Implement ItemRewritter

Upgrade ViaIdleThread to new system
Add new method to ProtocolPipeline
Implement Use Item

src/main/java/us/myles/ViaVersion/ViaIdleThread.java

@@ -3,15 +3,19 @@ package us.myles.ViaVersion;
 import org.bukkit.scheduler.BukkitRunnable;
 import us.myles.ViaVersion.api.ViaVersion;
 import us.myles.ViaVersion.util.ReflectionUtil;
+import us.myles.ViaVersion2.api.data.UserConnection;
+import us.myles.ViaVersion2.api.protocol.base.ProtocolInfo;
+import us.myles.ViaVersion2.api.protocol1_9to1_8.Protocol1_9TO1_8;
+import us.myles.ViaVersion2.api.protocol1_9to1_8.storage.MovementTracker;
 
 import java.util.Map;
 import java.util.UUID;
 
 public class ViaIdleThread extends BukkitRunnable {
-    private final Map<UUID, ConnectionInfo> portedPlayers;
+    private final Map<UUID, UserConnection> portedPlayers;
     private final Class<?> idlePacketClass;
 
-    public ViaIdleThread(Map<UUID, ConnectionInfo> portedPlayers) {
+    public ViaIdleThread(Map<UUID, UserConnection> portedPlayers) {
         this.portedPlayers = portedPlayers;
         try {
             this.idlePacketClass = ReflectionUtil.nms("PacketPlayInFlying");
@@ -22,19 +26,21 @@ public class ViaIdleThread extends BukkitRunnable {
 
     @Override
     public void run() {
-        for(ConnectionInfo info : portedPlayers.values()) {
+        for(UserConnection info : portedPlayers.values()) {
-            long nextIdleUpdate = info.getNextIdlePacket();
+            if(info.get(ProtocolInfo.class).getPipeline().contains(Protocol1_9TO1_8.class)) {
-            if(nextIdleUpdate <= System.currentTimeMillis()) {
+                long nextIdleUpdate = info.get(MovementTracker.class).getNextIdlePacket();
-                try {
+                if (nextIdleUpdate <= System.currentTimeMillis()) {
-                    Object packet = idlePacketClass.newInstance();
+                    try {
-                    info.getChannel().pipeline().fireChannelRead(packet);
+                        Object packet = idlePacketClass.newInstance();
-                } catch(InstantiationException | IllegalAccessException e) {
+                        info.getChannel().pipeline().fireChannelRead(packet);
-                    System.out.println("Failed to create idle packet.");
+                    } catch (InstantiationException | IllegalAccessException e) {
-                    if(ViaVersion.getInstance().isDebug()) {
+                        System.out.println("Failed to create idle packet.");
-                        e.printStackTrace();
+                        if (ViaVersion.getInstance().isDebug()) {
+                            e.printStackTrace();
+                        }
+                    } finally {
+                        info.get(MovementTracker.class).incrementIdlePacket();
                     }
-                } finally {
-                    info.incrementIdlePacket();
                 }
             }
         }

src/main/java/us/myles/ViaVersion/ViaVersionPlugin.java

@@ -27,6 +27,8 @@ import us.myles.ViaVersion.update.UpdateUtil;
 import us.myles.ViaVersion.util.Configuration;
 import us.myles.ViaVersion.util.ListWrapper;
 import us.myles.ViaVersion.util.ReflectionUtil;
+import us.myles.ViaVersion2.api.data.UserConnection;
+import us.myles.ViaVersion2.api.protocol.base.ProtocolInfo;
 
 import java.io.File;
 import java.lang.reflect.Field;
@@ -41,7 +43,7 @@ import java.util.concurrent.TimeUnit;
 
 public class ViaVersionPlugin extends JavaPlugin implements ViaVersionAPI {
 
-    private final Map<UUID, ConnectionInfo> portedPlayers = new ConcurrentHashMap<>();
+    private final Map<UUID, UserConnection> portedPlayers = new ConcurrentHashMap<>();
     private boolean debug = false;
 
