fix slot parsing

lib/parser.js

@@ -324,29 +324,31 @@ function readBool(buffer, offset) {
 function readSlot(buffer, offset) {
   var results = readShort(buffer, offset);
   if (! results) return null;
-
   var blockId = results.value;
+  var cursor = offset + results.size;
+
   if (blockId === -1) {
     return {
       value: { id: blockId },
-      size: results.size,
+      size: cursor - offset,
     };
   }
 
-  var cursor = offset + results.size;
   results = readByte(buffer, cursor);
   if (! results) return null;
   var itemCount = results.value;
-
   cursor += results.size;
+
   results = readShort(buffer, cursor);
   if (! results) return null;
   var itemDamage = results.value;
-
   cursor += results.size;
+
   results = readShort(buffer, cursor);
   if (! results) return null;
   var nbtDataSize = results.value;
+  cursor += results.size;
+
   if (nbtDataSize === -1) nbtDataSize = 0;
   var nbtDataEnd = cursor + nbtDataSize;
   var nbtData = buffer.slice(cursor, nbtDataEnd);

packets.json

@@ -217,6 +217,16 @@
       "type": "entityMetadata"
     }
   ],
+  "40": [
+    {
+      "name": "eid",
+      "type": "int"
+    },
+    {
+      "name": "metadata",
+      "type": "entityMetadata"
+    }
+  ],
   "56": [
     {
       "name": "data",