#pragma once

#include <string_view>

#include <locale>

#include <unordered_map>

#include "crow/utility.h"

namespace crow

{

    /// Hashing function for ci_map (unordered_multimap).

    struct ci_hash

    {

        size_t operator()(const std::string_view key) const

        {

            std::size_t seed = 0;

            std::locale locale;

            for (auto c : key)

                hash_combine(seed, std::toupper(c, locale));

            return seed;

        }

    private:

        static inline void hash_combine(std::size_t& seed, char v)

        {

            std::hash<char> hasher;

            seed ^= hasher(v) + 0x9e3779b9 + (seed << 6) + (seed >> 2);

        }

    };

    /// Equals function for ci_map (unordered_multimap).

    struct ci_key_eq

    {

        bool operator()(const std::string_view l, const std::string_view r) const

        {

            return utility::string_equals(l, r);

        }

    };

    using ci_map = std::unordered_multimap<std::string, std::string, ci_hash, ci_key_eq>;

} // namespace crow