refactoring: ProtocolEncoder

protocol-new/src/main/java/mc/protocol/NettyAttributes.java

@@ -0,0 +1,10 @@
+package mc.protocol;
+
+import io.netty.util.AttributeKey;
+import lombok.experimental.UtilityClass;
+
+@UtilityClass
+public class NettyAttributes {
+
+	public static final AttributeKey<State> STATE = AttributeKey.newInstance("STATE");
+}

protocol-new/src/main/java/mc/protocol/codec/ProtocolEncoder.java

@@ -0,0 +1,37 @@
+package mc.protocol.codec;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.MessageToByteEncoder;
+import lombok.extern.slf4j.Slf4j;
+import mc.protocol.NettyAttributes;
+import mc.protocol.State;
+import mc.protocol.io.NetByteBuf;
+import mc.protocol.packets.ServerSidePacket;
+
+@Slf4j
+public class ProtocolEncoder extends MessageToByteEncoder<ServerSidePacket> {
+
+	@Override
+	protected void encode(ChannelHandlerContext ctx, ServerSidePacket packet, ByteBuf out) {
+		State state = ctx.channel().attr(NettyAttributes.STATE).get();
+		Integer packetId = state.getServerSidePacketId(packet.getClass());
+		if (packetId == null) {
+			log.error("Unknown send packet: State {} ; Class {}", state, packet.getClass());
+			return;
+		}
+
+		if (log.isDebugEnabled()) {
+			log.debug("OUT: {}:{}", state, packet);
+		}
+
+		NetByteBuf buffer = new NetByteBuf(Unpooled.buffer());
+		buffer.writeVarInt(packetId);
+		packet.writeSelf(buffer);
+
+		NetByteBuf netByteBuf = new NetByteBuf(out);
+		netByteBuf.writeVarInt(buffer.readableBytes());
+		netByteBuf.writeBytes(buffer);
+	}
+}