---
source: framec/tests/cpp_snapshots.rs
expression: "compile_fixture(\"05_pushpop\", \"cpp\")"
---
#include <string>
#include <unordered_map>
#include <vector>
#include <any>
#include <memory>
#include <functional>

class PushPopFrameEvent {
public:
    std::string _message;
    std::vector<std::any> _parameters;

    PushPopFrameEvent(const std::string& message, std::vector<std::any> params = {})
        : _message(message), _parameters(std::move(params)) {}
};

class PushPopFrameContext {
public:
    PushPopFrameEvent _event;
    std::any _return;
    std::unordered_map<std::string, std::any> _data;
    bool _transitioned = false;

    PushPopFrameContext(PushPopFrameEvent event, std::any default_return = {})
        : _event(std::move(event)), _return(std::move(default_return)) {}
};

class PushPopCompartment {
public:
    std::string state;
    std::vector<std::any> state_args;
    std::unordered_map<std::string, std::any> state_vars;
    std::vector<std::any> enter_args;
    std::vector<std::any> exit_args;
    std::unique_ptr<PushPopFrameEvent> forward_event;
    std::shared_ptr<PushPopCompartment> parent_compartment;

    explicit PushPopCompartment(const std::string& state) : state(state) {}
};

class PushPop {
private:
    std::vector<std::shared_ptr<PushPopCompartment>> _state_stack;
    std::shared_ptr<PushPopCompartment> __compartment;
    std::shared_ptr<PushPopCompartment> __next_compartment;
    std::vector<PushPopFrameContext> _context_stack;

    std::shared_ptr<PushPopCompartment> __prepareEnter(const std::string& leaf, std::vector<std::any> state_args, std::vector<std::any> enter_args) {
        std::shared_ptr<PushPopCompartment> comp = nullptr;
        auto chain_table = hsm_chain();
        for (const auto& name : chain_table[leaf]) {
            auto new_comp = std::make_shared<PushPopCompartment>(name);
            new_comp->state_args = state_args;
            new_comp->enter_args = enter_args;
            new_comp->parent_compartment = comp;
            comp = new_comp;
        }
        return comp;

    }

    void __prepareExit(std::vector<std::any> exit_args) {
        std::shared_ptr<PushPopCompartment> comp = __compartment;
        while (comp) {
            comp->exit_args = exit_args;
            comp = comp->parent_compartment;
        }

    }

    void __kernel(PushPopFrameEvent& __e) {
        // Route event to current state.
        __router(__e);
        // Drain any transitions queued by the handler.
        while (__next_compartment) {
            auto next_compartment = std::move(__next_compartment);
            // Exit the current (leaf) state.
            PushPopFrameEvent __exit_event("<$", __compartment->exit_args);
            __router(__exit_event);
            // Switch to the new compartment.
            __compartment = std::move(next_compartment);
            // Three-branch forward-event handling.
            if (!__compartment->forward_event) {
                // No forwarded event — synthesize a fresh $>.
                PushPopFrameEvent __enter_event("$>", __compartment->enter_args);
                __router(__enter_event);
            } else if (__compartment->forward_event->_message == "$>") {
                // Forwarded event IS $> — dispatch directly so the
                // destination's $> handler receives the caller's payload.
                auto forward_event = std::move(__compartment->forward_event);
                __router(*forward_event);
            } else {
                // Forwarded event is not $> — initialize the destination
                // with a fresh $>, then dispatch the forward.
                auto forward_event = std::move(__compartment->forward_event);
                PushPopFrameEvent __enter_event("$>", __compartment->enter_args);
                __router(__enter_event);
                __router(*forward_event);
            }
            for (auto& ctx : _context_stack) {
                ctx._transitioned = true;
            }
        }

    }

    void __router(PushPopFrameEvent& __e) {
        if (__compartment->state == "Idle") {
            _state_Idle(__e, __compartment);
        } else if (__compartment->state == "Nested") {
            _state_Nested(__e, __compartment);
        }

    }

    void __transition(std::shared_ptr<PushPopCompartment> next) {
        __next_compartment = next;

    }

    void _state_Idle(PushPopFrameEvent& __e, std::shared_ptr<PushPopCompartment> compartment) {
        if (__e._message == "nest") {
            this->_s_Idle_hdl_user_nest(__e, compartment);
            return;
        }
        if (__e._message == "ping") {
            this->_s_Idle_hdl_user_ping(__e, compartment);
            return;
        }

    }

    void _state_Nested(PushPopFrameEvent& __e, std::shared_ptr<PushPopCompartment> compartment) {
        if (__e._message == "leaf") {
            this->_s_Nested_hdl_user_leaf(__e, compartment);
            return;
        }
        if (__e._message == "unnest") {
            this->_s_Nested_hdl_user_unnest(__e, compartment);
            return;
        }

    }

    void _s_Idle_hdl_user_nest(PushPopFrameEvent& __e, std::shared_ptr<PushPopCompartment> compartment) {
        _state_stack.push_back(__compartment);
        auto __next = __prepareEnter("Nested", std::vector<std::any>{}, std::vector<std::any>{});
        __transition(std::move(__next));
        return;

    }

    void _s_Idle_hdl_user_ping(PushPopFrameEvent& __e, std::shared_ptr<PushPopCompartment> compartment) {
        self.pings = self.pings + 1

    }

    void _s_Nested_hdl_user_leaf(PushPopFrameEvent& __e, std::shared_ptr<PushPopCompartment> compartment) {
        self.leaves = self.leaves + 1

    }

    void _s_Nested_hdl_user_unnest(PushPopFrameEvent& __e, std::shared_ptr<PushPopCompartment> compartment) {
        auto __saved = std::move(_state_stack.back()); _state_stack.pop_back();
        __transition(std::move(__saved));
        return;

    }

public:
    i32 pings = 0;
    i32 leaves = 0;

    PushPop() {
        __compartment = __prepareEnter("Idle", std::vector<std::any>{}, std::vector<std::any>{});
    }

    static PushPop __create() {
        PushPop c;
        PushPopFrameEvent __e("$>", c.__compartment->enter_args);
        PushPopFrameContext __ctx(std::move(__e));
        c._context_stack.push_back(std::move(__ctx));
        c.__kernel(c._context_stack.back()._event);
        c._context_stack.pop_back();
        return c;
    }

    std::unordered_map<std::string, std::vector<std::string>> hsm_chain() {
        return {
            {"Idle", {"Idle"} },
            {"Nested", {"Nested"} },
        };
    }

    void ping() {
        PushPopFrameEvent __e("ping");
        PushPopFrameContext __ctx(std::move(__e));
        _context_stack.push_back(std::move(__ctx));
        __kernel(_context_stack.back()._event);
        _context_stack.pop_back();

    }

    void nest() {
        PushPopFrameEvent __e("nest");
        PushPopFrameContext __ctx(std::move(__e));
        _context_stack.push_back(std::move(__ctx));
        __kernel(_context_stack.back()._event);
        _context_stack.pop_back();

    }

    void unnest() {
        PushPopFrameEvent __e("unnest");
        PushPopFrameContext __ctx(std::move(__e));
        _context_stack.push_back(std::move(__ctx));
        __kernel(_context_stack.back()._event);
        _context_stack.pop_back();

    }

    void leaf() {
        PushPopFrameEvent __e("leaf");
        PushPopFrameContext __ctx(std::move(__e));
        _context_stack.push_back(std::move(__ctx));
        __kernel(_context_stack.back()._event);
        _context_stack.pop_back();

    }
};
