From 7d49c3c1220c82cc0541e9ba1d4267bd6833bf0a Mon Sep 17 00:00:00 2001
From: "Timur A. Fatkhullin" <timur@sao.ru>
Date: Wed, 4 Jun 2025 11:37:53 +0300
Subject: [PATCH] ...

---
 cxx/mcc_finite_state_machine.h | 83 ++++++++++++++++++++++++++++++++--
 cxx/tests/fsm_test.cpp         | 40 +++++++++++++++-
 2 files changed, 117 insertions(+), 6 deletions(-)

diff --git a/cxx/mcc_finite_state_machine.h b/cxx/mcc_finite_state_machine.h
index c82ac96..15df69e 100644
--- a/cxx/mcc_finite_state_machine.h
+++ b/cxx/mcc_finite_state_machine.h
@@ -347,7 +347,7 @@ protected:
     template <traits::fsm_tuple_of_events_c EvTplT, typename FT, size_t... Is>
     void setupInstanceFuncs(FT&& func, std::index_sequence<Is...>)
     {
-        ((_dispatchEventFunc<std::tuple_element_t<Is, EvTplT>>[this] = std::forward<FT>(func)), ...);
+        (_dispatchEventFunc<std::tuple_element_t<Is, EvTplT>>.emplace(this, func), ...);
 
         (_moveFunc.emplace_back([](MccFiniteStateMachine* from, MccFiniteStateMachine* to) {
             _dispatchEventFunc<std::tuple_element_t<Is, EvTplT>>[to] =
@@ -451,9 +451,9 @@ public:
 
         using all_events_t = deduce_events_t<InitStateT>;
 
-        // for_each_event<all_events_t>([this]<traits::fsm_event_c EvT>(EvT) { _eventID.emplace_back(EvT::ID); });
-
         /*
+        for_each_event<all_events_t>([this]<traits::fsm_event_c EvT>(EvT) { _eventID.emplace_back(EvT::ID); });
+
         for_each_event<all_events_t>([states, currentState, this]<traits::fsm_event_c EvT>(EvT) mutable {
             if constexpr (!in_tuple_v<EvT, all_events_t>) {
                 throw std::system_error(MccFiniteStateMachineErrorCode::ERROR_UNREGISTERED_EVENT_TYPE);
@@ -515,7 +515,8 @@ public:
                 _dispatchEventFunc<EvT>.erase(inst);
             });
         });
-        */
+
+
 
         setupInstanceFuncs<all_events_t>([states, currentState, this]<traits::fsm_event_c EvT>(EvT& event) mutable {
             std::lock_guard lock(_transitionMutex);
@@ -561,6 +562,76 @@ public:
                 },
                 *currentState);
         });
+        */
+
+        [states, currentState, this]<size_t... Is>(std::index_sequence<Is...>) {
+            ((_dispatchEventFunc<std::tuple_element_t<Is, all_events_t>>[this] =
+                  [states, currentState, this]<traits::fsm_event_c EvT>(EvT& event) mutable {
+                      std::lock_guard lock(_transitionMutex);
+
+                      std::visit(
+                          [&event, states, currentState, this]<traits::fsm_state_c curr_state_t>(curr_state_t*) {
+                              using to_state_t = curr_state_t::transition_t::template find_state_by_event_t<EvT>;
+                              if constexpr (!std::is_void_v<to_state_t>) {
+                                  // exit from current
+                                  if constexpr (requires(curr_state_t inst) {
+                                                    { inst.exit(std::declval<EvT&>()) };
+                                                }) {
+                                      std::get<curr_state_t>(*states).exit(event);
+                                  } else if constexpr (requires(curr_state_t inst) {
+                                                           { inst.exit() };
+                                                       }) {
+                                      std::get<curr_state_t>(*states).exit();
+                                  }
+
+                                  // transit ...
+                                  if constexpr (requires(EvT inst) {
+                                                    { inst.onTransit() };
+                                                }) {
+                                      event.onTransit();
+                                  }
+
+                                  *currentState = &std::get<to_state_t>(*states);
+                                  _currentStateID = to_state_t::ID;
+
+                                  // enter to new
+                                  if constexpr (requires(to_state_t inst) {
+                                                    { inst.enter(std::declval<EvT&>()) };
+                                                }) {
+                                      std::get<to_state_t>(*states).enter(event);
+                                  } else if constexpr (requires(to_state_t inst) {
+                                                           { inst.enter() };
+                                                       }) {
+                                      std::get<to_state_t>(*states).enter();
+                                  }
+                              } else {
+                                  throw std::system_error(MccFiniteStateMachineErrorCode::ERROR_UNHANDLED_TRANSITION);
+                              }
+                          },
+                          *currentState);
+                  }),
+             ...);
+
+            (_moveFunc.emplace_back([](MccFiniteStateMachine* from, MccFiniteStateMachine* to) {
+                _dispatchEventFunc<std::tuple_element_t<Is, all_events_t>>[to] =
+                    std::move(_dispatchEventFunc<std::tuple_element_t<Is, all_events_t>>[from]);
+            }),
+             ...);
+
+            (_copyFunc.emplace_back([](const MccFiniteStateMachine* from, MccFiniteStateMachine* to) {
+                _dispatchEventFunc<std::tuple_element_t<Is, all_events_t>>[to] =
+                    _dispatchEventFunc<std::tuple_element_t<Is, all_events_t>>[from];
+            }),
+             ...);
+
+            (_destroyFunc.emplace_back([](const MccFiniteStateMachine* inst) {
+                //
+                _dispatchEventFunc<std::tuple_element_t<Is, all_events_t>>.erase(inst);
+            }),
+             ...);
+
+            (_eventID.emplace_back(std::tuple_element_t<Is, all_events_t>::ID), ...);
+        }(std::make_index_sequence<std::tuple_size_v<all_events_t>>());
 