     public static ItemStack getHandItem(final ConnectionInfo info) {
@@ -212,7 +214,7 @@ public class ViaVersionPlugin extends JavaPlugin implements ViaVersionAPI {
     @Override
     public void sendRawPacket(UUID uuid, ByteBuf packet) throws IllegalArgumentException {
         if (!isPorted(uuid)) throw new IllegalArgumentException("This player is not on 1.9");
-        ConnectionInfo ci = portedPlayers.get(uuid);
+        UserConnection ci = portedPlayers.get(uuid);
         ci.sendRawPacket(packet);
     }
 
@@ -269,8 +271,8 @@ public class ViaVersionPlugin extends JavaPlugin implements ViaVersionAPI {
         return getConfig().getBoolean("auto-team", true);
     }
 
-    public void addPortedClient(ConnectionInfo info) {
+    public void addPortedClient(UserConnection info) {
-        portedPlayers.put(info.getUUID(), info);
+        portedPlayers.put(info.get(ProtocolInfo.class).getUuid(), info);
     }
 
     public void removePortedClient(UUID clientID) {

src/main/java/us/myles/ViaVersion/transformers/OutgoingTransformer.java

@@ -313,7 +313,7 @@ public class OutgoingTransformer {
             PacketUtil.writeString(uuid, output);
             UUID uniqueId = UUID.fromString(uuid);
             info.setUUID(uniqueId);
-            plugin.addPortedClient(info);
+           // plugin.addPortedClient(info);
             String username = PacketUtil.readString(input);
             info.setUsername(username);
             PacketUtil.writeString(username, output);

src/main/java/us/myles/ViaVersion2/api/PacketWrapper.java

@@ -94,7 +94,7 @@ public class PacketWrapper {
             System.out.println("writing: " + packetValue.getKey().getTypeName() + " value: " + packetValue.getValue() + " ID: " + getId());
             try {
                 Object value = packetValue.getValue();
-                if(value != null) {
+                if (value != null) {
                     if (!value.getClass().equals(packetValue.getKey().getOutputClass())) {
                         // attempt conversion
                         if (packetValue.getKey() instanceof TypeConverter) {
@@ -105,20 +105,25 @@ public class PacketWrapper {
                     }
                 }
                 packetValue.getKey().write(buffer, value);
-            }catch (Exception e){
+            } catch (Exception e) {
                 System.out.println(getId() + " Index: " + index + " Type: " + packetValue.getKey().getTypeName());
                 throw e;
             }
             index++;
         }
-        if(packetValues.size() != 0){
+        if (packetValues.size() != 0) {
-            if(inputBuffer != null){
+            if (inputBuffer != null) {
                 System.out.println(">> Writing remaining: " + inputBuffer.readableBytes() + " ID: " + getId());
             }
         }
         writeRemaining(buffer);
     }
 
+    public void clearInputBuffer() {
+        if (inputBuffer != null)
+            inputBuffer.clear();
+    }
+
     private void writeRemaining(ByteBuf output) {
         if (inputBuffer != null) {
             output.writeBytes(inputBuffer);

src/main/java/us/myles/ViaVersion2/api/data/UserConnection.java

@@ -14,6 +14,7 @@ public class UserConnection {
     @Getter
     @Setter
     private boolean active = true;
+    @Getter
     private final SocketChannel channel;
     @Getter
     @Setter

src/main/java/us/myles/ViaVersion2/api/protocol/ProtocolPipeline.java

@@ -62,4 +62,11 @@ public class ProtocolPipeline extends Protocol {
         super.transform(direction, state, packetWrapper);
         System.out.println("--> Sending Packet ID: " + packetWrapper.getId() + " " + state + " " + direction);
     }
+
+    public boolean contains(Class<? extends Protocol> pipeClass){
+        for(Protocol protocol:protocolList){
+            if(protocol.getClass().equals(pipeClass)) return true;
+        }
+        return false;
+    }
 }

