carpet client synchronizations and protocols

src/main/java/carpet/network/ServerNetworkHandler.java

@@ -0,0 +1,123 @@
+package carpet.network;
+
+import carpet.CarpetServer;
+import carpet.CarpetSettings;
+import carpet.helpers.TickSpeed;
+import carpet.settings.ParsedRule;
+import io.netty.buffer.Unpooled;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.network.packet.s2c.play.CustomPayloadS2CPacket;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.util.PacketByteBuf;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class ServerNetworkHandler
+{
+    private static List<ServerPlayerEntity> carpetPlayers = new ArrayList<>();
+
+    public static void handleData(PacketByteBuf data, ServerPlayerEntity player)
+    {
+        if (data != null)
+        {
+            int id = data.readVarInt();
+            if (id == CarpetClient.HELLO)
+                onHello(player, data);
+        }
+    }
+    public static void onPlayerJoin(ServerPlayerEntity playerEntity)
+    {
+        if (!playerEntity.networkHandler.connection.isLocal())
+        {
+            playerEntity.networkHandler.sendPacket(new CustomPayloadS2CPacket(
+                    CarpetClient.CARPET_CHANNEL,
+                    (new PacketByteBuf(Unpooled.buffer())).writeVarInt(CarpetClient.HI).writeString(CarpetSettings.carpetVersion)
+            ));
+        }
+    }
+
+    public static void onHello(ServerPlayerEntity playerEntity, PacketByteBuf packetData)
+    {
+        carpetPlayers.add(playerEntity);
+        String clientVersion = packetData.readString(64);
+        if (clientVersion.equals(CarpetSettings.carpetVersion))
+            CarpetSettings.LOG.info("Player "+playerEntity.getName().getString()+" joined with a matching carpet client");
+        else
+            CarpetSettings.LOG.warn("Player "+playerEntity.getName().getString()+" joined with another carpet version: "+clientVersion);
+        DataBuilder data = DataBuilder.create().withTickRate();
+        CarpetServer.settingsManager.getRules().forEach(data::withRule);
+        playerEntity.networkHandler.sendPacket(new CustomPayloadS2CPacket(CarpetClient.CARPET_CHANNEL, data.build() ));
+    }
+    
+    public static void updateRuleWithConnectedClients(ParsedRule<?> rule)
+    {
+        for (ServerPlayerEntity player : carpetPlayers)
+        {
+            player.networkHandler.sendPacket(new CustomPayloadS2CPacket(
+                    CarpetClient.CARPET_CHANNEL,
+                    DataBuilder.create().withRule(rule).build()
+            ));
+        }
+    }
+    
+    public static void updateTickSpeedToConnectedPlayers()
+    {
+        for (ServerPlayerEntity player : carpetPlayers)
+        {
+            player.networkHandler.sendPacket(new CustomPayloadS2CPacket(
+                    CarpetClient.CARPET_CHANNEL,
+                    DataBuilder.create().withTickRate().build()
+            ));
+        }
+    }
+
+    public static void onPlayerLoggedOut(ServerPlayerEntity player)
+    {
+        if (!player.networkHandler.connection.isLocal())
+            carpetPlayers.remove(player);
+    }
+
+    public static void close()
+    {
+        carpetPlayers.clear();
+    }
+
+    private static class DataBuilder
+    {
+        private CompoundTag tag;
+        private static DataBuilder create()
+        {
+            return new DataBuilder();
+        }
+        private DataBuilder()
+        {
+            tag = new CompoundTag();
+        }
+        private DataBuilder withTickRate()
+        {
+            tag.putFloat("TickRate", TickSpeed.tickrate);
+            return this;
+        }
+        private DataBuilder withRule(ParsedRule<?> rule)
+        {
+            CompoundTag rules = (CompoundTag) tag.get("Rules");
+            if (rules == null)
+            {
+                rules = new CompoundTag();
+                tag.put("Rules", rules);
+            }
+            CompoundTag ruleNBT = new CompoundTag();
+            ruleNBT.putString("Value", rule.getAsString());
+            rules.put(rule.name, ruleNBT);
+            return this;
+        }
+        private PacketByteBuf build()
+        {
+            PacketByteBuf packetBuf = new PacketByteBuf(Unpooled.buffer());
+            packetBuf.writeVarInt(CarpetClient.DATA);
+            packetBuf.writeCompoundTag(tag);
+            return packetBuf;
+        }
+    }
+}