@startuml CodeGenPipeline

title Build-time Code Generation Pipeline

skinparam activityShape octagon
skinparam defaultTextAlignment center

|Input|
start
:LeahiUnhandled.conf\n(CAN message definitions);

fork

    ' ── Pipeline A: Protobuf schema ──────────────────────────────
    |cmake|
    :generate_protobuf()\ninvokes GenerateProtobuf.py;

    |MsgUtils Python|
    :MsgData loads .conf —\nparses message names, IDs,\nfield names and types;

    |Jinja2 Templates|
    :MsgDefs_proto.jinja\nrenders LeahiMsgDefs.proto;

    |protoc|
    :protoc compiles .proto\ninto C++ stubs\n(LeahiMsgDefs.pb.h / .pb.cc);

    |CMake build|
    :pb stubs compiled\ninto MsgUtils library;

fork again

    ' ── Pipeline B: C++ message structs ─────────────────────────
    |cmake|
    :generate_msg_defs_cpp()\ninvokes GenerateMsgDefsCpp.py;

    |MsgUtils Python|
    :MsgData loads .conf —\nparses message names, IDs,\nfield names and types;

    |Jinja2 Templates|
    :MsgDefs_h.jinja renders\nLeahiMsgDefs.h\n(typed structs + toProtobuf /\nfromQByteArray + msgIdString());
    :MsgDefs_cpp.jinja renders\nLeahiMsgDefs.cpp\n(method implementations +\ncanMessageToProtobufByteArray() +\nmsgIdString() switch body);
    :MsgProtoUtils_h.jinja renders\nLeahiMsgProtoUtils.h;
    :MsgProtoUtils_cpp.jinja renders\nLeahiMsgProtoUtils.cpp;

    |CMake build|
    :MsgDefs + MsgProtoUtils compiled\ninto MsgUtils library;

fork again

    ' ── Pipeline C: Message handling INI ────────────────────────
    |cmake|
    :generate_msg_handling_ini()\ninvokes GenerateMsgHandlingIni.py;

    |MsgUtils Python|
    :MsgHandlingIni loads .conf —\nseeds each msgId with\naction=drop, topic=<empty>;
    :loadIni() merges existing\nLeahiRtMsgHandling.ini —\npreserves hand-edited\naction + topic values;

    |Jinja2 Templates|
    :MsgHandlingIni.jinja renders\nLeahiRtMsgHandling.ini\n(per-msgId: msg_id, action, topic);

end fork

|Runtime|
:LeahiRtController::loadMsgHandling()\nreads LeahiRtMsgHandling.ini at startup;
:onMessageReceive() looks up msgId\nin _msgHandling → drop / send_always /\nsend_delta policy, MQTT topic;
:canMessageToProtobufByteArray()\nconverts CAN → protobuf bytes;
:msgIdString() used in log output;
stop

note right
  Pipelines A and B are triggered by
  the MsgUtils library cmake target;
  Pipeline C is triggered by the
  LeahiRt executable cmake target.
  All three regenerate whenever
  the .conf file changes.
end note

@enduml