string_utils.hpp

/*
 * mstd - Maipa's Standard Library
 *
 * Licensed under the BSD 3-Clause License with Attribution Requirement.
 * See the LICENSE file for details: https://github.com/MAIPA01/mstd/blob/main/LICENSE
 *
 * Copyright (c) 2025, Patryk Antosik (MAIPA01)
 */
 
#pragma once
#ifndef _MSTD_STRING_UTILS_HPP_
    #define _MSTD_STRING_UTILS_HPP_
 
    #include <mstd/config.hpp>
 
    #if !_MSTD_HAS_CXX17
_MSTD_WARNING("this is only available for c++17 and greater!");
    #else
 
        #include <mstd/string_libs.hpp>
 
namespace mstd::utils {
    template<class T, class = void>
    struct string_type_info;
 
    template<class T>
    struct string_type_info<T,
      std::enable_if_t<std::is_same_v<std::remove_cv_t<T>, char> || std::is_same_v<std::remove_cv_t<T>, signed char> ||
                       std::is_same_v<std::remove_cv_t<T>, unsigned char> > > {
        static _MSTD_CONSTEXPR17 size_t size(const T&) { return 1; }
    };
 
    template<class T, size_t N>
    struct string_type_info<T[N],
      std::enable_if_t<std::is_same_v<std::remove_cv_t<T>, char> || std::is_same_v<std::remove_cv_t<T>, signed char> ||
                       std::is_same_v<std::remove_cv_t<T>, unsigned char> > > {
        static _MSTD_CONSTEXPR17 size_t size(const T (&)[N]) { return N - 1; }
    };
 
    template<class T>
    struct string_type_info<T,
      std::enable_if_t<std::is_pointer_v<T> && (std::is_same_v<std::remove_cv_t<std::remove_pointer_t<T> >, char> ||
                                                 std::is_same_v<std::remove_cv_t<std::remove_pointer_t<T> >, signed char> ||
                                                 std::is_same_v<std::remove_cv_t<std::remove_pointer_t<T> >, unsigned char>)> > {
        static _MSTD_CONSTEXPR17 size_t size(T s) { return s ? std::strlen(reinterpret_cast<const char*>(s)) : 0; }
    };
 
    template<class T>
    struct string_type_info<T, std::enable_if_t<std::is_same_v<std::remove_cv_t<T>, std::string> > > {
        static _MSTD_CONSTEXPR17 size_t size(const std::string& s) { return s.size(); }
    };
 
    template<class T>
    struct string_type_info<T, std::enable_if_t<std::is_same_v<std::remove_cv_t<T>, std::string_view> > > {
        static _MSTD_CONSTEXPR17 size_t size(const std::string_view s) { return s.size(); }
    };
 
    template<class String>
    _MSTD_CONSTEXPR17 size_t string_size(String&& s) {
        using string_t = std::remove_reference_t<String>;
        return string_type_info<string_t>::size(s);
    }
} // namespace mstd::utils
 
    #endif
#endif