
.. _program_listing_file_cif++_row.hpp:

Program Listing for File row.hpp
================================

|exhale_lsh| :ref:`Return to documentation for file <file_cif++_row.hpp>` (``cif++/row.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   /*-
    * SPDX-License-Identifier: BSD-2-Clause
    *
    * Copyright (c) 2022 NKI/AVL, Netherlands Cancer Institute
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions are met:
    *
    * 1. Redistributions of source code must retain the above copyright notice, this
    *    list of conditions and the following disclaimer
    * 2. Redistributions in binary form must reproduce the above copyright notice,
    *    this list of conditions and the following disclaimer in the documentation
    *    and/or other materials provided with the distribution.
    *
    * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
    * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
    * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
    * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    */
   
   #pragma once
   
   #include "cif++/item.hpp"
   
   #include <array>
   #include <cstddef>
   #include <cstdint>
   #include <initializer_list>
   #include <string>
   #include <string_view>
   #include <tuple>
   #include <type_traits>
   #include <utility>
   #include <vector>
   
   
   namespace cif
   {
   
   class category;
   
   namespace cql
   {
       struct connection_impl;
   }
   
   namespace detail
   {
       template <typename... C>
       struct get_row_result;
   }
   
   // --------------------------------------------------------------------
   
   class row : public std::vector<item_value>
   {
     public:
       row() = default;
   
     private:
       item_value *get(uint16_t ix)
       {
           if (ix >= size())
               resize(ix + 1);
           return &data()[ix];
       }
   
       [[nodiscard]] const item_value *get(uint16_t ix) const
       {
           return ix < size() ? &data()[ix] : nullptr;
       }
   
       void set(uint16_t ix, item_value v)
       {
           if (ix >= size())
               resize(ix + 1);
           operator[](ix) = std::move(v);
       }
   
       friend class category;
       friend class category_index;
   
       template <bool, typename...>
       friend class iterator_impl_base;
   
       row *m_next = nullptr;
   };
   
   // --------------------------------------------------------------------
   
   class row_handle
   {
     public:
       template <bool>
       friend struct item_handle_base;
       friend class category;
       friend class category_index;
       friend class row_initializer;
       friend class const_row_handle;
   
       template <bool, typename...>
       friend class iterator_impl_base;
   
       row_handle() = default;
       virtual ~row_handle() = default;
   
       row_handle(const row_handle &) = default;
       row_handle(row_handle &&) = default;
       row_handle &operator=(const row_handle &) = default;
       row_handle &operator=(row_handle &&) = default;
   
   
       row_handle(category &cat, row &r)
           : m_category(&cat)
           , m_row(&r)
       {
       }
   
       [[nodiscard]] category &get_category() const
       {
           return *m_category;
       }
   
       [[nodiscard]] int64_t row_id() const
       {
           return reinterpret_cast<int64_t>(m_row);
       }
   
       [[nodiscard]] bool empty() const
       {
           return m_category == nullptr or m_row == nullptr;
       }
   
       explicit operator bool() const
       {
           return not empty();
       }
   
       [[nodiscard]] size_t size() const { return m_row->size(); }
   
       item_handle operator[](uint16_t item_ix)
       {
           return { *m_category, *m_row, item_ix };
       }
   
       const item_handle operator[](uint16_t item_ix) const
       {
           return { *m_category, *m_row, item_ix };
       }
   
       item_handle operator[](std::string_view item_name)
       {
           return { *m_category, *m_row, add_item(item_name) };
       }
   
       const item_handle operator[](std::string_view item_name) const
       {
           return { *m_category, *m_row, get_item_ix(item_name) };
       }
   
       void assign(const std::vector<item> &values, bool updateLinked = true)
       {
           for (auto &value : values)
               assign(value, updateLinked);
       }
   
   
       void assign(std::string_view name, item_value value, bool updateLinked, bool validate = true)
       {
           assign(add_item(name), std::move(value), updateLinked, validate);
       }
   