src/main/java/us/myles/ViaVersion2/api/protocol/base/BaseProtocol.java

@@ -3,6 +3,8 @@ package us.myles.ViaVersion2.api.protocol.base;
 import org.json.simple.JSONObject;
 import org.json.simple.parser.JSONParser;
 import org.json.simple.parser.ParseException;
+import us.myles.ViaVersion.ViaVersionPlugin;
+import us.myles.ViaVersion.api.ViaVersion;
 import us.myles.ViaVersion.packets.State;
 import us.myles.ViaVersion.util.PacketUtil;
 import us.myles.ViaVersion2.api.PacketWrapper;
@@ -57,12 +59,14 @@ public class BaseProtocol extends Protocol {
                 handler(new PacketHandler() {
                     @Override
                     public void handle(PacketWrapper wrapper) {
-                        System.out.println("play state");
                         ProtocolInfo info = wrapper.user().get(ProtocolInfo.class);
                         info.setState(State.PLAY);
+                        // Save other info
                         UUID uuid = UUID.fromString(wrapper.get(Type.STRING, 0));
                         info.setUuid(uuid);
                         info.setUsername(wrapper.get(Type.STRING, 1));
+                        // Add to ported clients
+                        ((ViaVersionPlugin) ViaVersion.getInstance()).addPortedClient(wrapper.user());
                     }
                 });
             }

