# Program Listing for File row.hpp

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    /*-
     * 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>

    namespace cif
    {

    namespace detail
    {

        // some helper classes to help create tuple result types
        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(r)
                , m_items(std::move(items))
            {
            }

            const item_handle operator[](uint16_t ix) const
            {
                return m_row[m_items[ix]];
            }

            template <typename... Ts, std::enable_if_t<N == sizeof...(Ts), int> = 0>
            operator std::tuple<Ts...>() const
            {
                return get<Ts...>(std::index_sequence_for<Ts...>{});
            }

            template <typename... Ts, std::size_t... Is>
            std::tuple<Ts...> get(std::index_sequence<Is...>) const
            {
                return std::tuple<Ts...>{ m_row[m_items[Is]].template as<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<typename std::remove_reference<Ts>::type...>;

                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 : public std::vector<item_value>
    {
      public:
        row() = default;

        item_value* get(uint16_t ix)
        {
            return ix < size() ? &data()[ix] : nullptr;
        }

        const item_value* get(uint16_t ix) const
        {
            return ix < size() ? &data()[ix] : nullptr;
        }

      private:
        friend class category;
        friend class category_index;

        template <typename, typename...>
        friend class iterator_impl;

        void append(uint16_t ix, item_value &&iv)
        {
            if (ix >= size())
                resize(ix + 1);

            at(ix) = std::move(iv);
        }

        void remove(uint16_t ix)
        {
            if (ix < size())
                at(ix) = item_value{};
        }

        row *m_next = nullptr;
    };

    // --------------------------------------------------------------------

    class row_handle
    {
      public:
        friend struct item_handle;
        friend class category;
        friend class category_index;
        friend class row_initializer;
        template <typename, typename...> friend class iterator_impl;

        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(const category &cat, const row &r)
            : m_category(const_cast<category *>(&cat))
            , m_row(const_cast<row *>(&r))
        {
        }

        const category &get_category() const
        {
            return *m_category;
        }

        bool empty() const
        {
            return m_category == nullptr or m_row == nullptr;
        }

        explicit operator bool() const
        {
            return not empty();
        }

        item_handle operator[](uint16_t item_ix)
        {
            return empty() ? item_handle::s_null_item : item_handle(item_ix, *this);
        }

        const item_handle operator[](uint16_t item_ix) const
        {
            return empty() ? item_handle::s_null_item : item_handle(item_ix, const_cast<row_handle &>(*this));
        }

        item_handle operator[](std::string_view item_name)
        {
            return empty() ? item_handle::s_null_item : item_handle(add_item(item_name), *this);
        }

        const item_handle operator[](std::string_view item_name) const
        {
            return empty() ? item_handle::s_null_item : item_handle(get_item_ix(item_name), const_cast<row_handle &>(*this));
        }

        template <typename... C>
        auto get(C... items) const
        {
            return detail::get_row_result<C...>(*this, { get_item_ix(items)... });
        }

        template <typename... Ts, typename... C, std::enable_if_t<sizeof...(Ts) == sizeof...(C) and sizeof...(C) != 1, int> = 0>
        std::tuple<Ts...> get(C... items) const
        {
            return detail::get_row_result<Ts...>(*this, { get_item_ix(items)... });
        }

        template <typename T>
        T get(const char *item) const
        {
            return operator[](get_item_ix(item)).template as<T>();
        }

        template <typename T>
        T get(std::string_view item) const
        {
            return operator[](get_item_ix(item)).template as<T>();
        }

        void assign(const std::vector<item> &values)
        {
            for (auto &value : values)
                assign(value, true);
        }

        void assign(std::string_view name, std::string_view value, bool updateLinked, bool validate = true)
        {
            assign(add_item(name), value, updateLinked, validate);
        }

        void assign(uint16_t item, std::string_view value, bool updateLinked, bool validate = true);

        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; }

      private:
        uint16_t get_item_ix(std::string_view name) const;
        std::string_view get_item_name(uint16_t ix) const;

        uint16_t add_item(std::string_view name);

        row *get_row()
        {
            return m_row;
        }

        const row *get_row() const
        {
            return m_row;
        }

        void assign(const item &i, bool updateLinked)
        {
            assign(i.name(), i.value(), updateLinked);
        }

        void swap(uint16_t item, row_handle &r);

        category *m_category = nullptr;
        row *m_row = nullptr;
    };

    // --------------------------------------------------------------------

    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, std::enable_if_t<std::is_same_v<typename ItemIter::value_type, item>, int> = 0>
        row_initializer(ItemIter b, ItemIter e)
            : std::vector<item>(b, e)
        {
        }

        row_initializer(row_handle rh);

        void set_value(std::string_view name, std::string_view value);

        void set_value(const item &i)
        {
            set_value(i.name(), i.value());
        }

        void set_value_if_empty(std::string_view name, std::string_view value);

        void set_value_if_empty(const item &i)
        {
            set_value_if_empty(i.name(), i.value());
        }
    };

    } // namespace cif