    // CraftBukkit end
+                }
+
                 if (packetplayinuseentity.a() == PacketPlayInUseEntity.EnumEntityUseAction.INTERACT) {
                     enumhand = packetplayinuseentity.b();
                     this.player.a(entity, enumhand);
+                    // CraftBukkit start
+                    if (!itemInHand.isEmpty() && itemInHand.getCount() <= -1) {
+                        this.player.updateInventory(this.player.activeContainer);
+                    }
+                    // CraftBukkit end
                 } else if (packetplayinuseentity.a() == PacketPlayInUseEntity.EnumEntityUseAction.INTERACT_AT) {
                     enumhand = packetplayinuseentity.b();
                     entity.a(this.player, packetplayinuseentity.c(), enumhand);
+                    // CraftBukkit start
+                    if (!itemInHand.isEmpty() && itemInHand.getCount() <= -1) {
+                        this.player.updateInventory(this.player.activeContainer);
+                    }
+                    // CraftBukkit end
                 } else if (packetplayinuseentity.a() == PacketPlayInUseEntity.EnumEntityUseAction.ATTACK) {
-                    if (entity instanceof EntityItem || entity instanceof EntityExperienceOrb || entity instanceof EntityArrow || entity == this.player) {
+                    if (entity instanceof EntityItem || entity instanceof EntityExperienceOrb || entity instanceof EntityArrow || (entity == this.player && !player.isSpectator())) { // CraftBukkit
                         this.disconnect("Attempting to attack an invalid entity");
                         this.minecraftServer.warning("Player " + this.player.getName() + " tried to attack an invalid entity");
                         return;
                     }
 
                     this.player.attack(entity);
+
+                    // CraftBukkit start
+                    if (!itemInHand.isEmpty() && itemInHand.getCount() <= -1) {
+                        this.player.updateInventory(this.player.activeContainer);
+                    }
+                    // CraftBukkit end
                 }
             }
         }
@@ -787,7 +1511,8 @@
         case PERFORM_RESPAWN:
             if (this.player.viewingCredits) {
                 this.player.viewingCredits = false;
-                this.player = this.minecraftServer.getPlayerList().moveToWorld(this.player, 0, true);
+                // this.player = this.minecraftServer.getPlayerList().moveToWorld(this.player, 0, true);
+                this.minecraftServer.getPlayerList().changeDimension(this.player, 0, PlayerTeleportEvent.TeleportCause.END_PORTAL); // CraftBukkit - reroute logic through custom portal management
             } else {
                 if (this.player.getHealth() > 0.0F) {
                     return;
@@ -813,14 +1538,20 @@
 
     public void a(PacketPlayInCloseWindow packetplayinclosewindow) {
         PlayerConnectionUtils.ensureMainThread(packetplayinclosewindow, this, this.player.x());
+
+        if (this.player.isFrozen()) return; // CraftBukkit
+        CraftEventFactory.handleInventoryCloseEvent(this.player); // CraftBukkit
+
         this.player.s();
     }
 
     public void a(PacketPlayInWindowClick packetplayinwindowclick) {
         PlayerConnectionUtils.ensureMainThread(packetplayinwindowclick, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         this.player.resetIdleTimer();
         if (this.player.activeContainer.windowId == packetplayinwindowclick.a() && this.player.activeContainer.c(this.player)) {
-            if (this.player.isSpectator()) {
+            boolean cancelled = this.player.isSpectator(); // CraftBukkit - see below if
+            if (false/*this.player.isSpectator()*/) { // CraftBukkit
                 NonNullList nonnulllist = NonNullList.a();
 
                 for (int i = 0; i < this.player.activeContainer.c.size(); ++i) {
@@ -829,8 +1560,279 @@
 
                 this.player.a(this.player.activeContainer, nonnulllist);
             } else {
-                ItemStack itemstack = this.player.activeContainer.a(packetplayinwindowclick.b(), packetplayinwindowclick.c(), packetplayinwindowclick.f(), this.player);
+                // CraftBukkit start - Call InventoryClickEvent
+                if (packetplayinwindowclick.b() < -1 && packetplayinwindowclick.b() != -999) {
+                    return;
+                }
 