src/main/java/us/myles/ViaVersion2/api/protocol1_9to1_8/ItemRewriter.java

@@ -0,0 +1,251 @@
+package us.myles.ViaVersion2.api.protocol1_9to1_8;
+
+import org.bukkit.Material;
+import org.spacehq.opennbt.tag.builtin.CompoundTag;
+import org.spacehq.opennbt.tag.builtin.ListTag;
+import org.spacehq.opennbt.tag.builtin.StringTag;
+import org.spacehq.opennbt.tag.builtin.Tag;
+import us.myles.ViaVersion.transformers.OutgoingTransformer;
+import us.myles.ViaVersion2.api.item.Item;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+public class ItemRewriter {
+
+    private static final Map<String, Integer> ENTTIY_NAME_TO_ID = new HashMap<>();
+    private static final Map<Integer, String> ENTTIY_ID_TO_NAME = new HashMap<>();
+    private static final Map<String, Integer> POTION_NAME_TO_ID = new HashMap<>();
+    private static final Map<Integer, String> POTION_ID_TO_NAME = new HashMap<>();
+
+    static {
+        /* Entities */
+        registerEntity(1, "Item");
+        registerEntity(2, "XPOrb");
+        registerEntity(7, "ThrownEgg");
+        registerEntity(8, "LeashKnot");
+        registerEntity(9, "Painting");
+        registerEntity(10, "Arrow");
+        registerEntity(11, "Snowball");
+        registerEntity(12, "Fireball");
+        registerEntity(13, "SmallFireball");
+        registerEntity(14, "ThrownEnderpearl");
+        registerEntity(15, "EyeOfEnderSignal");
+        registerEntity(16, "ThrownPotion");
+        registerEntity(17, "ThrownExpBottle");
+        registerEntity(18, "ItemFrame");
+        registerEntity(19, "WitherSkull");
+        registerEntity(20, "PrimedTnt");
+        registerEntity(21, "FallingSand");
+        registerEntity(22, "FireworksRocketEntity");
+        registerEntity(30, "ArmorStand");
+        registerEntity(40, "MinecartCommandBlock");
+        registerEntity(41, "Boat");
+        registerEntity(42, "MinecartRideable");
+        registerEntity(43, "MinecartChest");
+        registerEntity(44, "MinecartFurnace");
+        registerEntity(45, "MinecartTNT");
+        registerEntity(46, "MinecartHopper");
+        registerEntity(47, "MinecartSpawner");
+        registerEntity(48, "Mob");
+        registerEntity(49, "Monster");
+        registerEntity(50, "Creeper");
+        registerEntity(51, "Skeleton");
+        registerEntity(52, "Spider");
+        registerEntity(53, "Giant");
+        registerEntity(54, "Zombie");
+        registerEntity(55, "Slime");
+        registerEntity(56, "Ghast");
+        registerEntity(57, "PigZombie");
+        registerEntity(58, "Enderman");
+        registerEntity(59, "CaveSpider");
+        registerEntity(60, "Silverfish");
+        registerEntity(61, "Blaze");
+        registerEntity(62, "LavaSlime");
+        registerEntity(63, "EnderDragon");
+        registerEntity(64, "WitherBoss");
+        registerEntity(65, "Bat");
+        registerEntity(66, "Witch");
+        registerEntity(67, "Endermite");
+        registerEntity(68, "Guardian");
+        registerEntity(90, "Pig");
+        registerEntity(91, "Sheep");
+        registerEntity(92, "Cow");
+        registerEntity(93, "Chicken");
+        registerEntity(94, "Squid");
+        registerEntity(95, "Wolf");
+        registerEntity(96, "MushroomCow");
+        registerEntity(97, "SnowMan");
+        registerEntity(98, "Ozelot");
+        registerEntity(99, "VillagerGolem");
+        registerEntity(100, "EntityHorse");
+        registerEntity(101, "Rabbit");
+        registerEntity(120, "Villager");
+        registerEntity(200, "EnderCrystal");
+
+        /* Potions */
+        registerPotion(0, "water");
+        registerPotion(64, "mundane");
+        registerPotion(32, "thick");
+        registerPotion(16, "awkward");
+
+        registerPotion(8198, "night_vision");
+        registerPotion(8262, "long_night_vision");
+
+        registerPotion(8206, "invisibility");
+        registerPotion(8270, "long_invisibility");
+
+        registerPotion(8203, "leaping");
+        registerPotion(8267, "long_leaping");
+        registerPotion(8235, "strong_leaping");
+
+        registerPotion(8195, "fire_resistance");
+        registerPotion(8259, "long_fire_resistance");
+
+        registerPotion(8194, "swiftness");
+        registerPotion(8258, "long_swiftness");
+        registerPotion(8226, "strong_swiftness");
+
+        registerPotion(8202, "slowness");
+        registerPotion(8266, "long_slowness");
+
+        registerPotion(8205, "water_breathing");
+        registerPotion(8269, "long_water_breathing");
+
+        registerPotion(8197, "healing");
+        registerPotion(8229, "strong_healing");
+
+        registerPotion(8204, "harming");
+        registerPotion(8236, "strong_harming");
+
+        registerPotion(8196, "poison");
+        registerPotion(8260, "long_poison");
+        registerPotion(8228, "strong_poison");
+
+        registerPotion(8193, "regeneration");
+        registerPotion(8257, "long_regeneration");
+        registerPotion(8225, "strong_regeneration");
+
+        registerPotion(8201, "strength");
+        registerPotion(8265, "long_strength");
+        registerPotion(8233, "strong_strength");
