basic packet structure

include/sp/Message.h

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <memory>
+#include <vector>
+
+#include <sp/common/DataBuffer.h>
+
+namespace sp {
+class Handler;
+
+class Message {
+  public:
+	virtual ~Message() {}
+
+	void Write(DataBuffer& buffer) const {
+		buffer << GetId();
+		WriteImpl(buffer);
+	}
+
+	void Read(const DataBuffer& buffer) {
+		ReadImpl(buffer);
+	}
+
+	void Dispatch(Handler& handler) {
+		DispatchImpl(handler);
+	}
+
+	virtual int GetId() const = 0;
+
+	virtual std::string_view GetName() const = 0;
+
+  protected:
+	virtual void DispatchImpl(Handler& handler) = 0;
+	virtual void WriteImpl(DataBuffer& buffer) const = 0;
+	virtual void ReadImpl(const DataBuffer& buffer) = 0;
+};
+
+}  // namespace sp