+                InventoryView inventory = this.player.activeContainer.getBukkitView();
+                SlotType type = CraftInventoryView.getSlotType(inventory, packetplayinwindowclick.b());
+
+                InventoryClickEvent event;
+                ClickType click = ClickType.UNKNOWN;
+                InventoryAction action = InventoryAction.UNKNOWN;
+
+                ItemStack itemstack = ItemStack.a;
+
+                switch (packetplayinwindowclick.f()) {
+                    case PICKUP:
+                        if (packetplayinwindowclick.c() == 0) {
+                            click = ClickType.LEFT;
+                        } else if (packetplayinwindowclick.c() == 1) {
+                            click = ClickType.RIGHT;
+                        }
+                        if (packetplayinwindowclick.c() == 0 || packetplayinwindowclick.c() == 1) {
+                            action = InventoryAction.NOTHING; // Don't want to repeat ourselves
+                            if (packetplayinwindowclick.b() == -999) {
+                                if (!player.inventory.getCarried().isEmpty()) {
+                                    action = packetplayinwindowclick.c() == 0 ? InventoryAction.DROP_ALL_CURSOR : InventoryAction.DROP_ONE_CURSOR;
+                                }
+                            } else if (packetplayinwindowclick.b() < 0)  {
+                                action = InventoryAction.NOTHING;
+                            } else {
+                                Slot slot = this.player.activeContainer.getSlot(packetplayinwindowclick.b());
+                                if (slot != null) {
+                                    ItemStack clickedItem = slot.getItem();
+                                    ItemStack cursor = player.inventory.getCarried();
+                                    if (clickedItem.isEmpty()) {
+                                        if (!cursor.isEmpty()) {
+                                            action = packetplayinwindowclick.c() == 0 ? InventoryAction.PLACE_ALL : InventoryAction.PLACE_ONE;
+                                        }
+                                    } else if (slot.isAllowed(player)) {
+                                        if (cursor.isEmpty()) {
+                                            action = packetplayinwindowclick.c() == 0 ? InventoryAction.PICKUP_ALL : InventoryAction.PICKUP_HALF;
+                                        } else if (slot.isAllowed(cursor)) {
+                                            if (clickedItem.doMaterialsMatch(cursor) && ItemStack.equals(clickedItem, cursor)) {
+                                                int toPlace = packetplayinwindowclick.c() == 0 ? cursor.getCount() : 1;
+                                                toPlace = Math.min(toPlace, clickedItem.getMaxStackSize() - clickedItem.getCount());
+                                                toPlace = Math.min(toPlace, slot.inventory.getMaxStackSize() - clickedItem.getCount());
+                                                if (toPlace == 1) {
+                                                    action = InventoryAction.PLACE_ONE;
+                                                } else if (toPlace == cursor.getCount()) {
+                                                    action = InventoryAction.PLACE_ALL;
+                                                } else if (toPlace < 0) {
+                                                    action = toPlace != -1 ? InventoryAction.PICKUP_SOME : InventoryAction.PICKUP_ONE; // this happens with oversized stacks
+                                                } else if (toPlace != 0) {
+                                                    action = InventoryAction.PLACE_SOME;
+                                                }
+                                            } else if (cursor.getCount() <= slot.getMaxStackSize()) {
+                                                action = InventoryAction.SWAP_WITH_CURSOR;
+                                            }
+                                        } else if (cursor.getItem() == clickedItem.getItem() && (!cursor.usesData() || cursor.getData() == clickedItem.getData()) && ItemStack.equals(cursor, clickedItem)) {
+                                            if (clickedItem.getCount() >= 0) {
+                                                if (clickedItem.getCount() + cursor.getCount() <= cursor.getMaxStackSize()) {
+                                                    // As of 1.5, this is result slots only
+                                                    action = InventoryAction.PICKUP_ALL;
+                                                }
+                                            }
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                        break;
+                    // TODO check on updates
+                    case QUICK_MOVE:
+                        if (packetplayinwindowclick.c() == 0) {
+                            click = ClickType.SHIFT_LEFT;
+                        } else if (packetplayinwindowclick.c() == 1) {
+                            click = ClickType.SHIFT_RIGHT;
+                        }
+                        if (packetplayinwindowclick.c() == 0 || packetplayinwindowclick.c() == 1) {
+                            if (packetplayinwindowclick.b() < 0) {
+                                action = InventoryAction.NOTHING;
+                            } else {
+                                Slot slot = this.player.activeContainer.getSlot(packetplayinwindowclick.b());
+                                if (slot != null && slot.isAllowed(this.player) && slot.hasItem()) {
+                                    action = InventoryAction.MOVE_TO_OTHER_INVENTORY;
+                                } else {
+                                    action = InventoryAction.NOTHING;
+                                }
+                            }
+                        }
+                        break;
+                    case SWAP:
