state_builder.hpp

//Copyright Florian Goujeon 2021 - 2025.
//Distributed under the Boost Software License, Version 1.0.
//(See accompanying file LICENSE or copy at
//https://www.boost.org/LICENSE_1_0.txt)
//Official repository: https://github.com/fgoujeon/maki

 
#ifndef MAKI_STATE_BUILDER_HPP
#define MAKI_STATE_BUILDER_HPP
 
#include "action.hpp"
#include "context.hpp"
#include "event_set.hpp"
#include "detail/state_builder_fwd.hpp"
#include "detail/type.hpp"
#include "detail/event_action.hpp"
#include "detail/signature_macros.hpp"
#include "detail/tuple.hpp"
#include "detail/impl.hpp"
#include "detail/tlu.hpp"
#include <string_view>
#include <type_traits>
 
namespace maki
{
 
#ifdef MAKI_DETAIL_DOXYGEN
#define MAKI_DETAIL_STATE_CONF_RETURN_TYPE state_builder<IMPLEMENTATION_DETAIL>
#else
#define MAKI_DETAIL_STATE_CONF_RETURN_TYPE auto
#endif

template<class Impl>
class state_builder
{
public:
    using context_type = typename Impl::context_type;
 
    constexpr state_builder() = default;
 
    state_builder(const state_builder&) = delete;
 
    state_builder(state_builder&&) = delete;
 
    ~state_builder() = default;
 
    state_builder& operator=(const state_builder&) = delete;
 
    state_builder& operator=(state_builder&&) = delete;
 
#define MAKI_DETAIL_MAKE_STATE_CONF_COPY_BEGIN /*NOLINT(cppcoreguidelines-macro-usage)*/ \
    [[maybe_unused]] const auto MAKI_DETAIL_ARG_context_type = detail::type<typename Impl::context_type>; \
    [[maybe_unused]] const auto MAKI_DETAIL_ARG_context_sig = impl_.context_sig; \
    [[maybe_unused]] const auto MAKI_DETAIL_ARG_entry_actions = impl_.entry_actions; \
    [[maybe_unused]] const auto MAKI_DETAIL_ARG_internal_actions = impl_.internal_actions; \
    [[maybe_unused]] const auto MAKI_DETAIL_ARG_exit_actions = impl_.exit_actions; \
    [[maybe_unused]] const auto MAKI_DETAIL_ARG_pretty_name_view = impl_.pretty_name; \
    [[maybe_unused]] const auto MAKI_DETAIL_ARG_transition_tables = impl_.transition_tables;
 
#define MAKI_DETAIL_MAKE_STATE_CONF_COPY_END /*NOLINT(cppcoreguidelines-macro-usage)*/ \
    return state_builder \
    < \
        detail::state_builder_option_set \
        < \
            typename std::decay_t<decltype(MAKI_DETAIL_ARG_context_type)>::type, \
            std::decay_t<decltype(MAKI_DETAIL_ARG_entry_actions)>, \
            std::decay_t<decltype(MAKI_DETAIL_ARG_internal_actions)>, \
            std::decay_t<decltype(MAKI_DETAIL_ARG_exit_actions)>, \
            std::decay_t<decltype(MAKI_DETAIL_ARG_transition_tables)> \
        > \
    > \
    { \
        MAKI_DETAIL_ARG_context_sig, \
        MAKI_DETAIL_ARG_entry_actions, \
        MAKI_DETAIL_ARG_internal_actions, \
        MAKI_DETAIL_ARG_exit_actions, \
        MAKI_DETAIL_ARG_pretty_name_view, \
        MAKI_DETAIL_ARG_transition_tables \
    };
 
#define MAKI_DETAIL_X(signature) /*NOLINT(cppcoreguidelines-macro-usage)*/ \
 \
    template<class Context> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE context_##signature() const \
    { \
        return context<Context, state_context_signature::signature>(); \
    }
    MAKI_DETAIL_STATE_CONTEXT_CONSTRUCTOR_SIGNATURES
#undef MAKI_DETAIL_X
 
#define MAKI_DETAIL_X(signature) /*NOLINT(cppcoreguidelines-macro-usage)*/ \
 \
    template<class EventSetPredicate, class Action> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE entry_action_##signature(const event_set<EventSetPredicate>& evt_set, const Action& action) const \
    { \
        return entry_action<action_signature::signature>(evt_set, action); \
    } \
 \
 \
    template<class Event, class Action> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE entry_action_##signature(const Action& action) const \
    { \
        return entry_action_##signature(event_set{event<Event>}, action); \
    } \
 \
 \
    template<class Action> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE entry_action_##signature(const Action& action) const \
    { \
        return entry_action_##signature(all_events, action); \
    }
    MAKI_DETAIL_ACTION_SIGNATURES
#undef MAKI_DETAIL_X
 