+
+        registerPotion(8200, "weakness");
+        registerPotion(8264, "long_weakness");
+
+    }
+
+    public static void toServer(Item item) {
+        if (item != null) {
+            if (item.getId() == Material.MONSTER_EGG.getId() && item.getData() == 0) {
+                CompoundTag tag = item.getTag();
+                int data = 0;
+                if (tag != null && tag.get("EntityTag") instanceof CompoundTag) {
+                    CompoundTag entityTag = tag.get("EntityTag");
+                    if (entityTag.get("id") instanceof StringTag) {
+                        StringTag id = entityTag.get("id");
+                        if (ENTTIY_NAME_TO_ID.containsKey(id.getValue()))
+                            data = ENTTIY_NAME_TO_ID.get(id.getValue());
+                    }
+                }
+                item.setTag(null);
+                item.setData((short) data);
+            }
+            if (item.getId() == Material.POTION.getId()) {
+                CompoundTag tag = item.getTag();
+                int data = 0;
+                if (tag != null && tag.get("Potion") instanceof StringTag) {
+                    StringTag potion = tag.get("Potion");
+                    String potionName = potion.getValue().replace("minecraft:", "");
+                    if (POTION_NAME_TO_ID.containsKey(potionName)) {
+                        data = POTION_NAME_TO_ID.get(potionName);
+                    }
+                }
+                item.setTag(null);
+                item.setData((short) data);
+            }
+            if (item.getId() == 438) {
+                CompoundTag tag = item.getTag();
+                int data = 0;
+                item.setId((short) Material.POTION.getId());
+                if (tag != null && tag.get("Potion") instanceof StringTag) {
+                    StringTag potion = tag.get("Potion");
+                    String potionName = potion.getValue().replace("minecraft:", "");
+                    if (POTION_NAME_TO_ID.containsKey(potionName)) {
+                        data = POTION_NAME_TO_ID.get(potionName) + 8192;
+                    }
+                }
+                item.setTag(null);
+                item.setData((short) data);
+            }
+        }
+    }
+
+    public static void toClient(Item item) {
+        if (item != null) {
+            if (item.getId() == Material.MONSTER_EGG.getId() && item.getData() != 0) {
+                CompoundTag tag = item.getTag();
+                if (tag == null) {
+                    tag = new CompoundTag("tag");
+                }
+                CompoundTag entityTag = new CompoundTag("EntityTag");
+                if (ENTTIY_ID_TO_NAME.containsKey((int) item.getData())) {
+                    StringTag id = new StringTag("id", ENTTIY_ID_TO_NAME.get((int) item.getData()));
+                    entityTag.put(id);
+                    tag.put(entityTag);
+                }
+                item.setTag(tag);
+                item.setData((short) 0);
+            }
+            if (item.getId() == Material.POTION.getId()) {
+                CompoundTag tag = item.getTag();
+                if (tag == null) {
+                    tag = new CompoundTag("tag");
+                }
+                if (item.getData() >= 16384) {
+                    item.setId((short) 438); // splash id
+                    item.setData((short) (item.getData() - 8192));
+                }
+                if (POTION_ID_TO_NAME.containsKey((int) item.getData())) {
+                    String name = POTION_ID_TO_NAME.get((int) item.getData());
+                    StringTag potion = new StringTag("Potion", "minecraft:" + name);
+                    tag.put(potion);
+                }
+                item.setTag(tag);
+                item.setData((short) 0);
+            }
+            if (item.getId() == Material.WRITTEN_BOOK.getId()) {
+                CompoundTag tag = item.getTag();
+                if (tag == null) {
+                    tag = new CompoundTag("tag");
+                }
+                ListTag pages = tag.get("pages");
+                if (pages == null) {
+                    pages = new ListTag("pages", Collections.<Tag>singletonList(new StringTag(OutgoingTransformer.fixJson(""))));
+                    tag.put(pages);
+                    item.setTag(tag);
+                    return;
+                }
+
+                for (int i = 0; i < pages.size(); i++) {
+                    if (!(pages.get(i) instanceof StringTag))
+                        continue;
+                    StringTag page = pages.get(i);
+                    page.setValue(OutgoingTransformer.fixJson(page.getValue()));
+                }
+                item.setTag(tag);
+            }
+        }
+    }
+
+    private static void registerEntity(Integer id, String name) {
+        ENTTIY_ID_TO_NAME.put(id, name);
+        ENTTIY_NAME_TO_ID.put(name, id);
+    }
+
+    private static void registerPotion(Integer id, String name) {
+        POTION_ID_TO_NAME.put(id, name);
+        POTION_NAME_TO_ID.put(name, id);
+    }
+}