+                        if (packetplayinwindowclick.c() >= 0 && packetplayinwindowclick.c() < 9) {
+                            click = ClickType.NUMBER_KEY;
+                            Slot clickedSlot = this.player.activeContainer.getSlot(packetplayinwindowclick.b());
+                            if (clickedSlot.isAllowed(player)) {
+                                ItemStack hotbar = this.player.inventory.getItem(packetplayinwindowclick.c());
+                                boolean canCleanSwap = hotbar.isEmpty() || (clickedSlot.inventory == player.inventory && clickedSlot.isAllowed(hotbar)); // the slot will accept the hotbar item
+                                if (clickedSlot.hasItem()) {
+                                    if (canCleanSwap) {
+                                        action = InventoryAction.HOTBAR_SWAP;
+                                    } else {
+                                        int firstEmptySlot = player.inventory.getFirstEmptySlotIndex();
+                                        if (firstEmptySlot > -1) {
+                                            action = InventoryAction.HOTBAR_MOVE_AND_READD;
+                                        } else {
+                                            action = InventoryAction.NOTHING; // This is not sane! Mojang: You should test for other slots of same type
+                                        }
+                                    }
+                                } else if (!clickedSlot.hasItem() && !hotbar.isEmpty() && clickedSlot.isAllowed(hotbar)) {
+                                    action = InventoryAction.HOTBAR_SWAP;
+                                } else {
+                                    action = InventoryAction.NOTHING;
+                                }
+                            } else {
+                                action = InventoryAction.NOTHING;
+                            }
+                        }
+                        break;
+                    case CLONE:
+                        if (packetplayinwindowclick.c() == 2) {
+                            click = ClickType.MIDDLE;
+                            if (packetplayinwindowclick.b() == -999) {
+                                action = InventoryAction.NOTHING;
+                            } else {
+                                Slot slot = this.player.activeContainer.getSlot(packetplayinwindowclick.b());
+                                if (slot != null && slot.hasItem() && player.abilities.canInstantlyBuild && player.inventory.getCarried().isEmpty()) {
+                                    action = InventoryAction.CLONE_STACK;
+                                } else {
+                                    action = InventoryAction.NOTHING;
+                                }
+                            }
+                        } else {
+                            click = ClickType.UNKNOWN;
+                            action = InventoryAction.UNKNOWN;
+                        }
+                        break;
+                    case THROW:
+                        if (packetplayinwindowclick.b() >= 0) {
+                            if (packetplayinwindowclick.c() == 0) {
+                                click = ClickType.DROP;
+                                Slot slot = this.player.activeContainer.getSlot(packetplayinwindowclick.b());
+                                if (slot != null && slot.hasItem() && slot.isAllowed(player) && !slot.getItem().isEmpty() && slot.getItem().getItem() != Item.getItemOf(Blocks.AIR)) {
+                                    action = InventoryAction.DROP_ONE_SLOT;
+                                } else {
+                                    action = InventoryAction.NOTHING;
+                                }
+                            } else if (packetplayinwindowclick.c() == 1) {
+                                click = ClickType.CONTROL_DROP;
+                                Slot slot = this.player.activeContainer.getSlot(packetplayinwindowclick.b());
+                                if (slot != null && slot.hasItem() && slot.isAllowed(player) && !slot.getItem().isEmpty() && slot.getItem().getItem() != Item.getItemOf(Blocks.AIR)) {
+                                    action = InventoryAction.DROP_ALL_SLOT;
+                                } else {
+                                    action = InventoryAction.NOTHING;
+                                }
+                            }
+                        } else {
+                            // Sane default (because this happens when they are holding nothing. Don't ask why.)
+                            click = ClickType.LEFT;
+                            if (packetplayinwindowclick.c() == 1) {
+                                click = ClickType.RIGHT;
+                            }
+                            action = InventoryAction.NOTHING;
+                        }
+                        break;
+                    case QUICK_CRAFT:
+                        itemstack = this.player.activeContainer.a(packetplayinwindowclick.b(), packetplayinwindowclick.c(), packetplayinwindowclick.f(), this.player);
+                        break;
+                    case PICKUP_ALL:
+                        click = ClickType.DOUBLE_CLICK;
+                        action = InventoryAction.NOTHING;
+                        if (packetplayinwindowclick.b() >= 0 && !this.player.inventory.getCarried().isEmpty()) {
+                            ItemStack cursor = this.player.inventory.getCarried();
+                            action = InventoryAction.NOTHING;
+                            // Quick check for if we have any of the item
+                            if (inventory.getTopInventory().contains(org.bukkit.Material.getMaterial(Item.getId(cursor.getItem()))) || inventory.getBottomInventory().contains(org.bukkit.Material.getMaterial(Item.getId(cursor.getItem())))) {
+                                action = InventoryAction.COLLECT_TO_CURSOR;
+                            }
+                        }
