cppmariadb/include/cppmariadb/result.h

#pragma once

#include <memory>

#include <cppmariadb/config.h>
#include <cppmariadb/impl/handle.h>

namespace cppmariadb
{

    /**
     * @brief Basic result type containing all rows and data from a query.
     */
    struct result :
        public __impl::handle<MYSQL_RES*>
    {
    private:
        bool                    _is_initialized;    //!< Indicates if the result is initialized or not.
        std::unique_ptr<row>    _row;               //!< Current data row of the result.
        mutable column_vector   _columns;           //!< Column information that belongs to this result.
        unsigned long long      _rowindex;          //!< Index of the current row.

    public:
        /**
         * @brief Constructor. Create object from the mariadb handle.
         */
        inline result(MYSQL_RES* h);

        /**
         * @brief Destructor.
         */
        virtual ~result();

        /**
         * @brief Get the number of columns.
         */
        inline unsigned int columncount() const;

        /**
         * @brief Get the columns that belong to this result.
         */
        inline const column_vector& columns() const;

        /**
         * @brief Get the next row of the result or nullptr
         *        if no more rows are stored in the result.
         */
        row* next();

        /**
         * @brief Get the current row.
         */
        inline row* current() const;

        /**
         * @brief Get the current row index.
         */
        inline unsigned long long rowindex() const;

        /**
         * @brief Free the result.
         */
        inline void free();

    protected:
        /**
         * @brief Set the index of the current row.
         */
        inline void rowindex(unsigned long long value);

    private:
        /**
         * @brief Fetch the column information from the database.
         */
        void update_columns() const;
    };

    /**
     * @brief The stored result is a special kind of the result
     *        that stores all result rows on the client.
     */
    struct result_stored
        : public result
    {
        using result::rowindex;

        /**
         * @brief Constructor. Create a new object from the mariadb handle.
         */
        inline result_stored(MYSQL_RES* h);

        /**
         * @brief Set the index of the current row.
         */
        inline void rowindex(unsigned long long index);

        /**
         * @brief Get the number of rows soted in this result.
         */
        inline unsigned long long rowcount() const;
    };

    /**
     * @brief The used result is a special kind of the result
     *        that fetches only the needed rows from the database.
     */
    struct result_used
        : public result
    {
        /**
         * @brief Constructor. Create a new object from the mariadb handle.
         */
        inline result_used(MYSQL_RES* h);

        /**
         * @brief Destructor.
         */
        virtual ~result_used() override;
    };

}