src/main/java/us/myles/ViaVersion2/api/protocol1_9to1_8/PlayerMovementMapper.java

@@ -0,0 +1,18 @@
+package us.myles.ViaVersion2.api.protocol1_9to1_8;
+
+import us.myles.ViaVersion2.api.PacketWrapper;
+import us.myles.ViaVersion2.api.protocol1_9to1_8.storage.MovementTracker;
+import us.myles.ViaVersion2.api.remapper.PacketHandler;
+import us.myles.ViaVersion2.api.remapper.PacketRemapper;
+
+public class PlayerMovementMapper extends PacketRemapper {
+    @Override
+    public void registerMap() {
+        handler(new PacketHandler() {
+            @Override
+            public void handle(PacketWrapper wrapper) throws Exception {
+                wrapper.user().get(MovementTracker.class).incrementIdlePacket();
+            }
+        });
+    }
+}

src/main/java/us/myles/ViaVersion2/api/protocol1_9to1_8/Protocol1_9TO1_8.java

@@ -9,6 +9,7 @@ import us.myles.ViaVersion2.api.protocol.Protocol;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.packets.*;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.storage.ClientChunks;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.storage.EntityTracker;
+import us.myles.ViaVersion2.api.protocol1_9to1_8.storage.MovementTracker;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.types.MetadataListType;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.types.MetadataType;
 import us.myles.ViaVersion2.api.remapper.ValueTransformer;
@@ -61,5 +62,7 @@ public class Protocol1_9TO1_8 extends Protocol {
         userConnection.put(new EntityTracker());
         // Chunk tracker
         userConnection.put(new ClientChunks());
+        // Movement tracker
+        userConnection.put(new MovementTracker());
     }
 }

src/main/java/us/myles/ViaVersion2/api/protocol1_9to1_8/packets/EntityPackets.java

@@ -4,8 +4,10 @@ import us.myles.ViaVersion.ViaVersionPlugin;
 import us.myles.ViaVersion.api.ViaVersion;
 import us.myles.ViaVersion.packets.State;
 import us.myles.ViaVersion2.api.PacketWrapper;
+import us.myles.ViaVersion2.api.item.Item;
 import us.myles.ViaVersion2.api.metadata.Metadata;
 import us.myles.ViaVersion2.api.protocol.Protocol;
+import us.myles.ViaVersion2.api.protocol1_9to1_8.ItemRewriter;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.Protocol1_9TO1_8;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.metadata.MetadataRewriter;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.storage.EntityTracker;
@@ -172,7 +174,13 @@ public class EntityPackets {
 
                 // TODO - Blocking patch
 
-                // TODO - ItemStack rewriter
+                handler(new PacketHandler() {
+                    @Override
+                    public void handle(PacketWrapper wrapper) throws Exception {
+                        Item stack = wrapper.get(Type.ITEM, 0);
+                        ItemRewriter.toClient(stack);
+                    }
+                });
             }
         });
         // Entity Metadata Packet

src/main/java/us/myles/ViaVersion2/api/protocol1_9to1_8/packets/InventoryPackets.java

@@ -2,7 +2,9 @@ package us.myles.ViaVersion2.api.protocol1_9to1_8.packets;
 
 import us.myles.ViaVersion.packets.State;
 import us.myles.ViaVersion2.api.PacketWrapper;
+import us.myles.ViaVersion2.api.item.Item;
 import us.myles.ViaVersion2.api.protocol.Protocol;
+import us.myles.ViaVersion2.api.protocol1_9to1_8.ItemRewriter;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.Protocol1_9TO1_8;
 import us.myles.ViaVersion2.api.remapper.PacketHandler;
 import us.myles.ViaVersion2.api.remapper.PacketRemapper;
@@ -47,7 +49,13 @@ public class InventoryPackets {
                 map(Type.SHORT); // 1 - Slot ID
                 map(Type.ITEM); // 2 - Slot Value
                 // TODO Brewing patch
-                // TODO - ItemStack rewriter
+                handler(new PacketHandler() {
+                    @Override
+                    public void handle(PacketWrapper wrapper) throws Exception {
+                        Item stack = wrapper.get(Type.ITEM, 0);
+                        ItemRewriter.toClient(stack);
+                    }
+                });
             }
         });
         // Window Set Slots Packet
@@ -59,7 +67,14 @@ public class InventoryPackets {
                 map(Type.ITEM_ARRAY); // 1 - Window Values
 
