Task1.3

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

namespace LoginAnalyzer
{
    struct LoginAttempt
    {
        public string IP;
        public DateTime Timestamp;

        public LoginAttempt(string ip, DateTime timestamp)
        {
            IP = ip;
            Timestamp = timestamp;
        }
    }

    class Program
    {
        const int Threshold = 5;

        static readonly TimeSpan TimeWindow = TimeSpan.FromMinutes(10);

        static void Main(string[] args)
        {
            List<LoginAttempt> loginAttempts = new List<LoginAttempt>
            {
                new LoginAttempt("192.168.1.1", DateTime.Now.AddMinutes(-9)),
                new LoginAttempt("192.168.1.1", DateTime.Now.AddMinutes(-8)),
                new LoginAttempt("192.168.1.1", DateTime.Now.AddMinutes(-7)),
                new LoginAttempt("192.168.1.1", DateTime.Now.AddMinutes(-6)),
                new LoginAttempt("192.168.1.1", DateTime.Now.AddMinutes(-5)),
                new LoginAttempt("192.168.1.1", DateTime.Now.AddMinutes(-4)),
                new LoginAttempt("10.0.0.2", DateTime.Now.AddMinutes(-1)),
                new LoginAttempt("10.0.0.2", DateTime.Now.AddMinutes(-1)),
                new LoginAttempt("10.0.0.2", DateTime.Now.AddMinutes(-1)),
            };

            DetectSuspiciousActivity(loginAttempts);
        }

        static void DetectSuspiciousActivity(List<LoginAttempt> attempts)
        {
            var groupedByIP = attempts.GroupBy(a => a.IP);

            foreach (var group in groupedByIP)
            {
                string ip = group.Key;

                DateTime now = DateTime.Now;
                var recentAttempts = group
                    .Where(a => now - a.Timestamp <= TimeWindow)
                    .ToList();

                if (recentAttempts.Count >= Threshold)
                {
                    Console.ForegroundColor = ConsoleColor.Red;
                    Console.WriteLine($"Обнаружено {recentAttempts.Count} попыток входа с IP {ip} за последние 10 минут!");
                    Console.ResetColor();
                }
                else
                {
                    Console.WriteLine($"IP {ip}: {recentAttempts.Count} попыток входа за последние 10 минут.");
                }
            }
        }
    }
}