dev/table_name_collector.h - master - UCS/sqlite_orm

dev/table_name_collector.h
94 строки3 KB
klaus triendl
Applied new code formatting
16 янв 2023, 12:17
16 янв 2023, 12:175818dac
#pragma once

#include <set>  //  std::set
#include <string>  //  std::string
#include <functional>  //  std::function
#include <typeindex>  //  std::type_index

#include "functional/cxx_type_traits_polyfill.h"
#include "type_traits.h"
#include "select_constraints.h"
#include "alias.h"
#include "core_functions.h"

namespace sqlite_orm {

    namespace internal {

        struct table_name_collector {
            using table_name_set = std::set<std::pair<std::string, std::string>>;
            using find_table_name_t = std::function<std::string(const std::type_index&)>;

            find_table_name_t find_table_name;
            mutable table_name_set table_names;

            table_name_collector() = default;

            table_name_collector(find_table_name_t find_table_name) : find_table_name{move(find_table_name)} {}

            template<class T>
            table_name_set operator()(const T&) const {
                return {};
            }

            template<class F, class O>
            void operator()(F O::*, std::string alias = {}) const {
                table_names.emplace(this->find_table_name(typeid(O)), move(alias));
            }

            template<class T, class F>
            void operator()(const column_pointer<T, F>&) const {
                table_names.emplace(this->find_table_name(typeid(T)), "");
            }

            template<class T, class C>
            void operator()(const alias_column_t<T, C>& a) const {
                (*this)(a.column, alias_extractor<T>::get());
            }

            template<class T>
            void operator()(const count_asterisk_t<T>&) const {
                auto tableName = this->find_table_name(typeid(T));
                if(!tableName.empty()) {
                    table_names.emplace(move(tableName), "");
                }
            }

            template<class T, satisfies_not<std::is_base_of, alias_tag, T> = true>
            void operator()(const asterisk_t<T>&) const {
                table_names.emplace(this->find_table_name(typeid(T)), "");
            }

            template<class T, satisfies<std::is_base_of, alias_tag, T> = true>
            void operator()(const asterisk_t<T>&) const {
                // note: not all alias classes have a nested A::type
                static_assert(polyfill::is_detected_v<type_t, T>,
                              "alias<O> must have a nested alias<O>::type typename");
                auto tableName = this->find_table_name(typeid(type_t<T>));
                table_names.emplace(move(tableName), alias_extractor<T>::get());
            }

            template<class T>
            void operator()(const object_t<T>&) const {
                table_names.emplace(this->find_table_name(typeid(T)), "");
            }

            template<class T>
            void operator()(const table_rowid_t<T>&) const {
                table_names.emplace(this->find_table_name(typeid(T)), "");
            }

            template<class T>
            void operator()(const table_oid_t<T>&) const {
                table_names.emplace(this->find_table_name(typeid(T)), "");
            }

            template<class T>
            void operator()(const table__rowid_t<T>&) const {
                table_names.emplace(this->find_table_name(typeid(T)), "");
            }
        };

    }

}