                 // TODO Brewing patch
-                // TODO - ItemStack rewriter
+                handler(new PacketHandler() {
+                    @Override
+                    public void handle(PacketWrapper wrapper) throws Exception {
+                        Item[] stacks = wrapper.get(Type.ITEM_ARRAY, 0);
+                        for (Item stack : stacks)
+                            ItemRewriter.toClient(stack);
+                    }
+                });
             }
         });
         // Close Window Packet
@@ -103,7 +118,13 @@ public class InventoryPackets {
             public void registerMap() {
                 map(Type.SHORT);
                 map(Type.ITEM);
-                // TODO: Transform Item Patch
+                handler(new PacketHandler() {
+                    @Override
+                    public void handle(PacketWrapper wrapper) throws Exception {
+                        Item stack = wrapper.get(Type.ITEM, 0);
+                        ItemRewriter.toServer(stack);
+                    }
+                });
             }
         });
 
@@ -118,7 +139,13 @@ public class InventoryPackets {
                 map(Type.SHORT);
                 map(Type.BYTE);
                 map(Type.ITEM);
-                // TODO: Transform Item Patch
+                handler(new PacketHandler() {
+                    @Override
+                    public void handle(PacketWrapper wrapper) throws Exception {
+                        Item stack = wrapper.get(Type.ITEM, 0);
+                        ItemRewriter.toServer(stack);
+                    }
+                });
                 // TODO: Throw elytra and brewing patch
             }
         });
@@ -132,10 +159,6 @@ public class InventoryPackets {
             }
         });
 
-
-
-        // TODO Use Item
-
         /* Packets which do not have any field remapping or handlers */
 
         protocol.registerIncoming(State.PLAY, 0x0F, 0x05); // Confirm Transaction Packet

src/main/java/us/myles/ViaVersion2/api/protocol1_9to1_8/packets/PlayerPackets.java

@@ -6,6 +6,7 @@ import us.myles.ViaVersion.api.ViaVersion;
 import us.myles.ViaVersion.packets.State;
 import us.myles.ViaVersion2.api.PacketWrapper;
 import us.myles.ViaVersion2.api.protocol.Protocol;
+import us.myles.ViaVersion2.api.protocol1_9to1_8.PlayerMovementMapper;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.Protocol1_9TO1_8;
 import us.myles.ViaVersion2.api.protocol1_9to1_8.storage.EntityTracker;
 import us.myles.ViaVersion2.api.remapper.PacketHandler;
@@ -225,8 +226,6 @@ public class PlayerPackets {
         protocol.registerOutgoing(State.PLAY, 0x06, 0x3E); // Update Health Packet
         protocol.registerOutgoing(State.PLAY, 0x0D, 0x49); // Collect Item Packet
 
-        protocol.registerOutgoing(State.PLAY, 0x3F, 0x18); // Plugin Message
-
         // TODO:
         // Server Difficulty - Activate Auto-Team
 
@@ -301,16 +300,28 @@ public class PlayerPackets {
             }
         });
 
-        // Use Item TODO
+        // Use Item Packet
         protocol.registerIncoming(State.PLAY, -1, 0x1D, new PacketRemapper() {
             @Override
             public void registerMap() {
                 handler(new PacketHandler() {
                     @Override
                     public void handle(PacketWrapper wrapper) throws Exception {
-                        wrapper.cancel();
+                        // Wipe the input buffer
+                        wrapper.clearInputBuffer();
+                        // First set this packet ID to Block placement
+                        wrapper.setId(0x08);
+                        wrapper.write(Type.LONG, -1L);
+                        wrapper.write(Type.BYTE, (byte) 255);
+                        // Write item in hand
+                        wrapper.write(Type.SHORT, (short) -1); // TODO
+
+                        wrapper.write(Type.BYTE, (byte) 0);
+                        wrapper.write(Type.BYTE, (byte) 0);
+                        wrapper.write(Type.BYTE, (byte) 0);
                     }
                 });
+
             }
         });
 