+                        break;
+                    default:
+                        break;
+                }
+
+                if (packetplayinwindowclick.f() != InventoryClickType.QUICK_CRAFT) {
+                    if (click == ClickType.NUMBER_KEY) {
+                        event = new InventoryClickEvent(inventory, type, packetplayinwindowclick.b(), click, action, packetplayinwindowclick.c());
+                    } else {
+                        event = new InventoryClickEvent(inventory, type, packetplayinwindowclick.b(), click, action);
+                    }
+
+                    org.bukkit.inventory.Inventory top = inventory.getTopInventory();
+                    if (packetplayinwindowclick.b() == 0 && top instanceof CraftingInventory) {
+                        org.bukkit.inventory.Recipe recipe = ((CraftingInventory) top).getRecipe();
+                        if (recipe != null) {
+                            if (click == ClickType.NUMBER_KEY) {
+                                event = new CraftItemEvent(recipe, inventory, type, packetplayinwindowclick.b(), click, action, packetplayinwindowclick.c());
+                            } else {
+                                event = new CraftItemEvent(recipe, inventory, type, packetplayinwindowclick.b(), click, action);
+                            }
+                        }
+                    }
+
+                    event.setCancelled(cancelled);
+                    Container oldContainer = this.player.activeContainer; // SPIGOT-1224
+                    server.getPluginManager().callEvent(event);
+                    if (this.player.activeContainer != oldContainer) {
+                        return;
+                    }
+
+                    switch (event.getResult()) {
+                        case ALLOW:
+                        case DEFAULT:
+                            itemstack = this.player.activeContainer.a(packetplayinwindowclick.b(), packetplayinwindowclick.c(), packetplayinwindowclick.f(), this.player);
+                            break;
+                        case DENY:
+                            /* Needs enum constructor in InventoryAction
+                            if (action.modifiesOtherSlots()) {
+
+                            } else {
+                                if (action.modifiesCursor()) {
+                                    this.player.playerConnection.sendPacket(new Packet103SetSlot(-1, -1, this.player.inventory.getCarried()));
+                                }
+                                if (action.modifiesClicked()) {
+                                    this.player.playerConnection.sendPacket(new Packet103SetSlot(this.player.activeContainer.windowId, packet102windowclick.slot, this.player.activeContainer.getSlot(packet102windowclick.slot).getItem()));
+                                }
+                            }*/
+                            switch (action) {
+                                // Modified other slots
+                                case PICKUP_ALL:
+                                case MOVE_TO_OTHER_INVENTORY:
+                                case HOTBAR_MOVE_AND_READD:
+                                case HOTBAR_SWAP:
+                                case COLLECT_TO_CURSOR:
+                                case UNKNOWN:
+                                    this.player.updateInventory(this.player.activeContainer);
+                                    break;
+                                // Modified cursor and clicked
+                                case PICKUP_SOME:
+                                case PICKUP_HALF:
+                                case PICKUP_ONE:
+                                case PLACE_ALL:
+                                case PLACE_SOME:
+                                case PLACE_ONE:
+                                case SWAP_WITH_CURSOR:
+                                    this.player.playerConnection.sendPacket(new PacketPlayOutSetSlot(-1, -1, this.player.inventory.getCarried()));
+                                    this.player.playerConnection.sendPacket(new PacketPlayOutSetSlot(this.player.activeContainer.windowId, packetplayinwindowclick.b(), this.player.activeContainer.getSlot(packetplayinwindowclick.b()).getItem()));
+                                    break;
+                                // Modified clicked only
+                                case DROP_ALL_SLOT:
+                                case DROP_ONE_SLOT:
+                                    this.player.playerConnection.sendPacket(new PacketPlayOutSetSlot(this.player.activeContainer.windowId, packetplayinwindowclick.b(), this.player.activeContainer.getSlot(packetplayinwindowclick.b()).getItem()));
+                                    break;
+                                // Modified cursor only
+                                case DROP_ALL_CURSOR:
+                                case DROP_ONE_CURSOR:
+                                case CLONE_STACK:
+                                    this.player.playerConnection.sendPacket(new PacketPlayOutSetSlot(-1, -1, this.player.inventory.getCarried()));
+                                    break;
+                                // Nothing
+                                case NOTHING:
+                                    break;
+                            }
+                            return;
+                    }
+
+                    if (event instanceof CraftItemEvent) {
+                        // Need to update the inventory on crafting to
+                        // correctly support custom recipes
+                        player.updateInventory(player.activeContainer);
+                    }
+                }
+                // CraftBukkit end
                 if (ItemStack.matches(packetplayinwindowclick.e(), itemstack)) {
                     this.player.playerConnection.sendPacket(new PacketPlayOutTransaction(packetplayinwindowclick.a(), packetplayinwindowclick.d(), true));
                     this.player.f = true;
@@ -859,6 +1861,7 @@
 
