using System;
using System.Collections.Generic;
using System.Linq;

class LoginAttempt
{
    public string Username { get; set; }
    public DateTime Time { get; set; }
    public bool Success { get; set; }
}

class BruteForceDetector
{
    static void Main()
    {
        List<LoginAttempt> logs = new List<LoginAttempt>
        {
            new LoginAttempt { Username = "admin", Time = DateTime.Now.AddSeconds(-50), Success = false },
            new LoginAttempt { Username = "admin", Time = DateTime.Now.AddSeconds(-40), Success = false },
            new LoginAttempt { Username = "admin", Time = DateTime.Now.AddSeconds(-30), Success = false },
            new LoginAttempt { Username = "admin", Time = DateTime.Now.AddSeconds(-20), Success = false },
            new LoginAttempt { Username = "admin", Time = DateTime.Now.AddSeconds(-10), Success = false },
        };

        DetectBruteForce(logs);
    }

    static void DetectBruteForce(List<LoginAttempt> attempts)
    {
        var suspiciousUsers = attempts
            .Where(a => !a.Success && a.Time > DateTime.Now.AddMinutes(-1))
            .GroupBy(a => a.Username)
            .Where(g => g.Count() >= 5);

        foreach (var user in suspiciousUsers)
        {
            Console.WriteLine($"⚠️ ŞÜPHELİ AKTİVİTE: {user.Key} kullanıcısı için brute-force ihtimali!");
        }
    }
}