@@ -323,10 +334,10 @@ public class PlayerPackets {
 
         protocol.registerIncoming(State.PLAY, 0x00, 0x0B); // Keep Alive Request Packet
 
-        protocol.registerIncoming(State.PLAY, 0x04, 0x0C); // Player Position Packet
+        protocol.registerIncoming(State.PLAY, 0x04, 0x0C, new PlayerMovementMapper()); // Player Position Packet
-        protocol.registerIncoming(State.PLAY, 0x06, 0x0D); // Player Move & Look Packet
+        protocol.registerIncoming(State.PLAY, 0x06, 0x0D, new PlayerMovementMapper()); // Player Move & Look Packet
-        protocol.registerIncoming(State.PLAY, 0x05, 0x0E); // Player Look Packet
+        protocol.registerIncoming(State.PLAY, 0x05, 0x0E, new PlayerMovementMapper()); // Player Look Packet
-        protocol.registerIncoming(State.PLAY, 0x03, 0x0F); // Player Packet
+        protocol.registerIncoming(State.PLAY, 0x03, 0x0F, new PlayerMovementMapper()); // Player Packet
 
         // TODO Plugin Channels :(
         protocol.registerIncoming(State.PLAY, 0x17, 0x09); // plugin message incoming

src/main/java/us/myles/ViaVersion2/api/protocol1_9to1_8/packets/SpawnPackets.java

@@ -170,7 +170,7 @@ public class SpawnPackets {
                 map(Type.SHORT); // 11 - Velocity Z
 
                 map(Protocol1_9TO1_8.METADATA_LIST);
-
+                // TODO: Metadata detector for bossbars, wither stuff.
                 handler(new PacketHandler() {
                     @Override
                     public void handle(PacketWrapper wrapper) throws Exception {
@@ -267,7 +267,6 @@ public class SpawnPackets {
                         for (Integer entity : entities) {
                             // EntityTracker
                             wrapper.user().get(EntityTracker.class).removeEntity(entity);
-                            // TODO: When holograms added and bossbars, remove too
                         }
                     }
                 });

src/main/java/us/myles/ViaVersion2/api/protocol1_9to1_8/storage/MovementTracker.java

@@ -0,0 +1,17 @@
+package us.myles.ViaVersion2.api.protocol1_9to1_8.storage;
+
+import lombok.Getter;
+import us.myles.ViaVersion2.api.data.StoredObject;
+
+public class MovementTracker extends StoredObject{
+    private static final long IDLE_PACKET_DELAY = 50L; // Update every 50ms (20tps)
+    private static final long IDLE_PACKET_LIMIT = 20; // Max 20 ticks behind
+    @Getter
+    private long nextIdlePacket = 0L;
+
+    public void incrementIdlePacket() {
+        // Notify of next update
+        // Allow a maximum lag spike of 1 second (20 ticks/updates)
+        this.nextIdlePacket = Math.max(nextIdlePacket + IDLE_PACKET_DELAY, System.currentTimeMillis() - IDLE_PACKET_DELAY * IDLE_PACKET_LIMIT);
+    }
+}

src/main/java/us/myles/ViaVersion2/api/type/types/ByteType.java

@@ -24,6 +24,10 @@ public class ByteType extends Type<Byte> implements TypeConverter<Byte> {
         if (o instanceof Number) {
             return ((Number) o).byteValue();
         }
+        if(o instanceof Boolean){
+            if(o == true) return 1;
+            if(o == false) return 0;
+        }
         return (Byte) o;
     }
 }