#pragma once

#include <LittleFS.h>
#include <webui.pb.h> // Ensure this is the version with 'bytes password_hash'
#include <functional> // Required for std::function

// This struct definition is correct and necessary.
struct UserData {
    char username[33];        // 32 chars + null terminator
    uint8_t password_hash[32]; // 32-byte raw SHA-256 hash
};

class Users {
public:
    Users();
    ~Users();

    bool addUser(const char* username, const char* password);
    bool deleteUser(const char* username);
    bool updatePassword(const char* username, const char* newPassword);
    bool userExists(const char* username) const;
    bool checkPassword(const char* username, const char* password) const;
    bool loadUsernamesCallback(const std::function<bool(const char*)>& callback) const;
    size_t getUserCount();
    void reset();

private:
    const char* filename_ = "/users.pb";
    static constexpr size_t MAX_USERS = 5;
    mutable size_t userCount_ = 0;
    mutable bool initialized_ = false;

    void hashPassword(const char* password, uint8_t* hash_out) const;  static bool _iterateUsers(const char* filename, const std::function<bool(UserData&)>& user_callback);
    static bool _transformUsers(const char* src_filename, const std::function<bool(UserData&)>& transform_callback);
};


extern Users users;