     public void a(PacketPlayInEnchantItem packetplayinenchantitem) {
         PlayerConnectionUtils.ensureMainThread(packetplayinenchantitem, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         this.player.resetIdleTimer();
         if (this.player.activeContainer.windowId == packetplayinenchantitem.a() && this.player.activeContainer.c(this.player) && !this.player.isSpectator()) {
             this.player.activeContainer.a(this.player, packetplayinenchantitem.b());
@@ -892,7 +1895,46 @@
             }
 
             boolean flag1 = packetplayinsetcreativeslot.a() >= 1 && packetplayinsetcreativeslot.a() <= 45;
-            boolean flag2 = itemstack.isEmpty() || itemstack.getData() >= 0 && itemstack.getCount() <= 64 && !itemstack.isEmpty();
+            // CraftBukkit - Add invalidItems check
+            boolean flag2 = itemstack.isEmpty() || itemstack.getData() >= 0 && itemstack.getCount() <= 64 && !itemstack.isEmpty() && !invalidItems.contains(Item.getId(itemstack.getItem()));
+            if (flag || (flag1 && !ItemStack.matches(this.player.defaultContainer.getSlot(packetplayinsetcreativeslot.a()).getItem(), packetplayinsetcreativeslot.getItemStack()))) { // Insist on valid slot
+                // CraftBukkit start - Call click event
+                org.bukkit.entity.HumanEntity player = this.player.getBukkitEntity();
+                InventoryView inventory = new CraftInventoryView(player, player.getInventory(), this.player.defaultContainer);
+                org.bukkit.inventory.ItemStack item = CraftItemStack.asBukkitCopy(packetplayinsetcreativeslot.getItemStack());
+
+                SlotType type = SlotType.QUICKBAR;
+                if (flag) {
+                    type = SlotType.OUTSIDE;
+                } else if (packetplayinsetcreativeslot.a() < 36) {
+                    if (packetplayinsetcreativeslot.a() >= 5 && packetplayinsetcreativeslot.a() < 9) {
+                        type = SlotType.ARMOR;
+                    } else {
+                        type = SlotType.CONTAINER;
+                    }
+                }
+                InventoryCreativeEvent event = new InventoryCreativeEvent(inventory, type, flag ? -999 : packetplayinsetcreativeslot.a(), item);
+                server.getPluginManager().callEvent(event);
+
+                itemstack = CraftItemStack.asNMSCopy(event.getCursor());
+
+                switch (event.getResult()) {
+                case ALLOW:
+                    // Plugin cleared the id / stacksize checks
+                    flag2 = true;
+                    break;
+                case DEFAULT:
+                    break;
+                case DENY:
+                    // Reset the slot
+                    if (packetplayinsetcreativeslot.a() >= 0) {
+                        this.player.playerConnection.sendPacket(new PacketPlayOutSetSlot(this.player.defaultContainer.windowId, packetplayinsetcreativeslot.a(), this.player.defaultContainer.getSlot(packetplayinsetcreativeslot.a()).getItem()));
+                        this.player.playerConnection.sendPacket(new PacketPlayOutSetSlot(-1, -1, ItemStack.a));
+                    }
+                    return;
+                }
+            }
+            // CraftBukkit end
 