         std::cout << "MOVE VEC: " << _moveFunc.size() << "\n";
     }
@@ -595,6 +666,10 @@ public:
     template <traits::fsm_event_c EvT>
     auto dispatchEvent(EvT& event)
     {
+        if (!_dispatchEventFunc<EvT>[this]) {
+            throw std::system_error(MccFiniteStateMachineErrorCode::ERROR_UNREGISTERED_EVENT_TYPE);
+        }
+
         _dispatchEventFunc<EvT>[this](event);
     }
 
diff --git a/cxx/tests/fsm_test.cpp b/cxx/tests/fsm_test.cpp
index e54c8fa..37c1444 100644
--- a/cxx/tests/fsm_test.cpp
+++ b/cxx/tests/fsm_test.cpp
@@ -30,27 +30,56 @@ struct EV3 {
     static constexpr std::string_view ID = "EV3";
 };
 
+struct EVN {
+    static constexpr std::string_view ID = "EVN";
+};
+
 struct ST1;
 struct ST2;
 
 struct STN {
     static constexpr std::string_view ID = "STN";
     using transition_t = fsm::fsm_transition_table_t<std::pair<EV1, STN>, std::pair<EV2, ST2>>;
+
+    void enter()
+    {
+        std::cout << "transit to " << ID << "-state\n";
+    }
+
+    void exit()
+    {
+        std::cout << "transit from " << ID << "-state\n";
+    }
 };
 
 struct ST3 {
     static constexpr std::string_view ID = "ST3";
     using transition_t = fsm::fsm_transition_table_t<std::pair<EV1, ST1>, std::pair<EV2, ST2>>;
+
+    void enter(EV3& ev)
+    {
+        std::cout << "transit to " << ID << "-state\n";
+    }
+
+    void exit()
+    {
+        std::cout << "transit from " << ID << "-state\n";
+    }
 };
 
 struct ST2 {
     static constexpr std::string_view ID = "ST2";
     using transition_t = fsm::fsm_transition_table_t<std::pair<EV2, STN>, std::pair<EV3, ST3>>;
 
-    void enter(EV1& ev)
+    void enter(EV2& ev)
     {
         std::cout << "transit to " << ID << "-state\n";
     }
+
+    void exit()
+    {
+        std::cout << "transit from " << ID << "-state\n";
+    }
 };
 
 struct ST1 {
@@ -58,6 +87,11 @@ struct ST1 {
     using transition_t =
         fsm::fsm_transition_table_t<std::pair<EV1, ST2>, std::pair<EV2, STN>, std::pair<EV3, STN>, std::pair<EV3, STN>>;
 
+    void enter()
+    {
+        std::cout << "transit to " << ID << "-state\n";
+    }
+
     void exit()
     {
         std::cout << "transit from " << ID << "-state\n";
@@ -151,8 +185,10 @@ int main()
     std::cout << "\n";
 
     fsmach.dispatchEvent<EV1>();
-    // fsmach.dispatchEvent<EV1>();
+    fsmach.dispatchEvent<EV3>();
+    fsmach.dispatchEvent<EV2>();
 
+    // fsmach.dispatchEvent<EVN>();
 
     // using tab_t = fsm::fsm_transition_table_t<std::pair<EV1, ST2>, std::pair<EV3, ST1>>;