Lazily get names from UUIDs

Instead of doing the UUID->name resolution for all players in every
case, only do it when EntityId is accessed and the name hasn't been
retrieved this run already. This makes genPOI usable for people who
have many players on their servers but don't wish to use player POI
while still using other genPOI features.

To do this, a PlayerDict has been created, which contains a dirty
hack to see if the requested item is EntityId and whether it hasn't
been set already.

overviewer_core/aux_files/genPOI.py

@@ -117,6 +117,27 @@ def handleEntities(rset, outputdir, render, rname, config):
 
     logging.info("Done.")
 
+class PlayerDict(dict):
+    use_uuid = False
+    _name = ''
+    def __getitem__(self, item):
+        if item == "EntityId":
+            if not super(PlayerDict, self).has_key("EntityId"):
+                if self.use_uuid:
+                    super(PlayerDict, self).__setitem__("EntityId", self.get_name_from_uuid())
+                else:
+                    super(PlayerDict, self).__setitem__("EntityId", self._name)
+        
+        return super(PlayerDict, self).__getitem__(item)
+
+    def get_name_from_uuid(self):
+        try:
+            profile = json.loads(urllib2.urlopen(UUID_LOOKUP_URL + self._name.replace('-','')).read())
+            if 'name' in profile:
+                return profile['name']
+        except (ValueError, urllib2.URLError):
+            logging.warning("Unable to get player name for UUID %s", playername)
+
 def handlePlayers(rset, render, worldpath):
     if not hasattr(rset, "_pois"):
         rset._pois = dict(TileEntities=[], Entities=[])
@@ -153,37 +174,35 @@ def handlePlayers(rset, render, worldpath):
     rset._pois['Players'] = []
     for playerfile in playerfiles:
         try:
-            data = nbt.load(os.path.join(playerdir, playerfile))[1]
+            data = PlayerDict(nbt.load(os.path.join(playerdir, playerfile))[1])
+            data.use_uuid = useUUIDs
             if isSinglePlayer:
                 data = data['Data']['Player']
         except IOError:
             logging.warning("Skipping bad player dat file %r", playerfile)
             continue
         playername = playerfile.split(".")[0]
-        if useUUIDs:
+
-            try:
-                profile = json.loads(urllib2.urlopen(UUID_LOOKUP_URL + playername.replace('-','')).read())
-                if 'name' in profile:
-                    playername = profile['name']
-            except (ValueError, urllib2.URLError):
-                logging.warning("Unable to get player name for UUID %s", playername)
         if isSinglePlayer:
             playername = 'Player'
+
+        data._name = playername
+
         if data['Dimension'] == dimension:
             # Position at last logout
             data['id'] = "Player"
-            data['EntityId'] = playername
             data['x'] = int(data['Pos'][0])
             data['y'] = int(data['Pos'][1])
             data['z'] = int(data['Pos'][2])
             rset._pois['Players'].append(data)
         if "SpawnX" in data and dimension == 0:
             # Spawn position (bed or main spawn)
-            spawn = {"id": "PlayerSpawn",
+            spawn = PlayerDict()
-                     "EntityId": playername,
+            spawn._name = playername
-                     "x": data['SpawnX'],
+            spawn["id"] = "PlayerSpawn"
-                     "y": data['SpawnY'],
+            spawn["x"] = data['SpawnX']
-                     "z": data['SpawnZ']}
+            spawn["y"] = data['SpawnY']
+            spawn["z"] = data['SpawnZ']
             rset._pois['Players'].append(spawn)
 
 def handleManual(rset, manualpois):