             if (flag1 && flag2) {
                 if (itemstack.isEmpty()) {
@@ -916,6 +1958,7 @@
 
     public void a(PacketPlayInTransaction packetplayintransaction) {
         PlayerConnectionUtils.ensureMainThread(packetplayintransaction, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         Short oshort = (Short) this.k.get(this.player.activeContainer.windowId);
 
         if (oshort != null && packetplayintransaction.b() == oshort.shortValue() && this.player.activeContainer.windowId == packetplayintransaction.a() && !this.player.activeContainer.c(this.player) && !this.player.isSpectator()) {
@@ -926,6 +1969,7 @@
 
     public void a(PacketPlayInUpdateSign packetplayinupdatesign) {
         PlayerConnectionUtils.ensureMainThread(packetplayinupdatesign, this, this.player.x());
+        if (this.player.isFrozen()) return; // CraftBukkit
         this.player.resetIdleTimer();
         WorldServer worldserver = this.minecraftServer.getWorldServer(this.player.dimension);
         BlockPosition blockposition = packetplayinupdatesign.a();
@@ -942,14 +1986,30 @@
 
             if (!tileentitysign.a() || tileentitysign.e() != this.player) {
                 this.minecraftServer.warning("Player " + this.player.getName() + " just tried to change non-editable sign");
+                this.sendPacket(tileentity.getUpdatePacket()); // CraftBukkit
                 return;
             }
 
             String[] astring = packetplayinupdatesign.b();
 
+            // CraftBukkit start
+            Player player = this.server.getPlayer(this.player);
+            int x = packetplayinupdatesign.a().getX();
+            int y = packetplayinupdatesign.a().getY();
+            int z = packetplayinupdatesign.a().getZ();
+            String[] lines = new String[4];
+
             for (int i = 0; i < astring.length; ++i) {
-                tileentitysign.lines[i] = new ChatComponentText(EnumChatFormat.a(astring[i]));
+                lines[i] = EnumChatFormat.a(new ChatComponentText(EnumChatFormat.a(astring[i])).toPlainText());
             }
+            SignChangeEvent event = new SignChangeEvent((org.bukkit.craftbukkit.block.CraftBlock) player.getWorld().getBlockAt(x, y, z), this.server.getPlayer(this.player), lines);
+            this.server.getPluginManager().callEvent(event);
+
+            if (!event.isCancelled()) {
+                System.arraycopy(org.bukkit.craftbukkit.block.CraftSign.sanitizeLines(event.getLines()), 0, tileentitysign.lines, 0, 4);
+                tileentitysign.isEditable = false;
+             }
+            // CraftBukkit end
 
             tileentitysign.update();
             worldserver.notify(blockposition, iblockdata, iblockdata, 3);
@@ -972,11 +2032,27 @@
 
     public void a(PacketPlayInAbilities packetplayinabilities) {
         PlayerConnectionUtils.ensureMainThread(packetplayinabilities, this, this.player.x());
-        this.player.abilities.isFlying = packetplayinabilities.isFlying() && this.player.abilities.canFly;
+        // CraftBukkit start
+        if (this.player.abilities.canFly && this.player.abilities.isFlying != packetplayinabilities.isFlying()) {
+            PlayerToggleFlightEvent event = new PlayerToggleFlightEvent(this.server.getPlayer(this.player), packetplayinabilities.isFlying());
+            this.server.getPluginManager().callEvent(event);
+            if (!event.isCancelled()) {
+                this.player.abilities.isFlying = packetplayinabilities.isFlying(); // Actually set the player's flying status
+            } else {
+                this.player.updateAbilities(); // Tell the player their ability was reverted
+            }
+        }
+        // CraftBukkit end
     }
 
     public void a(PacketPlayInTabComplete packetplayintabcomplete) {
         PlayerConnectionUtils.ensureMainThread(packetplayintabcomplete, this, this.player.x());
+        // CraftBukkit start
+        if (chatSpamField.addAndGet(this, 10) > 500 && !this.minecraftServer.getPlayerList().isOp(this.player.getProfile())) {
+            this.disconnect("disconnect.spam");
+            return;
+        }
+        // CraftBukkit end
         ArrayList arraylist = Lists.newArrayList();
         Iterator iterator = this.minecraftServer.tabCompleteCommand(this.player, packetplayintabcomplete.a(), packetplayintabcomplete.b(), packetplayintabcomplete.c()).iterator();
 