   
       void assign(uint16_t item, item_value value, bool updateLinked, bool validate = true);
   
       template <typename... C>
       [[nodiscard]] auto get(C... items) const
       {
           return detail::get_row_result<C...>(*this, { get_item_ix(items)... });
       }
   
       template <typename... Ts, typename... C>
       std::tuple<Ts...> get(C... items) const
           requires(sizeof...(Ts) == sizeof...(C) and sizeof...(C) != 1)
       {
           return detail::get_row_result<Ts...>(*this, { get_item_ix(items)... });
       }
   
       template <typename T>
       [[nodiscard]] T get(std::string_view item) const
       {
           return operator[](get_item_ix(item)).template get<T>();
       }
   
       bool operator==(const row_handle &rhs) const { return m_category == rhs.m_category and m_row == rhs.m_row; }
   
       bool operator!=(const row_handle &rhs) const { return m_category != rhs.m_category or m_row != rhs.m_row; }
   
     protected:
       [[nodiscard]] uint16_t get_item_ix(std::string_view name) const;
   
       [[nodiscard]] std::string_view get_item_name(uint16_t ix) const;
   
       friend cql::connection_impl;
   
       [[nodiscard]] auto get_row() const
       {
           return m_row;
       }
   
       category *m_category = nullptr; 
       row *m_row = nullptr;           
   
     private:
       uint16_t add_item(std::string_view name);
   
       void assign(const item &i, bool updateLinked)
       {
           assign(i.name(), i.value(), updateLinked);
       }
   
   };
   
   
   class const_row_handle
   {
     public:
       template <bool>
       friend struct item_handle_base;
       friend class category;
       friend class category_index;
       friend class row_initializer;
   
       template <bool, typename...>
       friend class iterator_impl_base;
   
       const_row_handle() = default;
       virtual ~const_row_handle() = default;
   
       const_row_handle(const const_row_handle &) = default;
       const_row_handle(const_row_handle &&) = default;
       const_row_handle &operator=(const const_row_handle &) = default;
       const_row_handle &operator=(const_row_handle &&) = default;
   
       const_row_handle(row_handle rh)
           : m_category(rh.m_category)
           , m_row(rh.m_row)
       {
       }
   
   
       const_row_handle(const category &cat, const row &r)
           : m_category(&cat)
           , m_row(&r)
       {
       }
   
       [[nodiscard]] const category &get_category() const
       {
           return *m_category;
       }
   
       [[nodiscard]] int64_t row_id() const
       {
           return reinterpret_cast<int64_t>(m_row);
       }
   
       [[nodiscard]] bool empty() const
       {
           return m_category == nullptr or m_row == nullptr;
       }
   
       explicit operator bool() const
       {
           return not empty();
       }
   
       [[nodiscard]] size_t size() const { return m_row->size(); }
   
       const item_handle operator[](uint16_t item_ix) const
       {
           return { *m_category, *m_row, item_ix };
       }
   
       const item_handle operator[](std::string_view item_name) const
       {
           return operator[](get_item_ix(item_name));
       }
   
       template <typename... C>
       [[nodiscard]] auto get(C... items) const
       {
           return detail::get_row_result<C...>(*this, { get_item_ix(items)... });
       }
   
       template <typename... Ts, typename... C>
       std::tuple<Ts...> get(C... items) const
           requires(sizeof...(Ts) == sizeof...(C) and sizeof...(C) != 1)
       {
           return detail::get_row_result<Ts...>(*this, { get_item_ix(items)... });
       }
   
       template <typename T>
       [[nodiscard]] T get(std::string_view item) const
       {
           return operator[](get_item_ix(item)).template get<T>();
       }
   
