1 #ifndef MSP_GAME_REFLECTION_H_
2 #define MSP_GAME_REFLECTION_H_
11 namespace Reflection {
16 class PolymorphismBase
19 virtual ~PolymorphismBase() = default;
21 virtual bool is_instance_of(const void *, const PolymorphismBase &) const = 0;
26 class RootedPolymorphism: public PolymorphismBase
29 virtual bool is_instance(const B &) const = 0;
33 template<typename T, typename B>
34 requires std::is_base_of_v<B, T>
35 class Polymorphism: public RootedPolymorphism<B>
38 bool is_instance(const B &obj) const override { return std::is_same_v<B, T> || dynamic_cast<const T *>(&obj); }
39 bool is_instance_of(const void *, const PolymorphismBase &) const override;
49 std::vector<const ClassBase *> bases;
50 std::unique_ptr<PolymorphismBase> polymorphism;
52 ClassBase(Reflector &, std::type_index);
54 virtual ~ClassBase() = default;
56 const std::type_index &get_type() const { return type; }
57 const std::string &get_name() const { return name; }
59 bool is_direct_base_of(const ClassBase &) const;
60 bool is_base_of(const ClassBase &) const;
63 bool is_instance(const T &) const;
66 bool has_polymorphic_base() const { return dynamic_cast<const RootedPolymorphism<T> *>(polymorphism.get()); }
71 class Class: public ClassBase
74 Class(Reflector &r): ClassBase(r, typeid(T)) { }
77 void set_polymorphic_base();
80 void set_polymorphic_base(const T &obj) { set_polymorphic_base<B>(); check_bases<B>(obj); }
84 void check_bases(const T &obj);
91 std::vector<std::unique_ptr<ClassBase>> classes;
93 std::vector<std::unique_ptr<ClassBase>>::const_iterator lower_bound(const std::type_index &) const;
96 ClassBase *find_class(const std::type_index &) const;
99 Class<T> *find_class() const { return static_cast<Class<T> *>(find_class(typeid(T))); }
102 Class<T> &get_or_create_class();
105 std::vector<ClassBase *> find_classes_if(F &&) const;
109 inline std::vector<std::unique_ptr<ClassBase>>::const_iterator Reflector::lower_bound(const std::type_index &type) const
111 return std::ranges::lower_bound(classes, type, {}, [](auto &c){ return c->get_type(); });
115 inline Class<T> &Reflector::get_or_create_class()
117 std::type_index type = typeid(T);
118 auto i = lower_bound(type);
119 if(i==classes.end() || (*i)->get_type()!=type)
120 i = classes.emplace(i, std::make_unique<Class<T>>(std::ref(*this)));
121 return static_cast<Class<T> &>(*i->get());
125 inline std::vector<ClassBase *> Reflector::find_classes_if(F &&pred) const
127 std::vector<ClassBase *> result;
128 for(auto &c: classes)
130 result.push_back(&*c);
135 template<typename T, typename B>
136 inline bool Polymorphism<T, B>::is_instance_of(const void *obj, const PolymorphismBase &other) const
138 if(const RootedPolymorphism<B> *rooted = dynamic_cast<const RootedPolymorphism<B> *>(&other))
139 return rooted->is_instance(*static_cast<const T *>(obj));
145 inline bool ClassBase::is_instance(const T &obj) const
147 if(const RootedPolymorphism<T> *p = dynamic_cast<const RootedPolymorphism<T> *>(polymorphism.get()))
148 return p->is_instance(obj);
149 else if(ClassBase *c = reflector.find_class<T>(); c->polymorphism)
150 return c->polymorphism->is_instance_of(&obj, *polymorphism);
157 inline void Class<T>::set_polymorphic_base()
160 polymorphism = std::make_unique<Polymorphism<T, B>>();
161 else if(!dynamic_cast<const Polymorphism<T, B> *>(polymorphism.get()))
162 throw std::logic_error("conflicting polymorphism");
167 inline void Class<T>::check_bases(const T &obj)
169 std::vector<const ClassBase *> candidate_bases;
170 for(const ClassBase *b: reflector.find_classes_if([](const ClassBase &c){ return c.has_polymorphic_base<B>(); }))
171 if(b!=this && b->is_instance<B>(obj))
172 candidate_bases.push_back(b);
174 for(auto i=candidate_bases.begin(); i!=candidate_bases.end(); )
176 if(std::ranges::any_of(candidate_bases, [i](const ClassBase *c){ return (c!=*i && (*i)->is_direct_base_of(*c)); }))
177 i = candidate_bases.erase(i);
182 bases = std::move(candidate_bases);
185 } // namespace Reflection
186 } // namespace Msp::Game