client/state: Rework packet handling to use lambda functions

src/client/state.cpp

@@ -10,11 +10,17 @@
 #include "interface/fs.h"
 #include <cereal/archives/portable_binary.hpp>
 #include <cereal/types/string.hpp>
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstrict-aliasing"
+#include <Scene.h>
+#include <MemoryBuffer.h>
+#pragma GCC diagnostic pop
 #include <cstring>
 #include <fstream>
 #include <deque>
 #include <sys/socket.h>
 #define MODULE "__state"
+namespace magic = Urho3D;
 
 extern client::Config g_client_config;
 
@@ -36,6 +42,7 @@ struct CState: public State
 	// In actuality the whole client application has to be recreated because
 	// otherwise unwanted Lua state remains.
 	bool m_connected = false;
+	sm_<ss_, std::function<void(const ss_&, const ss_&)>> m_packet_handlers;
 
 	CState(sp_<app::App> app):
 		m_socket(interface::createTCPSocket()),
@@ -47,6 +54,8 @@ struct CState: public State
 		auto *fs = interface::getGlobalFilesystem();
 		fs->create_directories(m_remote_cache_path);
 		fs->create_directories(m_tmp_path);
+
+		setup_packet_handlers();
 	}
 
 	void update()
@@ -148,20 +157,35 @@ struct CState: public State
 		});
 	}
 
+	void setup_packet_handlers();
+
 	void handle_packet(const ss_ &packet_name, const ss_ &data)
 	{
-		if(packet_name.substr(0, 5) != "core:"){
+		auto it = m_packet_handlers.find(packet_name);
+		if(it == m_packet_handlers.end()){
+			// Pass forward
 			m_app->handle_packet(packet_name, data);
-			return;
+		} else {
+			// Use handler
+			auto &handler = it->second;
+			handler(packet_name, data);
 		}
+	}
+};
 
-		if(packet_name == "core:run_script"){
+void CState::setup_packet_handlers()
+{
+	m_packet_handlers["core:run_script"] =
+			[this](const ss_ &packet_name, const ss_ &data)
+	{
 		log_i(MODULE, "Asked to run script:\n----\n%s\n----", cs(data));
 		if(m_app)
 			m_app->run_script(data);
-			return;
+	};
-		}
+
-		if(packet_name == "core:announce_file"){
+	m_packet_handlers["core:announce_file"] =
+			[this](const ss_ &packet_name, const ss_ &data)
+	{
 		ss_ file_name;
 		ss_ file_hash;
 		std::istringstream is(data, std::ios::binary);
@@ -211,17 +235,21 @@ struct CState: public State
 			send_packet("core:request_file", os.str());
 			m_waiting_files.insert(file_name);
 		}
-			return;
+	};
-		}
+
-		if(packet_name == "core:tell_after_all_files_transferred"){
+	m_packet_handlers["core:tell_after_all_files_transferred"] =
+			[this](const ss_ &packet_name, const ss_ &data)
+	{
 		if(m_waiting_files.empty()){
 			send_packet("core:all_files_transferred", "");
 		} else {
 			m_tell_after_all_files_transferred_requested = true;
 		}
-			return;
+	};
-		}
+
-		if(packet_name == "core:file_content"){
+	m_packet_handlers["core:file_content"] =
+			[this](const ss_ &packet_name, const ss_ &data)
+	{
 		ss_ file_name;
 		ss_ file_hash;
 		ss_ file_content;
@@ -260,13 +288,20 @@ struct CState: public State
 		// Let Lua resource wrapper know that this happened so it can update
 		// the copy made for Urho3D's resource cache
 		m_app->file_updated_in_cache(file_name, file_hash, path);
-			return;
+	};
-		}
+
-		if(packet_name == "entitysync:new_node"){
+	m_packet_handlers["entitysync:new_node"] =
+			[this](const ss_ &packet_name, const ss_ &data)
+	{
 		// TODO
-		}
+		magic::Scene *scene = m_app->get_scene();
-	}
+	};
-};
+
+	m_packet_handlers[""] =
+			[this](const ss_ &packet_name, const ss_ &data)
+	{
+	};
+}
 
 State* createState(sp_<app::App> app)
 {