MFCStringLike.hpp

// SPDX-License-Identifier: Apache-2.0
 
#pragma once
 
#include "Core.hpp"
 
#include <concepts>
 
template <typename T>
concept MFCStringLike = requires(T const& t) {
    { t.GetLength() } -> std::same_as<int>;
    { t.GetString() } -> std::same_as<char const*>;
};
 
template <typename T>
    requires(MFCStringLike<T>)
struct SqlDataBinder<T>
{
    static LIGHTWEIGHT_FORCE_INLINE SQLRETURN InputParameter(SQLHSTMT stmt,
                                                             SQLUSMALLINT column,
                                                             T const& value,
                                                             SqlDataBinderCallback& /*cb*/) noexcept
    {
        return SQLBindParameter(stmt,
                                column,
                                SQL_PARAM_INPUT,
                                SQL_C_CHAR,
                                SQL_VARCHAR,
                                value.GetLength(),
                                0,
                                (SQLPOINTER) value.GetString(),
                                0,
                                nullptr);
    }
 
    static LIGHTWEIGHT_FORCE_INLINE std::string_view Inspect(T const& value) noexcept
    {
        return { value.GetString(), static_cast<size_t>(value.GetLength()) };
    }
};
 
// TODO: Use the below instead in order to get full support for MFC-like strings.
 
// template <typename T>
//     requires(MFCStringLike<T>)
// struct SqlBasicStringOperations<T>
// {
//     static char const* Data(MFCStringLike auto const* str) noexcept
//     {
//         return str->GetString();
//     }
//
//     static char* Data(MFCStringLike auto* str) noexcept
//     {
//         return str->GetString();
//     }
//
//     static SQLULEN Size(MFCStringLike auto const* str) noexcept
//     {
//         return static_cast<SQLULEN>(str->GetLength());
//     }
//
//     static void Clear(MFCStringLike auto* str) noexcept
//     {
//         *str = {};
//     }
//
//     static void Reserve(MFCStringLike auto* str, size_t capacity) noexcept
//     {
//         // str->reserve(capacity);
//         // str->resize(str->capacity());
//     }
//
//     static void Resize(MFCStringLike auto* str, SQLLEN indicator) noexcept
//     {
//         // if (indicator > 0)
//         //     str->resize(indicator);
//     }
// };