Renderive/Core/architecture/Render_Lease.h

#pragma once
#include "Renderable.h"
#include "Strategy_Render_Data.h"
#include <utility>

namespace renderive {

template <typename Base, typename Owner, Render_State_Type State, Input_Data_Type Input>
    requires std::derived_from<Base, Render_Data>
struct Typed_Render_Data_Base : Base {
    Owner* q() {
        return reinterpret_cast<Owner*>(this->q_ptr);
    }
    State* render_state() override {
        return reinterpret_cast<State*>(this->state(Renderable_State_Role::Render));
    }
    State* ready_state() override {
        return reinterpret_cast<State*>(this->state(Renderable_State_Role::Ready));
    }
    State* edit_state() override {
        return reinterpret_cast<State*>(this->state(Renderable_State_Role::Edit));
    }
    Input* render_input_data() override {
        return reinterpret_cast<Input*>(this->input_data(Renderable_Input_Role::Render));
    }
    Input* edit_input_data() override {
        return reinterpret_cast<Input*>(this->input_data(Renderable_Input_Role::Edit));
    }
    State* render_state(const Renderable_Frame_View& frame_view) const {
        return reinterpret_cast<State*>(frame_view.state);
    }
    Input* render_input_data(const Renderable_Frame_View& frame_view) const {
        return reinterpret_cast<Input*>(frame_view.input);
    }
    State* state_data(Renderable_State_Role role) {
        return reinterpret_cast<State*>(this->state(role));
    }
    template <typename Field, typename Source_State>
        requires std::derived_from<State, Source_State>
    Field state_value(Field Source_State::* field, Renderable_State_Role role) {
        auto guard = this->acquire_state_read(role);
        if (!guard)
            return {};
        auto state = reinterpret_cast<State*>(guard.state);
        return state->*field;
    }
    template <typename Field, typename Source_State>
        requires std::derived_from<State, Source_State>
    Field edit_state_value(Field Source_State::* field) {
        return state_value(field, Renderable_State_Role::Edit);
    }
    template <typename Field, typename Source_State>
        requires std::derived_from<State, Source_State>
    Field ready_state_value(Field Source_State::* field) {
        return state_value(field, Renderable_State_Role::Ready);
    }
    template <typename Field, typename Source_State>
        requires std::derived_from<State, Source_State>
    Field render_state_value(Field Source_State::* field) {
        return state_value(field, Renderable_State_Role::Render);
    }
    template <typename Field, typename Source_State>
        requires std::derived_from<State, Source_State>
    void set_state_value(Field Source_State::* field, Field value) {
        auto guard = this->acquire_edit_state();
        if (!guard)
            return;
        auto state = reinterpret_cast<State*>(guard.state);
        state->*field = std::move(value);
    }
protected:
    void copy_render_state_object(Render_State& target, const Render_State& source) override {
        static_cast<State&>(target) = static_cast<const State&>(source);
    }
};

template <typename Owner, Render_State_Type State, Input_Data_Type Input>
using Typed_Render_Data = Typed_Render_Data_Base<Strategy_Render_Data, Owner, State, Input>;

template <typename Owner, Render_Data_Type Data, Render_State_Type State, Input_Data_Type Input>
struct Renderable_Binding {
    static void init(Owner* owner, const char* name) {
        owner->d_owner = make_render_object<Data>();
        owner->d_ptr = static_cast<Render_Data*>(owner->d_owner.template get<Data>());
        owner->set_object_name(name);
    }
    static Data* d(Owner* owner) {
        return reinterpret_cast<Data*>(owner->d_ptr);
    }
    static Render_Object_Owner create_render_data() {
        return make_render_object<Data>();
    }
    static Render_Object_Owner create_render_state() {
        return make_render_object<State>();
    }
    static Render_Object_Owner create_input_data() {
        if constexpr (std::is_same_v<Input, Input_Data>)
            return {};
        return make_render_object<Input>();
    }
};

#define RENDERIVE_DEFINE_RENDERABLE_BINDING(Owner, Data, State, Input, Name) \
    using Owner##_Binding = ::renderive::Renderable_Binding<Owner, Data, State, Input>; \
    Owner::Owner() { \
        Owner##_Binding::init(this, Name); \
    } \
    Data* Owner::d() { \
        return Owner##_Binding::d(this); \
    } \
    ::renderive::Render_Object_Owner Owner::create_render_data() { \
        return Owner##_Binding::create_render_data(); \
    } \
    ::renderive::Render_Object_Owner Owner::create_render_state() { \
        return Owner##_Binding::create_render_state(); \
    } \
    ::renderive::Render_Object_Owner Owner::create_input_data() { \
        return Owner##_Binding::create_input_data(); \
    }

template <typename Data, Render_State_Type State>
    requires std::derived_from<Data, Render_Data>
struct Render_State_Lease : Immovable {
    explicit Render_State_Lease(Data* data) : data(data) {
        guard = data->acquire_edit_state_read();
        state = reinterpret_cast<State*>(guard.state);
    }
    ~Render_State_Lease() = default;
    State* operator->() {
        return state;
    }
    State& operator*() {
        return *state;
    }
    explicit operator bool() const {
        return state && guard;
    }
    Data* data{};
    Render_State_Read_Guard guard;
    State* state{};
};

template <typename Data, Render_State_Type State>
    requires std::derived_from<Data, Render_Data>
struct Render_Edit_Lease : Immovable {
    explicit Render_Edit_Lease(Data* data) : data(data) {
        guard = data->acquire_edit_state();
        state = reinterpret_cast<State*>(guard.state);
    }
    ~Render_Edit_Lease() = default;
    State* operator->() {
        return state;
    }
    State& operator*() {
        return *state;
    }
    explicit operator bool() const {
        return state && guard;
    }
    Data* data{};
    Render_State_Write_Guard guard;
    State* state{};
};

template <typename Data, Input_Data_Type Input>
    requires std::derived_from<Data, Render_Data>
struct Render_Input_Lease : Immovable {
    explicit Render_Input_Lease(Data* data, bool notify_render = true) : data(data), notify_render(notify_render) {
        guard = data->acquire_edit_input(notify_render);
        input = reinterpret_cast<Input*>(guard.input);
    }
    ~Render_Input_Lease() = default;
    Input* operator->() {
        return input;
    }
    Input& operator*() {
        return *input;
    }
    explicit operator bool() const {
        return input && guard;
    }
    void set_completion(std::shared_ptr<Update_State> state) {
        guard.set_completion(std::move(state));
    }
    Data* data{};
    bool notify_render{};
    Render_Input_Write_Guard guard;
    Input* input{};
};

} // namespace renderive