#define MAKI_DETAIL_X(signature) /*NOLINT(cppcoreguidelines-macro-usage)*/ \
    MAKI_DETAIL_ACTION_SIGNATURES
#undef MAKI_DETAIL_X
 
#define MAKI_DETAIL_X(signature) /*NOLINT(cppcoreguidelines-macro-usage)*/ \
 \
    template<class EventSetPredicate, class Action> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE internal_action_##signature(const event_set<EventSetPredicate>& evt_set, const Action& action) const \
    { \
        return internal_action<action_signature::signature>(evt_set, action); \
    } \
 \
 \
    template<class Event, class Action> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE internal_action_##signature(const Action& action) const \
    { \
        return internal_action_##signature(event_set{event<Event>}, action); \
    }
    MAKI_DETAIL_ACTION_SIGNATURES
#undef MAKI_DETAIL_X
 
#define MAKI_DETAIL_X(signature) /*NOLINT(cppcoreguidelines-macro-usage)*/ \
 \
    template<class EventSetPredicate, class Action> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE exit_action_##signature(const event_set<EventSetPredicate>& evt_set, const Action& action) const \
    { \
        return exit_action<action_signature::signature>(evt_set, action); \
    } \
 \
 \
    template<class Event, class Action> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE exit_action_##signature(const Action& action) const \
    { \
        return exit_action_##signature(event_set{event<Event>}, action); \
    } \
 \

    to be called whatever the event type. \
    */ \
    template<class Action> \
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE exit_action_##signature(const Action& action) const \
    { \
        return exit_action_##signature(all_events, action); \
    }
    MAKI_DETAIL_ACTION_SIGNATURES
#undef MAKI_DETAIL_X

    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE pretty_name(const std::string_view value) const
    {
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_BEGIN
#define MAKI_DETAIL_ARG_pretty_name_view value
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_END
#undef MAKI_DETAIL_ARG_pretty_name_view
    }

    template<class... TransitionTables>
    [[nodiscard]] constexpr MAKI_DETAIL_STATE_CONF_RETURN_TYPE transition_tables(const TransitionTables&... tables) const
    {
        const auto tpl = detail::tuple<TransitionTables...>{detail::distributed_construct, tables...};
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_BEGIN
#define MAKI_DETAIL_ARG_transition_tables tpl
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_END
#undef MAKI_DETAIL_ARG_transition_tables
    }
 
private:
    using impl_type = Impl;
 
    template<class Impl2>
    friend class state_builder;
 
    template<class... Args>
    constexpr state_builder(Args&&... args):
        impl_{std::forward<Args>(args)...}
    {
    }
 
    template<class Context, auto ContextSig>
    [[nodiscard]] constexpr auto context() const
    {
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_BEGIN
#define MAKI_DETAIL_ARG_context_type detail::type<Context>
#define MAKI_DETAIL_ARG_context_sig ContextSig
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_END
#undef MAKI_DETAIL_ARG_context_type
#undef MAKI_DETAIL_ARG_context_sig
    }
 
    template<action_signature Sig, class EventSetPredicate, class Action>
    [[nodiscard]] constexpr auto entry_action(const event_set<EventSetPredicate>& evt_set, const Action& action) const
    {
        const auto new_entry_actions = tuple_append
        (
            impl_.entry_actions,
            detail::make_event_action<Sig>(evt_set, action)
        );
 
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_BEGIN
#define MAKI_DETAIL_ARG_entry_actions new_entry_actions
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_END
#undef MAKI_DETAIL_ARG_entry_actions
    }
 
    template<action_signature Sig, class EventSetPredicate, class Action>
    [[nodiscard]] constexpr auto internal_action(const event_set<EventSetPredicate>& evt_set, const Action& action) const
    {
        const auto new_internal_actions = tuple_append
        (
            impl_.internal_actions,
            detail::make_event_action<Sig>(evt_set, action)
        );
 
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_BEGIN
#define MAKI_DETAIL_ARG_internal_actions new_internal_actions
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_END
#undef MAKI_DETAIL_ARG_internal_actions
    }
 
    template<action_signature Sig, class EventSetPredicate, class Action>
    [[nodiscard]] constexpr auto exit_action(const event_set<EventSetPredicate>& evt_set, const Action& action) const
    {
        const auto new_exit_actions = tuple_append
        (
            impl_.exit_actions,
            detail::make_event_action<Sig>(evt_set, action)
        );
 
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_BEGIN
#define MAKI_DETAIL_ARG_exit_actions new_exit_actions
        MAKI_DETAIL_MAKE_STATE_CONF_COPY_END
#undef MAKI_DETAIL_ARG_exit_actions
    }
 
#undef MAKI_DETAIL_MAKE_STATE_CONF_COPY_END
#undef MAKI_DETAIL_MAKE_STATE_CONF_COPY_BEGIN
 
    MAKI_DETAIL_FRIENDLY_IMPL
};
 
#undef MAKI_DETAIL_STATE_CONF_RETURN_TYPE
 
} //namespace
 
#endif