       // bool operator==(const const_row_handle &rhs) const { return m_category == rhs.m_category and m_row == rhs.m_row; }
       friend bool operator==(const_row_handle a, const_row_handle b)
       {
           return a.m_category == b.m_category and a.m_row == b.m_row;
       }
   
       bool operator!=(const const_row_handle &rhs) const { return m_category != rhs.m_category or m_row != rhs.m_row; }
   
     protected:
       [[nodiscard]] uint16_t get_item_ix(std::string_view name) const;
   
       [[nodiscard]] std::string_view get_item_name(uint16_t ix) const;
   
       friend cql::connection_impl;
   
       [[nodiscard]] auto get_row() const
       {
           return m_row;
       }
   
       const category *m_category = nullptr; 
       const row *m_row = nullptr;           
   };
   
   namespace detail
   {
   
       template <typename... C>
       struct get_row_result
       {
           static constexpr std::size_t N = sizeof...(C);
   
           get_row_result(const_row_handle r, std::array<uint16_t, N> &&items)
               : m_row(std::move(r))
               , m_items(std::move(items))
           {
           }
   
           const item_handle operator[](uint16_t ix) const
           {
               return m_row[m_items[ix]];
           }
   
           template <typename... Ts>
           operator std::tuple<Ts...>() const
               requires(N == sizeof...(Ts))
           {
               return get<Ts...>(std::index_sequence_for<Ts...>{});
           }
   
           template <typename... Ts, std::size_t... Is>
           [[nodiscard]] std::tuple<Ts...> get(std::index_sequence<Is...>) const
           {
               return std::tuple<Ts...>{ m_row[m_items[Is]].template get<Ts>()... };
           }
   
           const_row_handle m_row;
           std::array<uint16_t, N> m_items;
       };
   
       // we want to be able to tie some variables to a get_row_result, for this we use tiewraps
       template <typename... Ts>
       struct tie_wrap
       {
           tie_wrap(Ts... args)
               : m_value(args...)
           {
           }
   
           template <typename RR>
           void operator=(const RR &&rr)
           {
               // get_row_result will do the conversion, but only if the types
               // are compatible. That means the number of parameters to the get()
               // of the row should be equal to the number of items in the tuple
               // you are trying to tie.
   
               using RType = std::tuple<std::remove_reference_t<Ts>...>;
   
               m_value = static_cast<RType>(rr);
           }
   
           std::tuple<Ts...> m_value;
       };
   
   
   } // namespace detail
   
   template <typename... Ts>
   auto tie(Ts &...v)
   {
       return detail::tie_wrap<Ts &...>(std::forward<Ts &>(v)...);
   }
   
   // --------------------------------------------------------------------
   
   class row_initializer : public std::vector<item>
   {
     public:
       friend class category;
   
       row_initializer() = default;
       row_initializer(const row_initializer &) = default;
       row_initializer(row_initializer &&) = default;
       row_initializer &operator=(const row_initializer &) = default;
       row_initializer &operator=(row_initializer &&) = default;
   
   
       row_initializer(std::initializer_list<item> items)
           : std::vector<item>(items)
       {
       }
   
       template <typename ItemIter>
       row_initializer(ItemIter b, ItemIter e)
           requires(std::is_constructible_v<item, typename ItemIter::value_type>)
           : std::vector<item>(b, e)
       {
       }
   
       row_initializer(row_handle rh)
           : cif::row_initializer(const_row_handle{ rh })
       {
       }
   
       row_initializer(const_row_handle rh);
   
       void set_value(std::string name, item_value value);
   
       void set_value(const item &i)
       {
           set_value(i.name(), i.value());
       }
   
       void set_value_if_empty(std::string name, item_value value);
   
       void set_value_if_empty(const item &i)
       {
           set_value_if_empty(i.name(), i.value());
       }
   
       auto emplace_back(std::string name, item_value value)
       {
           return std::vector<item>::emplace_back(item(std::forward<std::string>(name), std::forward<item_value>(value)));
       }
   };
   
   } // namespace cif