@@ -1020,10 +2096,13 @@
                 }
 
                 if (itemstack.getItem() == Items.WRITABLE_BOOK && itemstack.getItem() == itemstack1.getItem()) {
+                    itemstack1 = new ItemStack(Items.WRITABLE_BOOK); // CraftBukkit
                     itemstack1.a("pages", (NBTBase) itemstack.getTag().getList("pages", 8));
+                    CraftEventFactory.handleEditBookEvent(player, itemstack1); // CraftBukkit
                 }
             } catch (Exception exception) {
                 PlayerConnection.LOGGER.error("Couldn\'t handle book info", exception);
+                this.disconnect("Invalid book data!"); // CraftBukkit
             }
         } else {
             String s1;
@@ -1062,10 +2141,11 @@
                         }
 
                         itemstack2.a("pages", (NBTBase) nbttaglist);
-                        this.player.setSlot(EnumItemSlot.MAINHAND, itemstack2);
+                        CraftEventFactory.handleEditBookEvent(player, itemstack2); // CraftBukkit
                     }
                 } catch (Exception exception1) {
                     PlayerConnection.LOGGER.error("Couldn\'t sign book", exception1);
+                    this.disconnect("Invalid book data!"); // CraftBukkit
                 }
             } else if ("MC|TrSel".equals(s)) {
                 try {
@@ -1077,6 +2157,7 @@
                     }
                 } catch (Exception exception2) {
                     PlayerConnection.LOGGER.error("Couldn\'t select trade", exception2);
+                    this.disconnect("Invalid trade data!"); // CraftBukkit
                 }
             } else {
                 TileEntity tileentity;
@@ -1126,6 +2207,7 @@
                         }
                     } catch (Exception exception3) {
                         PlayerConnection.LOGGER.error("Couldn\'t set command block", exception3);
+                        this.disconnect("Invalid command data!"); // CraftBukkit
                     }
                 } else if ("MC|AutoCmd".equals(s)) {
                     if (!this.minecraftServer.getEnableCommandBlock()) {
@@ -1193,6 +2275,7 @@
                         }
                     } catch (Exception exception4) {
                         PlayerConnection.LOGGER.error("Couldn\'t set command block", exception4);
+                        this.disconnect("Invalid command data!"); // CraftBukkit
                     }
                 } else {
                     int k;
@@ -1216,6 +2299,7 @@
                                 }
                             } catch (Exception exception5) {
                                 PlayerConnection.LOGGER.error("Couldn\'t set beacon", exception5);
+                                this.disconnect("Invalid beacon data!"); // CraftBukkit
                             }
                         }
                     } else if ("MC|ItemName".equals(s)) {
@@ -1302,6 +2386,7 @@
                             }
                         } catch (Exception exception6) {
                             PlayerConnection.LOGGER.error("Couldn\'t set structure block", exception6);
+                            this.disconnect("Invalid structure data!"); // CraftBukkit
                         }
                     } else if ("MC|PickItem".equals(s)) {
                         packetdataserializer = packetplayincustompayload.b();
@@ -1316,9 +2401,31 @@
                             PlayerConnection.LOGGER.error("Couldn\'t pick item", exception7);
                         }
                     }
+                    // CraftBukkit start
+                    else if (packetplayincustompayload.a().equals("REGISTER")) {
+                        String channels = packetplayincustompayload.b().toString(com.google.common.base.Charsets.UTF_8);
+                        for (String channel : channels.split("\0")) {
+                            getPlayer().addChannel(channel);
+                        }
+                    } else if (packetplayincustompayload.a().equals("UNREGISTER")) {
+                        String channels = packetplayincustompayload.b().toString(com.google.common.base.Charsets.UTF_8);
+                        for (String channel : channels.split("\0")) {
+                            getPlayer().removeChannel(channel);
+                        }
+                    } else {
+                        byte[] data = new byte[packetplayincustompayload.b().readableBytes()];
+                        packetplayincustompayload.b().readBytes(data);
+                        server.getMessenger().dispatchIncomingMessage(player.getBukkitEntity(), packetplayincustompayload.a(), data);
+                    }
+                    // CraftBukkit end
                 }
             }
         }
 
     }
+
+    // CraftBukkit start - Add "isDisconnected" method
+    public final boolean isDisconnected() {
+        return !this.player.joining && !this.networkManager.isConnected();
+    }
 }