revert ordering logic in writeToXml()

Author: RhysMcK

src/xml_parsing.cpp

@@ -1064,8 +1064,32 @@ void addNodeModelToXML(const TreeNodeManifest& model, XMLDocument& doc,
   XMLElement* element = doc.NewElement(toStr(model.type).c_str());
   element->SetAttribute("ID", model.registration_ID.c_str());
 
-  for(const auto& [port_name, port_info] : model.ports)
+  std::vector<std::string> ordered_ports;
+  PortDirection const directions[3] = {PortDirection::INPUT,
+                                       PortDirection::OUTPUT,
+                                       PortDirection::INOUT};
+  for (PortDirection direction: directions)
   {
+    std::set<std::string> port_names;
+    for (auto& port : model.ports)
+    {
+      const auto& port_name = port.first;
+      const auto& port_info = port.second;
+      if (port_info.direction() == direction)
+      {
+        port_names.insert(port_name);
+      }
+    }
+    for (auto& port : port_names)
+    {
+      ordered_ports.push_back(port);
+    }
+  }
+
+  for (const auto& port_name : ordered_ports)
+  {
+    const auto& port_info = model.ports.at(port_name);
+
     XMLElement* port_element = nullptr;
     switch(port_info.direction())
     {
@@ -1544,4 +1568,4 @@ std::string WriteTreeToXML(const Tree& tree, bool add_metadata, bool add_builtin
   return std::string(printer.CStr(), size_t(printer.CStrSize() - 1));
 }
 
-}  // namespace BT
+}  // namespace BT