using System.Security.Cryptography;

using TechnoWorld.Models;

namespace TechnoWorld.Data;

public static class UserStore
{
    private static readonly List<AppUser> Users = [];

    public static bool Register(string login, string name, string password)
    {
        login = login.Trim();
        if (string.IsNullOrWhiteSpace(login) || Find(login) != null)
        {
            return false;
        }

        Users.Add(new AppUser
        {
            Login = login,
            Name = name.Trim(),
            PasswordHash = Hash(password)
        });

        return true;
    }

    public static AppUser? Validate(string login, string password)
    {
        var user = Find(login.Trim());
        if (user == null || user.PasswordHash != Hash(password))
        {
            return null;
        }

        return user;
    }

    private static AppUser? Find(string login)
    {
        return Users.FirstOrDefault(u =>
            u.Login.Equals(login, StringComparison.OrdinalIgnoreCase));
    }

    private static string Hash(string value)
    {
        var bytes = SHA256.HashData(System.Text.Encoding.UTF8.GetBytes(value));
        return Convert.ToHexString(bytes);
    }
}